(BQ) Part 2 book Diagnostic imaging of the foot and ankle presents the following contents: Midfoot, forefoot, abnormalities of the plantar soft tissues, neurologic diseases, diseases not localized to a specific site, systemic diseases that involve the foot, tumorlike lesions, normal variants.
Chapter Midfoot 4.1 Trauma 131 4.2 Chronic, Posttraumatic, and Degenerative Changes 145 4.1 Trauma Midfoot 4.1 Trauma R Degwert and U Szeimies As described in the Integral Classification of Injuries (ICI), the midfoot consists of a proximal row of bones formed by the navicular and cuboid and a distal row formed by the medial, intermediate, and lateral cuneiforms In the AO/ASIF (Arbeitsgemeinschaft für Osteosynthese / Association for the Study of Internal Fixation) system, the Chopart joint (also called the midtarsal or transverse tarsal joint) defines the boundary line between the midfoot and hindfoot, and injuries to that joint are classified as midfoot injuries The Lisfranc joint marks the distal boundary of the midfoot, and injuries to that joint are assigned to the forefoot 4.1.1 Fractures of the Tarsometatarsal Joint Line (Lisfranc Fractures) Definition A Lisfranc fracture is a fracture that involves the tarsometatarsal joint line, with or without articular dislocation The joint was named after Jacques Lisfranc, who established the tarsometatarsal joint line as a level for foot amputations ! Note Lisfranc fractures are among the most commonly missed severe foot injuries They may alter the biomechanics of the foot, leading to secondary degenerative changes and chronic pain Not infrequently, dislocations have already reduced spontaneously by the time the foot is examined, and the patient presents with a severe capsuloligamentous disruption Superimposed or unperceived signs and symptoms from other injuries are common, as in the case of multiple trauma patients Pain and swelling of the midfoot in a patient with no radiographic abnormalities should always prompt further investigation Symptoms ● ● ● ● ● ● Pain and swelling, predominantly affecting the medial column Inability to stand on the toes Limitation of motion Flattening of the pedal arches Shortening of the foot Possible compartment syndrome Anatomy and Pathology Anatomy ▶ Joints Key anatomic landmarks for the Lisfranc joint line are the tarsometatarsal joints between the cuneiforms, cuboid, and bases of the metatarsals, and the intermetatarsal joints between the trapezoid-shaped bases of the second through fourth metatarsals Anatomically, these joints are amphiarthroses that allow for a small degree of springy motion The base of the second metatarsal, which extends proximally into the cuneiform row, acts as a “keystone” to help stabilize the midfoot ▶ Ligaments The plantar metatarsal ligaments interconnect the second through fourth metatarsals; there is no comparable connection between the first and second metatarsals The tough Lisfranc ligament connects the first ray to the second ray This ligament is approximately 1.5 cm × 0.5 cm thick and consists of two bands—one longitudinal and one oblique, arranged in a Yshaped configuration The Lisfranc ligament extends from the medial cuneiform to the base of the first metatarsal and to the ligament at the base of the second metatarsal ▶ Pedal arches The longitudinal arch of the foot is supported by ligaments (plantar calcaneonavicular ligament, plantar ligament, plantar aponeurosis) and by the flexor muscles The transverse arch derives its ligamentous support from the plantar calcaneonavicular ligament and deep transverse metatarsal ligament It receives most of its muscular support from portions of the posterior tibial tendon and peroneus longus muscle (“stirrup” function) and from the intrinsic muscles and plantar fascia, all of which interact dynamically to maintain the integrity of the plantar vault ▶ Vessels and nerves The perforating branch of the dorsal pedal artery and the deep peroneal nerve run between the first and second metatarsals to the plantar arch and are highly susceptible to injuries Pathology Lisfranc fractures are rare (0.2% of all fractures) They are caused mainly by high-impact trauma—in motor vehicle accidents, for example—but may also result from low-energy trauma due to a stumble or fall (axial compression trauma with the forefoot in a fixed position) Common associated injuries include lesions of the cuneiform bones and fractures of the calcaneocuboid joint, navicular, and metatarsal heads Mechanisms of Injury ● Predisposing Factors No specific predisposing factors are known In principle, any laxity of the capsule and ligaments may increase susceptibility to a Lisfranc injury ● Abduction injury: This mechanism involves forceful abduction of the forefoot while the hindfoot is fixed in place, causing lateral displacement of the metatarsals with a fracture through the base of the second metatarsal (e.g., a fall from horseback with the foot fixed in the stirrup) Plantar flexion injury: This mechanism involves sudden, forceful plantar hyperflexion of the forefoot while the ankle joint is plantar-flexed and the hindfoot is in an equinus position, 131 Midfoot Table 4.1 Quenu and Kuss classification of Lisfranc fracture-dislocations Type Description A Lateral dislocation of multiple rays B Partial dislocation with incomplete homolateral displacement ● ● B1 Isolated medial displacement of the first ray ● B2 Lateral displacement of the second through fifth metatarsals C Divergent dislocation in the Lisfranc joint line with medial displacement of the first metatarsal and lateral displacement of the other metatarsals leading to dorsal dislocation of the proximal metatarsals This may be caused, for example, by landing on tiptoes in ballet, falling backwards with the forefoot fixed, or sudden high-velocity compression in the longitudinal direction (most common form) Dislocation injury: homolateral dorsolateral dislocation of all five metatarsals Classification The Quenu and Kuss system is most widely used for the classification of Lisfranc fracture-dislocations (▶ Table 4.1; ▶ Fig 4.1 and ▶ Fig 4.2) Fig 4.1 Quenu and Kuss classification of Lisfranc fracture-dislocations Fig 4.2 a–c CT images of a Quenu and Kuss type B Lisfranc fracture-dislocation in a 36-year-old woman a Axial MPR with a 0.5-mm slice thickness and 0.3-mm interslice gap shows a fracture through the base of the second and third metatarsals with lateral displacement b Coronal reformatted image shows complete dorsolateral dislocation of the base of the second metatarsal accompanied by partial dorsolateral dislocation of the base of the third metatarsal c Coronal reformatted image shows fractures at the base of the fourth metatarsal and a bony capsular avulsion from the cuboid with lateral displacement The first ray is intact and shows no evidence of a fracture 132 4.1 Trauma Fig 4.3 a–d Lisfranc fracture Four weeks earlier this female patient had suffered an ankle sprain followed by recurring pain in the midfoot, most pronounced between the bases of the first and second metatarsals X-ray films taken elsewhere were reportedly negative a DP radiograph of the foot with the tube angled 20° from the vertical The intertarsal joint line shows possible irregularities but is difficult to evaluate b Supine oblique radiograph of the foot reveals a fracture at the base of the second metatarsal, prompting further investigation by MRI c MRI: Coronal STIR sequence shows fracture edema along the Lisfranc joint line from the first to third metatarsals d Axial PD-weighted fat-sat image shows a basal fracture of the right second metatarsal, edema along the diaphysis of the second metatarsal, and marked contusional bone edema at the base of the first and third metatarsals Imaging (▶ Fig 4.3 and ▶ Fig 4.4) Ultrasound scans may show a plantar hematoma, a dislocation, or a surface discontinuity indicating the presence of a fracture Ultrasound is useful only as an adjunct to other modalities Special views: oblique midfoot, 45° lateromedial and 45° mediolateral If necessary, the study may include static or dynamic stress radiographs Anesthesia may be given to evaluate forefoot abduction relative to the stabilized hindfoot and midfoot or relative to the opposite side Radiographs ! Note Ultrasound ● ● Dorsoplantar (DP) view of the foot with the tube angled 20° from the vertical Supine lateral view of the foot ● ● Abnormalities are often difficult to appreciate on X-ray films due to superimposed structures Approximately 20% of all injuries are missed on AP and oblique radiographs 133 Midfoot Fig 4.4 a–c Fractures of the tarsometatarsal joint line (Lisfranc fracture) caused by direct impact trauma X-ray films taken on site were declared to be negative, but the patient continued to have pain Only sectional imaging can define the full extent of the injury and direct surgical planning a DP radiograph of the foot shows intermetatarsal unsharpness between the first and second metatarsals with a normal distance between the medial cuneiform and base of the second metatarsal b Supine oblique radiograph of the foot shows a questionable fracture at the base of the second metatarsal c MRI: Coronal STIR sequence shows contusional edema along the tarsometatarsal joint line from the first to third metatarsals Important signs: ● Distance between the medial cuneiform and second metatarsal > 2.5 mm: injury to the Lisfranc ligament ● Disruption of the normally straight line along the medial border of the second metatarsal and the intermediate cuneiform on a DP radiograph Interpretation Checklist ● ● ● ● ● CT ● Accurate evaluation requires high-resolution midfoot CT with isotropic voxels (ca 0.5-mm slice thickness) and multiplanar reformatting (MPR) views Three-dimensional (3D) rendering is helpful in patients with complex fracture-dislocations and may include bone segmentation to improve visualization of the fractured joint lines and aid preoperative planning (ideally the radiologist and foot surgeon can work together on interactive displays at the CT workstation) MRI MRI is excellent for visualizing a traumatic injury to the Lisfranc ligament 134 Evaluate the alignment of the Lisfranc joint line Evaluate articular step-offs and degree of disintegration Describe axial malalignment Accurately describe the capsuloligamentous structures, even in the absence of gross incongruity Specifically address the integrity of the Lisfranc ligament Check for associated injuries ! Note Clinical and radiologic findings may suggest the possibility of an impending compartment syndrome Sometimes this can be difficult to recognize Suggestive signs are marked softtissue swelling and possible denervation edema of muscles on MRI Examination Technique ● Standard protocol: prone position, high-resolution multichannel coil 4.1 Trauma Fig 4.4 d–f Fractures of the tarsometatarsal joint line (Lisfranc fracture) caused by direct impact trauma X-ray films taken on site were declared to be negative, but the patient continued to have pain Only sectional imaging can define the full extent of the injury and direct surgical planning d Coronal T1-weighted image shows a bony avulsion with bleeding and tearing of the Lisfranc ligament at the base of the second metatarsal, accompanied by intracapsular hemorrhage of the Lisfranc joint at the level of the third metatarsal e Axial CT shows a multipart fracture of the base of the second metatarsal with bony avulsion of the Lisfranc ligament and a nondisplaced fracture of the third metatarsal base f Sagittal CT shows disintegration of the tarsometatarsal articular surface of the second metatarsal ● Sequences: ○ Coronal double-oblique STIR (short-tau inversion recovery) and T1-weighted ○ Sagittal PD (proton density)-weighted fat-sat (aligned on the metatarsal showing greatest clinical abnormality; use different sagittal planes for the first and fifth metatarsals) ○ Axial T2-weighted ○ Contrast administration is not required ○ Fat-suppressed water-sensitive sequences (STIR is best for fracture detection, while PD-weighted fat-sat gives better anatomical detail) ○ Always image the Lisfranc joint line in three planes ies should be initiated without delay Start with high-resolution MRI of the midfoot, giving attention to possible ligamentous and bony injuries Fracture-dislocations with multiple fragments are more anatomically complex and should be evaluated further by CT with MPRs and 3D rendering Differential Diagnosis ● ● ● ● MRI Findings ● ● Areas of hemorrhage and edema in the soft tissues of the midfoot Marked bone marrow edema caused by fractures and contusions or cancellous bone fractures at the bases of the metatarsals, the cuneiforms, and the cuboid ! Note Joints should be carefully surveyed in all planes to confirm normal articulation Imaging Recommendation ● Cuneiform dislocation Lateral sprain injury (e.g., bifurcate ligament, anterior talofibular ligament, calcaneofibular ligament) Jones fracture of the fifth metatarsal base Navicular fracture Subtalar sprain Treatment Conservative ● ● ● ● Rarely indicated Appropriate for grade I 4.1.2 Lisfranc Ligament Injury (p 136) For dislocations of the Lisfranc joint line with no apparent tendency to redislocate: non–weight bearing in a short leg cast for to weeks, followed by progression to full weightbearing in a walker boot Further rehabilitation may include sensorimotor training (e.g., the Janda program), training therapy, tailored gait and coordination exercises, and orthotic care Modalities of choice: In clinically suspicious cases and especially in cases with abnormal X-ray findings, sectional imaging stud- 135 Midfoot ● ● Mobilization may be supported by injection or infiltration therapy, chiropractic therapy, osteopathy, and orthovolt therapy The patient should not return to sports participation for to months ● ● ● ● ● Operative Surgical treatment is indicated in patients with > mm of displacement and in patients with unstable injuries ● Complete dislocation: emergency reductions can be done in nonfasted patients (closed technique may be used) and then stabilized surgically with a Kirschner wire, screw arthrodesis, or an external fixation device Reductions should be centered on the second metatarsal (the “key fragment”), followed by reduction and stabilization of the first metatarsal and then the third through fifth metatarsals ● Fracture with a subluxated position: Surgical planning is based on CT scans and, if necessary, MRI Reduction begins with the second ray, then proceeds to the first ray and the lateral rays The tarsometatarsal joints can be transfixed with screws or stabilized by dorsal plating Kirschner wires should be used in patients with critical soft tissues The only indication for primary arthrodesis is the complete destruction of the first through third tarsometatarsal joints Transfixation should be in line with the Lisfranc ligament for grade II and III ligament injuries ● Postoperative care: non–weight bearing in a walker boot for to weeks A foot that is stable for exercise can be mobilized without weight bearing Progression to full weight bearing may be started when radiographs confirm fracture healing and transfixation screws have been removed Screws placed across articular surfaces are removed at to weeks ● Pain in the first tarsometatarsal joint Swelling of the midfoot region Inability to bear weight on the affected foot Pain on palpation along the tarsometatarsal joints and in response to a pronation or abduction stress It often takes several days for plantar hematoma to appear Inability to stand on the toes (always compare both sides) Predisposing Factors None Anatomy and Pathology See also 4.1.1 Fractures of the Tarsometatarsal Joint Line (Lisfranc Fractures) (p 131) Anatomy Injury to the Lisfranc ligament is discussed as a separate entity because of its major functional importance The weak point in the six articulations comprising the Lisfranc joint line is the absence of a direct intermetatarsal connection between the bases of the first and second metatarsals The first ray is connected to the second ray only by the cuneometatarsal ligament (Lisfranc ligament, ▶ Fig 4.5) Unlike the four lateral metatarsals, whose bases are interconnected by stable ligament bands, Prognosis, Complications Possible complications: ● Compartment syndrome: requires emergency incision of the four plantar compartments and the dorsal compartment Compartmental pressures should be measured, if possible, but decompression incisions should be made, even if doubt exists ● Injury to the dorsal pedal artery ● Persistent or chronic instability, deformity, displacement, posttraumatic osteoarthritis, chronic pain, and loss of foot mechanics ● Rare: avascular necrosis of the cuneiforms, complex regional pain syndrome (CRPS) 4.1.2 Lisfranc Ligament Injury Definition A Lisfranc ligament injury is an injury of the ligament that connects the medial cuneiform to the second metatarsal Symptoms The clinical picture is highly variable, ranging from nonspecific local pain on pressure and weight bearing to deformity with diastasis between the first and second rays 136 Fig 4.5 Normal MRI appearance of the Lisfranc ligament Coronal PD-weighted fat-sat image shows a hypointense interosseous ligament running obliquely from the medial cuneiform to the base of the second metatarsal (arrows) 4.1 Trauma no transverse ligament exists between the first and second metatarsal bases The strongest ligament within the Lisfranc ligament complex is the interosseous ligament; the plantar and dorsal elements are weaker These anatomic factors account for the high relevance of injuries to the Lisfranc ligament ● Pathology CT Mechanism of Injury CT is used only to exclude a fracture in cases where MRI findings are equivocal and have therapeutic implications A rupture of the Lisfranc ligament leads to significant instability The injury is often missed or misinterpreted on initial examination, resulting in significant, persistent complaints Most injuries occur when the midfoot is twisted while the forefoot is fixed to the ground (e.g., by a cleated shoe) This force causes dorsal displacement of the second metatarsal base with associated diastasis between the bases of the first and second metatarsals Classification Classification by the width of the diastasis (can provide a rough guide): ○ Stage I: < mm diastasis ○ Stage II: > mm diastasis Nunley and Vertullo classification (a more precise classification); ▶ Table 4.2 ● ● MRI Interpretation Checklist ● ● ● ● ● ● ● Ultrasound Ultrasound has only a minor role in the routine work-up of these injuries Increased distance between the medial cuneiform and second metatarsal base, or diastasis increasing to more than 2.5 mm on the weight-bearing radiograph, provide indirect signs of a ruptured Lisfranc ligament Plantar hematoma may be noted in recent injuries Radiographs Radiographs of the foot in three planes Caution: non–weightbearing radiographs often show no abnormalities! Dorsoplantar (DP) and lateral weight-bearing radiographs with side-to-side comparison The following are indirect signs of a Lisfranc ligament rupture: ○ DP: difference in the gap between the base of the first and second cuneiforms is > 2.5 mm ○ Lateral: depressed position of the first metatarsal relative to the fifth metatarsal (measured from the plantar cortex of the first metatarsal at the level of the base to the plantar cortex of the fifth metatarsal) ● ● Continuity of the Lisfranc ligament Location of the tear Bony avulsion Complete fiber disintegration in all portions of the ligament Evaluate alignment Alignment and congruity of the first and second Lisfranc joints and of the remaining tarsometatarsal articulations Exclude associated injuries Examination Technique ● ● Imaging Alternative stress radiographs: abduction and adduction stress can be applied under fluoroscopic control according to the mechanism of injury (may require anesthesia) Stress radiographs can yield more qualitative information than weightbearing views Standard protocol: Prone position, high-resolution multichannel coil; contrast administration is not required Sequences: ○ Double-oblique coronal PD-weighted fat-sat and T1weighted images of the midfoot ○ Sagittal PD-weighted fat-sat (aligned on the first or second metatarsal) ○ Axial PD-weighted fat-sat ○ Axial T2-weighted ○ Coronal STIR sequence may be added to check for any associated bone contusions or fractures MRI Findings (▶ Fig 4.6 and ▶ Fig 4.7) Often the Lisfranc ligament is not completely torn from its attachment, and fat-suppressed images show hyperintense bleeding in and along the ligament with very poor delineation of individual fiber structures These findings suggest a sprain of the Lisfranc ligament, which may also cause significant instability There may be associated bleeding into the joint capsule and soft tissues as well as focal bone contusion edema or malalignment of the first and second metatarsals Imaging Recommendation The modality of choice is MRI In recent years MRI has replaced weight-bearing and stress radiographs in clinically suspicious Table 4.2 Nunley and Vertullo classification of Lisfranc ligament injuries Grade Description I Sprain of the Lisfranc ligament Weight-bearing radiographs show no abnormalities MRI may show signal change in the Lisfranc ligament complex but does not show a discontinuity II 2–5 mm diastasis on weight-bearing radiographs Lateral radiographs show no difference between the affected and unaffected foot MRI may reveal a partial tear of the ligaments III Extensive disruption of the dorsal and plantar elements with pronounced instability of the first ray; diastasis between the first and second metatarsals; decreased medial arch height on weight-bearing radiograph (plantar cortex of the first metatarsal is lower than that of the fifth metatarsal) 137 Midfoot cases with no radiographic abnormalities MRI is well tolerated even by patients in pain and is sensitive enough to visualize the ligament injury It can also detect other injuries that may be missed on radiographs Differential Diagnosis ● ● ● Injury to the calcaneocuboid joint Proximal metatarsal fractures Cuneiform fractures Treatment Conservative ● ● ● ● Nunley and Vertullo grade I injuries with less than mm of diastasis can be treated conservatively in a walker boot or non–weight-bearing short leg cast for to weeks Progress to weight bearing supported by an orthotic insert Sports participation may be resumed at to months With chronic instability, consider secondary surgical treatment by arthrodesis Operative ● ● ● Fig 4.6 Rupture of the Lisfranc ligament in a 19-year-old woman with persistent midfoot pain following a stumble The ligament (arrows) has low signal intensity in the coronal PD-weighted fat-sat image The interosseous fibers are elongated, edematous, and show continuity disruption A faint, focal area of bone contusion is visible at its attachment to the distal medial cuneiform Injury to the capsule and ligaments of the third tarsometatarsal joint is also noted Fresh injury of grade II or higher (> mm diastasis): closed reduction and screw fixation of the ruptured ligament If other instabilities are also present, additional fixation screws can be placed between the first and second metatarsals and through the first tarsometatarsal joint The screws are removed at weeks, followed by progression to full weight bearing aided by orthotics Chronic instability with intact joints: ligament reconstruction with plantaris longus tendon is an option Fixation screws are placed for weeks as in a fresh injury Chronic instability with significant degenerative changes in the first tarsometatarsal joint or with an established secondary fixed deformity: arthrodesis of the first tarsometatarsal joint is combined with correction of the deformity Fig 4.7 a, b Severe Lisfranc joint injury with an extensive rupture of the Lisfranc ligament a Coronal STIR sequence shows bone contusions and fracture edema along the Lisfranc joint line with distal avulsion and bleeding of the Lisfranc ligament (arrow) b Axial PD-weighted fat-sat image shows fractures of the medial cuneiform and second metatarsal base with advanced traumatic disintegration of the Lisfranc ligament (arrow) Fractures of the third and fourth metatarsal bases are also visible 138 4.1 Trauma Prognosis, Complications Pathology Prognosis Mechanism of Injury ! Note A good outcome requires prompt treatment that is tailored to the stage of the injury Most patients can return to their original performance level after appropriate treatment The prognosis is significantly poorer if treatment is delayed Possible Complications ● ● ● ● Lisfranc fractures are often combined with ligamentous injuries Underestimating or missing the injury (sometimes due to spontaneous reduction) Compartment syndrome Chronic joint instability with chronic pain, painful posttraumatic (midfoot) osteoarthritis 4.1.3 Navicular Fracture Definition Fracture of the boat-shaped bone located between the talus and cuneiforms Symptoms ● ● ● ● ● ● Pain Hematoma Malalignment or deformity Decreased forefoot mobility and weight-bearing ability Forefoot malalignment (medial angulation of the forefoot due to dislocation of the talar head) Stress fracture: load-dependent complaints Navicular fractures comprise 37% of all fractures of the foot Associated injuries are common The complex motions of the bone give rise to various potential mechanisms of navicular fractures: forced plantar flexion and inversion, forced eversion, and direct or indirect trauma A stress fracture is the result of excessive pronation of the foot, which may occur in running athletes, for example Several morphologic types of navicular fracture are distinguished: ● Avulsion fractures (bony avulsions of the dorsal capsule): These fractures are caused by forced plantar flexion and inversion that is sufficient to avulse the insertion of the talonavicular ligament ● Tuberosity fractures (insertion of the posterior tibial tendon, anterior deltoid ligament, and spring ligament): Avulsion fractures of the navicular tuberosity result from forced eversion of the foot causing a bony avulsion of the medial stabilizing structures (insertion of the posterior tibial tendon, anterior deltoid ligament, and spring ligament) ● Navicular body fractures: Fractures of the navicular body result from direct or indirect trauma caused by a fall and plantar flexion, or by plantar flexion and abduction of the metatarsal joint ● Stress fractures: A stress fracture results from excessive pronation, which may occur in running athletes, for example Chopart fracture-dislocations account for 15% of all talar injuries and 1% of all dislocations Approximately 80% of patients have a chain of injuries in the affected limb A “nutcracker” fracture of the navicular is caused by forcible adduction, which is usually combined with an axial force (also tearing the bifurcate ligament) ! Note Because high-impact trauma is common, the patterns of injury are often complex It is important, therefore, to evaluate the entire Chopart (midtarsal) joint Dislocations without bony involvement are extremely rare, because considerable force is needed to dislocate the joint due to the strong ligament restraints Dislocations are usually one component of a complex foot injury Predisposing Factors ● ● ● Tarsal coalition Hindfoot arthrodesis Vascular insufficiency predisposing to stress fractures Anatomy and Pathology Anatomy Classifications The navicular bone is the keystone of the medial longitudinal arch or medial column of the foot It is a bony slab with surfaces that articulate with the talar head (spheroidal type of joint motion) and with the medial, intermediate, and lateral cuneiforms The talonavicular joint is the central joint for all complex movements of the foot The navicular is at risk for posttraumatic osteonecrosis due to the relatively poor blood supply to its central third The navicular bone consists of three segments: ● Proximal segment: talar facet ● Middle segment: body, tuberosity, and cuboid facet ● Distal segment: distal facet and adjacent bone ● ● ● AO/ASIF and OTA (Orthopaedic Trauma Association) classifications: ○ 83A: simple ○ 83B: comminuted Classification of Sangeorzan et al: ▶ Table 4.3 Special fracture types: ○ Avulsion fracture: dorsal cortical avulsion at the insertion of the dorsal talonavicular ligament ○ Fracture of the navicular tuberosity: bony avulsion of the posterior tibial tendon insertion ○ Stress fracture: most commonly affects the central (hypovascular) third 139 Tumorlike Lesions ● ● Standard protocol: prone position, high-resolution multichannel coil Sequences: ○ Sagittal and coronal PD-weighted fat-sat ○ Coronal T1-weighted ○ Axial T2-weighted (angled to plane of ankle joint) ○ Axial and sagittal T1-weighted fat-sat after contrast administration MRI findings (▶ Fig 10.11 and ▶ Fig 10.12) Areas of synovial proliferation may be focal, tumorlike (nodular), diffusely distributed in the joint with plaquelike tissue thickening, or may appear as polypous, villuslike proliferative foci Markedly low signal intensity in all pulse sequences is particularly evident on susceptibility-sensitive gradient echo sequences, and complete signal voids are often found With intraosseous involvement, images will almost always show the bone lesion communicating with the bone surface and with the joint Imaging Recommendation Modality of choice: high-resolution multiplanar MRI using gradient echo sequences and IV contrast administration Differential Diagnosis ● ● ● ● ● Proliferative synovitis Chondromatosis with associated synovitis Synovial hemangioma (hyperintense on T2-weighted images, unlike PVNS) Intracapsular osteoid osteoma with reactive synovitis Amyloidosis with intraosseous lesions Treatment Treatment consists of surgical removal This can sometimes be done endoscopically for ankle and subtalar joint lesions There have been attempts to lower the recurrence rate by combining surgery with radiosynoviorthesis Prognosis, Complications Often the tumor cannot be removed completely, which accounts for the relatively high recurrence rate The process may eventually lead to joint destruction 10.7 Bibliography Osteoid Osteoma Allen SD, Saifuddin A Imaging of intra-articular osteoid osteoma Clin Radiol 2003; 58: 845–852 Dahin DC Bone Tumors Springfield: CC Thomas; 1989 Freyschmidt J, Ostertag H, Jundt G Knochentumoren 3rded Berlin: Springer; 2010: 113 Rhee JH, Lewis RB, Murphey MD Primary osseous tumors of the foot and ankle Magn Reson Imaging Clin N Am 2008; 16: 71–91, vi Schajowicz F Tumors and Tumorlike Lesions of Bone and Joints Berlin: Springer; 1994 Van Dyck P, Vanhoenacker FM, Gielen JL, De Schepper AM, Parizel PM Imaging of tumours of the foot and ankle JBR-BTR 2004; 87: 252–257 Woertler K Soft tissue masses in the foot and ankle: characteristics on MR Imaging Semin Musculoskelet Radiol 2005; 9: 227–242 252 Lipoma Diard F, Hauger O, Moinard M, Brunot S, Marcet B Pseudo-cysts, lipomas, infarcts and simple cysts of the calcaneus: are there different or related lesions? JBR-BTR 2007; 90: 315–324 Freyschmidt J, Ostertag H, Jundt G Knochentumoren 3rded Berlin: Springer; 2010: 555 Greenspan A, Raiszadeh K, Riley GM, Matthews D Intraosseous lipoma of the calcaneus Foot Ankle Int 1997; 18: 53–56 Huch K, Werner M, Puhl W, Delling G Calcaneal cyst: a classical simple bone cyst? [Article in German] Z Orthop Ihre Grenzgeb 2004; 142: 625–630 Karthik K, Aarthi S Intraosseous lipoma of the calcaneus mimicking plantar fascitis Foot Ankle Surg 2011; 17: 25–27 doi:10.1016/j.fas.2010.10.004 Aneurysmal Bone Cyst Bush CH, Adler Z, Drane WE, Tamurian R, Scarborough MT, Gibbs CP Percutaneous radionuclide ablation of axial aneurysmal bone cysts AJR Am J Roentgenol 2010; 194: W84-W90 Cebesoy O, Karakok M, Arpacioglu O, Baltaci ET Brown tumor with atypical localization in a normocalcemic patient Arch Orthop Trauma Surg 2007; 127: 577–580 Chowdhry M, Chandrasekar CR, Mohammed R, Grimer RJ Curettage of aneurysmal bone cysts of the feet Foot Ankle Int 2010; 31: 131–135 Cottalorda J, Bourelle S Modern concepts of primary aneurysmal bone cyst Arch Orthop Trauma Surg 2007; 127: 105–114 Dahlin DC, McLeod RA Aneurysmal bone cyst and other nonneoplastic conditions Skeletal Radiol 1982; 8: 243–250 Davies AM, Evans N, Mangham DC, Grimer RJ MR imaging of brown tumour with fluid-fluid levels: a report of three cases Eur Radiol 2001; 11: 1445–1449 Doğan A, Algün E, Kisli E, Harman M, Kösem M, Tosun N Calcaneal brown tumor with primary hyperparathyroidism caused by parathyroid carcinoma: an atypical localization J Foot Ankle Surg 2004; 43: 248–251 Freyschmidt J, Ostertag H, Jundt G Knochentumoren 3rd ed Berlin: Springer; 2010 Ilaslan H, Sundaram M, Unni KK Solid variant of aneurysmal bone cysts in long tubular bones: giant cell reparative granuloma AJR Am J Roentgenol 2003; 180: 1681–1687 Keenan S, Bui-Mansfield LT Musculoskeletal lesions with fluid-fluid level: a pictorial essay J Comput Assist Tomogr 2006; 30: 517–524 Lingg G, Roessner A, Fiedler V et al Das reparative Riesenzellgranulom der Extremitäten Fortschr Röntgenstr 1985; 142: 185–188 Mankin HJ, Hornicek FJ, Ortiz-Cruz E, Villafuerte J, Gebhardt MC Aneurysmal bone cyst: a review of 150 patients J Clin Oncol 2005; 23: 6756–6762 Park YK, Joo M Multicentric telangiectatic osteosarcoma Pathol Int 2001; 51: 200– 203 Schajowicz F Tumors and Tumorlike Lesions of Bone and Joints Berlin: Springer; 1994 Sundaram M, Totty WG, Kyriakos M, et al Imaging findings in pseudocystic osteosarcoma AJR Am J Roentgenol 2001;176:783–788 Van Dyck P, Vanhoenacker FM, Vogel J et al Prevalence, extension and characteristics of fluid-fluid levels in bone and soft tissue tumors Eur Radiol 2006; 16: 2644– 2651 Varshney MK, Rastogi S, Khan SA, Trikha V Is sclerotherapy better than intralesional excision for treating aneurysmal bone cysts? Clin Orthop Relat Res 2010; 468: 1649–1659 Wörtler K, Blasius S, Hillmann A et al MR-Morphologie der primären aneurysmatischen Knochenzyste: Retrospektive Analyse von 38 Fällen Fortschr Röntgenstr 2000; 172: 591–596 Hemangioma Baek HJ, Lee SJ, Cho KH et al Subungual tumors: clinicopathologic correlation with US and MR imaging findings Radiographics 2010; 30: 1621–1636 Bakotic BW, Robinson M, Williams M, Van Woy T, Nutter J, Borkowski P Aggressive epithelioid hemangioendothelioma of the lower extremity: a case report and review of the literature J Foot Ankle Surg 1999; 38: 352–358 Bousson V, Hamzé B, Wybier M et al Soft tissue tumors and pseudotumors of the foot and ankle [Article in French] J Radiol 2008; 89: 21–34 Chang JJ, Lui TH Intramuscular haemangioma of flexor digitorum brevis.Musculus: flexor:digitorum brevis Foot Ankle Surg 2010; 16: e8–e11 10.7 Bibliography Kransdorf MJ Benign soft-tissue tumors in a large referral population: distribution of specific diagnoses by age, sex, and location AJR Am J Roentgenol 1995; 164: 395–402 Llauger J, Palmer J, Monill JM, Franquet T, Bagué S, Rosón N MR imaging of benign soft-tissue masses of the foot and ankle Radiographics 1998; 18: 1481–1498 Mitsionis GI, Pakos EE, Kosta P, Batistatou A, Beris A Intramuscular hemangioma of the foot: A case report and review of the literature Foot Ankle Surg 2010; 16: e27–e29 Requena L, Luis Díaz J, Manzarbeitia F, Carrillo R, Fernández-Herrera J, Kutzner H Cutaneous composite hemangioendothelioma with satellitosis and lymph node metastases J Cutan Pathol 2008; 35: 225–230 Sartoris DJ, Resnick D Magnetic resonance imaging of pediatric foot and ankle disorders J Foot Surg 1990; 29: 489–494 Van Dyck P, Vanhoenacker FM, Gielen JL, De Schepper AM, Parizel PM Imaging of tumours of the foot and ankle JBR-BTR 2004; 87: 252–257 Waldt S, Rechl H, Rummeny EJ, Woertler K Imaging of benign and malignant soft tissue masses of the foot Eur Radiol 2003; 13: 1125–1136 Woertler K Soft tissue masses in the foot and ankle: characteristics on MR Imaging Semin Musculoskelet Radiol 2005; 9: 227–242 Yarmel D, Dormans JP, Pawel BR, Chang B Recurrent pedal hobnail (Dabska-retiform) hemangioendothelioma with forefoot reconstructive surgery using a digital fillet flap J Foot Ankle Surg 2008; 47: 487–493 Ganglion Blitz NM, Amrami KK, Spinner RJ Magnetic resonance imaging of a deep peroneal intraneural ganglion cyst originating from the second metatarsophalangeal joint: a pattern of propagation supporting the unified articular (synovial) theory for the formation of intraneural ganglia J Foot Ankle Surg 2009; 48: 80–84 Delfaut EM, Demondion X, Bieganski A, Thiron MC, Mestdagh H, Cotten A Imaging of foot and ankle nerve entrapment syndromes: from well-demonstrated to unfamiliar sites Radiographics 2003; 23: 613–623 Fujita I, Matsumoto K, Minami T, Kizaki T, Akisue T, Yamamoto T Tarsal tunnel syndrome caused by epineural ganglion of the posterior tibial nerve: report of cases and review of the literature J Foot Ankle Surg 2004; 43: 185–190 Schrank C, Meirer R, Stäbler A, Nerlich A, Reiser M, Putz R Morphology and topography of intraosseous ganglion cysts in the carpus: an anatomic, histopathologic, and magnetic resonance imaging correlation study J Hand Surg Am 2003; 28: 52–61 Woertler K Soft tissue masses in the foot and ankle: characteristics on MR Imaging Semin Musculoskelet Radiol 2005; 9: 227–242 Pigmented Villonodular Synovitis Hughes TH, Sartoris DJ, Schweitzer ME, Resnick DL Pigmented villonodular synovitis: MRI characteristics Skeletal Radiol 1995; 24: 7–12 Kottal RA, Vogler JB, Matamoros A, Alexander AH, Cookson JL Pigmented villonodular synovitis: a report of MR imaging in two cases Radiology 1987; 163: 551–553 Masih S, Antebi A Imaging of pigmented villonodular synovitis Semin Musculoskelet Radiol 2003; 7: 205–216 Ottaviani S, Ayral X, Dougados M, Gossec L Pigmented villonodular synovitis: a retrospective single-center study of 122 cases and review of the literature Semin Arthritis Rheum 2011; 40: 539–546 Saxena A, Perez H Pigmented villonodular synovitis about the ankle: a review of the literature and presentation in 10 athletic patients Foot Ankle Int 2004; 25: 819– 826 Schnirring-Judge M, Lin B Pigmented villonodular synovitis of the ankle-radiation therapy as a primary treatment to reduce recurrence: a case report with 8-year follow-up J Foot Ankle Surg 2011; 50: 108–116 Sharma H, Jane MJ, Reid R Pigmented villonodular synovitis of the foot and ankle: Forty years of experience from the Scottish bone tumor registry J Foot Ankle Surg 2006; 45: 329–336 Sierens P, Shahabpour M, Gombault V, Machiels F, Kichouh M, De Maeseneer M Pigmented villonodular synovitis of the midfoot JBR-BTR 2010; 93: 207–209 253 Chapter 11 11.1 Normal Variants 11.2 Accessory Muscles, Low-Lying Muscle Belly 255 Accessory Ossicles 256 1 11.1 Accessory Muscles, Low-Lying Muscle Belly 11 Normal Variants U Szeimies 11.1 Accessory Muscles, Low-Lying Muscle Belly 11.1.1 Peroneus quartus The peroneus quartus muscle is a normal variant with a reported prevalence of 10% among the normal population However, it can cause clinical symptoms as swelling over the lateral malleolus The muscle and its tendon run medial and posterior to the peroneal tendons, arising from the posterior intermuscular septum and from the peroneus brevis muscle The peroneus quartus has variable insertions, most commonly inserting into a bony prominence (peroneal tubercle) on the lateral side of the calcaneus, on the long or short peroneal tendon, and on the cuboid This normal variant may be a rare cause of lateral ankle complaints It has been suggested that involvement by tendinosis and partial tears of the peroneus brevis tendon may have causal significance 11.1.2 Flexor Digitorum Accessorius Longus 11.1.5 Peroneocalcaneus Internus The peroneocalcaneus internus muscle, also called the “false flexor hallucis longus,” is rare An awareness of this variant is important for preoperative planning, however The flexor hallucis longus is an important landmark for hindfoot arthroscopy as it forms the medial boundary of the neurovascular bundle Consequently, the presence of a “false” flexor hallucis longus could pose a risk of neurovascular injury 11.1.6 Abnormal Musculotendinous Junction Muscle–tendon junctions are subject to considerable variations whose clinical importance is debated in the literature An example is the low-lying peroneus brevis muscle belly, which may predispose to tendon tears A low-lying muscle belly may rarely cause nerve compression syndromes or impingement syndromes, and their imaging may be important in preoperative planning (e.g., soleus insertion point in the Achilles tendon for an Achilles tendon reconstruction) This muscle is reportedly present in up to 15% of the general population It has two bellies, arises from the flexor retinaculum and calcaneus, and fuses to a single tendon that inserts distally into the flexor digitorum longus and flexor hallucis longus tendons The presence of this normal variant may be associated with a nerve compression syndrome (tarsal tunnel syndrome) 11.1.3 Accessory Soleus (▶ Fig 11.1) This is the most common variant The accessory soleus has a separate muscle belly and a separate tendon in the hindfoot It occurs when the soleus splits during embryonic development to form a separate muscular rudiment that arises anterior to the soleus and inserts into the calcaneus anteromedial to the Achilles tendon The accessory soleus may aggravate a clubfoot deformity and prevent its correction This normal variant may be an incidental asymptomatic finding or may become clinically symptomatic during the increased physical activity of adolescence In this case it may become hypertrophic and cause an unexplained hindfoot mass medial to the Achilles tendon with associated tenderness and exercisedependent pain in young runners An awareness of this normal variant is important in making a differential diagnosis 11.1.4 Extensor Hallucis Capsularis This normal variant is located medial to the extensor hallucis longus tendon and arises from either the extensor hallucis longus tendon or the muscle itself It inserts on the first metatarsophalangeal joint capsule It can provide donor material for a possible tendon transfer Fig 11.1 Axial T1-weighted fat-sat image after contrast administration in an athletically active adolescent male with medial Achilles tendon pain MRI shows tissue irritation with increased enhancement in the peritenon of the accessory soleus tendon (arrow) 255 Normal Variants Fig 11.2 Important accessory ossicles in the foot (source: Dihlmann and Stäbler 2010, Fig 16.62) Fig 11.3 Os vesalianum Oblique radiograph of the midfoot The os vesalianum results from failure of the apophysis to fuse with the base of the fifth metatarsal Awareness of this accessory ossicle (arrow) is important in distinguishing it from a fracture Fig 11.4 Os peroneum Oblique sagittal reformatted CT demonstrates the sesamoid bone in the peroneus longus tendon (os peroneum), located lateral and plantar to the cuboid bone ● ● 11.2 Accessory Ossicles The most common accessory ossicles in the foot are listed below and are discussed elsewhere in this book under separate headings based on their anatomic locations (▶ Fig 11.2): ● Accessory navicular: see Accessory Navicular (p 115) in Chapter (Ankle and Hindfoot) Synonyms: os tibiale externum, os naviculare externum, os naviculare secundarium, accessory tarsal navicular ● Cornuate navicular: fusion of the ossification center of the tuberosity with the actual navicular, causing a hornlike protrusion, local tenderness, and a painful callus (see ▶ Fig 11.5) ● Os trigonum: see the section on Os Trigonum Syndrome (p 72) in Chapter (Ankle and Hindfoot) 256 Os peroneum: see ▶ Fig 11.4 Os vesalianum: very rare (prevalence 0.1–1%), proximal to the base of the fifth metatarsal within the peroneus brevis tendon Caused by failure of fusion of the fifth metatarsal apophysis, usually asymptomatic Awareness is important in differentiating a fracture of the fifth metatarsal base from an ossified apophysis of the metatarsal base or Iselin disease (apophysitis of the fifth metatarsal base) Rarely, the os vesalianum may cause a painful callus Symptoms ● ● ● ● Local pain Persistent posttraumatic complaints Impingement symptoms Pain radiating along the tendon 11.2 Accessory Ossicles Fig 11.5 a–c Cornuate navicular The cornuate navicular results from fusion of the ossification center of the os tibiale externum with the navicular bone, resulting in a painful bony protuberance (a “horned” navicular) a Coronal STIR image shows an activated, hornlike protrusion of the navicular with local tenderness b Sagittal PD-weighted fat-sat image shows displacement of the posterior tibial tendon by the bony protuberance c Axial PD-weighted fat-sat image Because of the protuberance and its bony activation, the patient could wear only special footwear Predisposing Factors MRI In cases with fibrous attachment of the ossicle to the parent bone, the attachment may be loosened (“activated”) as a result of trauma Interpretation Checklist ● ● ● Anatomy and Pathology Sesamoid bones and accessory ossification centers may develop into ossicles that have a synchondrotic attachment to the parent bone Accessory ossicles are present in 20% of patients An accessory navicular is the most common type, accounting for one-half of cases Examination Technique ● ● Imaging Radiographs (▶ Fig 11.3) Accessory ossicles are generally well depicted on plain radiographs Ultrasound Accessory ossicles are usually located in the course of tendons as well as ligaments Longitudinal and transverse scans show a short, frequently convex, echogenic bony surface contour with acoustic shadowing A complete survey of the affected connective-tissue structure will yield information on mobility, impingement, etc Shape and consistency of the bone Bony or fibrous attachment Activation (bone marrow edema in the accessory ossicle and adjacent bone, soft tissues, tendon sheath, peritendinitis, tendinosis) Standard protocol: prone position, high-resolution multichannel coil Sequences: ○ Sagittal and coronal PD-weighted fat-sat ○ Coronal T1-weighted ○ Axial T2-weighted (angled to joint plane) ○ Axial oblique (angled to tendon plane) and sagittal T1weighted fat-sat after contrast administration MRI Findings (▶ Fig 11.5) ● ● ● ● Bone marrow edema and contrast enhancement in and around the accessory ossicle Local soft-tissue irritation with synovitis Increased enhancement along the tendon sheath and into the fibro-osseous junction Ossicular fracture or necrosis in rare cases CT (▶ Fig 11.4) Imaging Recommendation CT is sometimes used for detailed imaging (slice thickness 0.5 mm with multiplanar reformatting) to distinguish an accessory ossicle (e.g., sesamoid) from a fracture Modalities of choice: radiography for initial evaluation, MRI to assess activation 257 Normal Variants Differential Diagnosis ● ● ● Osteochondral avulsion Intra-articular loose bodies Posttraumatic calcification It may be difficult to distinguish a bony avulsion from an accessory ossicle in acute trauma cases Sectional imaging (rounded bone edges, fracture edema, soft-tissue edema) will facilitate the diagnosis Differentiation from an old bony avulsion and nonunion is accomplished by noting enhancement characteristics on MRI With the de-novo appearance of a bony structure, the differential diagnosis should include heterotopic ossification and the inflammatory or posttraumatic ossification of a cartilaginous anlage Treatment ● ● ● Insoles to relieve mechanical stresses on the activated region If complaints persist: surgical removal of the ossicle In rare cases: rigid internal fixation to the parent bone Prognosis, Complications If conservative treatment is unsuccessful, surgical fusion or removal of the accessory ossicle can relieve complaints in more than 80% of patients 11.3 Bibliography Accessory Muscles, Low-Lying Muscle Belly Boyd N, Brock H, Meier A, Miller R, Mlady G, Firoozbakhsh K Extensor hallucis capsularis: frequency and identification on MRI Foot Ankle Int 2006; 27: 181–184 Burks JB, DeHeer PA Tarsal tunnel syndrome secondary to an accessory muscle: a case report J Foot Ankle Surg 2001; 40: 401–403 Buschmann WR, Cheung Y, Jahss MH Magnetic resonance imaging of anomalous leg muscles: accessory soleus, peroneus quartus and the flexor digitorum longus accessorius Foot Ankle 1991; 12: 109–116 Chepuri NB, Jacobson JA, Fessell DP, Hayes CW Sonographic appearance of the peroneus quartus muscle: correlation with MR imaging appearance in seven patients Radiology 2001; 218: 415–419 Cheung YY, Rosenberg ZS, Ramsinghani R, Beltran J, Jahss MH Peroneus quartus muscle: MR imaging features Radiology 1997; 202: 745–750 Christodoulou A, Terzidis I, Natsis K, Gigis I, Pournaras J Soleus accessorius, an anomalous muscle in a young athlete: case report and analysis of the literature Br J Sports Med 2004; 38: e38 Hill RV, Gerges L Unusual accessory tendon connecting the hallucal extensors Anat Sci Int 2008; 83: 298–300 Holzmann M, Almudallal N, Rohlck K, Singh R, Lee S, Fredieu J Identification of a flexor digitorum accessorius longus muscle with unique distal attachments Foot (Edinb) 2009; 19: 224–226 258 Karapinar L, Kaya A, Altay T, Ozturk H, Surenkok F Congenital clubfoot associated with an accessory soleus muscle J Am Podiatr Med Assoc 2008; 98: 408–413 Kendi TK, Erakar A, Oktay O, Yildiz HY, Saglik Y Accessory soleus muscle J Am Podiatr Med Assoc 2004; 94: 587–589 Phisitkul P, Amendola A False FHL: a normal variant posing risks in posterior hindfoot endoscopy Arthroscopy 2010; 26: 714–718 Pichler W, Tesch NP, Grechenig W, Leithgoeb O, Windisch G Anatomic variations of the musculotendinous junction of the soleus muscle and its clinical implications Clin Anat 2007; 20: 444–447 Saupe N, Mengiardi B, Pfirrmann CW, Vienne P, Seifert B, Zanetti M Anatomic variants associated with peroneal tendon disorders: MR imaging findings in volunteers with asymptomatic ankles Radiology 2007; 242: 509–517 Trono M, Tueche S, Quintart C, Libotte M, Baillon J Peroneus quartus muscle: a case report and review of the literature Foot Ankle Int 1999; 20: 659–662 Unlu MC, Bilgili M, Akgun I, Kaynak G, Ogut T, Uzun I Abnormal proximal musculotendinous junction of the peroneus brevis muscle as a cause of peroneus brevis tendon tears: a cadaveric study J Foot Ankle Surg 2010; 49: 537–540 Wachter S, Beekman S Peroneus quartus A case report J Am Podiatry Assoc 1983; 73: 523–524 Wittmayer BC, Freed L Diagnosis and surgical management of flexor digitorum accessorius longus-induced tarsal tunnel syndrome J Foot Ankle Surg 2007; 46: 484–487 Zammit J, Singh D The peroneus quartus muscle Anatomy and clinical relevance J Bone Joint Surg Br 2003; 85: 1134–1137 Accessory Ossicles Abramowitz Y, Wollstein R, Barzilay Y et al Outcome of resection of a symptomatic os trigonum J Bone Joint Surg Am 2003; 85-A: 1051–1057 Bashir WA, Lewis S, Cullen N, Connell DA Os peroneum friction syndrome complicated by sesamoid fatigue fracture: a new radiological diagnosis? Case report and literature review Skeletal Radiol 2009; 38: 181–186 Boya H, Ozcan O, Tandoan R, Gỹnal I, Araỗ S Os vesalianum pedis J Am Podiatr Med Assoc 2005; 95: 583–585 Dihlmann W, Stäbler A Gelenke des Fußes einschließlich des oberen Sprunggelenks In: Dihlmann W, Stäbler A, eds Gelenke – Wirbelverbindungen 4th ed Stuttgart: Thieme; 2010: 731 Dorrestijn O, Brouwer RW Bilateral symptomatic os vesalianum pedis: a case report J Foot Ankle Surg 2011; 50: 473–475 Jeppesen JB, Jensen FK, Falborg B, Madsen JL Bone scintigraphy in painful os peroneum syndrome Clin Nucl Med 2011; 36: 209–211 Leonard ZC, Fortin PT Adolescent accessory navicular Foot Ankle Clin 2010; 15: 337–347 Mendez-Castillo A, Burd TA, Kenter K, et al Radiologic case study Os trigonum syndrome Orthopedics 1999;22(12):120–1202, 1208 Mouhsine E, Crevoisier X, Leyvraz PF, Akiki A, Dutoit M, Garofalo R Post-traumatic overload or acute syndrome of the os trigonum: a possible cause of posterior ankle impingement Knee Surg Sports Traumatol Arthrosc 2004; 12: 250–253 Perdikakis E, Grigoraki E, Karantanas A Os naviculare: the multi-ossicle configuration of a normal variant Skeletal Radiol 2011; 40: 85–88 Schratt E, Bosch U, Thermann H Os trigonum-Syndrom Zeichen J Unfallchirurg 1999; 102: 320–323 Scott AT, Sabesan VJ, Saluta JR, Wilson MA, Easley ME Fusion versus excision of the symptomatic Type II accessory navicular: a prospective study Foot Ankle Int 2009; 30: 10–15 Sobel M, Pavlov H, Geppert MJ, Thompson FM, DiCarlo EF, Davis WH Painful os peroneum syndrome: a spectrum of conditions responsible for plantar lateral foot pain Foot Ankle Int 1994; 15: 112–124 Index A abduction injury, Lisfranc fractures 131 accessory lateral ligament 32 accessory muscles 255 accessory navicular 115 – anatomy 115, 116 – differential diagnosis 116 – imaging 115 – pathology 115, 257 – predisposing factors 115 – prognosis 116 – symptoms 115 – treatment 116 accessory ossicles 256, 256 – See also individual ossicles – activated 257 – anatomy 257 – differential diagnosis 258 – imaging 257 – pathology 257 – prognosis 258 – treatment 258 accessory soleus 255, 255 accessory tarsal bones 14 accessory tarsal navicular, see accessory navicular Achilles peritendinitis 92, 94 Achilles tendon insertional tendinopathy 98 – complications 100 – differential diagnosis 99, 99 – imaging 98 – pathology 98 – symptoms 98 – treatment 100 Achilles tendon partial tear 95 – complications 96 – differential diagnosis 95 – Haglund exostosis 100 – imaging 95 – pathology 95 – treatment 96 Achilles tendon pathology 92 Achilles tendon rupture 96 – classification 96 – complications 98 – imaging 96 – pathology 96 – surgery 98, 104 – symptoms 96 – treatment 98 achillodynia 92 – differential diagnosis 94, 94 – forms 92 – imaging 94 – pathology 92 – predisposing factors 92 – treatment 95 adolescents, pes planovalgus 66 Aitken classification, growth plate fractures 58, 59, 61 amputation – osteomyelitis 239 – phalanges 163 aneurysmal bone cyst 244 ankle 21 – anatomy 34 – Charcot arthropathy 229, 233 – chronic bone disorders 79 – chronic cartilage disorders 79 – chronic changes 64 – degenerative changes 64 – diabetic osteoarthropathy 229 – impingement 69 – posttraumatic changes 64 – rheumatoid arthritis 215–217 – trauma 21 ankle fractures 34 – avulsion fracture of the posterior tibial margin and 43–44 – classification 34 – complications 40 – diabetic osteoarthropathy 233 – differential diagnosis 40 – imaging 3, 36, 40–44 – pathology 34 – predisposing factors 34 – prognosis 40 – surgery 40 – symptoms 34 – treatment 40 ankle instability 76 – anatomy/pathology 76 – complications 77 – differential diagnosis 76 – imaging 76 – predisposing factors 76 – prognosis 77 – symptoms 76 – treatment 76 ankle meniscoid lesion 24 ankle osteoarthritis 79 – anatomy 79 – complications 81 – differential diagnosis 81 – imaging 79 – pathology 79 – predisposing factors 79 – prognosis 81 – symptoms 79 – treatment 81 ankle osteoarthritis with varus/valgus deformity 64 – complications 65 – differential diagnosis 65 – imaging 64 – pathology 64 – predisposing factors 64 – prognosis 65 – symptoms 64 – treatment 65 ankylosing spondylitis – pathology 219 – predisposing factors 219 – prognosis 222 – symptoms 219 – treatment 222 anteater snout, calcaneonavicular coalition 90 anterior impingement 70, 70 anterior subtalar dislocation 62 anterior syndesmosis 2, 3, 26, 27 – rupture 43 anterior talofibular ligament 22 – proximal osteochondral avulsion 21 – rupture 22 – tears 21 anterior tibial tendinosis 117 – imaging 117 – treatment 119 anterior tibial tendon 117, 119 – pathology 117 anterior tibial tendon insertional tendinopathy 117 – imaging 117 – pathology 117 – symptoms 117 – treatment 119 anterior tibial tendon rupture 119 – differential diagnosis 119 – imaging 119 – pathology 119 – prognosis/complications 120 – symptoms 119 – treatment 119 anterior tibiofibular ligament 26 anterolateral impingement 69 anteromedial impingement 70 AO/ASIF classification – ankle fractures 34 –– 44A injuries 34–35, 36 –– 44B injuries 35 –– 44C injuries 35, 39 – cuboid fracture 142 – cuneiform fractures 144 – metatarsal fractures 156, 156 – navicular fracture 139 – tibial pilon fracture 41, 45 Arbeitsgemeinschaft für Osteosynthese and Association for the Study of Internal Fixation (AO/ASIF) classification, see AO/ASIF classification Arcq grading system 83 arthrodesis – coalition 92 – midtarsal dislocation 63 articular chondromatosis, see chondromatosis asparagus tip sign 106, 112, 119 autoimmune response, rheumatoid arthritis 213 avascular necrosis (AVN) of the navicular 88 – complications 89 – imaging 88 – treatment 89 avascular necrosis (AVN) of the talus 86 – complications 88 – differential diagnosis 88 – imaging 86 – pathology 86 – posttraumatic 86 – symptoms 86 – treatment 88 avulsion fractures – cuboid 142 – diabetic osteoarthropathy 226, 232 – navicular 139 B Bassett ligament 26 Baxter nerve – compression 196, 198, 199 – plantar fasciitis 178–179 bifurcate ligament 31, 32 bifurcate ligament injuries 31, 31 – complications 32 – differential diagnosis 31, 32 – imaging 31 – pathology 31 – prognosis 32 – treatment 32 bimalleolar ankle fractures 34 bipartite sesamoid 172, 174 blood flow assessment 16 Böhler angle, calcaneal fractures 57 bone disorders, chronic – ankle 79 – hindfoot 79 bone marrow edema syndrome 204 – complications 206 – differential diagnosis 205 – imaging 203, 204 – pathology 204 – predisposing factors 204 – prognosis 206 – symptoms 204 – treatment 205 Boutonniere deformity 220 Bragard classification, osteonecrosis 170 Broden view 8, – subtalar joint instability 78 Brody abscess 236 Brown tumor 247 C calcaneal apophysitis 89 – imaging 89 – predisposing factors 89 calcaneal branch compression 196 calcaneal compartment 191 calcaneal fractures 53 – anatomic reconstruction 57 – classifications 55 – complications 57 – differential diagnosis 56 – extra-articular 55, 57 – fatigue fractures 56 – imaging 56, 57–58 – intra-articular 55 – joint-depression type 55 – mechanism of injury 55 – pathology 55 – prognosis 57 – severity 56 – subtalar joint facet involvement 57 – symptoms 54 – tongue-type 55 – treatment 57 calcaneal lipoma 246 calcaneocuboid joint 32, 63 – instability 33, 149, 150 – osteoarthritis 145 – stability assessment calcaneocuboid joint injuries 32 – classification 33 – complications 34 – differential diagnosis 33 – imaging 33 – injury mechanisms 33 – pathology 33 – prognosis 34 – symptoms 32 – treatment 33 calcaneocuboid ligament 31–32 259 Index – mechanism of injury 33 calcaneofibular ligament 23 – rupture 23 – tears 21 calcaneonavicular coalition 90, 90–91 calcaneonavicular ligament 31 calcaneus 54 – diabetic osteoarthropathy 229, 231, 233 calcaneus radiographs – calcaneus lateral view – DP calcaneus axial projection capillary refill time 16 capsule trauma, ankle/hindfoot 21 cartilage – chronic disorders, ankle/hindfoot 79 – evaluation, ankle osteoarthritis 80 – lesions classification 81 cervical ligament 120 Charcot arthropathy, see diabetic osteoarthropathy Charcot foot, see diabetic osteoarthropathy Charcot osteolysis 230 children – bone marrow edema, see pediatric bone marrow edema – fractures, see pediatric fractures – pes planovalgus 66 chondromas 81–82 chondromatosis 81 – complications 83 – differential diagnosis 82 – imaging 81 – malignant transformation 83 – pathology 81 – predisposing factors 81 – prognosis 83 – symptoms 81 Chopart joint, see midtarsal joint chronic regional pain syndrome (CRPS) 202 – bone marrow edema 203 – complications 204 – differential diagnosis 203 – imaging 203 – pathology 202 – predisposing factors 202 – prognosis 204 – stages 202 – symptoms 202 – treatment 203 – without objective findings 19 claw toe 167 clinical evaluation 13 – clinical examination 13, 19 – diagnostic algorithm 13 – imaging/other tests 13, 19 – referral 13 – special tests 16 coalition 89 – complications 92 – differential diagnosis 91 – fibrous 91 – forms 90 – imaging 90, 90, 91–93 – pathology 90 – pes planovalgus 66 – prognosis 92 – symptoms 89 – treatment 92 Coleman block test 17, 69 collateral ligaments 172 260 color duplex ultrasound scanning, syndesmotic instability 74 compartment syndrome 190 – cuneiform fractures 145 – examination 191 – imaging 191 – interosseous muscles 190 – Lisfranc fractures 136 compartments, foot 191 computed tomography (CT), see CT contrast medium, MRI corn 190 cornuate navicular 115, 256, 257 creatinine clearance CT – 3D imaging – accessory ossicles 256, 257 – aneurysmal bone cyst 245 – ankle fractures 3, 37, 42 –– diabetic osteoarthropathy 233 – ankle osteoarthritis 64, 79 – avascular necrosis of the talus 87 – bifurcate ligament injuries 31 – calcaneal fractures 56, 58 – calcaneocuboid joint injuries 33 – children – chondromatosis 82 – chronic regional pain syndrome 203, 203 – claw toe 168 – coalition 90, 90 – cuboid fracture 143, 143 – cuneiform fractures 144, 144, 145 – diabetic osteoarthropathy 227, 234 – follow-up – fracture of the posterior tibial margin 44 – gouty arthropathy 224 – hammer toe 168 – indications – internal fixation material 3, – intra-articular loose bodies 82 – lipoma 243, 244 – Lisfranc fractures 132, 134, 135 – Lisfranc ligament injury 137 – mallet toe 168 – metatarsal fractures 158, 158 – midtarsal dislocation 63 – navicular fracture 140, 140 – os peroneum 256 – osteochondral lesions of the talus 50 – osteoid osteoma 241, 242, 243 – osteomyelitis 237, 238 – osteonecrosis 170 – pediatric fractures 59, 60, 62 – phalangeal fractures 164 – plantar plate tear 168, 169 – positioning – postoperative imaging – protocol – sesamoid pathology 172 – side-to-side comparison – special techniques – subtalar dislocations 62, 63, 231 – subtalar osteoarthritis 79, 80 – syndesmotic instability 75 – talar fractures 51, 54 – tibial pilon fracture 42, 46 – Tillaux fracture 48 – two-plane fracture 60 cuboid bone 142 – segments 142 cuboid fracture 142 – classification 142 – complications 143 – differential diagnosis 143 – imaging 142 – mechanism of injury 142 – pathology 142 – predisposing factors 142 – surgical treatment 143 – symptoms 142 cuboid tunnel 106, 108 cuneiform fractures 143 – classification 144 – complications 145 – differential diagnosis 145 – imaging 144 – mechanism of injury 144 – pathology 144 – symptoms 143 – treatment 145 cuneiform(s) 144 Cyma line 140 D Dameron and Quill classification, metatarsal fractures 156–157 dancers 103, 156 Danis–Weber classification, ankle fractures 34, 34 decompression 191 deep peroneal nerve 131 – compression 196 deltoid ligament, see medial ligament denervation edema 199 diabetic neuropathic osteoarthropathy (DNOAP), see diabetic osteoarthropathy diabetic osteoarthropathy 226 – classification 231 – demineralization 227 – differential diagnosis 226, 235 – edema phase 226 – fractures 226 – imaging 234 – osteopenic phase 226, 227 – pathology 226 – predisposing factors 226 – primary changes 226 – repair phase 226 – secondary changes 226, 228, 230–234 – site of occurrence 228 – symptoms 226 – therapeutically relevant findings 231 – treatment 228, 233, 235 diagnostic arthroscopy 13 disease-modifying antirheumatic drugs (DMARDs) 218 dislocation injury, Lisfranc fractures 132 distal tarsus, diabetic osteoarthropathy 228, 229–230 doorbell sign 18, 18, 194 dorsal calcaneocuboid ligament 32 dorsal pedal artery 16, 131 double-line sign 87 drawer test 17 E epiphyseal development/maturation disorder of the talus 83 equinus deformity 16 Essex–Lopresti classification, calcaneal fractures 55 extensor brevis 167 extensor hallucis capsularis 255 extensor tendon 167 F false flexor hallucis longus (peroneocalcaneus internus) 103, 255 fat necrosis – lipoma 243 – osteomyelitis 236 fatigue fractures 56, 207 fifth metatarsal 155 – fractures 156, 157 –– treatment 159, 160 – muscle attachments 155 first metatarsal 155 – fractures 156, 158, 159 – growth zone 155 – keratosis 169 – muscle attachments 155 first metatarsophalangeal joint – anatomy 160 – capsuloligamentous injuries 160 –– classification 161, 161 –– complications 163 –– differential diagnosis 162 –– imaging 161 –– pathology 160 –– predisposing factors 160 –– symptoms 160 –– treatment 162 – gout 223–224, 225 – subluxation 162 first tarsometatarsal joint – instability 149, 151 – osteoarthritis, see Lisfranc osteoarthritis – stability testing 18, 18 flatfoot ligament, see spring ligament flexor digitorum accessorius longus 255 flexor hallucis brevis insertional tendinopathy 172, 175 flexor hallucis longus tendon 186 – entrapment syndrome 103 – fluid collections 186 – partial tears 103 – peritendinitis 104 flexor hallucis longus tendon disorders 103 – anatomy 103 – crossover phenomenon 103 – differential diagnosis 104 – imaging 104 – pathology 103 – posterior impingement 103 – prognosis/complications 105 – tendinosis 104 – traumatic rupture 103 – treatment 105 flexor tendon rupture 186 foot muscles 15 forefoot 155 – chronic changes 164 – degenerative changes 164 – posttraumatic changes 164 – rheumatoid arthritis 213, 214–215 – special tests 18 – trauma 155 forefoot compartment 191 Index fourth metatarsal – fractures 156, 159 – growth zone 155 fracture of the posterior tibial margin 26, 34, 43 – anatomy 43 – ankle fractures and 43–44 – differential diagnosis 44 – imaging 43 – pathology 43 – prognosis/complications 44 – treatment 44 fracture(s) 34 – See also individual types – radiography – rheumatoid arthritis 213, 215, 215 – special tests 16 – trauma 21 hindfoot alignment view, see Saltzman view hindfoot varus 105 history-taking 13, 19 – relevant questions 13 Hoffmann–Tinel sign, medial malleolus 18 human papillomavirus 190 G imaging techniques – See also individual techniques immobilization, pediatric fractures 60 incipient osteoarthritis 71 infection – diabetic osteoarthropathy 228, 235 – osteomyelitis 236 inferior peroneal retinaculum 105 inflammatory joint diseases 213 insertional tendinopathy – Achilles tendon, see Achilles tendon insertional tendinopathy – anterior tibial tendon, see anterior tibial tendon insertional tendinopathy – flexor hallucis brevis 172, 175 – peroneal tendon pathology 106 – peroneus brevis tendon 106 – peroneus longus tendon 106, 109 – plantar fascia, see plantar fasciitis – posterior tibial tendon 114 inspection 14 insufficiency fractures 207 intermalleolar ligament 26 intermediate cuneiform 144 intermetatarsal joints 131 internal fixation, pediatric fractures 60 interossei muscles 167 interosseous talocalcaneal ligament 120 interphalangeal joints – anatomy 163 – hyperextension deformity 187 – osteoarthritis 220 – surgical correction 170 intra-articular loose bodies 81, 82 intratendinous subluxation 109 intrinsic muscles 167 ischemia of the navicular, see avascular necrosis (AVN) of the navicular ischemic osteonecrosis 83–84 Gaensslen maneuver 18, 213 ganglia (ganglion), see ganglion cysts ganglion cysts 247, 248 – complications 249 – differential diagnosis 249 – imaging 249 – pathology 249 – sites of predilection 249 – treatment 249 giant cell tumor 246 Gissane angle, calcaneal fractures 57 gout 222 gouty arthropathy 222 – differential diagnosis 224 – imaging 223 – pathology 223 – predisposing factors 223 – prognosis 226 – symptoms 223 – treatment 226 gouty tophi 223–224, 225 H Haglund exostosis 100, 101 hallucis longus and digitorum longus intersection syndrome 186 hallux rigidus 165, 167 hallux valgus 164, 187 – imaging 165 – pathology 165 – prognosis/complications 165 – treatment 165 halo phenomenon 112, 117 hammer toe 167, 168 Hawkins sign 86 heel compression test 16 hemangioma 247 hematoma – anterior tibial tendon rupture 119 – lateral ligaments injury/trauma 22 high-volume injection therapy, paratenon adhesions 95 hindfoot 21 – axial malalignment 64 – chronic cartilage disorders 79 – chronic changes 64 – chronic pain, differential diagnosis 121, 122 – degenerative changes 64 – fractures 34 – impingement 69 – instability 74 – inversion, tiptoe stance 16 – posttraumatic changes 64 I J Jogger’s foot (medial plantar nerve compression) 196, 199 joint stability tests 17 Jones fracture 156, 157, 208 K Kager triangle, achillodynia 94 Kleiger fracture, see Tillaux fracture knot of Henry 186 Köhler disease type I, see avascular necrosis (AVN) of the navicular Köhler disease type II 170 – imaging 170, 171 Köhler–Freiberg disease, see Köhler disease type II L Larsen–Dale–Eek scale, rheumatoid arthritis 213 lateral compartment 191 lateral cuneiform 144 lateral ligament trauma/injury 21 – bony avulsions 21 – children 21, 23 – complications 24 – differential diagnosis 24 – imaging 21 – medial ligament lesion and 21 – pathology 21 – predisposing factors 21 – prognosis 24 – repetitive trauma 23 – strain grades 21 – symptoms 21 – tears 34, 36 – treatment 24 lateral ligaments 21 lateral plantar nerve – compression 196 – first branch, see Baxter nerve lateral subtalar dislocation 62 lateral/medial ankle stability test 17 Lauge–Hansen classification, ankle fractures 34, 35 Le Fort–Wagstaffe fractures 35 Ledderhose disease 181, 182 – imaging 182, 183 ligament trauma, ankle/hindfoot 21 lipoma 243 – differential diagnosis 244 – imaging 243 –– recommendation 244 – malignant transformation 244 – pathology 243 – prognosis 244 – symptoms 243 – treatment 244 Lisfranc fractures 131 – associated injuries 131 – capsuloligamentous disruption 131 – classification 132, 132, 132 – complications 136 – differential diagnosis 135 – emergency reductions 136 – imaging 133, 133, 134 – mechanisms of injury 131 – pathology 131 – postoperative care 136 – subluxated position 136 – symptoms 131 – treatment 135 Lisfranc joint line 131 – rheumatoid arthritis 215 Lisfranc ligament 131, 136, 136, 147 Lisfranc ligament injury 136 – classification 137, 137 – complications 139 – differential diagnosis 138 – hyperintense bleeding 137 – imaging 137 – mechanism of injury 137 – pathology 137 – prognosis 139 – rupture 137, 138 – sprain 137 – surgery 138 – symptoms 136 – treatment 138 Lisfranc osteoarthritis 147 – differential diagnosis 148 – imaging 148 – predisposing factors 147 – prognosis/complications 149 – symptoms 147 – treatment 148 longitudinal arch 131 longitudinal plantar ligament 155 lumbricals 167 lymphangioma 247 M magic angle phenomenon magnetic resonance imaging (MRI), see MRI Maisonneuve fractures 36, 39, 44 – direct impact trauma vs 44 – imaging 44, 46 mallet toe 167 march fractures 155, 207 medial column 150 – instability 149, 151 medial compartment 191 medial cuneiform 144 medial ligament 24 medial ligament trauma/injury 24 – complications 26 – differential diagnosis 26 – imaging 24 – lateral ligament sprains and 21 – pathology 24 – predisposing factors 24 – prognosis 26 – symptoms 24 – treatment 26 medial metatarsosesamoid ligament 160 medial plantar nerve compression (Jogger’s foot) 199 medial subtalar dislocation 61–62 metatarsal fractures 155 – See also individual bones – classification 156, 156, 156, 157 – complications 159 – diabetic osteoarthropathy 228, 228 – differential diagnosis 158 – frequency distribution 155 – imaging 156 – mechanism of injury 155 – pathology 155 – predisposing factors 155 – proximal 156 – surgery indications 159 – symptoms 155 – treatment 159, 160 –– children 159 metatarsal osteonecrosis 170 – differential diagnosis 172 – imaging 170 – navicular fracture 141 – pathology 170 – predisposing factors 170 – prognosis 172 – symptoms 170 – treatment 172 metatarsal(s) 155 – See also individual bones – diaphysis 155 261 Index – head 155 metatarsalgia 187 – differential diagnosis 168, 188 – imaging 187 – pathology 187 – prognosis 189 – surgical complications 189 – symptoms 187 – treatment 189 metatarsophalangeal joints 163, 168 – dislocation 168, 187 – first, see first metatarsophalangeal joint – plantar plate 160 – rheumatoid arthritis 214 – subluxation 169, 187 – surgical correction 170 microfractures, see stress fractures midfoot 131 – anatomy 131 – boundaries 131 – chronic changes 145 – collapse, diabetic osteoarthropathy 228, 228, 235 – degenerative changes 145 – instability 149 – osteoarthritis 145 – posttraumatic changes 145 – trauma 131 midtarsal joint 32, 63 – dislocation 63 Mikulicz line 64 Morton neuroma 194 – complications 195 – differential diagnosis 194 – imaging 2, 194 – pathology 194 – predisposing factors 194 – symptoms 194 – tests 18 – treatment 194 motion tests 14 moving-hand technique, palpation 14 MRI – accessory navicular 115, 116–117 – accessory ossicles 257, 257, 257 – accessory soleus 255 – Achilles tendon insertional tendinopathy 98, 99 – Achilles tendon partial tear 95, 96 – Achilles tendon rupture 97, 97 – achillodynia 94, 94 – aneurysmal bone cyst 245, 246 –– examination technique 245 – ankle fractures 37, 41 – ankle instability 76, 77 – ankle osteoarthritis 79, 80 – ankle osteoarthritis with varus/valgus deformity 64 – anterior impingement 71 – anterior syndesmosis 2, – anterior tibial tendinosis 117, 118 – anterior tibial tendon insertional tendinopathy 117, 118 – anterior tibial tendon rupture 119, 120 – anterolateral impingement 69, 70 – anteromedial impingement 71, 71 – asymptomatic interval – avascular necrosis of the navicular 88 – avascular necrosis of the talus 87, 87 – bifurcate ligament injuries 31, 32 262 – bone marrow edema syndrome 203, 204, 205–206 – calcaneal apophysitis 89, 90 – calcaneal fractures 56, 57 – calcaneocuboid joint injuries 33 – calcaneocuboid joint instability 149, 150 – calcaneocuboid osteoarthritis 146 – chondromatosis 82, 82 – chronic regional pain syndrome 203, 204 – claw toe 168 – coalition 91, 91, 92–93 – coil – compartment syndrome 191 – contrast medium – cornuate navicular 257 – cuboid fracture 143 – cuneiform fractures 144, 145 – diabetic osteoarthropathy 227, 234, 234 – differential diagnosis 102 – first metatarsophalangeal joint, capsuloligamentous injuries 161, 162 – flexor hallucis longus tendon disorders 104, 104 – fracture of the posterior tibial margin 44, 47–48 – ganglion cysts 249, 250 – gouty arthropathy 224, 225 – Haglund exostosis 100, 101 – hallucis longus and digitorum longus intersection syndrome 186 – hallux valgus 165, 166 – hammer toe 168, 168, 169 – hemangioma 247, 248 – hindfoot tendon pathology 2, – imaging strategy – lateral ligaments injury/trauma 21, 22–23 – Ledderhose disease 182, 183 – lipoma 243, 245–246 – Lisfranc fractures 133–134, 134, 135 – Lisfranc ligament injury 137, 138 – Lisfranc osteoarthritis 148, 148 – Maisonneuve fractures 46 – mallet toe 168 – medial column instability 150, 151 – medial ligament injuries 25, 25 – metatarsal fractures 158 – metatarsalgia 188, 189 – midfoot tendon pathology 2, – midtarsal dislocation 63 – Morton neuroma 2, 194 – navicular fracture 140 – navicular stress fractures 140 – naviculocuneiform joint osteoarthritis 146, 147 – nerve compression syndromes 197– 198, 198, 199 – os trigonum syndrome 73, 74 – osteochondral lesions of the talus 50, 50, 51, 84, 84, 84, 85 – osteoid osteoma 241, 242 – osteomyelitis 236–238, 238 – osteonecrosis 170, 171 – overuse edema 206, 207 – pediatric bone marrow edema 210, 210 – pediatric fractures 59, 59, 61 – peroneal split syndrome 111, 111 – peroneal tendon pathology 106, 107–109 – peroneal tendon subluxation/dislocation 109, 110 – pes planovalgus 66 – phalangeal fractures 164 – pigmented villonodular synovitis 250, 251 – plantar fasciitis 178, 179–180 – plantar fat pad atrophy 183 – plantar heel spur 180 – plantar plate 169 – plantar plate tear 168, 169 – plantar vein thrombosis 185, 185 – plantar warts 190, 190 – positioning – post-exercise 3, 19 – posterior impingement 72, 73 – posterior tibial tendon dysfunction 112, 113–114 – posteromedial impingement 71 – prognosis 102 – psoriatic arthropathy 223 – rheumatoid arthritis 213, 217–218 – sequences –– for specific investigations 2, – seronegative spondylarthropathies 221, 224–225 – sesamoid pathology 173, 173, 174– 175 – sinus tarsi syndrome 120, 121 – spring ligament injury 29, 30 – stress fractures 208, 209 – subtalar dislocations 62 – subtalar joint instability 78, 78 – subtalar osteoarthritis 79 – syndesmosis rupture 27, 28–29 – syndesmotic instability 75, 75 – system – talar fractures 52, 52 – talonavicular osteoarthritis 146, 146 – tennis leg 102, 102, 103 – Tillaux fracture 49 – traction spur 99 – traumatic epiphyseal separation of the fibula 59 – treatment 102 Mulder click test 18 multidetector-row spiral computed tomography (CT), see CT muscle belly, low-lying 255 muscle function tests 15 – strength rating 15 muscular atrophy 16 muscular sling shortening, calcaneal apophysitis 89 musculo-tendinous junction, abnormal 255 Myerson classification, Achilles tendon rupture 96 N navicular body fractures 139 navicular bone 139 – blood supply 88 – segments 139 navicular fracture 139 – classification 139, 140 – complications 141 – differential diagnosis 141 – imaging 140 – mechanism of injury 139 – morphologic types 139 – pathology 139 – predisposing factors 139 – surgery 141 – symptoms 139 – treatment 141 – types 139 navicular tuberosity fractures 139 naviculocuneiform joint – anatomy 146 – instability 149 – osteoarthritis 145, 147 nerve compression syndromes 195, 196 – See also individual syndromes – differential diagnosis 200 – imaging 198 – pathology 198 – predisposing factors 197 – prognosis 200 – symptoms 197 – treatment 200 nerve irritation tests 18 neurologic diseases 194 neuropathic osteoarthropathy (NOAP), see diabetic osteoarthropathy neuropathy, osteomyelitis vs 238 neutral-0 method 14 non-specific site diseases 202 non–weight-bearing radiographs 4, – ankle joint –– indications –– positioning 7, – ankle lateral view – AP projection – DP projection – indications – lateral view – mortise view – oblique views 4, – positioning normal variants 255 Nunley and Vertullo classification, Lisfranc ligament injury 137 nutcracker fractures 139, 142–143 O os naviculare externum, see accessory navicular os naviculare secundarium, see accessory navicular os peroneum 106, 107, 256 os tibiale externum, see accessory navicular os trigonum 73, 75 os trigonum syndrome 72, 103 – differential diagnosis 74 – imaging 73 – pathology 73 – prognosis/complications 74 – symptoms 73 – treatment 74 os vesalianum 256, 256 osteitis, see osteomyelitis osteoarthritis – ankle, see ankle osteoarthritis – ankle joint with varus/valgus deformity, see ankle osteoarthritis with varus/valgus deformity – calcaneocuboid joint 145 – definition 79 – incipient 71 – interphalangeal joints 220 Index – Lisfranc joint line, see Lisfranc osteoarthritis – midfoot 145 – naviculocuneiform joint 145, 147 – pathology 79 – posttraumatic, navicular 141 – sesamoid 172, 174 – subchondral bone 80 – subtalar, see subtalar osteoarthritis – talonavicular 146 – talonavicular joint 145 – tarsometatarsal joints, see Lisfranc osteoarthritis – with capsular chondromas and osteomas 82 osteoarthropathy, see diabetic osteoarthropathy osteochondosis, sesamoid cartilage 172 osteochondral fragment formation 50 osteochondral grafting 50 osteochondral lesions of the talus 49, 83 – classifications 49, 83 – complications 51, 85 – differential diagnosis 50, 85, 86 – grading systems 83 – imaging 50, 83 – osteochondritis dissecans vs 86 – pathology 49, 83 – posttraumatic 83 – predisposing factors 83 – prognosis 51, 85, 86 – staging 49 – symptoms 49, 83 – treatment 50, 85 osteochondritis dissecans, see osteochondral lesions of the talus osteoid osteoma 241 – anatomy 241 – bone edema 241 – complications 243 – differential diagnosis 243 – imaging 241, 242 – intra-articular lesions 241 – nidus 241 – pathology 241 – predisposing factors 241 – prognosis 243 – sites of occurrence 241 – treatment 243 osteomyelitis 236 – acute 236, 236, 237, 237–238 – bone sequestra 237, 238 – chronic 236 – diabetic osteoarthropathy 226 – differential diagnosis 238 – fat necrosis 236, 238 – hematogenous vs exogenous 236 – imaging 236, 236, 237–238 – neuropathy vs 238 – pathology 236 – predisposing factors 236 – prognosis 239 – radiography 236 – subacute 236 – surgical treatment 239 – symptoms 236 osteonecrosis – ischemic 83–84 – metatarsals, see metatarsal osteonecrosis – sesamoid 172–174, 174 osteophytes – anterior impingement 70–71 – hallux rigidus 166 – rheumatoid arthritis 213 Ottawa ankle rules 37 Outerbridge classification, cartilage lesions 81 overuse edema 206 P Paget disease 247 pain history 14 palpation 14, 15 paratenon adhesions 95 pedal arches 131 pediatric bone marrow edema 209 – anatomy 210 – differential diagnosis 210 – imaging 210 – predisposing factors 209 – prognosis 211 – symptoms 209 – treatment 211 pediatric fractures 57 – complications 60 – differential diagnosis 59 – distal tibia 57 – imaging 59, 59, 60–62 – pathology 58 – predisposing factors 58 – prognosis 60 – toes 163 – treatment 60, 159 peritalar dislocation, see subtalar dislocations peroneal muscle paralysis 105 peroneal retinaculum pathology 106, 108 peroneal split syndrome 110 – distal fibular tip 106 – imaging 111 peroneal tendon pathology 105 – complications 107 – differential diagnosis 107 – imaging 106 – insertional tendinopathy 106 – partial tear 106 – pathology 106 – peritendinitis 106, 107 – predisposing factors 105 – ruptures 106–107, 109 – subluxation/dislocation 107 – symptoms 105 – tendinosis 106 – treatment 107 peroneal tendon(s) 105, 105 – function 105 – tendon sheath 105 peroneal tubercle 106, 108 peroneocalcaneus internus (false flexor hallucis longus) 103, 255 peroneus brevis tendon 105, 105, 105, 111 – disorders, see peroneal tendon pathology – insertional tendinopathy 106 – rupture 106–107 peroneus longus tendon 105, 105, 106, 111 – disorders, see peroneal tendon pathology – insertional tendinopathy 106, 109 – rupture 107 peroneus quartus muscle 255 pes calcaneocavus 68 pes cavovarus 68 pes cavus 66 – imaging 68 – pathology 68 – predisposing factors 68 – symptoms 66 – treatment 69 pes equinovarus 105 pes planovalgus 65 – complications 66 – differential diagnosis 66 – imaging 66 – pathology 66 – predisposing factors 65 – prognosis 66 – symptoms 65 – treatment 66 pes planus 228 phalangeal fractures 163 – classification 163, 163 – differential diagnosis 164 – imaging 163 – mechanism of injury 163 – pathology 163 – predisposing factors 163 – prognosis 164 – symptoms 163 – treatment 164 phalanx 163 pigmented villonodular synovitis (PVNS) 249 – anatomy/pathology 250 – differential diagnosis 252 – imaging 250 – predisposing factors 250 – prognosis/complications 252 – symptoms 250 – treatment 252 pilon fractures 233 plantar calcaneonavicular ligament tear, see spring ligament injury plantar fascia 178 – rupture 178, 181 plantar fasciitis 178 – differential diagnosis 179 – imaging 178 – predisposing factors 178 – prognosis 179 – surgical complications 179 – symptoms 178 – treatment 179 plantar fat pad 183 – degenerative changes 183 plantar fat pad atrophy 183, 184 plantar fibromatosis, see Ledderhose disease plantar flexion injury, Lisfranc fractures 131 plantar heel spur 178, 179 plantar interdigital nerve neuroma, see Morton neuroma plantar intermetatarsal nerve branch compression 194 plantar keratosis 169, 188, 189 plantar metatarsal ligaments 131 plantar plate 160, 168 – chronic insufficiency 169 plantar plate tear 160, 162 – chronic 167 – imaging 168, 169 – pathology 168 – predisposing factors 167 – prognosis 170 – symptoms 167 – traumatic 161 – treatment 170 plantar soft tissue abnormalities 178 plantar vein thrombosis 184 – imaging 185 – pathology 185 – predisposing factors 184 plantar venous plexus 185 plantar warts 190, 190 post-exercise MRI 3, 19 posterior impingement 72 posterior subtalar dislocation 62 posterior syndesmosis 26 – trauma 26 posterior talofibular ligament 26 posterior tibial margin fracture, see fracture of the posterior tibial margin posterior tibial tendon 112 – insertional tendinopathy 114 – ossicle within 116 posterior tibial tendon dysfunction 112 – acute tendinopathy 112 – differential diagnosis 115 – imaging 112 – partial tear 112 – pathology 112 – predisposing factors 112 – prognosis/complications 115 – stages 112 – symptoms 112 – treatment 115 posterior tibial tendon insufficiency 112, 113 posterior tibial tendon peritendinitis 113 posterior tibial tendon rupture 112, 114 – treatment 66 posterior tibial tendon tendinosis 112, 113 – chronic 112 posterior tibiofibular ligament 26 posteromedial impingement 70 pronation/abduction test 17 provocative testing 19 psoriasis – bone edema 222 – complications 222 – imaging 221–223 – joint involvement 219 – pathology 220 – predisposing factors 219 – prognosis 222 – skin changes 219 – symptoms 219 – treatment 222 push-up test 18, 18 Q Quenu and Kuss classification, Lisfranc fractures 132, 132 R radiography – accessory navicular 115 – accessory ossicles 256, 257, 257 263 Index – Achilles tendon insertional tendinopathy 98 – achillodynia 94 – aneurysmal bone cyst 245 – ankle fractures 36, 40–41, 43, 233 – ankle instability 76 – ankle joint –– AP weight-bearing view 6, –– indications –– lateral view –– oblique views –– positioning –– weight-bearing mortise view – ankle osteoarthritis 79 – ankle osteoarthritis with varus/valgus deformity 64, 65 – anterior impingement 70 – anterior tibial tendon rupture 119 – anterolateral impingement 69 – anteromedial impingement 70 – avascular necrosis of the navicular 88 – avascular necrosis of the talus 86 – axial relationship determination – bifurcate ligament injuries 31 – bone marrow edema syndrome 204 – Boutonniere deformity 220 – calcaneal apophysitis 89 – calcaneal fractures 56 – calcaneocuboid joint injuries 33 – calcaneocuboid joint instability 149, 150 – calcaneocuboid osteoarthritis 146 – chondromatosis 81 – chronic regional pain syndrome 203 – claw toe 168 – coalition 90, 93 – compartment syndrome 191 – cuboid fracture 143 – cuneiform fractures 144 – diabetic osteoarthropathy 227–228, 234 – first metatarsophalangeal joint, capsuloligamentous injuries 161 – flexor hallucis longus tendon disorders 104 – forefoot – fracture of the posterior tibial margin 43 – ganglion cysts 249 – glassy bones 203 – gouty arthropathy 223, 225 – Haglund exostosis 100 – hallucis longus and digitorum longus intersection syndrome 186 – hallux rigidus 166, 167 – hallux valgus 165 – hammer toe 168 – hemangioma 247 – hindfoot – interphalangeal joint osteoarthritis 220 – intra-articular loose bodies 81 – lateral ligaments injury/trauma 21 – Ledderhose disease 182 – lipoma 243 – Lisfranc fractures 133, 133, 134 – Lisfranc ligament injury 137 – Lisfranc osteoarthritis 148 – Maisonneuve fractures 44, 46 – mallet toe 168 – medial column instability 150 – medial ligament injuries 24 264 – – – – – – metatarsal fractures 157, 157 metatarsalgia 187, 188 midtarsal dislocation 63 navicular fracture 140 navicular stress fractures 140 naviculocuneiform osteoarthritis 146 – nerve compression syndromes 198 – nidus 241 – os trigonum syndrome 73, 73 – os vesalianum 256 – osteochondral lesions of the talus 50, 83 – osteoid osteoma 241 – osteonecrosis 170, 170 – overuse edema 206 – pediatric fractures 59, 61 – peroneal split syndrome 111 – peroneal tendon pathology 106 – peroneal tendon subluxation/dislocation 109 – pes cavovarus 64 – pes cavus 68, 68 – pes planovalgus 66, 67 – phalangeal fractures 163, 164 – pigmented villonodular synovitis 250 – plantar fasciitis 178 – plantar fat pad atrophy 183 – plantar heel spur 180, 181 – plantar plate tear 168 – plantar vein thrombosis 185 – posterior impingement 72 – posterior tibial tendon dysfunction 112 – posteromedial impingement 70 – psoriatic arthropathy 221, 221–223 – rheumatoid arthritis 213, 214–216 – seronegative spondylarthropathies 220 – sesamoid pathology 172, 173 – sesamoids – sinus tarsi syndrome 120 – spring ligament injury 29 – stress fractures 208 – subtalar dislocations 61, 231 – subtalar joint instability 78 – subtalar osteoarthritis 79 – syndesmosis rupture 27 – syndesmotic instability 74 – talar fractures 51, 53–54, 232 – talonavicular osteoarthritis 146 – tibial pilon fracture 42, 46 – Tillaux fracture 48, 49 – toes – traction spur 98 – weight-bearing, see weight-bearing radiographs red bone marrow 209 reduction, subtalar dislocations 62 referral 13 reflex sympathetic dystrophy, see chronic regional pain syndrome (CRPS) Reichel disease, see chondromatosis reparative giant cell granuloma (solid aneurysmal bone cyst) 246 rheumatoid arthritis 213 – chronic synovitis (pannus tissue) 213, 215, 217–218 – clinical appearance 214 – complications 219 – differential diagnosis 218 – imaging 213 – partial remission 219 – pathology 213 – predisposing factors 213 – preventive treatment 218 – prognosis 219 – reconstructive treatment 218 – surgical treatment 217, 218 – symptoms 213 – treatment 218 rheumatoid factors 213 rocker-bottom foot deformity 228, 230 Rowe classification, calcaneal fractures 56 Rubinstein–Tabyi syndrome 145 running, vertical load 155 ruptured Achilles tendon 16 S Salter–Harris classification, growth plate fractures 58, 59, 61 Saltzman view 9, 10 – ankle osteoarthritis with varus/valgus deformity 64, 65 – pes cavus 69 – pes planovalgus 66, 67 – rheumatoid arthritis 213 – subtalar dislocations 231 sand toe 160–161 Sanders classification, calcaneal fractures 55, 55 saphenous nerve compression 196 sausage toe 219, 222 scintigraphy – metatarsal fractures 158 – osteoid osteoma 241 – osteomyelitis 238 second metatarsal – anatomy 155 – fractures 156, 159 – growth zone 155 – stress fractures 207 second tarsometatarsal joint osteoarthritis, see Lisfranc osteoarthritis secondary navicular, see accessory navicular Semmes–Weinstein monofilament 15, 16 sensory testing 15 seronegative spondylarthropathies 219 – complications 222 – differential diagnosis 222 – disorders included in 219 – imaging 220, 220, 221–225 – pathology 219 – predisposing factors 219 – prognosis 222 – symptoms 219 – treatment 222 sesamoid bones 155, 172 sesamoid fractures 164, 172, 174 sesamoid osteoarthritis 172, 174 sesamoid osteonecrosis 172–174, 174 sesamoid pathology 172 – complications 174 – differential diagnosis 174 – imaging 172 – predisposing factor 172 – prognosis 174 – symptoms 172 – treatment 174 sesamoid radiographs 6, – phalangeal fractures 164 sesamoiditis 173 Sever disease, see calcaneal apophysitis short inserts, metatarsal fractures 155 Silfverskiöld disease 148 Silfverskiöld test 16, 17 single-heel-rise test 16 sinus tarsi 120 – fibrovascular reaction, subtalar joint instability 78 sinus tarsi ligaments 120 sinus tarsi syndrome 66, 78, 120 – differential diagnosis 121 – imaging 120 – predisposing factors 120 – prognosis 121 – symptoms 120 – treatment 121 snowboarder’s ankle 55 solid aneurysmal bone cyst (reparative giant cell granuloma) 246 spicule, gout 224 spiral fractures, metatarsals 155 splayfoot deformity 187 sports participation – Achilles tendon rupture 96 – calcaneal apophysitis 89 – calcaneocuboid joint injuries 32 – fifth metatarsal fracture 155 – history-taking 13 – phalangeal fractures 163 – posterior impingement 72 – stress fractures 207 spring ligament 29 spring ligament injury 28 – complications 31 – differential diagnosis 30 – imaging 29 – pathology 29 – prognosis 31 – treatment 31 squeeze test 18 stenosing tenosynovitis 103 stress fractures 207 – bone marrow edema 208 – calcaneal fractures 55 – classification 208 – complications 208 – differential diagnosis 208 – fifth metatarsal 155–156, 159 – imaging 208 – metatarsal fractures 156 – metatarsals 155, 158 – navicular bone 139–141 – pathology 207 – predisposing factors 207 – prognosis 208 – second metatarsal 207 – sites of predilection 207 – symptoms 207 – treatment 208 – types 207 – wavy line appearance 208 stress radiographs – ankle joint 7, –– abnormal signs – calcaneocuboid joint injuries 33 – calcaneocuboid joint instability 149, 150 – hallux valgus 165 – indications – Lisfranc ligament injury 137 – medial ligament injuries 24 Index – navicular fracture 140 – plantar heel spur 180 – spring ligament injury 29 stress tests 19 – ankle instability 76 – syndesmosis 74 subAchilles bursitis 94 subchondral bone osteoarthritis 80 subchondral cysts 51 subchondral radiolucent band, AVN of the talus 86 subperiosteal hematoma, fibula 23, 24 subtalar dislocations 60 – diabetic osteoarthropathy 228, 231 – imaging 61 – treatment 62 subtalar joint – diabetic osteoarthropathy 229 – lateral/medial ankle stability test 17 – posttraumatic degenerative changes 63 – rheumatoid arthritis 215 – sinus tarsi syndrome, see sinus tarsi syndrome subtalar joint instability 77 – complications 79 – differential diagnosis 79 – imaging 78 – pathology 78 – predisposing factors 77 – prognosis 79 – symptoms 77 – treatment 79 subtalar joint sprain 78 subtalar osteoarthritis 79 – complications 81 – differential diagnosis 81 – imaging 79 – pathology 79 – predisposing factors 79 – prognosis 81 – symptoms 79 – treatment 81 Sudeck atrophy, see chronic regional pain syndrome (CRPS) superficial compartment 191 superficial peroneal nerve compression 196 superior peroneal retinaculum 105 superomedial ligament 29 sural nerve compression 196 sural nerve entrapment 159 syndesmosis 26 – instability 74, 75 – parts 26 syndesmosis rupture 26 – differential diagnosis 28 – imaging 27 – pathology 26 – predisposing factors 26 – prognosis/complications 28 – symptoms 26 – tibiofibular fluid pocket vs 28 – treatment 28 synovial chondromatosis, see chondromatosis synovial osteochondromatosis 81 systemic diseases 213 T tailor’s bunion 187 talar fractures 51, 232 – classification 52 – complications 53 – differential diagnosis 53 – imaging 51, 52–55 – pathology 51 – prognosis 53 – structures involved 51 – symptoms 51 – treatment 53 talar osteochondral lesions, see osteochondral lesions of the talus talar rim, abnormal ossification 83 talocalcaneal C sign 90 talocrural joint, see ankle talonavicular joint 63, 139 – instability 149 – osteoarthritis 145, 146 – rheumatoid arthritis 215, 217 talus – avascular necrosis, see avascular necrosis (AVN) of the talus – blood supply 86, 87 – Charcot fractures 229, 232 taping, phalangeal fractures 164 tarsal tunnel syndrome 196, 255 – imaging 197, 199 tarsometatarsal joints 131, 147 – fractures, see Lisfranc fractures – osteoarthritis, see Lisfranc osteoarthritis telangiectatic osteosarcoma 247 tendons, muscle function tests 15, 16 tennis leg 101 tenodesis, ankle instability 77 third metatarsal – fractures 156, 159 – growth zone 155 Thompson squeeze test 16, 17 tibia, diabetic osteoarthropathy 231 tibial artery palpation 16 tibial nerve compression, see tarsal tunnel syndrome tibial pilon fracture 40 – anatomy 41 – classification 41 – complications 42 – differential diagnosis 42 – imaging 42, 46 – pathology 41 – prognosis 42 – symptoms 40 – treatment 42 tibiofibular fluid pocket, syndesmosis rupture vs 28 tibiofibular syndesmosis 26 tiger-stripe pattern, see pediatric bone marrow edema Tillaux fracture 48, 49, 58 – imaging 48 Tillaux–Chaput fractures 35 tiptoe stance, hindfoot inversion 16 toe muscles 15 toe radiographs toe translation test 18 toe(s), Charcot fractures 228 too-many-toes signs 16, 17 traction spur 98 – imaging 98 transitional fractures 58 translation tests 15 transverse arch 131 transverse ligament 26 transverse tarsal joint, see midtarsal joint trimalleolar ankle fracture 34, 42 trimalleolar injury 43 triplane fracture 60 – type I 61 – type II 62 tumorlike lesions 241 tuning fork 15 turf toe 160, 172, 174 two-ligament lateral ankle sprain 21– 22 two-plane fracture 58, 60, 60 U ulcers 228, 228, 235, 235 ultrasound 10, 237 – accessory navicular 115 – accessory ossicles 257 – Achilles tendon insertional tendinopathy 98 – Achilles tendon partial tear 95 – Achilles tendon rupture 96 – achillodynia 94 – ankle fractures 37 – ankle instability 76 – ankle osteoarthritis 79 – anterior impingement 71 – anterior tibial tendinosis 117 – anterior tibial tendon insertional tendinopathy 117 – anterior tibial tendon rupture 119 – anterolateral impingement 69 – anteromedial impingement 71 – aquarium effect 213 – avascular necrosis of the navicular 88 – avascular necrosis of the talus 86 – calcaneal apophysitis 89 – calcaneocuboid joint injuries 33 – chondromatosis 82 – claw toe 168 – coalition 91 – cuboid fracture 142 – cuneiform fractures 144 – diabetic osteoarthropathy 234 – first metatarsophalangeal joint, capsuloligamentous injuries 161 – flexor hallucis longus tendon disorders 104 – fracture of the posterior tibial margin 43 – ganglion cysts 249, 249 – gouty arthropathy 224 – Haglund exostosis 94, 100 – hallucis longus and digitorum longus intersection syndrome 186 – hallux rigidus 166 – hammer toe 168 – hemangioma 247 – high heel spur 94 – intra-articular loose bodies 82 – lateral ligaments injury/trauma 21 – Ledderhose disease 182 – lipoma 243 – Lisfranc fractures 133 – Lisfranc ligament injury 137 – Maisonneuve fractures 46 – mallet toe 168 – medial ligament injuries 24 – metatarsal fractures 156 – metatarsalgia 188 – – – – – – – – – – – Morton neuroma 194 navicular fracture 140 os trigonum syndrome 73 osteochondral lesions of the talus 84 osteoid osteoma 241 osteonecrosis 170 pediatric fractures 59 peroneal brevis muscle 106 peroneal split syndrome 111 peroneal tendon pathology 106 peroneal tendon subluxation/dislocation 109 – pes planovalgus 66 – pigmented villonodular synovitis 250 – plantar fasciitis 178 – plantar fat pad atrophy 183 – plantar heel spur 180 – plantar plate tear 168 – plantar vein thrombosis 185 – positioning 10 – posterior impingement 72 – posterior tibial tendon dysfunction 112 – posteromedial impingement 71 – rheumatoid arthritis 213 – seronegative spondylarthropathies 221 – strengths/weaknesses 10 – stress fractures 208 – subachilles bursitis 94 – subtalar osteoarthritis 79 – syndesmosis rupture 27 – syndesmotic instability 74 – tennis leg 101, 102 – Tillaux fracture 48 – traction spur 98 uric acid crystals 222 uric arthritis, see gouty arthropathy V valgus/varus deformity, ankle osteoarthritis and, see ankle osteoarthritis with varus/valgus deformity variants, normal 255 vertical load 155 Volkmann triangle, see fracture of the posterior tibial margin W walking, vertical load 155 warts, plantar 190, 190 Weber C fractures, ankle 34, 43 weight-bearing radiographs 4, – calcaneocuboid joint injuries 33 – DP (dorsoplantar) projection – indications – lateral view – metatarsalgia 187 – pes cavus 68 – pes planovalgus 66 – positioning – rheumatoid arthritis 213 Z Zwipp classification, calcaneal fractures 56 265 ... with the goal of reconstructing the articular surfaces and the lateral column of the foot With compression fractures of the cuboid, the use of a distractor may be the only way to restore the length... components The dorsal ligament of the Lisfranc complex is the weakest ligament The plantar part of the Lisfranc ligament is twice as thick as the dorsal part The interosseous part is the strongest and. .. attached to the bases of the metatarsals The diaphysis gives attachment to the intrinsic muscles of the foot, and the necks of the metatarsals are interconnected by the intermetatarsal ligaments The