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Journal of the American Academy of Orthopaedic Surgeons 308 Foot fractures account for 5% to 8% of pediatric fractures and approximately 7% of all physeal injuries. 1-4 These fractures are very rare in infants and toddlers due to the large cartilage component of their feet (hence the relative resistance to fracture), but the incidence increases with age. The more elastic and com- pressible nature of cartilage in comparison to bone partly explains why foot fractures are less common in children than in adults. As with most traumatic injuries, pediatric foot fractures occur more commonly in boys than in girls. The child’s foot is generally a for- giving location for fractures. The vast majority of pediatric foot fractures do well with nonoperative management. There are, however, a group of these fractures that may have poor results even with anatomic reduction and internal fixation. A comprehensive understanding of the anatomy of the foot, especially the location and nature of injury to the physes, is requisite for optimal evaluation and treatment of children with these injuries. Anatomy As with other musculoskeletal injuries, a thorough understanding of the relevant anatomy is crucial in the diagnosis and treatment of pediatric foot fractures. The foot can be thought of as consisting of three main subdivisions: the forefoot, the midfoot, and the hindfoot. The forefoot consists of the metatarsals and phalanges. The phalangeal physes are located proximally, but the metatarsal physes are located distally in all but the first metatarsal. The forefoot is separated from the midfoot by the tarsometatarsal (Lisfranc) joint. The tarsometatarsal joints have tremendous intrinsic stability as a result of both the osseous architec- ture and the associated ligamentous structures. The recessed base of the second metatarsal locks between the medial and lateral cuneiforms, limiting medial-lateral translation of the metatarsals. Another anatomic consideration is the trape- zoidal shape of the middle three metatarsal bases, which form a “Roman arch” configuration when they are positioned side by side, affording stability in the sagittal plane. The metatarsals are held together by the transverse metatarsal ligaments distally. In addition, the bases of the lateral four metatarsals are secured by the intermetatarsal ligaments. There is no intermetatarsal ligament between the first and second metatarsals, which can predispose to a medial Lisfranc injury. The Lisfranc ligament, which extends from the medial cuneiform to the base of the second metatarsal, further enhances the stability of these joints. Dr. Kay is Professor of Orthopaedic Surgery, University of Southern California School of Medicine, Los Angeles, and Attending Surgeon, Childrens Hospital Los Angeles, Los Angeles, Calif. Dr. Tang is Resident, Department of Orthopaedic Surgery, University of Southern California, Los Angeles. Reprint requests: Dr. Kay, Childrens Hospital Los Angeles, 4650 Sunset Boulevard, Mailstop 69, Los Angeles, CA 90027. Copyright 2001 by the American Academy of Orthopaedic Surgeons. Abstract Foot fractures account for 5% to 8% of all pediatric fractures and for approximately 7% of all physeal fractures. A thorough understanding of the anatomy of the child’s foot is of central importance when treating these injuries. Due to the difficulties that may be encountered in obtaining an accurate physical examination of a child with a foot injury and the complexities of radiographic evaluation of the immature foot, a high index of suspicion for the presence of a fracture facilitates early and accurate diagnosis. Although the treatment results in pediatric foot trauma are generally good, potential pitfalls in the treatment of Lisfranc fractures, talar neck and body fractures, and lawn mower injuries to the foot must be anticipated and avoided if possible. J Am Acad Orthop Surg 2001;9:308-319 Pediatric Foot Fractures: Evaluation and Treatment Robert M. Kay, MD, and Chris W. Tang, MD Robert M. Kay, MD, and Chris W. Tang, MD Vol 9, No 5, September/October 2001 309 The Chopart transverse mid- tarsal joint separates the midfoot from the hindfoot (talus and calcaneus). The talus is unusual in that a large portion of its surface is articular cartilage. Articulations of the talus include the talar body with the tibial plafond proximally, the inferior surface of the talus with the calcaneal facets plantarly, and the head of the talus with the navicular distally. In contrast to the talus, the calcaneus has numerous muscle and tendon attachments. There are three articulating facets on the superior surface of the calcaneus: a large posterior facet, a concave middle facet, and an anterior facet. Together, these form a complex subtalar joint with the corresponding talar facets. The anterior facet also articulates with the cuboid. The Achilles tendon inserts on the posterior tubercle. The lateral and medial plantar processes serve as points of origin for the plantar fascia and the small muscles of the plantar surface of the foot. The plantar fascia has a thick central fibrous tissue encased by thinner lateral bands. The fascia spreads into five sections distally, each travelling to a toe and strad- dling the flexor tendons. The super- ficial layers are attached to the deep skin fold between the toes and the sole of the foot. There are nine compartments of the foot: the medial and lateral compartments, the three central compartments, and the four interosseous compartments. 5 The medial compartment contains the abductor hallucis and flexor hallucis brevis muscles as well as the tendon of the flexor hallucis longus. The lateral compartment contains the abductor digiti minimi and flexor digiti minimi muscles. The three central compartments contain the flexor digitorum brevis and the four lumbrical muscles, along with the tendons of the flexor digitorum longus in the su- perficial compartment, the adductor hallucis in the adductor compartment, and the quadratus plantae in the calcaneal compartment. The calcaneal compartment is limited to the hindfoot and is confluent with the deep posterior compartment of the leg. Each interosseous compartment contains a plantar and a dorsal interosseous muscle. The timing of the appearance of the ossification centers in the pediatric foot is quite variable. In young children, these ossification centers represent only a small portion of the bone, as a large cartilage anlage is present. The calcaneus, cuboid, and talus are the tarsal bones that are most commonly ossified at the time of birth, with the calcaneus beginning to ossify at around 5 months of gestation, the cuboid at 9 months, and the talus at 8 to 9 months. The phalanges also start ossifying at 2 to 4 months of gestation. The lateral cuneiform starts to ossify 1 year after birth; the medial and middle cuneiforms, at 4 years. The secondary ossification centers for the metatarsals and the phalanges ossify at around 3 years, as does the navicular. The secondary ossification center for the calcaneus is the last to ossify, at 10 years. The presence of one or more of the various accessory ossicles may confound the radiographic diagnosis of a fracture (Fig. 1). The os vesalianum may be mistaken for a fracture of the base of the fifth metatarsal. The os fibulare and os tibiale (located at the lateral border of the cuboid and the proximal medial aspect of the navicular, respectively) are each present in 10% of the population. The os trigonum, located at the posterior lip of the talus, is present in approximately 13% of the population, and is commonly mistaken for an avulsion fracture of the talus. The terminal branches of the anterior and posterior tibial arteries provide the blood supply to the foot. The anterior tibial artery con- tinues as the dorsalis pedis artery, supplies the greater part of the dor- sum of the foot, and provides anas- tomosis with the deep plantar arch and the arcuate artery (which later supplies the dorsal metatarsal artery). The posterior tibial artery divides to become the lateral and medial plantar arteries, with the lateral artery being dominant. The lateral plantar artery also forms the plantar arch, which then gives rise to the plantar metatarsal arteries and common digital arteries. The blood supply to the talus is limited, making it prone to osteonecrosis after a talar neck fracture. 6 The posterior tibial artery gives rise to the artery to the tarsal canal that feeds the deltoid branches, which in turn supply parts of the talar body. The dorsalis pedis artery gives off multiple arterioles that penetrate the superior surface of the head and neck of the talus, as well as the artery of the sinus tarsi. The artery to the tarsal canal and the artery of the sinus tarsi form an anastomotic arch that supplies most of the talus body by retrograde fill. In the child’s foot, there is less dominance of a single arteri- al system with retrograde flow from the neck, which may explain a potentially lower risk of osteonecrosis after talus fractures in children. The posterior tibial nerve gives rise to the medial and lateral plantar nerves. The lateral plantar nerve innervates the intrinsic musculature of the plantar aspect of the foot as well as the adductor hallucis. The lateral plantar nerve also provides sensation to the lateral one and a half toes, analogous to the ulnar nerve distribution in the upper extremity. The medial plantar nerve supplies sensory branches to the medial three and a half toes, simi- lar to the sensory distribution of the median nerve in the upper extremity. Pediatric Foot Fractures Journal of the American Academy of Orthopaedic Surgeons 310 Diagnosis Although most pediatric foot fractures are isolated injuries, some occur in polytrauma patients, war- ranting serial examinations. In one series, 21 (17%) of 125 patients with pediatric ankle and foot injuries had other skeletal injuries as well. 7 Patients with massive soft-tissue injury present special challenges. A careful neurovascular examination is essential, but often difficult in a frightened, uncooperative child. Palpation of pulses and assessment of capillary refill are important. Doppler evaluation of a child with a pulseless foot is often necessary. Noxious stimuli, including needle sticks, can be used to help assess sensation in the child who will not cooperate with evaluation of light touch sensation distal to the injury. As in adults, compartment syn- dromes may occur after crush or other high-energy injuries. 8 Affected feet are quite swollen and generally very painful. Compartment pres- sure measurements are invaluable in the assessment of a child with a suspected compartment syndrome, especially one who is obtunded and has significant swelling of a foot associated with a fracture. Fasciotomy should be performed if compartment pressures exceed 30 mm Hg. Anteroposterior (AP), lateral, and oblique radiographs are most commonly utilized to assess patients with foot trauma. The oblique radiographs are necessary to supplement the AP and lateral views because of the significant osseous overlap on the lateral view. Other specialized views and/or computed tomographic (CT) and magnetic resonance (MR) imaging studies may be necessary to com- pletely evaluate specific fracture con- figurations. Comparison views are rarely necessary for the orthopaedist familiar with the normal radiographic appearance. 9 Fractures and Dislocations of the Talus Fewer than 1% of all pediatric fractures and only 2% of all pediatric foot fractures are talus fractures. 1,10 Os cuboideum secundarium, 1% Os tibiale externum, 10% Os tibiale externum, 10% Os intercuneiforme Os sustentaculum, 5% Talus secundarius Os trigonum, 13% Calcaneus secundarius, 4% Os intercuneiforme Os intermetatarseum, 9% Os vesalianum Os peroneum Pars fibularis ossis metatarsalis I Os peroneum Os vesalianum A B C Figure 1 Accessory ossifications in the foot and their frequency of occurrence (if data are available). (Adapted with permission from Tachdjian MO [ed]: Pediatric Orthopedics, 2nd ed. Philadelphia: WB Saunders, 1990, p 471.) Robert M. Kay, MD, and Chris W. Tang, MD Vol 9, No 5, September/October 2001 311 In a series of 90 pediatric talus fractures, there were 50 avulsion fractures (56%), 18 osteochondral lesions (20%), 17 talar neck fractures (19%), and 5 talar body fractures (6%). 11 Avulsion fractures require only symptomatic treatment, often with a short leg splint or short walking cast for 1 to 2 weeks until symptoms subside. There are generally no long-term sequelae. As in adults, talar neck and body fractures result from forceful dorsiflexion of the ankle. However, in reported series dealing with children, the mechanism of injury was a fall from a height or a motor vehicle accident in approximately 70% to 90% of cases. 11,12 Of all talar neck and body fractures, only 10% occur in children. 13 These fractures occur throughout childhood and have even been reported in children less than 2 years old. 11,12 Jensen et al 11 reported that 6 (43%) of the 14 patients in their series of pediatric talar neck and body fractures had associated fractures. Signs and symptoms of talar fractures include ankle or hindfoot pain, local tenderness, and pain with ankle dorsiflexion. Local swelling is variable. Plain radiographs frequently delineate the fracture line and the amount of displacement, although they may be read as normal initially. 12 Computed tomography may aid in the assessment of fracture configuration and displacement. The Hawkins classification system is most commonly used for classifying talar neck fractures in children as well as in adults. 14,15 Type I fractures are nondisplaced (Fig. 2). Type II fractures are displaced talar neck fractures in conjunction with subluxation or dislocation of the subtalar joint. Type III fractures are displaced talar neck fractures in conjunction with subluxation or dislocation of both the subtalar and the tibiotalar joint. The extremely rare type IV injuries are characterized by a displaced talar neck fracture, subluxation of the head of the talus from the talonavicular joint, and subluxation or dislocation of the subtalar and/or ankle joints. Osteonecrosis of the talar body is common after fractures of the talar neck and body due to disruption of the vascular ring surrounding the talar neck as the fracture displaces. Because the surface of the talus is mostly articular cartilage, the talar blood supply is tenuous. Overall, the risk of osteonecrosis in reported series of talar neck fractures that combine adult and pediatric patients is approximately 50%, and is highest for type III and IV fractures and low- est for type I fractures. In one such series, Canale and Kelly 16 reported osteonecrosis in 15% of type I fractures, 50% of type II fractures, and 84% of type III fractures. In another series, Jensen et al 11 reported no cases of osteonecrosis in 10 fractures Figure 2 AP (A) and lateral (B) radiographs of a minimally displaced talar neck fracture (arrows) in a 4-year-old boy who sustained ipsilateral fractures of the distal tibial physis and distal fibular diaphysis. C, CT scan confirms minimal displacement. Fracture comminution is evident. (Courtesy of J. Dominic Femino, MD.) A B C Pediatric Foot Fractures Journal of the American Academy of Orthopaedic Surgeons 312 (3 of which were displaced). Letts and Gibeault 12 reported 3 cases of osteonecrosis in 13 nondisplaced pediatric talar neck fractures (incidence of 23%). The Hawkins sign (lucency in the subchondral bone of the talar dome, usually seen by 8 weeks after injury) suggests that the talar body is adequately vascularized and the risk of osteonecrosis is low. Technetium bone scanning and, more commonly, MR imaging can be useful to assess the presence of osteonecrosis in borderline cases. Treatment of nondisplaced talar neck and body fractures consists of immobilization in a non-weight- bearing long leg cast. After approximately 2 months, a patient with a positive Hawkins sign (indicating that there is no osteonecrosis) may begin weight bearing as tolerated. A closed reduction should be attempted for displaced talar fractures, although the criteria for an acceptable reduction have not been clearly defined. In general, however, the surgeon should attempt to achieve an intra-articular reduction with less than 2 mm of residual displacement. These fractures are often stable with the foot in a plantar- flexed position. If open reduction and internal fixation is performed, insertion of screws into the talus from posterior to anterior has been shown to be biomechanically superior to insertion from anterior to posterior. 17 Long-term follow-up suggests that pain is common after displaced talar fractures in children. 11 Whether this pain is due to the initial high- energy injury and associated chon- dral damage or to residual intra- articular incongruity is unclear. 11 Follow-up radiographic studies have demonstrated the development of arthrosis in the ankle joints, but not the subtalar joints, of patients with displaced talar fractures. 11 The duration of protected weight bearing for patients with osteonecrosis remains controversial. Vari- ous mechanisms of unloading the talus have been tried, including the use of ambulatory aids, bracing, and casting. Letts and Gibeault 12 reported on three pediatric patients with osteonecrosis after talar neck fractures. Talar flattening and ankle stiffness developed in two patients after bearing weight on the affected extremity (due to a delay in diagnosis). The patient whose weight bearing was limited until the osteone- crotic segment had healed did not have such complications. Even when weight bearing is not recommended, the long-term effect and the influence of patient compliance on outcome are unclear. Peritalar dislocations are defined as dislocations of the subtalar joint and talonavicular joint in the absence of a talar fracture. These injuries are rare, accounting for only 4% of all pediatric talar fractures and dislocations. 18 These are generally high-energy injuries and were associated with ipsilateral foot fractures in all 5 patients in the series of Dimentberg and Rosman. 18 Closed reduction is generally feasible, but may be impossible if diagnosis is delayed or if there are interposed soft-tissue or osseous structures. Osteochondritis Dissecans of the Talus The talus is the second most common site for osteochondritis dissecans (OCD). Osteochondritis dissecans of the talus is analogous to that found in other anatomic locations and is characterized by necrotic bone underlying articular cartilage. In the talus, OCD usually occurs either anterolaterally or posteromedially. Children with OCD of the talus may present with the acute onset of pain after a traumatic incident (such as an inversion injury) or with chron- ic ankle pain. Trauma to the ankle has been reported in 46% to 63% of children with OCD of the talus. 19,20 The mean age of children with OCD of the talus is 13 to 14 years, although it may be seen in children less than 10 years old. 19,20 Signs and symptoms in the affected ankle may include pain, swelling, instability, repetitive sprains, and decreased range of motion. In one series, 20 the average duration of symptoms prior to diagnosis was 4.3 months. Locking of the ankle joint is rarely reported. Physical examination usually demonstrates decreased range of motion of the ankle, which is often painful. Localized tenderness may be difficult to elicit, and the presence of synovitis is variable. Grading of OCD of the talus is based on the system described by Berndt and Harty in 1959. 21 Type I lesions are nondisplaced. Type II lesions are partially detached. Type III lesions are detached but not displaced. Type IV lesions are detached and displaced or rotated. Plain radiographs will often demonstrate a tri- angular sclerotic fragment separated from the talar dome anterolaterally or posteromedially (Fig. 3). Some- times, these lesions are hard to visu- alize on plain films, depending on their location in the sagittal plane. Magnetic resonance imaging is the most helpful radiologic study for assessing OCD of the talus. 22 This modality can help delineate the condition of the articular cartilage, whether the articular cartilage is intact, the extent of the lesion, the extent of sclerosis of the fragment, and whether the fragment is displaced. Evidence of fluid under- neath the OCD fragment indicates disruption of the articular cartilage. The MR study should be used in conjunction with plain radiographs to classify these lesions. The course of OCD of the talus appears to be more benign in children than in adults. Bauer et al 23 reported on five children with OCD of the talus followed up for an aver- Robert M. Kay, MD, and Chris W. Tang, MD Vol 9, No 5, September/October 2001 313 age of 22 years: four of the lesions regressed, the fifth did not progress, and no patient had radiographic evidence of osteoarthritis at long- term follow-up. The results of surgical treatment also appear to be better in children than in adults. 19,23 Nonoperative management has been recommended as the initial treatment of choice for all but type IV lesions, 19,20 generally beginning with immobilization and protected weight bearing for 1 to 2 months. Activity modification and protected weight bearing may continue for an additional 2 to 3 months. If there is no symptomatic and radiographic improvement by 3 to 4 months, drilling, debridement, or arthroscopic fixation may be indicated. Greenspoon and Rosman 24 reported that the results of bone grafting were better than the results of OCD fragment excision. Arthrotomy with a medial malleolar osteotomy has been used in various series, but often can be avoided owing to ad- vances in arthroscopic technique. Type IV lesions should be treated operatively. Calcaneal Fractures Approximately 5% of all patients with calcaneal fractures are children 25 ; however, calcaneal fractures represent only 2% of pediatric foot injuries. 10 Boys are more commonly affected than girls. Extra-articular fractures are more frequent in children than in adults, representing 65% of pediatric calcaneal fractures. 25,26 Fifty percent of pediatric calcaneal injuries that occur after falls result in intra-articular fractures. In adolescents 15 years and older, the fracture patterns are com- parable to those seen in adults. 25 The mechanism of most calcaneal fractures is axial loading, with the talus being driven into the calcaneus. The fracture is most commonly due to a fall from a height or a motor vehicle accident (incidence rates of 40% and 15%, respectively, in two studies 25,26 ). Because these injuries generally are the result of high-energy trauma, associated injuries are common, occurring in approximately one third of children with calcaneal fractures. These may be lacerations of the ipsilateral lower extremity 25,26 or even spine fractures (5% of the children in one study 25 ). In an early series before the advent of CT and MR imaging, 26% of calcaneal fractures were missed initially. 25 A plain-radiographic study should include AP, lateral, and axial views. Oblique calcaneal views may also aid in the initial assessment of fracture configuration. The lateral view is important because it allows measure- ment of the Böhler’s angle (Fig. 4). Böhler’s angle normally measures 25 to 40 degrees in adults, but is less in children. 14 The “crucial angle of Gisanne” is rarely measured in children because a large portion of the calcaneus is not yet ossified. The angle usually measures 125 to 140 degrees in adolescents. A CT scan may also be valuable in assessing the A B C Figure 3 AP (A) and lateral (B) radiographs of a 14-year-old boy with a 1-year history of ankle stiffness after an inversion ankle injury demonstrate a large osteochondral lesion (arrows) of the anterolateral talar dome. At the time of presentation, the patient was fully active and denied pain. C, CT scan demonstrates a type III lesion and significant sclerosis of the osteochondral fragment. Observation was undertaken because of the minimal symptoms. Pediatric Foot Fractures Journal of the American Academy of Orthopaedic Surgeons 314 configuration of an intra-articular fracture. There are several classification sys- tems for calcaneal fractures. The Essex-Lopresti method is widely used. This system categorizes injuries as tongue-type or split-depression fractures, but the most important dif- ferentiation is between intra-articular (Fig. 5) and extra-articular fractures. Extra-articular fractures can be treated with a bulky Jones dressing followed by weight bearing in 3 to 4 weeks. The long-term sequelae of such fractures are rare, although there may be some residual loss of heel height and widening of the heel. Some authors advocate surgical treatment for displaced intra-articular fractures in young patients. How- ever, Schantz and Rasmussen 27 reported good results in pediatric patients treated nonoperatively. Thomas 28 reported good results even in patients with a decreased Böhler’s angle who were treated nonoperatively; these results were thought to be secondary to potential talar re- modeling in the pediatric population. Although the optimal treatment for younger patients remains controversial, open reduction and internal fixation is indicated for displaced intra- articular calcaneal fractures in adolescents, as it is in adults. Other Tarsal Fractures Tarsal fractures account for approximately 1% of all pediatric fractures. 1 Fractures of the navicular, cuboid, and cuneiforms are reported to represent 2% to 7% of pediatric foot injuries. 10,29 Most tarsal fractures are avulsion or stress fractures, both of which can be treated in a short walking cast for 2 to 3 weeks. This is sufficient to allow healing, and no long-term sequelae need be expected. Complete displaced fractures of the navicular, cuneiforms, and cuboid often result from high-energy trauma; therefore, associated injuries, such as those of the Lisfranc complex, are common. Because much of the surface of these bones is intra- articular, closed or open reduction and internal fixation may be needed for displaced fractures. Assessment of the soft-tissue envelope is important in these high-energy injuries, and compartment syndrome must be ruled out. Lisfranc Injuries Injuries of the tarsometatarsal joint complex are uncommon in children. The mechanism of injury is either forceful plantar-flexion of the foot, generally with axial loading, or a direct crush injury. Falls from a height accounted for approximately 60% of the pediatric Lisfranc injuries in the two largest series. 30,31 Of the 34 patients in those studies, 21 (62%) were boys. The age range in the two studies differed consider- ably: Johnson 30 reported that the fracture occurred most commonly in children aged 3 to 6 years, but Wiley 31 reported a mean patient age of 12 years. Johnson reported fractures of the proximal first metatarsal in all 16 of his patients, including 1 with a concomitant second metatarsal fracture. Ligamentous injury may accom- pany fractures as the Lisfranc joint complex is loaded. Because the plantar ligaments of the tarsometatarsal joint complex are stronger than the dorsal ligaments, the dorsal ligaments rupture first. With continued Figure 5 Lateral radiograph demonstrates a minimally displaced intra-articular calcaneal fracture (split-depression type) in a 4-year-old boy involved in a motor vehicle accident. Associated injuries included an ipsilateral femoral shaft fracture, contralateral distal femoral physeal fracture, and a degloving injury to the contralateral leg. Care for the calcaneal fracture consisted of initial splinting and a 3-week non-weight- bearing period. The dotted lines indicate the fracture pattern. Figure 4 Lateral view of the calcaneus depicts Bohler’s angle and Gissane’s angle. Böhler’s angle is defined as the angle between two lines as seen on the lateral view: the first connects the superior portion of the anterior and posterior calcaneal facets, and the second connects the superior portions of the posterior facet and the tuberosity. (Adapted with permission from Heckman JD: Fractures and dislocations of the foot, in Rockwood CA, Green DP, Bucholz RW, Heckman JD [eds]: Rockwood and Green’s Fractures in Adults, 4th ed. Philadelphia: Raven Publishers, 1996, p 2326.) Böhler’s angle Lateral process Navicular Talus Cuboid Calcaneus Crucial angle of Gissane Robert M. Kay, MD, and Chris W. Tang, MD Vol 9, No 5, September/October 2001 315 loading, the plantar ligaments then rupture, after which plantar displacement of the metatarsal bases may occur. Children who sustain Lisfranc injuries due to high-energy trauma often have significant soft-tissue injury and should be admitted to the hospital for observation overnight. Compartment syndrome may be her- alded by pain out of proportion to the injury, as well as pain with pas- sive motion of the toes in the awake patient. Compartment pressures must be measured if there is the pos- sibility of a compartment syndrome in any patient, regardless of cognitive status. In patients with altered men- tal status, the physician should be more inclined to measure compartment pressures, as clinical signs of pain may not be easily appreciated in the obtunded patient. Fasciotomy of all compartments of the foot should be performed if compartment pressures are greater than 30 mm Hg. 5,8 Lisfranc injuries may involve the entire tarsometatarsal complex or any portion thereof. Diastasis frequently occurs between the bases of the first and second metatarsals, as there is no intermetatarsal ligament in that interval (Fig. 6). Alterna- tively, all five rays may be involved, either with all rays displacing in the same direction (homolateral injury) or with the first ray displacing me- dially and the lateral four rays displacing laterally (divergent injury). 32 The initial radiographic evaluation should consist of AP, oblique, and lateral radiographs. If possible, the AP and lateral films should be weight-bearing views, as subtle injuries may not be evident on non- weight-bearing radiographs. 33 Frac- tures of the base of the first metatarsal are common, but an isolated fracture of the base of the second metatarsal may result from avulsion of the insertion of the Lisfranc ligament, heralding the presence of an injury to the Lisfranc complex. If no fracture is evident on presentation, the medial aspect of the base of the second metatarsal should line up with the medial aspect of the middle cuneiform, and the medial aspect of the base of the fourth metatarsal should line up with the medial aspect of the cuboid. Nondisplaced fractures at the level of the tarsometatarsal joint complex may actually be injuries that were initially displaced but then spontaneously reduced. Patients with such injuries may be treated with a bulky dressing or posterior plaster splint for several days to 1 week, followed by a non-weight- bearing short leg cast until 1 month after injury, and then a short walking cast for an additional 2 weeks. Patients with Lisfranc fracture- dislocations should be treated operatively. Closed reduction should be attempted in the operating room. Wiley 31 reported that 7 (39%) of 18 patients in his series required closed reduction. Finger traps placed on the toes facilitate reduction. If closed reduction is possible, internal fixation should be performed. Kirschner wires may be used in young children. Cannulated screws are pre- ferred for the older child with sufficient bone stock for screw fixation. If a nearly anatomic closed reduction is not possible, open reduction should be performed, with removal of any impediments to reduction (frequently osteocartilaginous fracture frag- ments), followed by internal fixation. The long-term results in children with Lisfranc injuries are uncertain. Even with short-term follow-up, Wiley reported residual pain at the Lisfranc joint in 4 (22%) of his 18 patients. Metatarsal Fractures Metatarsal physeal fractures represent 1% to 2% of all physeal injuries Figure 6 AP radiographs of both the uninjured left foot (A) and the injured right foot (B) of a 6-year-old boy whose right foot had been run over by a car the previous day. Diastasis is evident between the first and second rays proximally and distally in the right foot. Although the medial column is disrupted, the remainder of the Lisfranc complex is appropriately aligned. The patient underwent open reduction and pinning after an unsuc- cessful attempt at closed reduction in the operating room. A B Pediatric Foot Fractures Journal of the American Academy of Orthopaedic Surgeons 316 in children and adolescents. 1-3 In one large series, metatarsal fractures accounted for approximately 60% of pediatric foot fractures, with fractures of the base of the fifth metatarsal accounting for 22%. 10 Owen et al 29 reported that first-metatarsal fractures accounted for 73% of all tarsal and metatarsal fractures in children younger than 5 years, but only 12% of such fractures in children older than 5. In the same series, 6.5% of all fractures and 20% of all first-metatarsal fractures were initially unrecognized by the treating physician. The mechanism of metatarsal fracture may be either indirect or direct. Indirect injuries often result from axial loading, inversion, rotation, or a combination thereof (Fig. 7). Direct injuries often result from the impact of falling objects or crush injuries. If these fractures occur proximally rather than in the midshaft, evaluation of the tarsometatarsal joint complex for concomitant injury is important. Radiographs should consist of AP, lateral, and oblique views to assess fracture alignment. Medial- lateral displacement of the fracture may be seen, but is acceptable in the absence of displacement of the Lis- franc complex. If these fractures are not proximal, they can almost always be treated with weight bearing as tolerated in a short walking cast or a cast shoe. The duration of treatment is generally 3 weeks (until tenderness at the fracture site has subsided). In children with marked swelling, a circumferential cast should not be applied at the time of evaluation, and consideration should be given to admitting the child for overnight observation. Compartment syn- dromes, though rare, may occur if high-energy trauma has caused multiple metatarsal fractures. In the rare instance in which there is marked sagittal malalign- ment of the metatarsal heads, closed reduction and pinning of a metatarsal fracture should be considered to avoid transfer lesions in the future. Finger traps are often helpful in re- ducing such fractures. Growth disturbance may occur as a result of a metatarsal fracture. Physeal fractures of the base of the first metatarsal may potentially cause a growth disturbance and shortening of the first ray. This com- plication is rare, but may result in transfer lesions. Overgrowth may also occur after metatarsal fractures. Fractures of the Base of the Fifth Metatarsal Approximately 40% of all metatarsal fractures are fractures of the base of the fifth metatarsal. In one large series, 10 as many as 22% of pediatric foot fractures were at that site. In that same series, 90% of fifth-metatarsal fractures occurred in children older than 10 years. As in adults, the location of the fracture, the fracture appearance, and the duration of symptoms before presentation are important prog- nostic factors. The injury generally occurs with the foot in a weight- bearing position. Inversion has been reported as the most common mechanism of injury. 29 The initial radiographic examination should consist of AP, lateral, and oblique views. The location of the fracture is important to both prognosis and treatment. Tuber- osity fractures are generally benign and heal with 6 weeks in a short walking cast. Although previously thought to be due to avulsion at the insertion of the peroneus brevis, tuberosity fractures now appear to be due to avulsion at the origin of the abductor digiti minimi. Frac- tures at or distal to the metaphyseal- diaphyseal junction are more recal- citrant to treatment. These fractures should be treated with at least 6 weeks in a non-weight-bearing cast. If the fracture is preceded by weeks to months of pain (or if there is radiographic evidence of a preceding stress injury), internal fixation should be considered. Some authors advocate curettage and bone grafting in patients with intramedullary sclerosis indicative of a delayed union or nonunion. 34,35 Phalangeal Fractures Phalangeal fractures are common in the pediatric population and often do not even result in the child being seen by an orthopaedic surgeon. Many of these fractures are treated symptomatically by the patient and family or by the primary- care physician. Phalangeal fractures may account for as many as 18% of pediatric foot fractures. 10 In three studies, 1-3 phalangeal fractures rep- resented 3% to 7% of all physeal Figure 7 Displaced third- and fourth- metatarsal fractures and a nondisplaced second-metatarsal fracture sustained by a 15-year-old boy due to an indirect mechanism of injury. The patient was treated in a short walking cast for 2 weeks, followed by a cast boot for 2 additional weeks. Robert M. Kay, MD, and Chris W. Tang, MD Vol 9, No 5, September/October 2001 317 fractures and were usually Salter- Harris type I or type II injuries. The examining physician must closely evaluate the toe for integrity of the skin and also make sure that there is not a nail-bed injury. Open fractures require irrigation and debridement and intravenous antibiotic therapy (Fig. 8). Nail-bed injuries involving the germinal matrix should be repaired. Closed fractures rarely require reduction. Buddy-taping of the toes with weight bearing as tolerated almost universally results in a well- healed and well-aligned fracture within 3 to 4 weeks. (A hard-soled shoe may be used for patient comfort until fracture healing has occurred.) Closed versus open reduction and pinning should be considered for markedly angulated fractures or displaced intra-articular fractures of the proximal phalanx of the great toe (including Salter-Harris type III and type IV fractures) involving more than 25% of the joint surface and those with more than 2 mm of displacement. Growth arrest and stiffness are uncommon sequelae of phalangeal fractures. When growth arrest occurs, it most commonly follows fractures of the great toe. Lawn Mower Injuries Lawn mowers have been reported to cause as many as 160,000 injuries annually, including approximately 2,000 that result in permanent im- pairment in children. 36-38 Accidents occur with all types of mowers, but the most severe injuries usually occur when young children are struck by riding mowers. In fact, as many as 72% of children who sustain severe lawn mower injuries are bystanders. 37,38 A careful evaluation of the entire child, including all extremities, is vital. In a study of 33 children with lawn mower injuries, Alonso and Sanchez 36 found that 8 (24%) had head and eye injuries, 12 (36%) had upper-extremity injuries, and 13 (39%) had lower-extremity injuries. Fractures must be evaluated in conjunction with the degree of soft- tissue damage and the integrity of neurovascular structures. These are high-energy injuries that frequently involve significant soft-tissue and fracture contamina- tion. Initial treatment should consist of irrigation and debridement and triple-antibiotic coverage. Internal fixation of fractures and/or external fixation spanning the injured segment may help stabilize the soft tis- sues, allow access to the zone of injury, and facilitate patient care. Repeat debridements should be performed at 2- to 3-day intervals until the wound is sufficiently clean. Soft-tissue damage from lawn mower injuries is extensive, and the soft-tissue envelope generally appears better on presentation than it does in the ensuing days due to the initial compromised soft-tissue per- fusion. Early involvement of the plastic surgery team is important to facilitate coverage of these wounds by 7 to 14 days after injury. Skin grafting or flap coverage is needed in more than 50% of patients. 37 Un- like adults, children may do well with split-thickness skin grafts placed on the plantar aspect of the foot. 38 Despite appropriate early care, amputation rates in children with lower-extremity lawn mower injuries have ranged from 16% to 78%. 36-38 Even in salvaged extremities, late deformity may occur due to muscle imbalance resulting from the damage or loss of muscles, tendons, or nerves at the time of injury. Occult Foot Fractures Toddlers often present with the acute onset of a limp but without a definite trauma history. Unlike a “toddler’s fracture,” there may be no tenderness over the tibia. Tender- ness is often evident in the foot, but may be hard to pinpoint. Typically, a child with an occult foot fracture will be able to crawl without diffi- culty but will limp when walking. Plain radiographs will rarely reveal a fracture. A bone scan, how- Figure 8 AP (left) and lateral (above) radiographs of a 12- year-old boy after an open Salter-Harris type II fracture of the distal phalanx of the great toe. The open fracture was not recognized on initial presentation. When the patient presented to the author’s institution, purulent drainage and cellulitis were evident. Treatment consisted of irrigation and debridement, followed by open reduction and percuta- neous pinning of the fracture. (Courtesy of Richard A. K. Reynolds, MD, Los Angeles, Calif.) [...]... Drummond DS: Major lower extremity lawn mower injuries in children J Pediatr Orthop 1995;15:78-82 38 Vosburgh CL, Gruel CR, Herndon WA, Sullivan JA: Lawn mower injuries of the pediatric foot and ankle: Observations on prevention and management J Pediatr Orthop 1995;15:504-509 39 Englaro EE, Gelfand MJ, Paltiel HJ: Bone scintigraphy in preschool children with lower extremity pain of unknown origin J... injuries and other high-energy foot injuries When a compartment syndrome is present, decompression of all compartments of the foot should be performed emergently to minimize morbidity das JC, Darling DB, Bankoff MS, Swan CS II: Comparison views in extremity injury in children: An efficacy study Radiology 1979;131:95-97 Crawford AH: Fractures and dislocations of the foot and ankle, in Green NE, Swiontkowski... management of osteochondral lesions of the talus: Results of drilling and usefulness of magnetic resonance imaging before and after treatment Arthroscopy 2000; 16:299-304 Bauer M, Jonsson K, Lindén B: Osteochondritis dissecans of the ankle: A 20year follow-up study J Bone Joint Surg Br 1987;69:93-96 Greenspoon J, Rosman M: Medial osteochondritis of the talus in children: Review and new surgical management... September/October 2001 classification and treatment J Bone Joint Surg Br 1982;64:349-356 33 Shapiro MS, Wascher DC, Finerman GAM: Rupture of Lisfranc’s ligament in athletes Am J Sports Med 1994;22: 687-691 34 Torg JS, Balduini FC, Zelko RR, Pavlov H, Peff TC, Das M: Fractures of the base of the fifth metatarsal distal to the tuberosity: Classification and guidelines for non-surgical and surgical management... with lowerextremity pain or limping of unknown origin had abnormal tracer uptake localized to the foot on bone scans Of those 16 patients, 9 had abnormal uptake in the cuboid; 4, in the calcaneus; 2, in multiple tarsal bones; and 1, in the tibiotalar joint If an occult foot fracture is suspected, a short walking cast can be used for 2 to 3 weeks Repeat radiographs at the time of cast removal will often... Compartment syndrome of the foot in children J Bone Joint Surg Am 1995;77:356-361 9 McCauley RGK, Schwartz AM, Leoni- 318 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Journal of the American Academy of Orthopaedic Surgeons Robert M Kay, MD, and Chris W Tang, MD 27 Schantz K, Rasmussen F: Good prognosis after calcaneal fracture in childhood Acta Orthop Scand 1988;59:560-563 28 Thomas HM: Calcaneal... for 2 to 3 weeks Repeat radiographs at the time of cast removal will often reveal callus formation and confirm the diagnosis of occult fracture If symptoms persist after casting and radiographs do not demonstrate callus formation, a bone scan is indicated to identify the site of injury Pediatric foot fractures often differ significantly from foot fractures in adults with regard to frequency, fracture... Peterson HA: Analysis of the incidence of injuries to the epiphyseal growth plate J Trauma 1972; 12:275-281 3 Peterson HA, Madhok R, Benson JT, Ilstrup DM, Melton LJ III: Physeal fractures: Part 1 Epidemiology in Olmsted County, Minnesota, 1979–1988 J Pediatr Orthop 1994;14:423-430 4 Worlock P, Stower M: Fracture patterns in Nottingham children J Pediatr Orthop 1986;6:656-660 5 Manoli A II, Weber TG: . scan confirms minimal displacement. Fracture comminution is evident. (Courtesy of J. Dominic Femino, MD.) A B C Pediatric Foot Fractures Journal of the American Academy of Orthopaedic Surgeons 312 (3. upper extremity. The medial plantar nerve supplies sensory branches to the medial three and a half toes, simi- lar to the sensory distribution of the median nerve in the upper extremity. Pediatric. displacement, although they may be read as normal initially. 12 Computed tomography may aid in the assessment of fracture configuration and displacement. The Hawkins classification system

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