Journal of the American Academy of Orthopaedic Surgeons 192 Rupture of the quadriceps tendon is a relatively infrequent but serious injury requiring prompt diagnosis and treatment. 1-4 It is more com- mon in patients older than 40 years and often is associated with under- lying medical conditions. 1 The first written description of quadriceps tendon injury is credited to Galen, who described it in a young wres- tler. 5,6 Even after prolonged heal- ing, the athlete was unable to ex- tend his knee and had difficulty walking on inclined surfaces. Quadriceps tendon rupture may result from either indirect or direct mechanisms. Clinical findings typi- cally include the triad of acute pain, inability to actively extend the knee, and a suprapatellar gap. 7-9 Various imaging modalities, such as plain radiographs, ultrasound, and mag- netic resonance imaging (MRI), may be used to evaluate quadriceps tendon injury. A spectrum of path- ology exists that can affect the quadriceps tendon, including (1) incomplete rupture, (2) acute uni- lateral rupture, (3) bilateral rupture, and (4) tendinosis, or so-called jumper’s knee. Incomplete or partial quadriceps tendon ruptures and jumper’s knee are usually treated nonsurgically. 10 Complete tendon rupture requires surgical repair for optimal results, and several techniques have been described. Neglected or chronic ruptures of the quadriceps tendon present a difficult problem and can result in substantial disability for the patient. More complex reconstruc- tive procedures may be necessary to repair the extensor mechanism in these cases, and good results have been reported in some series. Anatomy The quadriceps tendon is a coales- cence of the tendinous portions of the rectus femoris, vastus inter- medius, vastus lateralis, and vastus medialis muscles (the quadriceps). The muscle fibers from the quadri- ceps blend with its tendinous por- tion approximately 3 cm proximal to the superior border of the patella. The rectus femoris is the most ante- rior muscle and originates from the anteroinferior iliac spine and hip capsule, then inserts into the superi- or border of the patella. It continues distally over the anterior surface of the patella, becoming contiguous with the fibers of the patella tendon. The rectus femoris is unique among the quadriceps muscles in that it also crosses the hip joint. Deep to the rectus femoris is the vastus intermedius, which originates at the anterior midfemur and inserts into the superior border of the patella. The vastus lateralis lies anterior and lateral to the vastus intermedius and originates in the femur directly below the greater trochanter and along the linea aspera. The vastus lateralis has a long tendinous inser- tion at the superolateral patellar border. The vastus medialis origi- nates at the anterior femur just below the level of the lesser tro- chanter, extends inferiorly, and inserts at the superomedial border of the patella. Aponeurotic fibers Dr. Ilan is Chief Resident, Department of Orthopaedic Surgery, NYU–Hospital for Joint Diseases, New York, NY. Dr. Tejwani is Assistant Professor, Department of Orthopaedic Surgery, NYU–Hospital for Joint Diseases. Dr. Keschner is Chief Resident, Department of Orthopaedic Surgery, NYU–Hospital for Joint Diseases. Dr. Leibman is Resident, Department of Orthopaedic Surgery, NYU–Hospital for Joint Diseases. Reprint requests: Dr. Tejwani, 301 East 17th Street, New York, NY 10003. Copyright 2003 by the American Academy of Orthopaedic Surgeons. Abstract Rupture of the quadriceps tendon is an uncommon yet serious injury requiring prompt diagnosis and early surgical management. It is more common in older (>40 years) individuals and sometimes is associated with underlying medical conditions. In particular, bilateral spontaneous rupture may be associated with gout, diabetes, or use of steroids. Clinical findings typically include the triad of acute pain, impaired knee extension, and a suprapatellar gap. Imaging studies are useful in confirming the diagnosis. Although incomplete tears may be man- aged nonsurgically, complete ruptures are best treated with early surgical repair. J Am Acad Orthop Surg 2003;11:192-200 Quadriceps Tendon Rupture Doron I. Ilan, MD, Nirmal Tejwani, MD, Mitchell Keschner, MD, and Matthew Leibman, MD Doron I. Ilan, MD, et al Vol 11, No 3, May/June 2003 193 from both the vastus lateralis and medialis contribute to the lateral and medial retinacula, respectively. 1,11 The articularis genu muscle, an anatomic variant, occasionally con- tributes fibers to the quadriceps ten- don. This muscle arises deep to the vastus intermedius, originating on the distal anterior femoral diaphysis and inserting into the superior cap- sule. 11 The quadriceps is innervated by the femoral nerve (L2-4). The four muscles that form the quadriceps unite into one common tendon that incorporates the patella. This tendinous insertion is com- posed of three distinct planes. The superficial, or anterior, plane con- tains the rectus femoris; the second, or middle, plane contains the vastus lateralis and medialis; the third, or deep, plane contains the vastus in- termedius. Deep to these layers is the synovium, which, when torn, accounts for the large hemarthrosis associated with quadriceps tendon rupture. 1 Biomechanics The extensor mechanism is com- posed of the quadriceps tendon, patella, and patellar tendon. During active knee extension, forces gen- erated in the quadriceps muscle group are transferred in a conver- gent fashion via the patellar tendon and retinacula to the tibial tubercle. The anterior location of the patella enables it to act as a fulcrum, which increases the lever arm of the quad- riceps (the distance between the joint center of rotation and the quadriceps mechanism). 11 The transmission of force from the quadriceps to the patellar tendon is complex. The relative force in each tendon varies with the degree of knee flexion and is modulated by the ability of the patella to tilt in the sagittal plane. Huberti et al 12 dem- onstrated increased forces on the quadriceps tendon in relation to the patellar tendon at increasing knee flexion angles. The force in the quadriceps is 30% less than the force in the patellar tendon at a knee flex- ion angle of 30°, whereas the forces are equal at 50° of flexion. At these flexion angles, the patellofemoral contact area is located at the distal end of the patella, giving the quadri- ceps tendon a mechanical advantage during active knee extension. As the knee is flexed beyond 90°, the force in the quadriceps tendon is 30% greater than the force in the patellar tendon. The patellofemoral contact area shifts proximally with increas- ing knee flexion, giving the patellar tendon a mechanical advantage dur- ing active knee extension. 12 The quadriceps muscle may con- tract concentrically (as the muscle shortens) or eccentrically (as the muscle lengthens). Markedly higher forces can be generated during an eccentric contraction, which is when most quadriceps muscle and tendon injuries occur. 13 Healing Potential of Tendons Tendons have excellent healing potential when the torn ends are reasonably approximated. Tendon healing begins with an inflammato- ry phase characterized by fibroblast migration. Granulation tissue then proliferates around the injury site, resulting in randomly oriented col- lagen fibrils. The density of the fibroblasts increases with time, pro- ducing more collagen. Optimal ten- don healing depends on surgical apposition and mechanical stabi- lization of the tendon ends. Once a tendon has been repaired, the su- ture material holds the tendon ends together, allowing fibroblasts to produce sufficient amounts of colla- gen to form a tendon callus. The strength of the repaired tendon depends on the orientation of the collagen fibrils and the overall colla- gen concentration. Over 3 to 6 months, the collagen remodels into an organized, longitudinal structure that resembles normal tendon. 14 In contrast with approximated tears, neglected ruptures with retraction of the proximal portion of the ten- don heal with scar tissue, resulting in a lengthened, weakened musculo- tendinous unit. Poor muscle func- tion will result without restoration of normal tendon length. 15 Studies of tendon healing have indicated that early controlled motion and tensile stress applied to a repaired tendon promote earlier organization and remodeling of collagen fibers, decreased scar tissue, and increased strength compared with tendon immobilization. 14 Etiology and Mechanism of Injury The normal, healthy quadriceps ten- don is a remarkably strong structure that is extremely resistant to tearing and can bear high loads without rupture. 16 Even when the extensor mechanism is under loads sufficient to disrupt it, it usually fails at a loca- tion other than the quadriceps ten- don. 1 In an early study, McMaster 16 determined the tensile strength and points of rupture of the quadriceps tendon in adult rabbits. Values also were determined for tendons that had been crushed or partially sev- ered or that had been ligated in an effort to obstruct the blood supply and produce aseptic necrosis. Ap- proximately 50% of a tendon’s fibers had to be severed for rupture to occur, even when subjected to extremely high forces. (Under nor- mal physiologic stresses, approxi- mately 75% of the tendon’s fibers must be cut before rupture occurs.) Rupture was possible under lesser loads at the osteotendinous and musculotendinous junctions or through muscle substance. 1,16 These data suggest that rupture of the Quadriceps Tendon Rupture Journal of the American Academy of Orthopaedic Surgeons 194 quadriceps tendon requires a weak- ened tendon. The tendons subject- ed to vascular insult also ruptured at lesser loads, suggesting that vas- cular disturbance may play a role in tendon rupture. 16 Degenerative changes, such as fatty and cystic degeneration, myx- oid degeneration, microangioblastic dysplasia, decreased collagen, and calcification, occur within tendons with age. All of these changes alter the tendon architecture 1,5,17,18 and may weaken it. However, quadri- ceps tendon rupture is rare even in older populations. Thus, other fac- tors may make the tendon suscepti- ble to rupture. In fact, approximate- ly one third of patients presenting with bilateral spontaneous rupture and 20% of those with unilateral rupture have a systemic medical condition that may accelerate degen- eration of the healthy tendon. 2,19 An array of pathologic conditions can affect the quadriceps tendon and contribute to its subsequent rupture by accelerating fatty degeneration or tendon infiltration or by decreasing collagen content. Renal disease and uremia can weaken the quadriceps mechanism by causing muscle fiber atrophy. Patients with chronic renal failure may develop changes within the collagen structure itself. 20 Dia- betes has been shown to precipitate vascular changes within the ten- don. 21 Rheumatoid arthritis causes chronic inflammatory changes re- sulting in synovitis and diffuse fibrosis. 22 Gout can lead to topha- ceous synovitis and fibrinoid necro- sis of the tendon. 23 Obesity causes fatty degenerative changes in the tendon. 7 Hyperparathyroidism, sys- temic lupus erythematosus, osteo- malacia, and use of steroids can cause microscopic damage to the vascular supply, altering the normal architecture of the tendon and thus increasing the susceptibility to com- plete rupture. 22,24-26 These findings suggest that it is necessary to search for an underlying medical condition in any patient presenting with bilat- eral spontaneous rupture of the quadriceps tendon. Most traumatic ruptures of the quadriceps tendon occur during attempts to regain balance to avoid a fall. The quadriceps muscle rapidly contracts against the individual’s body weight (eccentric contraction) while the knee is in a semiflexed position, placing the quadriceps tendon under its greatest tensile stress. 5,16 Although rare, direct trau- ma or a penetrating injury can result in disruption of the quadriceps ten- don. Clinical Presentation The diagnosis of quadriceps tendon rupture is largely based on a careful history and physical examination. There is usually the diagnostic triad of pain, inability to actively extend the knee, and a suprapatellar gap. 7-9 The pain is often described as an immediate, intense tearing sensation at the time of rupture. Immobili- zation of the extremity in extension results in pain relief. On examina- tion, the patient is unable to actively extend the knee and maintain exten- sion against gravity. Knee aspiration with an intra-articular anesthetic injection can help relieve the pain and allow the physician to more accurately assess the extensor mech- anism. Active knee flexion typically remains intact. A suprapatellar gap, a palpable depression just superior to the patella, is pathognomonic for quadriceps tendon rupture. Despite these relatively apparent signs and symptoms, the diagnosis of quadriceps tendon rupture may sometimes initially be missed. Diag- nosis may be more difficult when the injury is accompanied by a hemar- throsis, which can mask the presence of a suprapatellar gap. As a result, diagnostic failure rates of 10% to 50% have been reported, with delays in diagnosis ranging from days to months. 2,6,8,9 When the suprapatellar gap is not readily apparent because of local fluid accumulation, the sign may be elicited by having the patient actively flex the hip while in the supine position. This maneuver causes active shortening of the rectus femoris muscle, which draws the remaining portions of the quadriceps superiorly, thus widening the defect at the site of rupture. 8 Clinical evalu- ation also can be complicated by the presence of an intact patellar retinac- ulum so that the patient retains some ability to actively extend the leg despite complete rupture of the quadriceps tendon. However, with an intact retinaculum, the patient has weak knee extension and consider- able extensor lag. Comparison with the opposite leg is essential to deter- mine whether there is a ruptured quadriceps tendon with an intact retinaculum. Although a patient with a complete rupture may be able to ambulate, the examining physi- cian should maintain a high level of suspicion for this injury in anyone presenting with acute onset of pain and inability to actively extend the knee in the presence of a fully func- tional flexor mechanism. Imaging Several kinds of imaging studies can be useful for evaluation, includ- ing radiography, arthrography, ultrasound, and MRI. Anteropos- terior and lateral radiographs should be done initially because they usually reveal several consis- tent findings. In one study in 18 patients, 9 radiographs demonstrat- ed obliteration of the quadriceps tendon shadow in all 18 knees; a suprapatellar mass in 12; supra- patellar calcific densities in 12; and an inferiorly displaced patella in 10. Seventeen of 18 knees showed at least three of the previously men- tioned radiographic abnormalities. The suprapatellar mass represents Doron I. Ilan, MD, et al Vol 11, No 3, May/June 2003 195 retraction of the ruptured tendon, and the calcific densities may repre- sent either avulsed fragments of bone or dystrophic calcifications of the tendon itself. 9,27 Before the advent of MRI, ar- thrography was used to confirm the diagnosis of quadriceps tendon rup- ture. Extravasation of radiopaque material occurred at the site of the ruptured tendon in patients with quadriceps tendon rupture. How- ever, arthrography has been sup- planted by ultrasound and MRI, both of which are less invasive. 27 Ultrasound is a highly sensitive and specific means of assessment that delineates the location of the rupture and helps differentiate par- tial from complete tears. With com- plete ruptures, free ends of tendon fibers are separated by a hypoechoic to anechoic area representing hema- toma. Distraction of the patella increases the gap in complete tears but not in partial tears (Fig. 1). Ul- trasound also can be used to assess the repaired tendon after surgery. 27,28 However, its reliability is operator dependent. MRI (Fig. 2) is the most effective means to visualize the injured quad- riceps tendon, particularly when extensive hematoma and edema obscure the effectiveness of other studies. 27 MRI consistently and accurately depicts the injury and its location, making it a useful aid in surgical planning. 29,30 Additionally, visualization of other pathology within the knee is possible. How- ever, because of its cost, MRI should be reserved for cases in which other diagnostic methods have failed. 27,29,30 Management Incomplete Rupture Incomplete tears are usually managed nonsurgically, and treat- ment should commence immediately once a complete tear is ruled out. The patient is initially immobilized with the knee in full extension for 6 weeks, after which protected range- of-motion and strengthening exer- cises may be started. The immobi- lizer is progressively discontinued when the patient achieves good quadriceps muscle control and is able to straight-leg raise without discomfort. Traumatic hemarthrosis resulting in knee effusion is common after quadriceps tendon rupture. Jensen and Graf 31 showed that even small amounts of effusion decrease quad- riceps strength, thus supporting the need for aggressive treatment of knee effusion to promote rehabilita- tion. Ice, compression, and anti- inflammatory medication can be used, as well as knee aspiration to evacuate the hemarthrosis. Al- though no study has specifically examined the benefit of knee aspira- tion in quadriceps tendon injuries, hematoma aspiration may be of use in reducing pain and promoting recovery. To avoid difficulty once the hematoma has consolidated, aspiration should be done early. Acute Unilateral Rupture Nonsurgical management of complete quadriceps tendon rup- ture yields poor results, including long-term disability and weak- Quadriceps tendon Patella Figure 1 Sagittal ultrasound of a complete tear of the quadriceps tendon without (left) and with (right) manual distraction of the patella. Anechoic area (white arrows) repre- sents the rupture site and hematoma. Note the increased gap with distraction of the patel- la. This gap would not change in an incomplete tear. (Reproduced with permission from Bianchi S, Zwass A, Abdelwahab IF, Banderali A: Diagnosis of tears of the quadriceps ten- don of the knee: Value of sonography. AJR Am J Roentgenol 1994;162:1137-1140.) Figure 2 Sagittal T1-weighted MRI scan demonstrating complete rupture of the quadriceps tendon (arrow). Quadriceps Tendon Rupture Journal of the American Academy of Orthopaedic Surgeons 196 ness. 17,32 Delaying surgery often complicates the repair process and ultimately may lead to less satisfac- tory results. Without its distal ten- dinous insertion intact, the power- ful quadriceps apparatus begins to retract in the first few days after injury. Beyond 72 hours, retraction can make apposition of the torn ends difficult and can increase the tension along the suture lines. Al- though delayed repair does not always lead to poor results, early intervention is recommended. 2,3,33-35 In addition, there is no evidence that delaying repair (other than for necessary patient or soft-tissue fac- tors) is of any benefit. The need for surgical repair of a complete rupture to achieve optimal functional results is well accept- ed. 2,5,34 Many methods provide sat- isfactory results, and no single tech- nique clearly stands out as the most efficient and reliable means to return of function. 33 No random- ized, controlled studies have direct- ly compared techniques. Most pro- cedures are variations of the general techniques described below. Surgical Technique A straight midline or transverse incision is done to expose the exten- sor mechanism. Irrigation is used to remove the hematoma and to allow indentification and assessment of the tear. Full-thickness flaps are ele- vated medially and laterally to ac- cess the apex of retinacular tears. Absorbable sutures are placed in the medial and lateral retinacula but left untied until tendon repair is com- plete. The edges of the quadriceps tendon are débrided of grossly de- generative tissue and freshened for repair. Midsubstance ruptures can be treated with an end-to-end primary repair if sufficient tendon exists proximally and distally. Ruptures at or near the osteotendinous junc- tion, the most common site of in- jury, may be repaired through drill holes in the patella. Two heavy, nonabsorbable sutures are placed in a locked, running (Krakow or Bunnell) arrangement through the end of the tendon, leaving four loose strands free at the distal stump (Fig. 3). The superior pole of the patella is débrided and the anatomic insertion of the quad- riceps tendon is roughened to ob- tain a fresh cancellous bed that will allow tendon-to-bone healing. Three 2-mm drill holes are made parallel to each other and to the lon- gitudinal axis of the patella. Using a Keith needle or a Beath pin, the free ends of the sutures are passed through the holes and tied distally with the knee in full extension. Suture anchors have been used in place of drill holes with good re- sult. 36 The retinacular sutures are tied, although some surgeons prefer to leave the lateral retinaculum open to function as a release. The knee is taken through a 0° to 90° range of motion to ensure proper patellar tracking and to observe tension on the repair. Augmentation usually is not necessary 2,3,6,7,19 but may be done with wire, 37 Leeds-Keio liga- ment, 38 Dacron vascular graft, 39 or Mersilene tape 40 if the repair ap- pears to be tenuous. The Scuderi technique (Fig. 4), or quadriceps flap turndown, is another method to repair acute ruptures of the quadriceps tendon or augment tendon ruptures that appear to be tenuous after surgical repair. A partial-thickness triangular flap is fabricated from the anterior surface of the proximal tendon that is 2 inch- es along the base and 3 inches along each side. The flap is then folded distally over the rupture and su- tured in place. 5 Rehabilitation After repair, the knee is placed into a knee immobilizer for 48 hours, after which the wound is checked and the drains are discon- tinued. The knee is then placed into a locked, hinged brace, and the pa- tient is allowed complete weight bearing with the knee locked in full extension. Some authors 2,38,39 have advocated early range of motion; however, no difference was found between early range of motion and immobilization in one study of 53 ruptures. 33 With the knee brace in place, range-of-motion exercises and physical therapy are started after 4 to 6 weeks of immobiliza- tion. 6,7,19,34,41 The brace is removed after 12 weeks or when the patient has good quadriceps muscle control and can straight-leg raise. Good range of motion should be achieved by 12 to 16 weeks after repair. Figure 3 Technique for quadriceps tendon repair via drill holes in the patella. Sutures (dotted lines) are passed through three par- allel drill holes and tied distally. The cen- tral two suture strands are passed through the same hole and tied to the correspond- ing medial or lateral strand. (Adapted with permission from Azar FM, Pickering RM: Traumatic disorders, in Canale ST [ed]: Campbell’s Operative Orthopaedics, ed 9. St Louis, MO: Mosby, 1998, vol 2, p 1430.) Doron I. Ilan, MD, et al Vol 11, No 3, May/June 2003 197 Bilateral Tendon Rupture Bilateral simultaneous rupture of the quadriceps tendon is an uncommon injury pattern. Patients with such injuries often have chronic diseases and may first be evaluated by a physician other than an orthopaedic surgeon. These ruptures are frequently mis- diagnosed as neurologic paralysis or an arthritic condition. Pre- liminary workup is recommended to rule out predisposing factors such as gout, diabetes, or use of steroids. 6,7,19,30,41 Bilateral ruptures should be surgically treated in a manner similar to unilateral rup- tures. Rehabilitation regimens may have to be adjusted to individual needs. Yilmaz et al 42 reported a pa- tient who was not diagnosed with bilateral rupture until 5 months after injury and who was treated surgically with the Scuderi method. The patient underwent immediate physiotherapy with range-of- motion exercises. Full range of motion and strong extensor func- tion were reported at 5-year follow- up. Chronic Tendon Rupture and Repair Neglected or chronic rupture of the quadriceps tendon presents a dif- ficult problem in terms of reconstruc- tion. Reported results of surgical management are generally less satis- factory than those after treatment of acute tears. 5,33,40 When the tendon ends are able to be approximated, repair may be done as described. However, a large defect between the two ends of the tendon may occur, preventing tendon apposition. When the tendon has retracted enough to result in a large gap, the quadriceps muscle must be elevated from the femur and adhesions are released in an attempt to gain length. If apposition still is not pos- sible, a Codivilla lengthening proce- dure is recommended (Fig. 5). A full-thickness inverted V is devel- oped in the proximal segment of the quadriceps tendon. The lower mar- gins of the inverted V should end 1.3 to 2.0 cm proximal to the site of the rupture. The tendon ends are apposed and repaired with heavy nonabsorbable suture, and the trian- gular flap is turned down distally and sutured in place. The open up- per portion of the V is then sutured side to side. 5 Jumper’s Knee Tendinitis or tendinosis of the quadriceps or the patellar tendon is known as jumper’s knee, an overuse syndrome that results from repeti- tive overloading of the extensor mechanism. It is common in ath- letes who participate in running and jumping sports. Inflammation or degeneration occurs at the tendon insertion site, and patients typically complain of anterior knee pain and tenderness at the specific sites of in- flammation. The inferior pole of the patella is involved in 65% of these injuries, while the superior pole and the tibial tubercle are involved in 25% and 10%, respectively. 43 Blazina et al 10 developed a three- part classification system for jump- er’s knee. Phase I is characterized by pain after activity but no undue functional impairment. Phase II involves pain during and after activity while retaining the ability to perform at a satisfactory level. Phase III is characterized by pain during and after activity resulting in functional impairment that inter- feres with performance. Radio- graphic signs of jumper’s knee in- clude elongation or fragmentation of the pole of the patella, periosteal reaction of the anterior patellar sur- face (tooth sign), or calcification of the tendon. Patients who exhibit symptoms of phases I and II respond well to nonsurgical treatment, such as activity modification, rest, and anti- inflammatory medication. Jumping and eccentric exercises are discour- aged. Functional, pain-free physio- therapy is done after resolution of symptoms. Gradual return to ac- tivity is important to prevent recur- rence. Cortisone injections may increase risk of rupture and thus should not be used. Patients with Figure 4 Scuderi technique of quadriceps tendon repair. A, Quadriceps tendon tear exposed. B, Direct repair done with heavy nonabsorbable suture. Dotted lines represent inverted V cut (partial thickness) to be made. C, Partial-thickness triangular flap (arrow) reinforcing the repair. (Adapted with permission from Scuderi C: Ruptures of the quadri- ceps tendon: Study of twenty tendon ruptures. Am J Surg 1958;95:626-635.) A B C Quadriceps Tendon Rupture Journal of the American Academy of Orthopaedic Surgeons 198 phase III jumper’s knee are treated the same as those with phase I and II symptoms, but the rest period is prolonged. Chronic phase III cases may require surgical débridement. 17 Results In 1958, Scuderi 5 reported good to excellent results in 85% of patients (11/13) treated with his method of repair. Since then, several multi- patient, retrospective studies have evaluated the results of various methods of surgical repair and post- operative protocols. Siwek and Rao 3 evaluated 36 ruptures and found that all patients treated pri- marily had good or excellent results based on range of motion and strength, whereas three patients treated after a 2-week delay had good results and three treated at 4, 12, and 14 weeks after injury had unsatisfactory results. In another series, 4 83% of patients (15/18) had good or excellent results, but no cor- relation was made with the time from injury to repair. Patellofem- oral congruence was evaluated radio- graphically; 13 of 18 patients had incongruence compared with the contralateral knee. This did not cor- relate with range of motion or strength, but all patients with incon- gruence had residual pain. Rougraff et al 33 reviewed 53 rup- tures in which multiple surgical techniques and postoperative regi- mens were used; no differences were found based on repair tech- nique or postoperative protocol. However, patients with delayed surgery had poorer functional out- comes and decreased satisfaction scores. Using functional surveys and objective testing, Konrath et al 2 studied 51 quadriceps tendon rup- tures in 39 patients. They reported that 92% were satisfied and that 84% returned to their previous occupations. However, 51% were unable to return to the same pre- surgery level of recreational activity. There was a 12% strength loss in the quadriceps tendon and 14% in the hamstrings, as well as an 8° loss of range of motion. One patient expe- rienced re-rupture, and one had an extensor lag of 10°. However, there was no correlation between the length of time from tendon rupture to surgical repair and final strength, functional score, or activity score. 2 This suggests that, whether repair is done immediately or after a delay, surgical treatment can provide reli- able results. However, many others have indicated that a delay may adversely affect the results of ten- don repair. Patients with quadri- ceps tendon rupture older than 2 weeks may have muscle retraction of up to 5 cm, which may result in the need for quadriceps lengthen- ing, tendon or muscle transfer, or a combination during surgery. 44 Complications Loss of knee motion is one of the most common complications after quadriceps tendon repair. In partic- ular, patients have difficulty regain- ing full knee flexion. Another com- plication associated with repair of the quadriceps tendon is extensor weakness, in which the quadriceps muscle undergoes atrophy, leading to an extensor lag. Siwek and Rao 3 reported that 75% of their patients who underwent acute repair of rup- tured quadriceps tendons had per- sistent quadriceps atrophy of 2 to 4 cm. Despite the marked atrophy, strength was adequate for normal knee function. Such extensor lag usually can be corrected with ap- propriate rehabilitation. Other potential, though infre- quent, surgical complications in- clude wound infection and skin dehiscence, which are often related Figure 5 Codivilla method of quadriceps tendon lengthening and repair. A, Chronic quadriceps tendon tear exposed. Proximal retraction prevents direct apposition of the tear. Dotted lines represent inverted V cut (full thickness) to be made. B, The inverted V cut allows the tear to be approximated and repaired. C, The proximal aspect of the invert- ed V repaired side to side. A full- or partial-thickness flap may be used to augment the repair, as in the Scuderi technique (Fig. 4). (Adapted with permission from Scuderi C: Ruptures of the quadriceps tendon: Study of twenty tendon ruptures. Am J Surg 1958;95:626-635.) A B C Doron I. Ilan, MD, et al Vol 11, No 3, May/June 2003 199 to the subcutaneous positioning of wires and/or the large-caliber non- absorbable sutures used for surgical repair. Placement of the sutures directly in line with the incision should be avoided to prevent de- layed wound healing. 40 Use of a postoperative closed suc- tion drain is recommended to avoid hemarthrosis. Wire breakage may occur, necessitating removal because of skin irritation and wire extrusion. Patella alta or baja or patellar incon- gruity also can occur, which may lead to subsequent patellofemoral degen- eration. Therefore, close attention should be paid intraoperatively to patellar alignment when repairing the extensor mechanism. Re-rupture of the repaired tendon may occur, requiring revision surgery. 33 Summary Rupture of the quadriceps tendon is an infrequent, disabling injury that requires prompt diagnosis and surgical repair. This injury can be associated with underlying medical conditions and is usually seen in patients older than 40 years. Metabolic disease, obesity, and steroid use may alter the normal architecture of the quadriceps ten- don by causing microscopic dam- age to the vascular supply, thus increasing susceptibility to rupture. However, most traumatic ruptures of the quadriceps tendon are caused by an indirect, violent, eccentric muscle contraction; direct trauma rarely causes disruption. The hallmark of quadriceps tendon rupture on physical examination is acute onset of pain with an im- paired ability to extend the knee and a palpable suprapatellar gap. Plain radiographs, ultrasound, and MRI are used for diagnosis and evaluation. Nonsurgical management is the accepted course of treatment for incomplete quadriceps tendon rup- tures and jumper’s knee. Surgical repair is recommended to achieve optimal functional results in com- plete tendon ruptures. The most common surgical repair involves placing heavy, nonabsorbable su- tures through parallel transosseous tunnels in the patella. Chronic quadriceps tendon ruptures may require a lengthening procedure to address the marked retraction of the quadriceps tendon that commonly occurs. Timing of surgical repair for opti- mal outcome is unclear. Some stud- ies have shown excellent and good results with immediate repair and unsatisfactory results with delayed surgical repair, while others have shown no correlation between tim- ing of repair and surgical outcomes. Based on these conflicting data, quadriceps tendon ruptures should be treated in a timely manner, thus avoiding possible suboptimal out- comes that could be attributed to surgical delay. References 1. Conway FM: Rupture of the quadri- ceps tendon: With a report of three cases. Am J Surg 1940;50:3-16. 2. Konrath GA, Chen D, Lock T, et al: Outcomes following repair of quadri- ceps tendon ruptures. J Orthop Trauma 1998;12:273-279. 3. Siwek CW, Rao JP: Ruptures of the extensor mechanism of the knee joint. J Bone Joint Surg Am 1981;63:932-937. 4. 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