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Repair of Quadriceps and Patellar Tendon Tears
Michael Danaher1, Scott C Faucett2, Nathan K Endres1
1Department of Orthopaedics and Rehabilitation, Larner College of Medicine, University of Vermont, Burlington, Vermont, U.S.A.
Abstract:
Tears of the quadriceps or patellar tendon usually occur after a sudden eabccentric contraction and are diagnosed by a palpable gap at the injury site combined with an inability to perform a straight leg raise. Bilateral knee radiographs may demonstrate patella alta with patellar tendon tears and patella baja with quadriceps tendon tears compared with the uninjured knee. Ultrasound and magnetic resonance imaging can be helpful when there is uncertainty in the diagnosis. Surgical treatment is indicated for complete tears and some high-grade, partial tears. Nonabsorbable high-strength sutures or suture tape are placed in running locking fashion along the injured tendon and secured to the patella with bone tunnels (i.e., transosseous) or suture anchors. The transosseous technique requires exposure of the length of the patella to drill 3 bone tunnels to shuttle the sutures and tie over either pole of the patella. The suture anchor technique allows for a smaller incision and less soft-tissue dissection and may use a knotted or knotless technique. Biomechanical testing with load to failure is not statistically different between the transosseous and anchor techniques, although anchors have been shown to have less gap formation at the repair site. Repair augmentation with a graft may be beneficial in mid-substance injuries, chronic tears, and in cases of compromised tissue quality. Rehabilitation usually can be initiated immediately with protected weight-bearing in an orthosis, safe-zone knee passive range of motion, and avoidance of active extension. After a period of 6 weeks, rehabilitation can progress with full range of motion and a concentric strengthening program.
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