The patellar tendon, as part of the extensor mechanism of the knee, is crucial to normal function of the lower extremity, especially during ambulation. Patellar tendon injuries, which most commonly occur in men in their thirties and forties, usually result from a weakened patellar tendon that is subjected to eccentric loading. Chronic patellar tendon rupture is associated with various risk factors, such as systemic lupus erythematosus, rheumatoid arthritis, diabetes mellitus, chronic kidney disease, and steroid use. Although patients with an acute patellar tendon rupture who undergo repair generally experience excellent outcomes, patients with a chronic patellar tendon injury are a challenge to treat because tissue often is poor and predominantly fibrous in nature. Although direct repair may be an option in these patients if tissue quality is adequate, reconstruction often is preferred.

This video provides an overview of chronic patellar tendon injuries and demonstrates patellar tendon reconstruction with the use of hamstring autograft and medial collateral ligament repair. The video provides an overview of the anatomy, biomechanics, pathogenesis, diagnosis, and management of chronic patellar tendon injuries followed by a discussion of the indications for repair and reconstruction. The video discusses the case presentation of a 53-year-old man with right knee pain 6 weeks after his knee buckled while descending stairs. A physical examination revealed tenderness to palpation over the anterior aspect of the right knee and an inability to actively extend the right knee. The right knee demonstrated increased opening to valgus stress at 0° and 30° degrees of knee flexion. Advanced imaging studies revealed a chronic rupture of the patellar tendon as well as anterior cruciate ligament and medial collateral ligament ruptures. The patient underwent patellar tendon reconstruction with the use of a hamstring autograft and medial collateral ligament repair, with a plan for staged anterior cruciate ligament reconstruction. The patient was advanced through a standardized rehabilitation protocol and experienced gradual relief of his symptoms, decreased extensor lag, and increased stability to valgus stress. Patellar tendon rupture can be managed via surgical repair or reconstruction. Reconstruction often is preferred in patients with a chronic patellar tendon rupture because these injuries are associated with poor tendon quality. Although studies have demonstrated good outcomes in patients with a chronic patellar tendon rupture who undergo reconstruction with the use of a hamstring autograft, results are contingent on careful and consistent technique.