Long-term outcome of endoscopic anterior cruciate ligament reconstruction with patellar tendon autograft: minimum 13-year review

BACKGROUND: Short-term results of anterior cruciate ligament reconstruction are well reported; however, there are no studies evaluating endoscopic reconstruction of the anterior cruciate ligament with a minimum 10-year follow-up. HYPOTHESIS: Anterior cruciate ligament reconstruction with patellar tendon graft affords good subjective results and clinical laxity assessments but may be associated with development of osteoarthritis over the long term. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Endoscopic anterior cruciate ligament reconstruction was performed in 67 consecutive patients without significant articular surface damage. Patients were assessed at 5, 7, and 13 years after surgery with the International Knee Documentation Committee Knee Ligament Evaluation Form, Lysholm knee score, hop tests, kneeling pain, and radiographs. RESULTS: At 13-year review, self-reported assessments remained excellent; 96% of patients reported normal or nearly normal knee function. Grade 0 or 1 results were seen in more than 92% of patients on laxity testing. Patients who had undergone meniscectomy at the time of reconstruction had increased laxity between 7 and 13 years on instrumented testing (P = .03) and 6 times greater odds of anterior cruciate ligament graft rupture than if they had not undergone meniscectomy (95% confidence interval, 1-37). Degenerative changes on radiographs were found in 79% of patients at 13 years and were associated with meniscectomy (P = .006), loss of extension (P = .05), and greater laxity on Lachman test (P = .04). CONCLUSIONS: Endoscopic anterior cruciate ligament reconstruction with patellar tendon autograft affords and maintains good self-reported assessments and clinical ligament evaluation up to 13 years. Radiographic degenerative changes were seen in three quarters of patients. Almost half developed loss of extension, suggesting onset of early osteoarthritis. Patients who had undergone meniscectomy at the time of reconstruction had increased clinical ligament laxity over time and greater odds of graft rupture, possibly reflecting the effect of prolonged increased strain on the graft. Continued follow-up is required to resolve concerns regarding integrity of the patellar tendon graft beyond 13 years, particularly in the absence of meniscal tissue.