Low Incidence of Osteoarthritis and Excellent Clinical Outcomes at Minimum 10 Years Following Primary Repair of the Anterior Cruciate Ligament

Background: Anterior cruciate ligament (ACL) primary repair (ACLPR) has been proposed as a treatment option for select patients with proximal ACL tears. However, long-term data are imperative to validate the utility of this technique. Purpose: To determine the long-term incidence of posttraumatic osteoarthritis (PTOA) and clinical outcomes after arthroscopic ACLPR. Study Design: Case series; Level of evidence, 4. Methods: Prospective data were collected on consecutive patients with modified Sherman type 1 ACL tears who underwent ACLPR between 2008 and 2013. Inclusion required minimum 10-year follow-up. Standardized radiographs of both knees were obtained preoperatively and at 10-year follow-up to assess PTOA as determined by Kellgren-Lawrence (KL) grade and minimal joint space width. Clinical outcomes included repair failure (anterior tibial translation side-to-side difference (ATT SSD) ≥3 mm, grade ≥2 Lachman, grade ≥2 pivot-shift test and/or subjective instability) and reoperation rates, ATT SSD, International Knee Documentation Committee (IKDC) Subjective Knee Form, Lysholm, Forgotten Joint Score–12 (FJS-12), ACL Return to Sport after Injury Survey (ACL-RSI), Tegner activity scale (Tegner), and Patient Acceptable Symptom State (PASS). Results: Outcomes were available for 16 of 18 eligible patients (median age at surgery, 40 years; 79% male) with a median follow-up of 11 years (IQR, 10-12 years). PTOA assessment revealed 42% (5/12) KL grade 0, 50% (6/12) grade 1, and 8% (1/12) grade ≥2. There were no significant differences in KL grading compared with preoperative ipsilateral values ( P = .69) and contralateral values at 10 years ( P = .72). Joint space width in all compartments showed no significant change (all P > .05). Repair failure and reoperation occurred in 12.5% (2/16) of patients each. ATT SSD was 0.9 ± 1.4 mm. Median patient-reported outcome measures were as follows: IKDC, 95 (93-99); Lysholm, 96 (90-100); FJS-12, 96 (90-100); ACL-RSI, 90 (68-100); equal preinjury to postoperative Tegner ( P = .25); and PASS was achieved in 92% to 100%. Conclusion: At minimum 10-year follow-up, a low incidence of clinically relevant radiographic osteoarthritis was observed in patients who underwent ACLPR. These patients can expect to experience a high rate of clinically significant outcome achievement, preserved knee stability, and an acceptable repair failure rate of 12.5% at long-term follow-up. While the present study provides meaningful insights, validation in larger cohorts remains essential.