Isolated anterior cruciate ligament reconstruction in patients aged fifty years: comparison of hamstring graft versus bone-patellar tendon-bone graft

Anterior cruciate ligament (ACL) deficiency contributes to symptomatic functional instability of the knee, regardless of age. We evaluated patient-reported clinical outcome, instrumental stability and prevalence of radiological osteoarthritis based on two homogenous patient samples aged 50 years, an average of three years after isolated ACL reconstruction. ACL reconstruction using a bone-patellar tendon-bone (BPTB) autograft was done in 19 patients and a four-stranded semitendinosus tendon (ST) autograft in 22 patients. Clinical and functional follow-up assessment was performed an average of 32 months after surgical treatment. Clinical and functional follow-up assessment included the International Knee Documentation Committee (IKDC) score, Tegner score and Lysholm score. Instrumental stability testing was carried out using the KT-1000 (TM) arthrometer. The degree of degenerative changes and prevalence of osteoarthritis was based on the Kellgren-Lawrence classification. Mean follow-up was 32 months (range, 28-36). Mean age was 49.4 years in both groups. The median pre-injury Tegner score was 5.5 (range, 2-8) and the median preoperative Lysholm score was 35 (range, 15-69). At two years, all variables improved significantly for both groups compared to the preoperative values (P < 0.05), with no significant intergroup differences. Approximately 76 % of patients were graded A or B according to the IKDC score in both groups. Activity level according to the scores of Tegner and Lysholm was 4.9/5.3 and 83.4/82.5 on two-year-follow up in both groups. Radiological assessment reported degenerative changes of grade I Osteoarthritis (OA) in 36 % of patients. Grade-II OA was found in 31 % of patients. Grade-III OA and grade-IV OA were found in about 24 % and 7 % of all patients, respectively. Correlation analyses showed significant relationships between conservation of knee-joint stability and clinical outcome according to the IKDC score, and activity level according to the Lysholm score (p < 0.05). Arthroscopic ACL reconstruction using either BPTB graft or hamstring graft in appropriately selected middle-aged patients results in patient satisfaction and good clinical results, with return to a reasonable level of activity regardless of surgical method and graft choice.