Prevalence of osteoarthritis and clinical results after the Elmslie-Trillat procedure: a retrospective long-term follow-up

Tibial tuberosity medialisation may be followed by osteoarthritis in the long term due to increased patellofemoral contact pressure and altered knee joint kinematics. We aimed to (1) systematically assess the grades of tibiofemoral and patellofemoral osteoarthritis ten to 30 years after the Elmslie-Trillat procedure and (2) to evaluate long-term knee function and activities of daily living. A total of 26 patients (30 knees) were re-evaluated at a minimum follow-up of 12.3 years (mean 20.9 +/- 4.1 years). Osteoarthritis was graded according to Kellgren and Lawrence (K/L) and Sperner. All patients were clinically evaluated using the Knee Society Score (KSS) and Knee injury and Osteoarthritis Outcome Score (KOOS). Radiographic data were compared to an age-, sex- and body mass index-matched control group of healthy patients. Radiographic evaluation revealed seven cases (23.3 %) with advanced osteoarthritis (K/L and Sperner grades 3 and 4). However, the observed differences from the matched cohort were not statistically significant (P = 0.189). A positive correlation was found between the age at index procedure and tibiofemoral osteoarthritis at follow-up (P = 0.013). Patient satisfaction was relatively high, showing a mean KSS of 89.9 (knee score) and 94.8 (function score), and a mean KOOS of 78.7. However, we noted four cases of frequent patellar re-dislocations and three total knee arthroplasties. The Elmslie-Trillat procedure was associated with several cases of advanced tibiofemoral and patellofemoral osteoarthritis in the long term, especially if the procedure was performed late. Clinical results were still good to excellent in the majority of patients despite some observed cases of re-dislocations and decreased ability to perform sports.