Clinical and radiological results after one hundred fifteen MPFL reconstructions with or without tibial tubercle transfer in patients with recurrent patellar dislocation—a mean follow-up of 5.4 years

Abstract

Medial patellofemoral ligament reconstruction (MPFLR) shows low recurrent rates and high satisfaction. Reports on outcome at mid-term follow-up in a large cohort with or without tibial tubercle transfer (TTT) are scarce. One hundred six patients (115 knees; 24.3 ± 8.7years) with recurrent patellar dislocation underwent MPFLR with ipsilateral gracilis autograft and were included in this retrospective follow-up study. In 43 knees, simultaneous TTT was performed for patellar maltracking due to patella alta or increased tibial tubercle trochlear groove distance (TT-TG). Kujala and subjective knee scores were recorded pre- and post-operatively. Eighty-seven percent of the patients were satisfied at a mean follow-up of 5.4 ± 3.1years. The Kujala score increased in 81.7% of all knees from 50.9 to 76.2 points (p < 0.01). Patients with a decreased Kujala score were not different in terms of follow-up time, age, trochlear dysplasia, or post-operative patellar height. The decline was related to an increase in pain, whereas functional scores remained identical. There were six patients with persisting instability, three with patellar re-dislocation. Re-operation was necessary in 24 patients (21.2%), mainly for implant removal after TTT and loss of flexion. Performing TTT had no significant influence on the subjective outcome. Patients with more than eightyears of follow-up (n = 27) did not show any difference in the subjective outcome parameters, or in osteoarthritis progression. MPFLR with and without TTT is a reliable treatment option for recurrent patellar dislocation without deterioration at mid-term follow-up. Persisting pain is a major post-operative issue that seems to be unrelated to patellofemoral anatomy.