The long-term results of tibial tubercle transfer for patellar instability

Abstract

The authors report results of a series of 57 tibial tubercle transfers in 46 patients between 1974 and 1984. Of 95 patients operated on for objective and potential patellar instability, 57 (67%) were reviewed with an average follow-up of 14.9 years. At follow-up 19.3% were free of pain. There were no recurrent patellar subluxations and 49.2% of patients were satisfied with the operation as regards episodes of instability. Early medial tibio-femoral arthritis was found in 5 cases. In two there was complete loss of the joint line and in one case complete loss of the medial patellofemoral joint line. Follow-up did not allow us to make an assessment of the adverse role of the tibial tubercle transfer on the patello-femoral and medial tibio-femoral compartment. We consider that the secondary effects are due to a failure to respect the contraindications, which for us were genu varum, previous medial meniscectomy and transfer with a normal tuberosity/trochlea offset rather than due to the transfer itself. The authors believe that tibial tubercle transfer is still indicated in the treatment of objective and potential patellar instability if the symptomatology is dominated by instability and dislocation of the patella and if the tuberosity/trochlea offset is greater than 20 mm.