Medial patellofemoral ligament reconstruction as an isolated or combined procedure for recurrent patellar instability

The principal aim of this study was to report the outcomes of medial patellofemoral ligament (MPFL) reconstruction, used as either an isolated procedure or in combination with another stabilization procedure, for the primary treatment of recurrent patellar instability. Between 2007 and 2012, 45 patients with recurrent patellar instability and no prior stabilization surgery had an MPFL reconstruction by a single surgeon, either as an isolated procedure or in combination with another stabilization procedure. Questionnaires detailing patellar instability since surgery, knee pain, ability to negotiate stairs, and sports participation were completed, and data regarding examination and radiological findings were collected from the medical record. A total of 36 (80 %) patients completed the questionnaire at a mean of 3.1 years (minimum 1 year), whilst a further 11 % had clinical follow-up of greater than 1 year. Four patients were excluded due to lack of adequate follow-up. Thirty-one patients had an isolated MPFL reconstruction and none had further patellar instability. Of the ten patients who had a combined procedure, one experienced recurrent instability. Return to sport rates were 81 and 57 % for the isolated and combined groups, respectively, with the majority returning to strenuous sport (81 and 57 %, respectively). Most patients (96 and 80 %) could negotiate stairs without difficulty, whilst 38 and 40 % reported some degree of anterior knee pain. This study shows that satisfactory results can be obtained using MPFL reconstruction either in isolation or in combination to treat recurrent patellar instability. Whether the indications for an isolated MPFL can be extended further remains unclear.