Combined lateral retinacular release with drilling chondroplasty for treatment of patellofemoral osteoarthritis associated with patellar malalignment in elderly patients.

This paper described a less invasive surgical technique that was performed for treatment of elderly patients with isolated patellofemoral (PF) osteoarthritis (OA) associated with patellar malalignment, although their tibiofemoral joints are minimally osteoarthritic. Two hundred and thirty-four knees in 126 consecutive elderly patients (average, 72 yrs) diagnosed with combined disorders were treated by lateral retinacular release with drilling chondroplasty. The inclusion criteria were patient age ≥ 65 yrs, isolated stage 2 or 3 PF-OA (modified Iwano staging by radiology), and a laterally subluxed patella shown on a Merchant's axial radiograph. Outcome was judged by three parameters: clinical PF function (modified Kujala scoring), congruence angle, and PF-OA staging. Two hundred and one knees in 107 patients were followed-up for an average of 4.2 yrs (range, 2.1-7.5 yrs) and 19 patients were lost to follow-up. No surgical complications occurred through the course of treatment. Clinical PF function improved in knees that showed unsatisfactory performance (modified Kujala scoring < 32) preoperatively, with 78.1% of the knees showing satisfactory performance (modified Kujala scoring ≥ 32) at the latest follow-up. Congruence angle improved in 85.6% of the knees and PF-OA staging improved in 77.1% of the knees. Combined lateral retinacular release with drilling chondroplasty is a feasible alternative for treatment of PF-OA associated with patellar malalignment in elderly patients where knee arthroplasty cannot be performed by various reasons. Advantages of this combined surgical technique include a less invasive procedure, minimal complication rate, and an acceptable success rate (78%, modified Kujala scoring≥32).