Background: Symptomatic patellofemoral osteoarthritis is a challenge to the orthopaedic surgeon. In comparison to Total Knee Arthroplasty (TKA), little has been written about unicompartmental patellofemoral arthroplasty. Although, recent reports have shown more promise, the procedure has not gained wide acceptance.
Materials and Methods: We present the outcome of 23 unicompartmental patellofemoral arthroplasties on 19 patients performed in a district general hospital in the UK. The procedures were performed by a single surgeon (RSG), with a special interest in knee surgery. All the patients had failed a trial of non-operative treatment which included non-steroidal anti-inflammatory analgesia and physiotherapy. Some knees had undergone previous surgical procedures including arthroscopy (12), carbon fibre patch implantation (5), tibial tubercle transfer (1), lateral release (1), medial release (1) and excision of patellar bursa (1). Multiple arthroscopies had been performed on 4 knees.
The arthroplasty was performed via an anterior midline incision and medial parapatellar approach. All patients received Leicester Patellofemoral Prosthesis (Corin). One patient had a revision procedure following a failed PFJR performed elsewhere. The age of the patient at the time of operation ranged from 31–68 years (Mean age 50.3 years). The duration of follow-up was 6 months to 88 months (Mean 36 months). The results were evaluated using the Oxford Knee Score.
Results: One patellofemoral arthroplasty was converted to TKA after 41 months. There was no infection or loosening of the components in any patient. All patients reported relief of post-operative discomfort by 6 months except for one patient who developed hypersensitive skin lateral to the scar at 6 months. All patients said that their knees were significantly better after the procedure. Oxford Knee Scores ranged from 17 to 54 (Median 29). All except one patient reported that they would to undergo the procedure on their other knee (unilateral cases) and would recommend the procedure to friends/family.
Conclusion: The early and medium term results of uni-compartmental patellofemoral arthroplasty in our study are encouraging with patients reporting significant improvement in knee symptoms. We feel that careful patient selection and meticulous attention to surgical detail contribute to better outcomes.
