SINGLE-SURGEON EXPERIENCE WITH CUSTOM PATELLOFEMORAL REPLACEMENT

Introduction Patellofemoral replacement (PFR) is an accepted treatment for patients with endstage isolated patellofemoral arthritis. While off-the-shelf PFR implants are widely available, trochlear anatomy is highly variable, and consistently achieving good fit can prove challenging. A custom device derived from preoperative computed tomography (CT) imaging provides an exact fit every time without need for intramedullary rods, bone resection, or sculpting. This study aims to review a single-surgeon experience with custom PFR to assess outcomes, reoperations, and mid-term survival. Methods A private practice registry queried for patients who underwent PFR using custom trochlear implants from 2009 to 2023 by one surgeon revealed 46 patients with 60 involved knees. Fixation was cemented, using custom trochlea with standard polyethylene patellae. Results Mean patient age was 59.8 years (range, 32 to 94 years), mean BMI was 30.3 kg/m 2 (range, 17 to 51 kg/m 2 ), and 72% of knees were in women (43 knees, 33 patients). Diagnosis was 59 osteoarthritis and one post-traumatic. Mean follow-up was 7.0 years (range, 0 to 15.2 years). One early death occurred in a 71-year-old man at 31 days postoperative. All remaining patients had minimum 2-year follow-up. Range of motion was high both preoperatively (mean 121.9° ±11.7°) and postoperatively (mean 123.0° ±8.4°; p=0.551). Pain levels on visual analogue scale improved significantly from 7.3 ±2.8 to 2.2 ±3.0 (p<0.001). Three patients (5.0%) required manipulation. Two patients had arthroscopic debridement for synovitis. In total, nine patients (10 knees, 16.7%) required revision to total knee arthroplasty (TKA) at a mean 6.5 years (range, 2 to 11 years) postoperative, all for tibiofemoral arthritic progression, with one concomitant femoral loosening. All revisions used primary TKA implants without stem extensions or augments. Conclusion Custom PFR provides patients with endstage isolated patellofemoral arthritis a bone-conserving, minimally invasive treatment option with excellent durability, function, and pain relief.