Clinical evaluation of a resurfacing device implant for femoral osteochondral defects greater than 1 cm2 with a minimal follow-up of 4 years: a prospective cohort study.

PURPOSE: Osteochondral defects have a limited capacity to heal and can evolve to an early osteoarthritis. A surgical possibility is the replacement of the affected cartilaginous area with a resurfacing device BioPoly™ RS Partial Resurfacing Knee Implant. The aim of this study was to report the clinical and survival outcomes of the BioPoly™ after a minimum follow-up of 4 years. METHODS: This study included all patients who had a BioPoly™ for femoral osteochondral defects greater than 1 cm2 and at least ICRS grade 2. The main outcome was to observe the KOOS and the Tegner activity score were used to assess outcomes preoperatively and at the last follow-up. The secondary outcomes were the VAS for pain, the complications rate post-surgery and survival rate of BioPoly™ at the last FU. RESULTS: Eighteen patients with 44.4% (8/18) of women were included with a mean age of 46.6 years (11.4), a mean body mass index (BMI) of 21.5 (kg/m2) (2.3). The mean follow-up was 6.3 years (1.3). We found a significant difference comparing pre-operative KOOS score and at last follow-up [respectively, 66.56(14.37) vs 84.17(7.656), p < 0.01]. At last follow-up, the Tegner score was different [respectively, 3.05(1.3) vs 3.6(1.3), p < 0.01]. At 5 years, the survival rate was of 94.7%. CONCLUSIONS: BioPoly™ is a real alternative for femoral osteochondral defects greater than 1 cm2 and at least ICRS grade 2. It will be interesting to compare this implant to mosaicplasty technic and/or microfracture at 5 years postoperatively regarding clinical outcomes and survival rate. LEVEL OF EVIDENCE: Therapeutic level III. Prospective cohort study.