Purpose: The goal of the fixation of painful osteochondritis dissecans of the femoral condyles in adults is to integrate the osteochondral fragment and thus achieve a normal hyaline cartilaginous coverage. The addition of a biological process to primary fixation may result in improved fragment integration (hybrid fixation). Osteochondral plugs may fulfil this role. The aim of this study was to evaluate long-term clinical and radiological results after hybrid fixation of unstable osteochondritis dissecans. The hypothesis was that the rate of secondary osteoarthritis would be low.
Methods: Nine patients treated by hybrid fixation were retrospectively reviewed at a median follow-up of 10.1 years (range 7-14). The median age at surgery was 21 (range 17-28). Six of them were evaluated as ICRS grade II and three, as ICRS grade III. The mean surface of the lesion was 4.5 cm2. All patients were followed up clinically (IKDC, KOOS, Lysholm) and radiologically [Kellgren-Lawrence score (KL)].
Results: During arthroscopic assessment at the time of screw removal (3 months after surgery), the fragments were stable, and autograft plugs were all well integrated. At the most recent follow-up visit, the median IKDC score was 85.8 (range 51.72-100), the KOOS score was 87.7 (52.4-100), and the Lysholm scale score was 89.8 (77-100). In 7 out of 9 patients, radiographs showed a joint space KL grade of 0 or 1.
Conclusion: Hybrid fixation for treating osteochondritis dissecans lesions of the femoral condyles using mechanical and biological fixation provides healing of the osteochondral fragments with good long-term outcomes. No significant osteoarthritic change was seen with this technique at a mid-term follow-up.
Level of evidence: IV-case series.
Keywords: Adult osteochondritis dissecans; Biological fixation; Knee; Mosaicplasty; Osteochondral graft.