An assortment of clinical trials have been done presenting the effectiveness of autologous matrix-induced chondrogenesis (AMIC) for the regeneration of chondral leasions. The purpose of the study was to underline the accessability of the acetabulum and the femoral head through the known portals and prove i) the feasibility of placing the AMIC in the different zones of the hip joint and ii) check for dislocation after joint movement. Six human cadavers underwent hip arthroscopy on both hips. Two chondral lesions were set on each femoral head and two in the acetabulum to evaluate a total of 48 defects. After microfracturing an autologous matrix-induced chondrogenesis graft was placed on these lesions arthroscopically. After repeated joint movement the dislocation of the graft was checked. It was possible to place the AMIC graft in all 48 chondral lesions. The time needed for placing the graft was 8±2.9 minutes. A trend of time reduction could be detected throughout this study as the surgeon gained more experience. For the femoral head, after twenty cycles of joint movement 18/24 spots showed no displacement, 4/24 showed minor displacement (<3 mm) and 2/24 showed major displacement (>3 mm). None showed total displacement. For the acetabulum 22/24 spots showed no displacement and 2/24 showed minor displacement. A combined microfracturing and placing of an AMIC graft of focal chondral lesions of the hip joint can be done arthroscopically. Prospective randomized in vivo studies should compare the results of arthroscopilally placed AMIC grafts with microfracturing and microfracturing alone.
Keywords: autologous matrix-induced chondrogenesis; chondral leasion; hip; hip arthroscopy.