ROTATIONAL ACETABULAR OSTEOTOMIES - A RABBIT MODEL

We investigated the morphological changes in the articular cartilage a fter rotational acetabular osteotomy in 16 adolescent rabbits. Radiolo gical and histological studies were conducted at 12 and 24 weeks posto peratively. The radiological evaluations at 12 and 24 weeks showed sig nificantly increased femoral head coverage. No cases of osteonecrosis of the acetabulum or femoral head nor narrowing of the joint space was observed. The histology of the articular cartilage at 12 weeks postop eratively showed cloning and hypercellularity of the chondrocytes in t he medial portion of the acetabular roof, indicating remodelling due t o the increased weight-bearing stress caused by the osteotomy. The his tology at 24 weeks postoperatively showed less cloning of the chondroc ytes, indicating that the remodelling process in the articular cartila ge induced by this procedure was almost complete at 24 weeks. Degenera tion of the articular cartilage was not observed within 24 weeks of th e operation.