Healing and remodeling of articular cartilage after reconstruction of acetabular posterior wall

Abstract

Objective To evaluate the efficacy of small cylindrical cartilage autografts in repairing articular cartilage defects of the reconstructed posterior wall on the basis of analysis of the pathological characteristics of the articular surface. MethodsIn this experiment, 12 canis familiaris had a survival surgery to make animal models of posterior acetabular defects which were reconstructed with iliac crest autografts. The 24 hips were divided into 3 groups randomly. In group A, the small cylindrical cartilage autografts were seeded into the cartilage defects to anatomically reconstruct the posterior wall. In group B, the cartilage defects were anatomically reconstructed. In group C (control group), the cartilage defects were conventionally reconstructed. The animals were sacrificed to harvest the hips after 12 weeks. The new tissues were assessed according to Pineda criteria and a histological comparison was made between the 3 groups.Results The repaired cartilages in group A belonged to hyaline-cartilage-like repair with characteristics of fibrocartilage and hyaline cartilage, but different from the adjourning normal cartilages. The repaired cartilage in the group B was morphologically similar to fibrocartilage cartilage whereas that in group C was fibrous tissue or lamellar bone repair. There were differences between the experimental groups and the control group, as well as between both experimental groups( P ＜ 0. 05 ) .Conclusions Anatomic reconstruction of the posterior wall may help repair the defects of articular cartilage. The small cylindrical cartilage autografts may distribute throughout the articular surface, providing an alternative method to repair articular cartilage defects. Key words: Acetabulum; Bone defect; Transplantion; Articular cartilage