Effect of oral diacerein (DAR) in an experimental hip chondrolysis model.

We aimed to reproduce the articular cartilage structural changes in a joint exposed to a metallic implant as in the adolescent pinned hip with persistent joint penetration and secondly, to test the effect of an interleukin inhibitor, diacerein (DAR) in the ensuing articular cartilage lesion. Twenty immature beagles were submitted to a surgical K-wire implantation in the hip with the material left in the joint space for 6 months. Twelve animals were sacrificed for histological and biochemical tests. Eight animals were sacrificed at 10 months (half of them treated with DAR) and analyzed by scanning electron microscopy (SEM) and biochemistry of the articular cartilage. Preoperative and monthly C3 and C4 complement and immunoglobulins serum levels were determined. The histological and the electrophoretic profile changes were significative at 6 months. At 10 months the migration profile (CaCl2) recovered to normal levels in the operated hip and the SEM scores for the acetabulum were similar to the non operated control hip after treatment. The serum level of IgA was elevated at the 4th and 6th month postoperatively. The persistence of a metallic implant resulted in degenerative changes parallel to that described for hip chondrolysis as a complication of in-situ pinning; and the cartilage lesion improved with DAR treatment.