Rapidly destructive arthropathy of the hip. Studies on bone resorptive factors in joint fluid with a theory of pathogenesis.

The mechanism of joint destruction in rapidly destructive coxopathy was studied by analyzing bone resorptive factors in the joint fluid. Prostaglandins were found to play a partial role in joint destruction. Some cases of rapidly destructive coxopathy revealed elevated levels of interleukin-1 beta (IL-1 beta) in the joint fluid. Electrophoretic analysis of proteolytic enzymes in polyacrylamide gel containing sodium dodecyl sulfate and copolymerized gelatin demonstrated that the resorptively active peptides have relative molecular weights (M(r)) of approximately 92,000, 72,000, and lower than 60,000. Cultured cells from synovia obtained perioperatively secreted matrix metalloproteinase 2 (MMP-2) with an M(r) of 72,000 and matrix metalloproteinase 3(MMP-3) with an M(r) of 57,000. Synovial cells from the patients with coxarthrosis secreted fewer proteolytic enzymes. Prostaglandins, IL-1 beta, MMP-2, and MMP-3 could act synergetically as promotors in the rapid destruction of the hip joint.