A 73-year-old woman presented with rapidly destructive changes of the knee joint due to calcium pyrophoshate dihydrate crystal deposition disease. The patient was complaining of pain and swelling of the left knee joint. She became progressively limited in movement and got around using crutches with difficulty. Radiographs showed osteoarthritic changes and chondrocalcinosis in the knees, shoulders, and hips. On X-ray, the left knee showed destructive changes affecting the medial femoral condyle and tibial plateau on June sixth, 1996. On July forth the destructive change was more marked and on August eighth gross destruction had occurred. Investigations showed a normal erythrocyte sedimentation rate (ESR), serum calcium, and alkaline phosphate. The serological test for syphilis was negative and no increase in rheumatoid factor was found. Deep pain sensation was normal and there were no abnormal neurological signs. We performed total joint replacement with bone graft of the left knee joint. At the operation, calcium pyrophosphate dihydrate crystals were found in the meniscus. After the operation, the left knee joint was stable and painless.
