Diseases with Increase in Bone Mineral

Bone mineral density (BMD) in the patients with coxarthrosis (OA), ossification of posterior longitudinal ligament (OPLL), or metastatic bone tumor of prostatic cancer (PC) was examined by dual energy X-ray absorptiometry (DEXA). BMD in OA was slightly increased in the lumbar spine and total body, and markedly in the femoral neck. Factors regulating bone metabolism were in the normal range in chemical examinations. The increase in BMD in OA was considered to merely reflect the obestic tendency in those patients. BMD in OPLL was increased systemically. It seemed that some factor relating to the bone metabolism was present in OPLL. Patients with PC showed a marked elevation in BMD in metastatic portions. However, systemic BMD was higher in some cases and lower in other cases. This may depend on the volume of calcium transported from the intact bones to metastatic portions for new bone formation.