Ectopic calcification in hypophosphatasia.

The radiological findings in a 24 year old female with hypophosphatasia included frayed joint surfaces, intra- and peri-articular, and paravertebral calcification. These changes were compared to the usual radiographic findings in hypophosphatasia and prompted a family study. Excessive spinal osteophytosis and/or chondrocalcinosis was a relatively frequent finding in the relatives and it is suggested that these changes might indicate the heterozygous state.