Is there a place for forearm osteodensitometry in clinical screening studies?

In order to evaluate forearm osteodensitometry for its potential to detect subjects with a low spinal mineral content and/or vertebral fractures, single-photon absorptiometry of the forearm and estimations of spinal mineral content by computed tomography were performed in 124 normal and abnormal subjects. Eighty-one per cent (22/27) of patients with vertebral crush fractures had a low spinal mineral content. In contrast, among 64 apparently normal individuals, six patients (four women, two men; 9.4%) had a low spinal mineral content. Forearm osteodensitometry showed a significant positive correlation with spinal mineral content. A forearm value in women in excess of 35 arbitrary units was associated with a spinal value of 75.1-mg equivalent dipotassium phosphate (K2HPO4) or above in 29/31 cases. A forearm value in women of 28.5 arbitrary units or lower was associated with a spinal value of 75-mg equivalent K2HPO4 or less in 20/24 subjects. While of no predictive value for the spine in patients with intermediate readings, forearm osteodensitometry is nevertheless considered a useful screening procedure for spinal osteoporosis.