Is distal forearm fracture in men due to osteoporosis?

Although widely regarded as a disease of women, osteoporosis does cause considerable morbidity and mortality in men. The lifetime risk of an osteoporortic fracture for a man is 1 in 12 and 30% of all hip fractures occur in men. In women, low-trauma distal forearm fracture is widely regarded as a typical early manifestation of postmenopausal osteoporosis. Traditionally, this has not been thought to be the case for men. We present a case-control study of 147 men with distal forearm fracture compared with 198 age-matched controls. The controls were selected from a pre-existing database of dual-energy X-ray absorptiometry scans of healthy volunteers. Both groups were sent questionnaires regarding basic demographics, fracture history and risk factors for osteoporosis, and the fracture group was asked to attend for bone densitometry. There were 103 responses from the fracture group (70%), of whom 67 (47%) underwent densitometry. There were 165 (83%) responses from the control group. Secondary causes of osteoporosis could be identified in 51% of the fracture group and 37% of the control group. The fracture group had significantly lower bone mineral density at all sites measured compared with the controls (0.75 g/cm(2) vs 0.85 g/cm(2) at the femoral neck, p<0.0001; 0.95 g/cm(2) vs 1.03 g/cm(2) at the total femur, p = 0.001; and 0.99 g/cm(2) vs 1.06 g/cm(2) at the lumbar spine, p = 0.001). These differences remained after adjusting for age and body mass index ( p<0.0005 at all sites). Overall, 41.8% of the fracture group were osteoporotic in at least one site ( T-score <-2.5 SD below the mean for young men) compared with only 10.3% of controls. This study is the first to demonstrate that men with distal forearm fractures have lower bone mineral density than their peers and a higher risk of osteoporosis.