The prevalence of osteoporosis in patients with hip fracture is not well defined. We performed a histomorphometric analysis of bone structural parameters in transilial biopsies of 39 patients with hip fracture (21 cervical, 18 trochanteric), 23 patients with one or more vertebral crush fractures and 20 control subjects. Trabecular bone volume (TBV) and trabecular surface density (Sv) were significantly lower in trochanteric than in cervical fractures. Mean trabecular plate thickness (MTPT), mean wall thickness (MWT) and TBV were significantly lower in trochanteric fractures than in the control group. Vertebral crush fractures are mainly characterized by a decreased TBV and Sv. There was a strong positive correlation between MWT and MTPT in trochanteric fractures suggesting that the decreased trabecular thickness in this group is due to decreased osteoblastic apposition. Trochanteric fractures are associated with serious osteoporosis, whereas cervical fractures constitute a more heterogeneous group. The osteoporosis of trochanteric fractures is characterized by significant trabecular thinning, whereas that of vertebral fractures is mainly associated with loss of trabecular plates.