Comparisons were made between 133 men with cervical fractures and 151 men with trochanteric fractures and 308 women with cervical fractures and 449 women with trochanteric fractures. All patients with hip fractures were studied consecutively and prospectively. Patients were interviewed a few days after admission and their medical records studied. We found great differences in background factors between patients with cervical and trochanteric fractures but these differences seemed to depend largely on age. In an age-matched material we find that patients with trochanteric fractures are more prone to such fragility fractures as vertebral fracture, trochanteric fracture and fracture of the upper end of the humerus. This could mean that trochanteric fractures occur in bone of lower trabecular mass.