We have tested the hypothesis that the Colles' fracture is due, not simply to bone loss at the menopause, but to postural instability in a subset of postmenopausal women such that they are rendered more liable to fall. We have measured bone mass by dual photon spinal densitometry and single photon wrist densitometry and measured postural sway in 19 postmenopausal women with a history of Colles' fracture. Our results show that not only do Colles' fracture subjects have a small reduction in bone mass but they have a significantly increased degree of postural sway, a finding which has previously been recognized to characterize older subjects with recurrent falls.