High indices of remodelling in iliac trabecular bone predict reduced forearm cortical bone mass indices in patients with proximal femoral fractures.

To investigate whether high bone turnover could be a predictor of cortical bone loss and a candidate risk factor for fractures of the proximal femur, 33 7.5-mm transiliac biopsies taken at fracture fixation from 48 patients who participated in a study of potential risk factors have been quantitated. Twenty-four of the 33 patients made good recoveries and about 6 weeks postoperatively consented to bone densitometry of the forearm midshaft. Forearm bone density correlated negatively (r = 0.77, P = 0.001) with the surface of trabecular bone covered with osteoid, which in osteoporotic patients with crush fractures of the vertebrae was previously shown to relate both to rates of bone formation and resorption. An important minority of these femoral fracture patients appeared to be suffering from high rates of iliac trabecular bone resorption. Thus, high bone remodelling activity could lead to excessive cortical thinning. This has pathogenetic implications which may be clinically important.