We studied the histomorphometry of the trabecular bone of 19 black men and 15 black women over the age of 60 years who had sustained fractured neck of femur (FNF) as a result of minor trauma. The findings were correlated with indicators of iron overload (ferritin and vitamin C).

A striking feature was the presence of iron granules in the bone marrow of 16 of the men and nine of the women, together with fibrosis. Present in large numbers, the granules were quantitated. There were significantly more iron granules in the men than in the women (p =0.05). Ferritin levels were higher in those patients with large numbers of granules than in those with few or no granules. There was no clear correlation with the indicators, bone formation or resorption.

We concluded that iron overload is a strong aetiological factor in black male FNF patients. In postmenopausal female FNF patients, the possible aetiological role of iron overload is complicated by hormone deficiency.

Among elderly Caucasians, fractures of the femoral neck are a common cause of disability. Intertrochanteric and intra-capsular fractures occur equally often, and both are about three times more common in women than in men. Risk factors include neurological impairment, malnutrition, impaired vision, malignancy and decreased activity.

We found that in black South Africans femoral neck fractures occur equally often in men and in women. Intracapsular fractures are comparatively rare, occurring in one of every eight female patients and one of every 3.5 male patients. Further, we found that in both black men and black women the femoral neck was consistently and significantly shorter than in whites.

These results suggest that a short femoral neck may offer protection not only against intracapsular fracture, but also possibly against fracture of the femoral neck in general. In addition, greater cortical thickness in black people probably offers further protection.

We studied the bone density and bone mineral content of 14 men and 10 women over the age of 60 years who had sustained a femoral neck fracture as a result of minor trauma. They were matched for age and gender with controls from a peri-urban black population.

Among the men, the femoral T and Z scores were significantly lower in the patients than in the controls. There were no significant differences among the female patient and control groups. In the controls, the mean bone densities were lower than in hologic white controls. The differences were not age-related. The black female controls also had lower bone densities than hologic white controls. These densities fell rapidly after the age of 50 years and this was age-related. As measured by their T scores, most of the patients were at risk for fractures.