Osteoporosis and Fracture of the Femoral Neck

The close association of fracture of the femoral neck and osteoporosis in the aged has led to the notion that this is, in a sense, a pathological fracture. This is not a new concept. Over 100 years ago Astley Cooper (1824) noted the relationship between old age and fragility of the bones, which “. . . become thin in their shell and spongy in their texture.” More recently epidemiological studies have shown a rising incidence of fracture of the femoral neck in old age, and particularly in women after the menopause, which closely follows the age and sex distribution of osteoporosis in the populations studied (Stewart 1955, Buhr and Cooke 1959, Bauer 1960). In terms of hospital statistics and patient morbidity this is becoming an increasingly serious problem. Thus, a study carried out in the Eastern Region of Scotland suggests that the total number of patients with femoral neck fractures may be expected to increase by 50 per cent between 1952 and 1975 (Stewart 1955, 1958). It is estimated that there have been approximately 1,000 fractures of the femoral neck among the white population of three and a half million in South Africa during the past year and, given the present trend in population, this figure may be doubled by the turn of the century. Against this background there stands the casual observation that fractures of the femoral neck are apparently uncommon in the Bantu of South Africa, and the work of Jackson (1961), Seftel, Abrams, Charlton, Abrahams, Rubenstein, Jacobs and Bothwell (1963) and Walker (1965) suggests that the pattern and distribution of osteoporosis show a similar difference in the Bantu and white populations of this country. Outside South Africa, too, racial differences of this kind have been sought. Vincent and Urist (1961) and Smith, Eyler and Mellinger (1960) noted the absence of negroes among osteoporotic patients drawn from heterogeneous United States communities, and Gyepes, Mellins and Katz (1962) commented on the comparatively small number of femoral neck fractures in American negroes. However, these observations have been based on simple ratio studies of patients in hospitals or institutions. They are corroborated to some extent by the results of a demographic survey of femoral neck fractures in American negroes and whites (Bollet, Engh and Parson 1965). Unfortunately, though, in the latter study the population at risk was too small to permit definitive epidemiological analysis. The present investigation is part of a large scale epidemiological study of osteoporosis in South African populations of different racial, cultural, economic and dietary background. Further studies on vertebral and femoral osteoporosis in other population groups, both urban and rural, will be reported in due course.