Purpose: The purpose of this study was to investigate specific risk factors, common fracture locations and possible sex-specific differences in elderly patients with stress fractures.
Methods: This analysis enrolled 105 patients (83 women, 22 men) with stress fractures. For the analysis of possible risk factors related to increasing age, data from 82 patients (67 women, 15 men) aged 40 years and older (mean age of 57.4 ± 11.0 years) were compared with that from a younger control group [23 patients (16 women, seven men), mean age 28.4 ± 6.7 years]. Bone mineral density (BMD) was determined using dual-energy X-ray absorptiometry bone densitometry (DXA) and blood samples were taken.
Results: A total of 211 stress fractures were found. Of these, 177 were found in the study group, of which 90.4 % were located in the lower limb. Lumbar and femoral BMD was significantly lower in elderly patients; however, the BMD of most patients was within the osteopenic or normal range. Within the study group, a total of 83.8 % had a vitamin D insufficiency (<30 μg/l); 75.5 % were not engaged in regular physical activity more than once a week. Overweight patients within the study group had significantly more stress fractures compared to normal weight patients (2.6 ± 1.7 vs. 1.9 ± 1.1, p<0.05).
Conclusions: A similar contribution of risk factors has been found for stress fractures in elderly patients and younger controls of the general population. Stress fracture incidence seems to be rather multifactorial and not based on osteoporotic changes alone. A balanced calcium and vitamin D metabolism seems to be of paramount importance for stress fracture prevention in elderly patients.