Hip muscle size and density are associated with trochanteric fractures of elderly women

Abstract

Abstract Purpose We aimed to investigate the differences in hip muscle area and density between older patients with femoral neck (FNF) and trochanteric fractures (TRF). Methods A total of 554 older women patients were enrolled, including 314 FNF (77.02 ± 7.15 years) and 240 TRF (79.70 ± 6.91 years) for the comparisons. The area and density of the gluteus medius and minimus muscle (G.Med/MinM) and the gluteus maximus muscle (G.MaxM) were measured by CT. Total hip (TH) areal bone mineral density (aBMD) and femoral neck aBMD (FNaBMD) were measured by quantitative CT. A cutoff of 80 years was used to stratify the cohort and to further explore the age-specific relationship. Results For the total subjects, all these muscle parameters were higher in the FNF group than in the TRF group (p < 0.001). The muscle parameters except for the G.Med/MinM density were significantly correlated with hip fracture typing after adjustment for age, BMI, and THaBMD. In the age ≧ 80 group, no statistically significant correlation was found between all hip muscle parameters and fracture types. In contrast, in the age < 80 group, interestingly, after adjustment of age, BMI, and THaBMD, the associations between G.MaxM density, G.MaxM area, G.Med/MinM density, and G.Med/MinM area and fracture type were all statistically significant. Conclusions Our results indicate that in older women, especially under 80 years of age, gluteus muscle parameters are related to trochanteric fractures.