Gluteal Muscle Size and Density Linked to Trochanteric Fracture Risk in Women Under 80: Study Reveals

The study revealed that in older women, especially those under the age of 80, gluteus muscle size and density are linked to trochanteric fractures independently of BMD.

Hip fractures in older adults, including femoral neck fractures (FNF) and trochanteric fractures (TRF), lead to high morbidity, mortality, and disability. FNF has higher risks of femoral head necrosis, while TRFs are linked to increased mortality. Muscle loss with age impairs balance, raising fall risk, yet few studies compare muscle properties across fracture types while accounting for bone mineral density. To fill this knowledge gap, Pengju Huang, Department of Radiology, Beijing Jishuitan Hospital, Capital Medical University, National Center for Orthopaedics, Beijing, China, and colleagues aimed to compare hip muscle area and density in older women with femoral neck fractures and trochanteric fractures.

For this purpose, the researchers conducted a cross-sectional study at a university hospital, enrolling 554 older women, including 314 with femoral neck fractures and 240 with trochanteric fractures, for comparative analysis. The mean age of the FNF group was 77.02 ± 7.15 years, while the TRF group had a mean age of 79.70 ± 6.91 years.

CT scans measured the area and density of the gluteus medius and minimus muscles (G.Med/MinM) and the gluteus maximus muscle (G.MaxM). Quantitative CT assessed the areal bone mineral density (aBMD) of the total hip (TH) and femoral neck (FNaBMD). The participants were stratified by age, with 80 years as the cut-off, to investigate age-specific associations.

The following were the key findings of the study:

• The FNF group showed significantly higher muscle parameters compared to the TRF group.
• After adjusting for age, body mass index (BMI), and total hip aBMD (THaBMD), all muscle parameters except G.Med/MinM density were significantly associated with TRF.
• In the age ≥80 group, there were no significant correlations between hip muscle parameters and TRF.
• In the age <80 group, significant associations were observed between decreased muscle density and area of both G.MaxM and G.Med/MinM and TRF after adjustments for age, BMI, and THaBMD.

"Our study shows that in older women, especially those under 80 years of age, gluteus muscle parameters are linked to TRF. Age-related muscle loss is a known risk factor for hip fractures. Preserving muscle mass and reducing fat infiltration in muscles may play a key role in preventing TRF in this group," the researchers concluded.

Reference:

Huang P, Ge Y, Liu Y, et alAssociation between trochanteric fractures and gluteal muscle size, density in older women: a cross-sectional study at a university hospital.BMJ Open 2024;14:e086855. doi: 10.1136/bmjopen-2024-086855