Thigh Muscle Composition and Its Relationship to Functional Recovery Post Hip Fracture Over Time and Between Sexes

Abstract

Background CT-scan measures of muscle composition may be associated with recovery post hip fracture. Methods In an ancillary study to Baltimore Hip Studies 7th cohort, older adults were evaluated at 2 and 6 months post-hip fracture. CT-scan measures of muscle were acquired at 2 months. Short Physical Performance Battery (SPPB) was measured at 2 and 6 months. Generalized estimating equations were used to model the association of muscle measures and physical function, adjusting for age, sex, BMI, and time post fracture. Results Seventy-one older adults (52% males, age 79.6 ± 7.3 yrs) were included. At 2-months, males had greater thigh cross-sectional area (CSA, p<0.0001) and less low density muscle (p=0.047), and intermuscular adipose tissue (p=0.007) than females on the side of the fracture, while females performed better on the SPPB (p= 0.05). Muscle measures on the fractured side were associated with function at 2 months in both sexes. Subjects in the lowest tertile of muscle CSA difference at 2-months, indicating greater symmetry in CSA between limbs, performed better than the other two tertiles at 6-months. Males performed worse in functional measures at baseline and did not recover as well as females (p= 0.02). Conclusions CT-scan measures of muscle CSA and fatty infiltration were associated with function at 2-months post-hip fracture and with improvement in function by 6 months. Observed sex differences in these associations suggest that rehabilitation strategies may need to be adapted by sex after hip fracture.

Shape phenotype of thigh fat and muscle and risk of major adverse cardiovascular events after fragility hip fracture

“…17 Although there have been some studies exploring the prognostic value of thigh composition in elderly patients with hip fracture, they have focused on predicting surgical complication, functional recovery or mortality rather than adverse CV events. [18][19][20] Few studies have examined the relationship between thigh fat and muscle measurements and CV outcomes following hip fracture. Given that pelvic bone computed tomography (CT) is routinely performed as an initial examination for suspected hip fracture, this opportunistic measurement of thigh composition without additional exposure to radiation is practical and reliable.…”

“…Although there have been some studies exploring the prognostic value of thigh composition in elderly patients with hip fracture, they have focused on predicting surgical complication, functional recovery or mortality rather than adverse CV events 18–20 . Few studies have examined the relationship between thigh fat and muscle measurements and CV outcomes following hip fracture.…”