Feasibility, acceptability and prognostic value of muscle mass and strength measurement in patients with hip fracture: a systematic review

Key summary points Aim We systematically reviewed whether muscle mass measurement was independently associated with adverse outcomes in patients with hip fracture. Our secondary aim was to systematically review whether muscle mass assessment was feasible and acceptable in this cohort. Findings There are no studies specifically assessing feasibility and acceptability of muscle mass assessment in patients with hip fracture. Low muscle mass is associated with increased mortality, worse mobility and physical performance in unadjusted analyses. Message Included studies suggest muscle mass offers no additional prognostic benefit to muscle strength when assessing sarcopenia in acute hip fracture. Purpose Sarcopenia is diagnosed on the basis of low muscle strength, with low muscle mass used to confirm diagnosis. The added value of measuring muscle mass is unclear. We undertook a systematic review to assess whether muscle mass measurement in patients with hip fracture was acceptable, feasible and independently associated with adverse outcomes. Methods Electronic databases (MEDLINE, EMBASE, CENTRAL, CINAHL, Clinicaltrials.gov) were searched for studies of patients with hip fracture aged ≥ 60 with perioperative muscle mass or strength assessments. Associations with postoperative outcomes including death, length of stay and activities of daily living were extracted. Risk-of-bias was assessed using the AXIS and ROBINS-I tools. Due to the degree of study heterogeneity, data were analysed by narrative synthesis. Results The search strategy identified 3317 records. 36 studies were included with 7860 participants. Acceptability of muscle mass measurement was not assessed, but measurement appeared feasible using biompedance, dual energy x-ray absorptiometry and computed tomography. Univariate analyses indicated that lower muscle mass was associated with higher death rates at 30 days, worse mobility, worse activity of daily living metrics and worse physical performance but there was no significant association with length of stay or postoperative complications. Four studies included both muscle mass and strength in multivariable analyses; muscle mass was a significant independent predictor of only one adverse outcome in a single study after adjustment for muscle strength and other predictor variables. Conclusion Current data suggest that muscle mass assessment offers no additional prognostic information to muscle strength measures in patients with hip fracture.