Lean mass and lower limb muscle function in relation to hip strength, geometry and fracture risk indices in community-dwelling older women

Abstract

SummaryIn a population-based sample of British women aged over 70 years old, lean mass and peak lower limb muscle force were both independently associated with hip strength and fracture risk indices, thereby suggesting a potential benefit of promoting leg muscle strengthening exercise for the prevention of hip fractures in postmenopausal women.IntroductionTo investigate cross-sectional associations of lean mass and physical performance, including lower limb muscle function, with hip strength, geometry and fracture risk indices (FRIs) in postmenopausal women.MethodsData were from the Cohort of Skeletal Health in Bristol and Avon. Total hip (TH) and femoral neck (FN) bone mineral density (BMD), hip geometry and total body lean mass (TBLM) were assessed by dual x-ray absorptiometry (DXA). Finite element analysis of hip DXA was used to derive FN, intertrochanteric and subtrochanteric FRIs. Grip strength, gait speed and chair rise time were measured objectively. Lower limb peak muscle force and muscle power were assessed by jumping mechanography.ResultsIn total, 241 women were included (age = 76.4; SD = 2.6 years). After adjustment for age, height, weight/fat mass and comorbidities, TBLM was positively associated with hip BMD (βTH BMD = 0.36, P ≤ 0.001; βFN BMD = 0.26, P = 0.01) and cross-section moment of inertia (0.24, P ≤ 0.001) and inversely associated with FN FRI (− 0.21, P = 0.03) and intertrochanteric FRI (− 0.11, P = 0.05) (estimates represent SD difference in bone measures per SD difference in TBLM). Lower limb peak muscle force was positively associated with hip BMD (βTH BMD = 0.28, P ≤ 0.001; βFN BMD = 0.23, P = 0.008) and inversely associated with FN FRI (− 0.17, P = 0.04) and subtrochanteric FRI (− 0.18, P = 0.04). Associations of grip strength, gait speed, chair rise time and peak muscle power with hip parameters were close to the null.ConclusionsLean mass and lower limb peak muscle force were associated with hip BMD and geometrical FRIs in postmenopausal women. Leg muscle strengthening exercises may therefore help prevent hip fractures in older women.Electronic supplementary materialThe online version of this article (10.1007/s00198-018-4795-z) contains supplementary material, which is available to authorized users.

<p>Trunk Skeletal Muscle Mass and Phase Angle Measured by Bioelectrical Impedance Analysis are Associated with the Chance of Femoral Neck Fracture in Very Elderly People</p>

“…In the past decade, BIA was widely used in analyzing body composition including segmental skeletal muscle mass with fast and non-invasive advantages, 17,18 and many of the BIA indicators were found to be valuable in helping clinicians better diagnose diseases and judge the prognosis. 19 Many previous studies have confirmed reduced aLM measured by BIA had a good correlation with increased risk of femoral neck fracture, [9][10][11] which is consolidated by our results that aLM in fracture patients is much lower than the controls. Loss of trunk skeletal muscle may be parallel to loss of appendicular skeletal muscle as people age, in which case no obvious differences can be found in fracture and controls with regarding to tSM.…”

“…7,8 Previous studies have indicated that sarcopenia is one strong risk factor for femoral neck fracture. [9][10][11] According to the definition of sarcopenia by the Asia Working Group for Sarcopenia (AWGS), 12 only appendicular lean mass (aLM) or its corrected values of the human body is used to evaluate whether sarcopenia is combined. Actually, skeletal muscles of the trunk also play an important role in maintaining posture and preventing falls.…”

The influence of antiresorptive bone medication on the effect of high-intensity resistance and impact training on osteoporotic fracture risk in postmenopausal women with low bone mass: protocol for the MEDEX-OP randomised controlled trial

“…An isometric dynamometer platform (TTM Muscular Meter, Tokyo, Japan) will be used to measure maximal isometric strength of the lower extremities 42 43. Participants will stand on the platform with their knees flexed to 115° and their back flat against the wall.…”

The effects of vitamin D supplementation on muscle strength and mobility in postmenopausal women: a systematic review and meta‐analysis of randomised controlled trials

“…A prospective 10‐year follow‐up of postmenopausal women showed that stronger back muscles could effectively reduce the risk of vertebral fractures . In addition, data from a recent cross‐sectional study reported that muscle function of the lower limbs was positively associated with hip BMD and adversely associated with geometrical fracture risk in community‐dwelling older women . Notably, functional impairment assessed by simple protocols such as grip strength can be used as a predictor of long‐term fracture risk and mortality among postmenopausal women .…”