Lower Jump Power Rather Than Muscle Mass Itself is Associated with Vertebral Fracture in Community-Dwelling Elderly Korean Women

Muscle parameters in fragility fracture risk prediction in older adults: A scoping review

Half of osteoporotic fractures occur in patients with normal/osteopenic bone density or at intermediate or low estimated risk. Muscle measures have been shown to contribute to fracture risk independently of bone mineral density. The objectives were to review the measurements of muscle health (muscle mass/quantity/quality, strength and function) and their association with incident fragility fractures and to summarize their use in clinical practice. This scoping review follows the PRISMA-ScR guidelines for reporting. Our search strategy covered the three overreaching concepts of 'fragility fractures', 'muscle health assessment' and 'risk'. We retrieved 14 745 references from Medline Ovid SP, EMBASE, Web of Science Core Collection and Google Scholar. We included original and prospective studies on community-dwelling adults aged over 50 years that analysed an association between at least one muscle parameter and incident fragility fractures. We systematically extracted 17 items from each study, including methodology, general characteristics and results. Data were summarized in tables and graphically presented in adjusted forest plots. Sixty-seven articles fulfilled the inclusion criteria. In total, we studied 60 muscle parameters or indexes and 322 fracture risk ratios over 2.8 million person-years (MPY). The median (interquartile range) sample size was 1642 (921-5756), age 69.2 (63.5-73.6) years, follow-up 10.0 (4.4-12.0) years and number of incident fragility fractures 166 (88-277). A lower muscle mass was positively/not/negatively associated with incident fragility fracture in 28 (2.0), 64 (2.5) and 10 (0.2 MPY) analyses. A lower muscle strength was positively/not/negatively associated with fractures in 53 (1.3), 57 (1.7 MPY) and 0 analyses. A lower muscle function was positively/not/negatively associated in 63 (1.9), 45 (1.0 MPY) and 0 analyses. An in-depth analysis shows how each single muscle parameter was associated with each fragility fractures subtype. This review summarizes markers of muscle health and their association with fragility fractures. Measures of muscle strength and function appeared to perform better for fracture risk prediction. Of these, hand grip strength and gait speed are likely to be the most practical measures for inclusion in clinical practice, as in the evaluation of sarcopenia or in further fracture risk assessment scores. Measures of muscle mass did not appear to predict fragility fractures and might benefit from further research, on D3-creatine dilution test, lean mass indexes and artificial intelligence methods.

Recreational Football Training Increases Leg-Extensor Velocity Production in 55- To 70-Year Old Adults: A Randomized Controlled Trial

This study investigated the effects of 10 weeks of recreational football training on the leg-extensor force-velocity (F-V) profile in 55- to 70-year-old adults. Simultaneous effects on functional capacity, body composition and endurance exercise capacity were examined. Forty participants (age 63.5 ± 3.9 years; 36♂ 4♀) were randomized in a football training (FOOT, n = 20) and a control (CON, n = 20) group. FOOT performed 45-min to 1-h of football training sessions with small-sided games twice a week. Pre- and post-intervention assessments were performed. The results revealed a greater increase in maximal velocity (d = 0.62, pint = 0.043) in FOOT compared to CON. No interaction effects were found for maximal power and force (pint > 0.05). 10-m fast walk improved more (d = 1.39, pint < 0.001), 3-step stair ascent power (d = 0.73, pint = 0.053) and body fat percentage (d = 0.61, pint = 0.083) tended to improve more in FOOT than in CON. RPE and HR values at the highest speed level during a submaximal graded treadmill test decreased more in FOOT compared to CON (RPE: d = 0.96, pint = 0.005; HR: d = 1.07, pint = 0.004). Both the number of accelerations and decelerations as well as the distance spent in moderate- and high-speed zones increased markedly throughout the 10-week period (p < 0.05). Participants perceived the sessions as very enjoyable and feasible. In conclusion, recreational football training resulted in improved leg-extensor velocity production, which translated to a better performance on functional capacity tests that rely on a high execution velocity. Simultaneously, exercise tolerance was improved and body fat percentage tended to reduce. It appears that short-term recreational football training can induce broad-spectrum health benefits in 55- to 70-year-old adults with only 2 hours of training per week.

Impact of relative muscle power on hospitalization and all-cause mortality in older adults

BACKGROUND

The purpose of this study was to evaluate the relationship of lower-limb muscle power with mortality and hospitalization.

METHODS

A total of 1928 subjects from the Toledo Study for Healthy Aging were included. Muscle power was assessed with the 5-repetition STS test and subjects were classified into different groups of relative power (i.e. normalized to body mass) according to sex-specific tertiles and their inability to perform the test. Mean follow-up periods for hospitalization and all-cause mortality were 3.3 and 6.3 years, respectively.

RESULTS

Compared to the high relative muscle power group, men with low (HR [95%CI]= 2.1 [1.2-3.6]) and women with very low and low (HR [95%CI]= 4.7 [3.0-7.4] and 1.8 [1.2-2.7]) relative power had an increased age-adjusted risk of hospitalization. After adjusting for several covariates (age, physical activity, BMI education, depression, comorbidities, disability and handgrip strength) these effects were attenuated (men and women with very low relative power: HR [95%CI]= 1.6 [0.9-2.9] and 2.8 [1.6-4.9]). The very low relative muscle power group had also an increased all-cause mortality risk (age-adjusted) in both men and women (HR [95%CI]= 2.3 [1.4-3.9] and 2.9 [1.6-5.3]). After adjusting for all the covariates, a significantly increased mortality risk was observed only in men (HR [95% CI]= 2.1 [1.1-3.8], (women HR [95% CI]= 1.6 [0.8-3.2]), with very low levels of relative power.

CONCLUSION

Relative muscle power was independently and negatively associated with mortality and hospitalization in older adults. An augmented all-cause mortality risk was noted in the lowest group of relative muscle power.

Computed Tomography-Derived Skeletal Muscle Radiodensity Predicts Peak Weight-Corrected Jump Power in Older Adults: The Korean Urban Rural Elderly (KURE) Study

Computed tomography (CT)-derived skeletal muscle area (SMA) and skeletal muscle radiodensity (SMD) reflect distinctive quantitative and qualitative characteristics of skeletal muscles. However, data on whether CT-based muscle parameters, especially SMD, can predict muscle function is limited. In a prospective cohort, 1523 community-dwelling older adults who underwent abdominal CT scans and the countermovement two-legged jumping test on a ground reaction force platform were analyzed (mean age 74.7 years, 65.1% women). SMA and SMD were measured at third lumbar vertebra level (L3). Individuals with low jump power (peak weight-corrected jump power < 23.8 W/kg in men and < 19.0 W/kg in women using clinically validated threshold) were older; had lower SMA, SMD, and maximal grip strength values; and had lower chair rise test and timed up and go test performance than those without low jump power. SMD was positively associated with peak weight-corrected jump power (adjusted β = 0.33 and 0.23 per 1 HU increase in men and women, respectively, p < 0.001). One HU decrement in SMD was associated with 10% elevated odds of low jump power (adjusted OR [aOR] 1.10, p < 0.001) after adjusting for age, sex, height, inflammation, and insulin resistance markers, whereas the association of SMA with low jump power was attenuated (aOR 1.00, p = 0.721). SMD showed better discrimination for low jump power than SMA (AUC 0.699 vs. 0.617, p < 0.001), with additional improvement when added to SMA and conventional risk factors (AUC 0.745 to 0.773, p < 0.001). Therefore, CT-measured L3 SMD can be a sensitive surrogate marker for muscle function along with SMA in older adults, which merits further investigation.

Bipedal hopping as a new measure to detect subtle sensorimotor impairment in people with multiple sclerosis

BACKGROUND

Bipedal hopping has the potential to detect subtle multiple sclerosis (MS)-related impairments, especially among patients who "pass" typical movement tests. In this narrative review, we outline the biomechanics of bipedal hopping and propose its usefulness as a novel outcome measure for people with MS having mild disability.

METHODS

We summarize articles that (1) examined the biomechanics of jumping or hopping and (2) tested the validity and/or reliability of hopping tests. We consolidated consistencies and gaps in research and opportunities for future development of the bipedal hop test.

RESULTS

Bipedal hopping requires immense power, coordination, balance, and ability to reduce co-contraction; movement components typically affected by MS. These impairments can be measured and differentiated by examining specific variables, such as hop length (power), symmetry (coordination), center of pressure (balance), and coefficient of variability (co-contraction/spasticity). Bipedal hopping challenges these aspects of movement and exposes sensorimotor impairments that may not have been apparent during walking.

CONCLUSIONS

Testing of bipedal hopping on an instrumented walkway may detect and monitor sensorimotor control in people with MS who do not currently present with clinical deficits. Early measurement is imperative for precise rehabilitation prescription to slow disability progression prior to onset of measurable gait impairment.Implications for rehabilitationJumping and hopping tests detect lower limb and balance impairments in children, athletes, and older adults.Bipedal hop test measures multiple domains: power, coordination, balance, and muscle timing.Bipedal hop test may expose subtle sensorimotor impairments in people with multiple sclerosis.Multiple variables measured can discern type of sensorimotor impairment to direct personalized rehabilitation programs.

Decline in Muscle Strength and Performance Predicts Fracture Risk in Elderly Women and Men

CONTEXT

Muscle strength and performance are associated with fractures. However, the contribution of their rate of decline is unclear.

OBJECTIVE

To assess the independent contribution of the rate of decline in muscle strength and performance to fracture risk.

DESIGN, SETTING, AND PARTICIPANTS

Community-dwelling women (n = 811) and men (n = 440) aged 60 years or older from the prospective Dubbo Osteoporosis Epidemiology Study followed from 2000 to 2018 for incident fracture. Clinical data, appendicular lean mass/height2 (ht)2, bone mineral density, quadricep strength/ht (QS), timed get-up-and-go (TGUG), 5 times repeated sit-to-stand (5xSTS), and gait speed (GS) measured biennially. Rates of decline in muscle parameters were calculated using ordinary least squares regression and fracture risk was assessed using Cox's models.

MAIN OUTCOME

Incident low-trauma fracture ascertained by x-ray report.

RESULTS

Apart from lean mass in women, all muscle parameters declined over time. Greater rates of decline in physical performance were associated with increased fracture risk in women (Hazard ratios [HRs] ranging from 2.1 (95% CI: 1.5-2.9) for GS to 2.7 (95% CI: 1.9-3.6) for 5xSTS, while in men only the decline in GS was associated with fracture risk (HR: 3.4 [95% CI: 1.8-6.3]). Baseline performance and strength were also associated with increased fracture risk in men (HRs ranging from 1.8 (95% CI: 1.1-3.0) for QS to 2.5 (95% CI: 1.5-4.1) for TGUG, but not in women.

CONCLUSION

Rate of decline in physical performance in both genders, and baseline strength and performance in men, contributed independently to fracture risk. Sit-to-stand and GS were the tests most consistently associated with fractures. Further studies are required to determine whether muscle strength and/or performance improve the predictive accuracy of fracture prediction models.

Predicting radiological vertebral fractures with a combined physical function and body composition scoring system

The objective of this study was to investigate the incidence of vertebral fractures (VFx) and the value of physical function (PF) and body composition (BC) for predicting VFx in a Japanese population. This study included 307 subjects (113 men, 194 women) at least 40 years of age who were assessed at community health check-ups in 2008 and 2016. PF was assessed by grip strength and by single-leg stance, timed up-and-go, and 30-s chair stand tests, each scored from 0 to 3 for a possible total of 12 points (higher scores reflect lower function). BC was scored on bioelectrical impedance measurements of trunk and appendage muscle volume, with 6 possible points. We diagnosed radiological VFx semiquantitatively on lateral views of the lumbar spine, and measured bone mineral status by quantitative ultrasound (QUS) of the calcaneus. We conducted logistic regression analysis with VFx as the dependent variable and age, sex, BMI, QUS, PF score, and BC score as independent variables. In 8 years, 36 participants (12%) sustained new VFx. After correcting for age, sex, BMI, and QUS, the odds of VFx increased with a PF score ≥ 8 (OR 5.6; 95% CI 1.21-25.90; P = 0.028) and increased further with a PF + BC score ≥ 9 (OR 8.1; 95% CI 1.80-36.00; P < 0.01). Both PF and BC are important for predicting fragility fractures. The scoring system used here may reflect small differences better than categorical (single cutoff) definitions of poor function.

Dysmobility syndrome is associated with prevalent morphometric vertebral fracture in older adults: the Korean Urban-Rural Elderly (KURE) study

In a community-dwelling elderly cohort, dysmobility syndrome was associated with elevated odds of morphometric vertebral fracture or any prevalent fracture, independent of age and covariates. Dysmobility syndrome improved discrimination for fracture when added to the FRAX score.

INTRODUCTION

Dysmobility syndrome was coined to indicate patients with impaired musculoskeletal health. Data on the association of dysmobility syndrome with prevalent morphometric vertebral fracture (VF) in elderly persons are limited.

METHODS

A total of 1369 community-dwelling elderly subjects (mean age 71.6 years; women 66%) were analyzed. Dysmobility syndrome was defined as ≥ 3 components among falls, low lean mass, high fat mass, osteoporosis, low grip strength, and low timed get-up-and-go performance. VF was defined as a ≥ 25% reduction in the height of vertebral bodies in plain radiographs. Modified cutpoints of each component at which elevate the odds of fracture were investigated using receiver-operating characteristics analysis. Net reclassification improvement (NRI) and integrated discrimination index (IDI) were calculated to assess additive discriminatory value of dysmobility syndrome over FRAX.

RESULTS

The prevalence of VF and any fracture composite of VF and non-VF was 16% and 25%, respectively, increasing according to number of dysmobility components (from 0 to 5; VF 10-35%; any fracture 16-45%). Dysmobility syndrome was associated with elevated odds of VF (adjusted OR [aOR] 1.52, 95% CI 1.08-2.15) or any fracture (aOR 1.46, 95% CI 1.07-1.98) but no longer with non-VF (aOR 1.31, 95% CI 0.86-1.98) in multivariate model, whereas modified definition showed robust association with non-VF (aOR 1.79, 95% CI 1.23-2.60). Dysmobility syndrome improved discrimination for prevalent fracture when added to FRAX (NRI 0.25, 95% CI 0.13-0.37; IDI 0.020, 95% CI 0.014-0.026).

CONCLUSIONS

Dysmobility syndrome was associated with elevated odds of morphometric VF in community-dwelling older adults, independent of age and covariates.

Low physical performance determined by chair rising test muscle mechanography is associated with prevalent fragility fractures

This study examined associations between physical performance assessed by chair rising test muscle mechanography and DXA T-score as well as body composition in a large patient cohort. Next to various significant interrelationships between these muscle and bone parameters, lower physical performance was associated with prevalent fragility fractures.

PURPOSE

Although the interaction between muscle and bone has been demonstrated in various aspects, the clinical focus in the diagnosis of musculoskeletal disorders mainly lies on the skeletal assessments. Accordingly, the association between muscle function, bone mineral density (BMD), and fragility fractures remains to be further elucidated with a feasible muscle assessment in a clinical setting.

METHODS

Patient data (2076 patients, 1538 women, 538 men) were evaluated retrospectively from a large dual energy X-ray absorptiometry (DXA) database as well as from chair rising test (CRT) that was performed on a muscle mechanograph. To determine potential predictors of the CRT time and maximum force, a multivariate regression analysis was performed including age, DXA T-score, and body composition indices. Furthermore, CRT results were compared between non-fracture and fracture cases.

RESULTS

We determined independent predictors for CRT time such as age, femoral DXA T-score, and total fat mass, whereas CRT force was only influenced by total lean mass. Both women and men with previous fragility fractures displayed a longer CRT time (women p = 0.009, men p = 0.001) and lower CRT force (women p < 0.001, men p < 0.001) than those with no fractures, while no clear differences in CRT results could be detected between normal BMD, osteopenia, and osteoporosis based on DXA T-scores.

CONCLUSIONS

Our study demonstrates that in addition to the associations between chair rising time and femoral T-score assessed by DXA, low muscle strength is associated with previous fragility fractures.

Low peak jump power is associated with elevated odds of dysmobility syndrome in community-dwelling elderly individuals: the Korean Urban Rural Elderly (KURE) study

In a community-dwelling elderly cohort (Korean Urban Rural Elderly), low peak jump power was associated with elevated odds of dysmobility syndrome and its components, independent of age and comorbidities. Jump power measurement improved discrimination of individuals with dysmobility syndrome when added to conventional risk factors.

INTRODUCTION

Dysmobility syndrome was proposed to encompass the risks affecting musculoskeletal outcomes. Jump power measurement is a safe, reproducible high-intensity test for physical function in elderly. However, the relationship between jump power and dysmobility syndrome remains unknown.

METHODS

A total of 1369 subjects (mean 71.6 years; women, 66%) were analyzed from a community-based cohort. Dysmobility syndrome was defined as the presence of ≥ 3 factors among falls in the preceding year, low lean mass, high fat mass, osteoporosis, low grip strength, and low timed get-up-and-go (TUG) performance. Subjects were grouped into tertiles of jump power relative to weight based on sex-stratified cutoffs (32.4 and 27.6 W/kg in men; 23.9 and 19.9 W/kg in women) or into the failed-to-jump group.

RESULTS

The prevalence of dysmobility syndrome was 20% overall, increasing from the highest (T1) to lowest (T3) jump power tertile (1, 11, 15% in men; 11, 16, 39% in women) and the failed-to-jump group (39% in men; 48% in women). Low jump power or failed-to-jump was associated with elevated odds of dysmobility syndrome (T3 vs. T1, adjusted odds ratio [aOR] 4.35, p < 0.001; failed-to-jump vs. T1, aOR 7.60, p < 0.001) and its components including falls, low lean mass, high fat mass, and poor TUG performance but not osteoporosis after adjustment for covariates. Jump power modestly discriminated dysmobility syndrome (area under the curve [AUC], 0.71, p < 0.001), which improved discriminatory performance when added to conventional risk factors (AUC, from 0.75 to 0.79, p < 0.001).

CONCLUSIONS

Low peak jump power was associated with elevated odds of dysmobility syndrome and its components, independent of age and comorbidities.