Catherine M. Arnold

The history of falls and the association of the timed up and go test to falls and near-falls in older adults with hip osteoarthritis

BackgroundFalling accounts for a significant number of hospital and long-term care admissions in older adults. Many adults with the combination of advancing age and functional decline associated with lower extremity osteoarthritis (OA), are at an even greater risk. The purpose of this study was to describe fall and near-fall history, location, circumstances and injuries from falls in a community-dwelling population of adults over aged 65 with hip OA and to determine the ability of the timed up and go test (TUG) to classify fallers and near-fallers.MethodA retrospective observational study of 106 older men and women with hip pain for six months or longer, meeting a clinical criteria for the presence of hip OA at one or both hips. An interview for fall and near-fall history and administration of the TUG were administered on one occasion.ResultsForty-five percent of the sample had at least one fall in the past year, seventy-seven percent reported occasional or frequent near-falls. The majority of falls occurred during ambulation and ascending or descending steps. Forty percent experienced an injury from the fall. The TUG was not associated with history of falls, but was associated with near-falls. Higher TUG scores occurred for those who were older, less mobile, and with greater number of co-morbidities.ConclusionA high percentage of older adults with hip OA experience falls and near-falls which may be attributed to gait impairments related to hip OA. The TUG could be a useful screening instrument to predict those who have frequent near-falls, and thus might be useful in predicting risk of future falls in this population.

The reliability and validity of handheld dynamometry for the measurement of lower-extremity muscle strength in older adults.

Arnold, CM, Warkentin, KD, Chilibeck, PD, and Magnus, CRA. The Reliability and Validity of Handheld Dynamometry for the Measurement of Lower-Extremity Muscle Strength in Older Adults. J Strength Cond Res 24(3): 815-824, 2010-Lower-extremity muscle strength is important in predicting fall risk in older adults. Handheld dynamometry (HHD) is a tool used to measure isometric muscle strength in the older adult, but few studies have evaluated the utility of HHD for muscle groups beyond knee extension. The purpose of this study was to evaluate the reliability of HHD at the hip, knee, and ankle and to compare HHD strength values to other isometric dynamometry (ID) and to balance and recovery in older adults. This was a repeated measures study design of 18 men and women, age 65 to 92 years of age, who had HHD strength testing 3 to 7 days apart by the same examiner and repeat testing on the same day using 2 independent examiners. ID strength, balance, step length, and reaction time were measured once. HHD demonstrated good intrarater and interrater reliability for isometric strength at the hip and knee but was not a reliable measure for ankle strength. The HHD was a valid measure of isometric strength at the hip and knee, demonstrating moderate to high correlation values when compared to ID strength measures (r = 0.57-0.86; p < 0.05). Hip and knee strength was positively associated to step length and reaction time but not to balance (r = 0.40-0.71; p < 0.05). In conclusion, HHD is a reliable and valid assessment tool for measuring strength at the hip and knee in older adults, and greater strength in these muscles is associated with longer step length and decreased reaction time, which are important components of balance recovery in older adults. HHD can be used as an effective strength measurement tool for the older adult population.

A Randomized Clinical Trial of Aquatic versus Land Exercise to Improve Balance, Function, and Quality of Life in Older Women with Osteoporosis

PURPOSE Despite the decreased gravitational loading that is experienced in an aquatic environment, little research has been conducted on this exercise medium for women with osteoporosis (OP). Aquatic exercise (AE) may improve function and balance, thus ultimately decreasing fall risk and the potential for hip fractures in this high-risk population. METHOD A total of 68 women with OP, aged 60 years or older, were recruited into a randomized clinical trial evaluating the impact of AE, land exercise (LE), and no exercise (NE) on balance, functional mobility, and quality of life (QOL). RESULTS Only one balance measure (backward tandem walk) significantly improved with AE compared to LE, but this did not translate into a greater improvement in self-report function. There were no significant differences between the exercise interventions and NE, except for in ratings of global change, where participants in the AE group were three times more likely to report improvement than those in the NE group. CONCLUSION There were no differences in balance, function, or QOL in women with OP who followed an AE or LE programme compared to those in an NE control group. However, the significant differences in backward tandem walk between the AE and LE groups and self-reported global change between the AE and NE groups warrant further investigation. Significant improvements in balance and global change suggest that AE is a viable alternative for older women with OP who have difficulty exercising on land.

Exercise for Fall Risk Reduction in Community-Dwelling Older Adults: A Systematic Review

PURPOSE To evaluate the influence of exercise on falls and fall risk reduction in community-dwelling older adults and to present an updated synthesis of outcome measures for the assessment of fall risk in community-dwelling older adults. METHOD A systematic review was performed, considering English-language articles published from 2000 to 2006 and accessible through MEDLINE, CINAHL, PEDro, EMBASE, and/or AMED. Included were randomized controlled clinical trials (RCTs) that used an exercise or physical activity intervention and involved participants over age 50. Screening and methodological quality for internal validity were conducted by two independent reviewers. RESULTS The search retrieved 156 abstracts; 22 articles met the internal validity criteria. Both individualized and group exercise programmes were found to be effective in reducing falls and fall risk. The optimal type, frequency, and dose of exercise to achieve a positive effect have not been determined. A variety of outcome measures have been used to measure fall risk, especially for balance. CONCLUSIONS Falls and fall risk can be reduced with exercise interventions in the community-dwelling elderly, although the most effective exercise variables are unknown. Future studies in populations with comorbidities known to increase fall risk will help determine optimal, condition-specific fall-prevention programmes. Poor balance is a key risk factor for falls; therefore, the best measure of this variable should be selected when evaluating patients at risk of falling.

Risk Factors for Falls in Older Adults with Lower Extremity Arthritis: A Conceptual Framework of Current Knowledge and Future Directions

PURPOSE As the numbers of Canadians aged 65 years and over increases over the next 20 years, the prevalence of chronic conditions, including arthritis, will rise as will the number of falls. Although known fall-risk factors are associated with hip and knee osteoarthritis (OA), minimal research has evaluated fall and fracture risk and/or rates in this population. Thus, the purpose was to summarize research on fall and fracture risk in older adults with hip or knee OA and to develop a conceptual framework of fall-risk screening and assessment. METHOD The International Classification of Functioning, Disability and Health, clinical practice guidelines for fall-risk screening, and a selected literature review were used. RESULTS Gaps exist in our knowledge of fall and fracture risk for this population. Muscle performance, balance, and mobility impairments have been identified, but little is known about whether personal and environmental contextual factors impact fall and fracture risk. Physical activity may help to prevent falls, but non-adherence is a problem. CONCLUSION A need exists to assess fall risk in older adults with hip and knee OA. Promoting regular physical activity by focusing on disease- and activity-specific personal contextual factors may help direct treatment planning.

Former premenarcheal gymnasts exhibit site-specific skeletal benefits in adulthood after long-term retirement.

Young female gymnasts have greater bone strength compared to controls; although possibly due to selection into gymnastics, it is thought that their loading activity during growth increases their bone mass, influencing both bone geometry and architecture. If such bone mass and geometric adaptations are maintained, this may potentially decrease the risk of osteoporosis and risk of fracture later in life. However, there is limited evidence of the persisting benefit of gymnastic exercise during growth on adult bone geometric parameters. Therefore, the purpose of this study was to determine whether adult bone geometry, volumetric density, and estimated strength were greater in retired gymnasts compared to controls, 10 years after retirement from the sport. Bone geometric and densitometric parameters, measured by peripheral quantitative computed tomography (pQCT) at the radius and tibia, were compared between 25 retired female gymnasts and 22 controls, age range 22 to 30 years, by multivariate analysis of covariance (covariates: age, height, and muscle cross‐sectional area). Retired gymnasts had significantly greater adjusted total and trabecular area (16%), total and trabecular bone mineral content (BMC) (18% and 22%, respectively), and estimated strength (21%) at the distal radius (p < 0.05) than controls. Adjusted total and cortical area and BMC, medullary area, and estimated strength were also significantly greater (13% to 46%) in retired gymnasts at the 30% and 65% radial shaft sites (p < 0.05). At the distal tibia, retired gymnasts had 12% to 13% greater total and trabecular BMC and volumetric bone mineral density as well as 21% greater estimated strength; total and cortical BMC and estimated strength were also greater at the tibial shaft (8%, 11%, and 10%, respectively) (p < 0.05). Former female gymnasts have significantly better geometric and densitometric properties, as well as estimated strength, at the radius and tibia 10 years after retirement from gymnastics compared to females who did not participate in gymnastics in childhood and adolescence.

The Relationship between Falls Efficacy and Improvement in Fall Risk Factors Following an Exercise Plus Educational Intervention for Older Adults with Hip Osteoarthritis

PURPOSE Older adults with decreased confidence in their ability to prevent a fall may benefit from an exercise programme that includes self-efficacy-enhancing education. The objectives of this study were to explore differences in fall-risk outcomes in older adults with higher vs. lower levels of falls efficacy and to evaluate the relationship between baseline falls-efficacy status and changes in fall risk factors following two interventions. METHOD Fifty-four older adults with hip osteoarthritis and at least one risk factor for falls received aquatic exercise twice weekly plus education once weekly (EE) or aquatic exercise only, twice weekly (EO), for 11 weeks. RESULTS EE participants with low baseline falls efficacy demonstrated significantly (p<0.05) greater improvement in balance and falls efficacy compared to EE participants with high baseline falls efficacy. In the EE group only, baseline falls-efficacy status (low vs. high median split on the Activities-specific Balance Confidence Scale) was significantly (p<0.05) correlated with positive balance and falls-efficacy change scores (Spearman rank r=0.45 and 0.63 respectively). CONCLUSIONS Individuals with one or more fall-risk factors and low falls efficacy may benefit from receiving an intervention that combines exercise with self-efficacy-enhancing education. Falls-efficacy screening may be important for decisions regarding referral to fall-prevention programmes.

Community-dwelling female fallers have lower muscle density in their lower legs than non-fallers: evidence from the Saskatoon Canadian Multicentre Osteoporosis Study (CaMos) cohort

ObjectiveOur objectives were to determine whether peripheral quantitative computed tomography (pQCT)-derived lower leg muscle density and area, and basic functional mobility differ between communitydwelling older women who do and do not report recent falls.DesignMatched case-control comparison.SettingAcademic biomedical imaging laboratory.Participants147 Women, 60 years or older (mean age 74.3 y, SD 7.7) recruited from a longitudinal, population-based cohort representing community-dwelling residents in the area of Saskatoon, Canada.MeasurementsA cross-sectional pQCT scan of the non-dominant lower leg was acquired to determine muscle density and area. Basic functional mobility (Timed Up and Go Test [TUG]) and SF36 health status were also measured. Fallers (one or more falls) and non-fallers (no falls) were grouped according to a 12-month retrospective survey and matched on measured covariates.ResultsThe muscle density of fallers (n = 35) was a median of 2.1 mg/cm3 lower (P = 0.019, 95% C.I. −3.9 to −0.1) than non-fallers (n = 78) after matching and adjusting for age, body mass index, and SF36 general health scores. Muscle area and TUG did not differ between fallers and non-fallers.ConclusionMuscle density may serve as a physiological marker in the assessment of lower leg muscular health and fall risk in community-dwelling elderly women. These results are limited to our study population who were mostly Caucasian. Prospective studies are required for verification.

Does Falls-Efficacy Predict Balance Performance in Older Adults with Hip Osteoarthritis?

This cross-sectional study evaluated the relationship of falls-efficacy to physical performance of functional balance tasks in older adults with hip osteoarthritis (OA). Older adults with hip OA experience several factors associated with fall risk: loss of movement, loss of strength, and increased fear of falls. Seventy-nine men and women age 65 or older were measured for balance, dual task function, and falls-efficacy. Using hierarchical regression, falls-efficacy was a significant predictor of balance when number of medications, age, use of a walking aid, health status, and physical activity level were controlled for. Understanding the role of falls-efficacy in predicting fall risk helps clinicians develop falls screening and prevention programs.

The Relationship of Knee-Extensor Strength and Rate of Torque Development to Sit-to-Stand Performance in Older Adults

PURPOSE To investigate the association of knee-extensor strength and power to performance in the 30-second sit-to-stand test (30sSTS) in healthy older adults. METHOD In a cross-sectional study of 29 healthy older adults aged 60-82 years (12 male, 17 female), hierarchical regression was used to determine the relationship of knee-extensor concentric and eccentric strength, peak rate of torque development (peak RTD) using isokinetic dynamometry, and momentum variables with the number of sit-to-stand repetitions completed in 30 seconds (30sSTSreps). RESULTS Concentric (180°/s) and eccentric (90°/s) knee-extensor strength were significant independent predictors of 30sSTSreps after controlling for physical activity level, height and weight (adjusted R (2)=0.425, p=0.004; adjusted R (2)=0.427, p=0.004 respectively), as was concentric (90°/s) knee-extensor peak RTD (adjusted R (2)=0.424, p=0.004). Peak linear vertical momentum (PLVM) (adjusted R (2)=0.615, p<0.001) accounted for 36% of the variance. CONCLUSIONS Generation of PLVM is an important predictor of 30sSTSreps; knee-extensor concentric and eccentric strength and power are associated with improved performance in this common functional task. Focusing on these parameters in exercise interventions may improve functional performance and give insight into specific factors related to success on the test.