Biomedical subjects

Sandra J Olney

Publications and source records attributed to Sandra J Olney.

7 recordsLinked to original sources

PubMed2006

Role of knee kinematics and kinetics on performance and disability in people with medial compartment knee osteoarthritis.

BACKGROUND: Although gait characteristics have been well documented in people with knee osteoarthritis, little is known about the relationships between gait characteristics and performance or disability. Our purpose was to examine the role of knee kinematics and kinetics on walking performance and disability in people with knee osteoarthritis. We also examined whether pain mediated the relationship between the knee adduction moment and performance or disability. METHODS: Three-dimensional gait analysis was conducted on 54 people with medial compartment knee osteoarthritis. Performance was quantified with the Six Minute Walk test and disability was self-reported on the Short Form-36. The pain subscale of the Western Ontario McMaster Universities Osteoarthritis Index and the functional self-efficacy subscale of the Arthritis Self-Efficacy scale were completed. FINDINGS: A step-wise linear regression demonstrated that the variance in Six Minute Walk test scores was explained by functional self-efficacy (50%) and the range of knee motion (8%). The variance in Short Form-36 was explained by pain (36%), the peak extension angle (19%) and the range of knee motion (4%). Pain was unrelated to the knee adduction moment so analyses of pain as a mediator of the adduction moment on either performance or disability were halted. INTERPRETATION: Kinematic output from the motor control system is useful in understanding some variance in current performance and disability in people with knee osteoarthritis. The knee adduction moment was unrelated to these variables and pain did not mediate between the knee adduction moment and performance or disability. Therefore this moment does not explain current clinical status in people with knee osteoarthritis based on the measures of performance and disability used in this study.

Aged↗

PubMed2006

Determinants of self efficacy for physical tasks in people with knee osteoarthritis.

OBJECTIVE: Self efficacy, the confidence an individual has to perform a task, is an important determinant of physical performance in individuals with knee osteoarthritis (OA). The purpose of this study was to determine what personal, pathophysiologic, and impairment factors relate to self efficacy for physical tasks in community-dwelling adults with knee OA. METHODS: Fifty-four persons with radiographically confirmed knee OA (mean +/- SD age 68.3 +/- 8.7 years, range 50-87 years) participated. The Functional Self-Efficacy subscale of the Arthritis Self-Efficacy Scale was the dependent measure. Independent measures included age, education, scores from the Center for Epidemiologic Studies Depression and State-Trait Anxiety Inventory questionnaires, medial joint space and varus/valgus tibiofemoral angle from radiographs, body mass index, and isokinetic quadriceps and hamstrings strength. Knee pain and stiffness, assessed using the Western Ontario and McMaster Universities Osteoarthritis Index, were independent measures. RESULTS: Fifty-one percent of the variance of Functional Self Efficacy was explained by knee stiffness, hamstrings strength, age, and depression scores. Pain, education, anxiety, radiographic joint space, and body weight did not significantly contribute to the variance in Functional Self-Efficacy scores. Substituting quadriceps strength for hamstrings strength resulted in a regression model that included only stiffness, age, and depression, which explained nearly as much variance as the original model. CONCLUSION: Self efficacy for physical tasks is related to the sensation of stiffness, hamstrings strength, age, and level of depressive symptoms in persons with knee OA. Clinicians and researchers could consider these variables when assessing the level of self efficacy for physical tasks in persons with knee OA.

Activities of Daily Living↗

PubMed2006

A randomized controlled trial of supervised versus unsupervised exercise programs for ambulatory stroke survivors.

BACKGROUND AND PURPOSE: Little is known about the relative efficacy of supervised versus unsupervised community exercise programs for stroke survivors. This study compared the effectiveness of a 10-week supervised strengthening and conditioning program (supervised) with a 1-week supervised instruction program followed by a 9-week unsupervised home program (unsupervised) and evaluated retention of changes at 6 months and 1 year after program completion. METHODS: Seventy-two subjects retained at baseline (27 women, 45 men; mean+/-SD age, 64.6+/-11.8 years) were randomly allocated to receive the supervised or unsupervised program. The primary outcome was walking speed over 6 minutes, and secondary outcome measures were Human Activity Profile, Medical Outcome Study 36-Item Short-Form survey (SF-36), Physiological Cost Index, and lower extremity muscle strength. RESULTS: The 6-minute walking speed increased significantly in both groups and remained significantly improved by 1 year. The Human Activity Profile demonstrated an increasing trend only in the supervised group that was significant by 1 year. The SF-36 Physical Component summary score increased significantly in the supervised group and remained improved by 1 year; the unsupervised group showed significant improvement at 1 year. Women made greater gains in supervised programs, but men made greater gains in unsupervised programs. CONCLUSIONS: Supervised exercise programs and unsupervised programs after initial supervised instruction were both associated with physical benefits that were retained for 1 year, although supervised programs showed trends to greater improvements in self-reported gains. Gender differences require further research.

Activities of Daily Living↗

PubMed2006

Determinants of self-report outcome measures in people with knee osteoarthritis.

OBJECTIVES: To identify the determinants of self-report mobility measures in people with knee osteoarthritis (OA) and to compare self-report measures with physical performance. DESIGN: Cross-sectional, prospective. SETTING: Motor performance laboratory and human mobility research center. PARTICIPANTS: A convenient sample of 54 participants with medial compartment knee OA (32 women, 22 men; age 68.3+/-8.7y; range, 50-87y). Three participants were excluded because of the presence of lateral knee OA on radiographs. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Self-reports were recorded by using the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC) and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Performance measures included the six-minute walk test (6MWT), Timed Up & Go (TUG) test, and a standardized stair-climbing task (STR). RESULTS: Stepwise linear regression analysis identified models that included pain, quadriceps and hamstrings strength, and depression to explain 62% to 73% of the variance in scores on the physical functioning subscale of the WOMAC and the SF-36. These self-report measures had a moderate relation (r range, .46-.64) with performance measures (6MWT, TUG, STR). CONCLUSIONS: Self-report measures were strongly related to pain; physical performance measures were strongly related to self-efficacy. Regression models showed that self-report scores reflect pain, knee strength, and depression. The relation between self-report and performance measures was moderate, suggesting that these examine different aspects of mobility.

Activities of Daily Living↗

PubMed2006

Accuracy of clinical observations of push-off during gait after stroke.

OBJECTIVE: To determine the accuracy (criterion-related validity) of real-time clinical observations of push-off in gait after stroke. DESIGN: Criterion-related validity study of gait observations. SETTING: Rehabilitation hospital in Australia. PARTICIPANTS: Eleven participants with stroke and 8 treating physical therapists. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Pearson product-moment correlation between physical therapists' observations of push-off during gait and criterion measures of peak ankle power generation from a 3-dimensional motion analysis system. RESULTS: A high correlation was obtained between the observational ratings and the measurements of peak ankle power generation (Pearson r =.98). The standard error of estimation of ankle power generation was .32W/kg. CONCLUSIONS: Physical therapists can make accurate real-time clinical observations of push-off during gait following stroke.

Adult↗

PubMed2005

Contribution of psychosocial and mechanical variables to physical performance measures in knee osteoarthritis.

BACKGROUND AND PURPOSE: This cross-sectional study evaluated the relative contributions of psychosocial and mechanical variables to physical performance measures in people with knee osteoarthritis (OA). SUBJECTS: Fifty-four subjects (age, in years: mean=68.3, SD=8.7, range=50-87) with radiographically confirmed knee OA were included in this study. METHODS: Physical performance measures included the Six-Minute Walk Test (SMW), the Timed "Up & Go" Test (TUG), and a stair-climbing task (STR). Responses to psychosocial questionnaires that reflect depression, anxiety, and self-efficacy (a person's confidence in his or her ability to complete a task) were collected. Mechanical variables measured included body mass index and knee strength (force-generating capacity of muscle). Stepwise linear regressions were performed with the SMW, TUG, and STR as separate dependent variables. RESULTS: Functional self-efficacy explained the greatest amount of variance in all performance measures, contributing 45% or more. Knee strength and body weight also explained some variance in performance measures. Anxiety and depression did not explain any variance in performance. DISCUSSION AND CONCLUSION: Physical therapists evaluating the significance of the SMW, TUG, and STR scores in subjects with knee OA should note that a large part of each score reflects self-efficacy, or confidence, for physical tasks, with some contributions from knee strength and body weight.

Aged↗

PubMed2003

Accuracy and reliability of observational gait analysis data: judgments of push-off in gait after stroke.

BACKGROUND AND PURPOSE: Physical therapists routinely observe gait in clinical practice. The purpose of this study was to determine the accuracy and reliability of observational assessments of push-off in gait after stroke. SUBJECTS: Eighteen physical therapists and 11 subjects with hemiplegia following a stroke participated in the study. METHODS: Measurements of ankle power generation were obtained from subjects following stroke using a gait analysis system. Concurrent videotaped gait performances were observed by the physical therapists on 2 occasions. Ankle power generation at push-off was scored as either normal or abnormal using two 11-point rating scales. These observational ratings were correlated with the measurements of peak ankle power generation. RESULTS: A high correlation was obtained between the observational ratings and the measurements of ankle power generation (mean Pearson r=.84). Interobserver reliability was moderately high (mean intraclass correlation coefficient [ICC (2,1)]=.76). Intraobserver reliability also was high, with a mean ICC (2,1) of.89 obtained. DISCUSSION AND CONCLUSION: Physical therapists were able to make accurate and reliable judgments of push-off in videotaped gait of subjects following stroke using observational assessment. Further research is indicated to explore the accuracy and reliability of data obtained with observational gait analysis as it occurs in clinical practice.

Adult↗