Elizabeth J. Protas

Effects of visual and auditory cues on gait in individuals with Parkinson's disease

The purpose of this study was to determine if combining visual and auditory cues has a greater effect on the gait pattern of patients with Parkinsons disease (PD) than the cues applied individually. Twenty-four individuals with idiopathic PD were recruited. Patients, while off antiparkinsonian medications, were measured on a 7.62-m walkway during two trials for each of four conditions performed in random order: without cues, with a visual cue, with an auditory cue and with both cues simultaneously. The auditory cue consisted of a metronome beat 25% faster than the subjects fastest gait speed. Brightly colored parallel lines placed along the walkway at intervals equal to 40% of a subjects height served as the visual cue. Average gait speed, cadence and stride length were calculated for each condition. Gait velocity, cadence and stride length significantly improved (p<005) when cues were used. Visual and auditory cues improved gait performance in patients with PD, but they did so in different ways. Auditory cueing significantly improved cadence, but visual cueing improved stride length. The simultaneous use of auditory and visual cues did not improve gait significantly more than each cue alone.

Performance-based gait tests for acute stroke patients

OBJECTIVE Qualitative measures may not differentiate severity of deficits after an acute or subacute stroke. The aim of this study was to contrast the utility of performance-based gait tests with qualitative measures in a sample of acute stroke patients. DESIGN Twenty acute stroke subjects had their performance-based gait measured by gait speed, walking distance, gait energy expenditure, and gait energy cost. They were also qualitatively evaluated for cognition, functional outcomes, motor impairment, and Functional Ambulation Category. RESULTS Strong and significant correlations were observed among performance-based gait tests. Qualitative scales indicated moderate to minimal deficits in each domain evaluated, although they were not correlated among themselves, except for Functional Ambulation Category and FIM and FIM and Mini-Mental State Exam. Functional Ambulation Category correlated with performance-based gait tests. CONCLUSIONS Performance-based gait tests are feasible to conduct during early recovery after a stroke and allow better discrimination among the patients than qualitative measures.

Ambulatory Activity of Older Adults Hospitalized with Acute Medical Illness

OBJECTIVES: To describe the amount and patterns of ambulatory activity in hospitalized older adults over consecutive hospital days.

Exercise performance in those having Parkinson's disease and healthy normals

OBJECTIVE This study assessed and compared the cardiopulmonary function of individuals with Parkinsons disease (PD) with that of healthy normals (HN) in order to provide health professionals with more thorough information about the problems associated with PD. METHODS 20 men (PD = 13, HN = 7; mean age 64 and 64, respectively) and 23 women (PD = 7, HN = 16; mean age 65 and 66, respectively) were recruited from the Houston metropolitan area. Maximal oxygen consumption (VO2max mL x kg(-1) x min(-1)) and time to maximal exercise in minutes (time(max)) were measured. Exercise was performed on a stationary bicycle using an incremental exercise protocol. Because the assumption of homogeneity of variance was not met for the dependent variable VO2max in women, the nonparametric Wilcoxon-Mann-Whitney-U analysis was used (alpha < or = 0.025). All other group comparisons were analyzed using an independent t-test (alpha < or = 0.025). RESULTS For men and women, there were no significant differences in VO2max between those having PD and the HN (men: PD = 23.52 vs HN = 25.46 mL x kg(-1) x min(-1), P = 0.50; women: PD = 20.10 vs HN = 16.20 mL x kg(-1) x min(-1), P = 0.35). Likewise, there was no significant differences in time(max) between women (PD = 5.2 vs HN = 5.4 min, P = 0.20). Comparison of time(max) between men did show a significant difference (PD = 9.5 vs HN = 13.10 min, P = 0.02). CONCLUSIONS Although there were no significant differences in VO2max between the men, the comparison of time(max) indicates those with PD were unable to exercise as long before reaching VO2max, indicating that individuals with PD may be less efficient during exercise and therefore unable to exercise as long before reaching VO2max. Although women with PD had a higher VO2max, comparisons of VO2max and time(max) between those with PD and HN resulted in no significant differences.

Reliability of measures of gait performance and oxygen consumption with stroke survivors.

The measurement of physical activity, especially walking activity, is important for many outcome studies. In many investigations, the Physical Activity scale of the short-form-36 (SF-36) health assessment questionnaire is used in lieu of an actual physical measurement of walking. This study determined the relationship between the SF-36 questionnaire and the Step Activity Monitor (SAM), a real-world performance-based tool that counts the actual number of steps taken during daily activities. We studied the physical activity of 57 men with diabetes using step count monitoring and the SF-36 questionnaire. The subjects averaged 3,293 steps/day, but had a very wide range (111-11,654) and a large standard deviation (SD = 2,037). The correlations between total daily steps and the SF-36 Physical Component Summary score, and the Physical Function, Bodily Pain, and Vitality scales of the SF-36 were only fair (Pearsons r = 0.376, 0.488, 0.332, 0.380, respectively). The corresponding coefficients of determination range from only 7.7% to 23.8%. Physical activity is a complex concept not completely represented by either the SF-36 or the step counts. The correlation between actual walking activity and the SF-36 is not as strong as many researchers believe. Caution should be exercised with the use of the SF-36 to specifically measure walking activity.This study assessed the reliability of gait performance with concurrent measures of oxygen consumption (VO2) in stroke survivors (SS). Nine male SS (60.00 +/- 15.08 yr) had a recent history of stroke (44.56 +/- 51.35 days since the stroke) and were receiving rehabilitation. Four had a right cerebrovascular accident (CVA), and five had a left CVA. Subjects walked without assistance, although three used a single cane to complete the test. Within 30 minutes, subjects completed two trials of a 5 min walk while walking back and forth on a 5 m walkway wearing a portable gas analyzer to collect samples of gases. The intraclass correlation coefficient (ICC) was used to assess reliability. The ICC for gait energy expenditure, walk distance, gait speed, and gait energy cost were 0.64, 0.97, 0.95, and 0.97, respectively. Assessment of gait performance with concurrent measures of VO2 is a reliable procedure with SS.

Differential responses to measures of gait performance among healthy and neurologically impaired individuals

OBJECTIVES To compare gait during a 5-minute walk among healthy individuals, persons with spinal cord injury (SCI), and stroke survivors and to investigate whether simultaneous measures of oxygen consumption enhance information about performance. DESIGN Descriptive study. SETTING Veterans Affairs medical center. PARTICIPANTS Thirty-nine healthy individuals, 10 persons with SCI, and 20 stroke survivors. INTERVENTIONS Participants were fitted with a portable gas analyzer and walked on a 5-m walkway for 5 minutes. MAIN OUTCOME MEASURES Measures of walk distance, gait speed, gait energy expenditure (GEE), and gait cost were obtained, along with measures of ventilation (.Ve), ventilation and carbon dioxide production slope (.Ve . .VCo2), oxygen pulse, and heart rate. RESULTS The SCI group (127.65+/-81.74m) walked less than the stroke survivors (148.80+/-64.3m) or the healthy group (268.90+/-35.01m) but had higher energy demands, as shown by GEE (SCI group, 13.28+/-3.23mL.kg(-1).min(-1); stroke group, 10.18+/-2.14mL.kg(-1).min(-1); healthy group, 9.61+/-1.90mL.kg(-1).min(-1)) and by gait cost (SCI group,.57+/-.40 mL.kg(-1).m(-1); stroke group,.40+/-.52mL.kg(-1).m(-1); healthy group,.18+/-.02mL.kg(-1).m(-1)). Compared with the healthy group, the stroke group had higher .Ve (stroke group, 22.34+/-5.20L/min vs healthy group, 16.11+/-3.22L/min) and .Ve . .VCo2 slope (24.22+/-8.80 vs 18.73+/-5.44, respectively). CONCLUSION Use of metabolic assessment during the 5-minute walk was feasible and provided further information for evaluating gait performance with the subjects studied.

Back Pain, Physical Function, and Estimates of Aerobic Capacity: What Are the Relationships Among Methods and Measures?

Cunha IT, Simmonds MJ, Protas EJ, Jones S: Back pain, physical function, and estimates of aerobic capacity: What are the relationships among methods and measures? Am J Phys Med Rehabil 2002;81:913–920. Objectives To establish the correlations of measures of self-reported disability, self-efficacy, physical performance, level of pain, and estimates of aerobic capacity (Pvo2) in subjects with low back pain. Design Fifty-one low back pain subjects, ranging in age from 26 to 65 yr, entered the study. Participants completed the Roland-Morris Disability Questionnaire and the self-efficacy questionnaire. Physical performance was evaluated by the loaded-reach test, sit/stand test, 5-min walk test, 50-foot walking test, and time to roll from right to left. Pain intensity and pain affect were measured using two visual analog scales. Pvo2 was predicted from an equation. Results The correlation coefficient among the physical performance outcomes ranged from 0.47 to 0.78. Pain measures had low correlations with measures of function but stronger correlations with other self-report measures. The disability measure correlated moderately with physical performance. Correlations between Pvo2 and all other measurements were minimal, except for the 5-min walk test. Conclusion Performance and disability were more consistent in evaluating low back pain. Pvo2 failed to correlate with most other aspects of low back pain. This study suggests that aerobic capacity might not be a primary concern for patients with low back pain.

Gait variability in Parkinson’s disease: influence of walking speed and dopaminergic treatment

Abstract Objectives: To study the effects of levodopa and walking speed on gait variability in individuals with Parkinson’s disease (PD). Methods: Thirty-three individuals with PD were studied. Their mean age was 70·61±9·23 year. The average time since diagnosis was 9·65±5·80 year. Gait variability was studied while ‘OFF’ and ‘ON’ dopaminergic medication when the subjects walked at their usual and fastest speeds. Results: Variability of step time, double support time, stride length and stride velocity decreased significantly (P=0·037; P=0·037; P=0·022; P=0·043, respectively) after dopaminergic treatment. When subjects increased walking speed, the variability of stride length and stride velocity decreased significantly (P=0·038 and P=0·004, respectively) both while ‘OFF’ and ‘ON’ levodopa. Increasing walking speed did not change the variability of step time and double support time regardless of medication status. Conclusions: Levodopa decreased gait variability in persons with PD. Stride length and stride velocity variability appeared to be speed dependent parameters, whereas, the variability of step time and double support time appeared to be speed independent measures. Levodopa had positive effects on gait stability in PD.

Relationship of Falls and Fear of Falling to Activity Limitations and Physical Inactivity in Parkinson’s Disease

AIM To investigate the relationships between falls, fear of falling, and activity limitations in individuals with Parkinsons disease (PD). DESIGN/METHODS Cross-sectional study of individuals with mild to moderate PD (N = 83). Associations among demographic data, fall frequency, disease severity, motor impairment, ability to perform activities of daily living (ADL), Activities Balance Confidence Scale, Iowa Fatigue Scale, Comorbidity Index, and Physical Activity Scale for Elders were studied. RESULTS Frequent fallers had more ADL limitations than nonfallers (p < .001) and rare fallers (p = .004). Frequent fallers reported a lower percentage of ability to perform ADL than nonfallers (p = .003). Frequent fallers and rare fallers were less physically active than nonfallers (p = .015 and p = .040, respectively). Frequent fallers and rare fallers reported a higher level of fear of falling than nonfallers (p = .031 and p = .009, respectively). CONCLUSIONS Falls and fear of falling were associated with more ADL limitations and less physical activity after adjusting for physical impairments.

Influence of fear of falling on gait and balance in Parkinson’s disease

Abstract Purpose: To study the relationship of fear of falling (FoF) with gait characteristics and balance in individuals with Parkinsons disease (PD). Method: Seventy-nine non-demented individuals (62 males) with PD were studied. Their mean age was 69.22 ± 8.93 years. The average time since diagnosis was 8.27 ± 5.31 years. FoF was assessed by the Activities-specific Balance Confidence (ABC) Scale in which high scores indicate less FoF. Gait was measured using a computerized walkway. Balance was measured by timed tests including the 5-step test, 360 degree turn, timed sideways walk, and timed up and go test. Participants were divided into two groups based on their ABC score (high FoF, ABC score <69; low FoF, ABC score ≥69). Gait characteristics and balance measures of the two groups were compared. Results: Gait speed and stride length for forward walking (p < 0.0005 for both) and backward walking (p = 0.001 and 0.002, respectively) were lower for those with a high level of FoF compared to those with a low level of FoF. The time to take five steps (p = 0.025), time to turn (p < 0.0005), time to walk sideways (p = 0.001), and time to complete the up and go test (p = 0.003) were longer in those with a high level of FoF than in those with a low level of FoF. Number of steps to complete the turn (p = 0.001) and steps to walk sideways (p = 0.002) were greater in those with a high level of FoF than in those with a low level FoF. Conclusions: Gait and balance of individuals with PD with a high level of FoF were poorer than those with a low level of FoF, regardless of previous fall history. Implications for Rehabilitation The results demonstrates that fear of falling (FoF) is related to gait and balance in individuals with PD. Clinicians should be aware that FoF has a negative impact on gait and balance in individuals with PD.