Gail L. Widener

Effect of an equine-movement therapy program on gait, energy expenditure, and motor function in children with spastic cerebral palsy: a pilot study

The purpose of this study was to evaluate the effects of an 8‐week program of hippotherapy on energy expenditure during walking; on the gait dimensions of stride length, velocity, and cadence; and on performance on the Gross Motor Function Measure (GMFM) in five children with spastic cerebral palsy (CP). A repeated‐measures within‐subjects design was used consisting of two baseline measurements taken 8 weeks apart, followed by an 8‐week intervention period, then a posttest. After hippotherapy, all five children showed a significant decrease (Xr2;=7.6, P<0.05) in energy expenditure during walking and a significant increase (Xr2=7.6, P<0.05) in scores on Dimension E (Walking, Running, and Jumping) of the GMFM. A trend toward increased stride length and decreased cadence was observed. This study suggests that hippotherapy may improve energy expenditure during walking and gross motor function in children with CP.

Randomized Clinical Trial of Balance-Based Torso Weighting for Improving Upright Mobility in People with Multiple Sclerosis

Background. Torso weighting has sometimes been effective for improving upright mobility in people with multiple sclerosis, but parameters for weighting have been inconsistent. Objective. To determine whether balance-based torso weighting (BBTW) has immediate effects on upright mobility in people with multiple sclerosis. Methods. This was a 2-phase randomized clinical trial. In phase 1, 36 participants were randomly assigned to experimental and control groups. In phase 2, the control group was subsequently randomized into 2 groups with alternate weight-placement. Tests of upright mobility included: timed up and go (TUG), sharpened Romberg, 360-degree turns, 25-foot walk, and computerized platform posturography. Participants were tested at baseline and again with weights placed according to group membership. In both phases, a physical therapist assessed balance for the BBTW group and then placed weights to decrease balance loss. In phase 1, the control group had no weights placed. In phase 2, the alternate treatment group received standard weight placement of 1.5% body weight. Results. People with BBTW showed a significant improvement in the 25-foot walk (P = .01) over those with no weight, and the TUG (P = .01) over those with standard weight placement. BBTW participants received an average of 0.5 kg, less than 1.5% of any participant’s body weight. Conclusion. BBTW can have immediate advantages over a nonweighted condition for gait velocity and over a standardized weighted condition for a functional activity in people with multiple sclerosis (MS) who are ambulatory but have balance and mobility abnormalities.

Balance-Based Torso-Weighting May Enhance Balance in Persons With Multiple Sclerosis: Preliminary Evidence

OBJECTIVE To determine whether weight placed on the trunk in response to directional balance loss would enhance function and stability in people with multiple sclerosis (MS). DESIGN Quasi-experimental study in which subjects served as their own controls. SETTING Research laboratory. PARTICIPANTS Subjects (N=16) age 20 to 65 years with MS recruited through the Northern California Chapter of the National Multiple Sclerosis Society. INTERVENTIONS Balance-based torso-weighting where up to 1.5% body weight was placed in a garment on the trunk. Subjects were tested at baseline and then in randomly ordered balance-based torso-weighting and nonweighted garment conditions. MAIN OUTCOME MEASURES Sharpened Romberg, eyes open (SREO) and Sharpened Romberg, eyes closed, computerized dynamic platform posturography (CDPP), Timed Up & Go (TUG), and 25-foot timed walk. RESULTS Significant improvement (P<.014) was found with SREO in the balance-based torso-weighting compared with nonweighted conditions. CDPP eyes open and TUG showed improvements (P<.03) from baseline to balance-based torso-weighting and nonweighted conditions. CONCLUSIONS Improved performance in a group of adults with MS was seen when light weights were placed on the torso to counteract balance loss. Placement of weights may have the potential to produce immediate improvements in balance in this population.

Outcome Measures for Individuals With Multiple Sclerosis: Recommendations From the American Physical Therapy Association Neurology Section Task Force

Various studies have described the benefits of using outcome measures (OMs) in physical therapist practice1–3; however, multiple barriers interfere with their use (eTab. 1).1,3,4 Most notably, a limited understanding of how to select and apply the best OM has been reported to be a barrier.3,4 Wedge et al3 reported that physical therapists do not always critically evaluate the psychometric properties of OMs, are unfamiliar with OM-related resources, and have difficulties determining patient suitability for particular OMs. Physical therapists working with people with multiple sclerosis (MS) have additional challenges when selecting OMs. Multiple sclerosis is a complex, heterogeneous, and progressive disorder causing a wide variety of symptoms among patients.5,6 Symptom variability in individual patients throughout the course of the disease also must be considered. Additionally, people with MS are treated in a variety of settings, which may affect OM selection and use (eg, due to limited space and equipment in a home environment). Thus, selecting 1 or 2 OMs for use with all people with MS is challenging, requiring the clinician to determine the most appropriate OMs to measure relevant constructs. Although some resources exist to assist the physical therapist with identifying and selecting OMs for people with MS,7–13 literature is lacking that describes a consensus-based method to determine which OMs are appropriate for people with MS at various disability levels and in different practice settings. In 2009, the American Physical Therapy Association (APTA) Neurology Section (“the Section”) began a process to develop recommendations for the use of OMs for patients with neurological conditions, beginning with stroke (information pertaining to the Sections OM recommendations is available elsewhere14). The following year, the Section expanded its efforts by creating a task force …

Gait changes with balance-based torso-weighting in people with multiple sclerosis.

BACKGROUND AND PURPOSE People with multiple sclerosis (PwMS) commonly have mobility impairments that may lead to falls and limitations in activities. Physiotherapy interventions that might improve mobility typically take several weeks. Balance-based torso-weighting (BBTW), a system of strategically placing light weights to improve response to balance perturbations, has resulted in immediate small improvements in clinical measures in PwMS, but changes in spatiotemporal gait parameters are unknown. The purpose was to investigate the effects of BBTW on gait parameters in PwMS and healthy controls. METHODS DESIGN This study is a non-randomized controlled experiment. PARTICIPANTS This study included 20 PwMS and 20 matched healthy controls PROCEDURES People with multiple sclerosis walked on an instrumented mat at their fastest speed for three trials each in two conditions: without BBTW then with BBTW. Healthy controls walked in both conditions at two speeds: their fastest speed and at velocities equivalent to their matched PwMS. RESULTS Averaged gait trials showed that, with BBTW, PwMS had significantly increased velocity (p = 0.002), cadence (p = 0.007) and time spent in single-limb support (p = 0.014), with decreased time in double-limb support (p = 0.004). Healthy controls increased velocity (p = 0.012) and cadence (p = 0.015) and decreased support base (p = 0.014) in fast trials with BBTW; at matched velocities, step length (p = 0.028) and support base (p = 0.006) were significantly different from PwMS. All gait variables in healthy controls at fast speeds were significantly different from PwMS walking at their fastest speeds. DISCUSSION All participants showed increases in gait velocity and cadence during fast walk with BBTW. Improvements in time spent in single-limb and double-limb support by PwMS with BBTW may reflect greater stability in gait. Future research might ascertain if these immediate improvements could enhance effectiveness of longer-term physiotherapy on functional mobility in PwMS.

Selecting Rehabilitation Outcome Measures for People with Multiple Sclerosis

Despite the well-known benefits of using standardized outcome measures (OMs) in clinical practice, a variety of barriers interfere with their use. In particular, rehabilitation therapists lack sufficient knowledge in selecting appropriate OMs. The challenge is compounded when working with people with multiple sclerosis (MS) owing to heterogeneity of the patient population and symptom variability in individual patients. To help overcome these barriers, the American Physical Therapy Association appointed the Multiple Sclerosis Outcome Measures Task Force to review and make evidence-based recommendations for OM use in clinical practice, education, and research specific to people with MS. Sixty-three OMs were reviewed based on their clinical utility, psychometric properties, and a consensus evaluation of the appropriateness of use for people with MS. We sought to illustrate use of the recommendations for two cases. The first case involves a 43-year-old man with new-onset problems after an exacerbation. The second case pertains to an outpatient clinic interested in assessing the effectiveness of their MS rehabilitation program. For each case, clinicians identified areas that were important to assess and various factors deemed important for OM selection. Criteria were established and used to assist in OM selection. In both cases, the described processes narrowed the selection of OMs and assisted with choosing the most appropriate ones. The recommendations, in addition to the processes described in these two cases, can be used by clinicians in any setting working with patients with MS across the disability spectrum.

Variability in Postural Control With and Without Balance-Based Torso- Weighting in People With Multiple Sclerosis and Healthy Controls

Background People with multiple sclerosis (MS) have diminished postural control, and center of pressure (COP) displacement varies more in this population than in healthy controls. Balance-based torso-weighting (BBTW) can improve clinical balance and mobility in people with MS, and exploration using both linear and nonlinear measures of COP may help determine whether BBTW optimizes movement variability. Objective The aim of this study was to investigate the effects of BBTW on people with MS and healthy controls during quiet standing. Design This was a quasi-experimental study comparing COP variability between groups, between eye closure conditions, and between weighting conditions in the anterior-posterior and medial-lateral directions. Methods Twenty participants with MS and 18 healthy controls stood on a forceplate in 4 conditions: eyes open and closed and with and without BBTW. Linear measures of COP displacement included range and root mean square (RMS). Nonlinear measures included approximate entropy (ApEn) and Lyapunov exponent (LyE). Three-way repeated-measures analyses of variance compared measures across groups and conditions. The association between weighting response and baseline nonlinear variables was examined. When significant associations were found, MS subgroups were created and compared. Results The MS and control groups had significantly different range, RMS, and ApEn values. The eyes-open and eyes-closed conditions had significantly different range and RMS values. Change with weighting correlated with LyE (r=−.70) and ApEn (r=−.59). Two MS subgroups, with low and high baseline LyE values, responded to BBTW in opposite directions, with a significant main effect for weighting condition for the LyE variable in the medial-lateral direction. Limitations The small samples and no identification of impairments related to LyE at baseline were limitations of the study. Conclusions The LyE may help differentiate subgroups who respond differently to BBTW. In both subgroups, LyE values moved toward the average of healthy controls, suggesting that BBTW may help optimize movement variability in people with MS.

Renal compensation of hypercapnia in prolonged hypoxia

We previously showed that rats made hypoxic for three weeks were able to regulate their plasma pH better than normoxic rats during acute hypercapnia. This improved pH regulation was abolished by nephrectomy, suggesting that it was due, at least in part, to a more effective renal compensation of hypercapnia in hypoxic rats. To test this possibility renal acid excretion was measured in conscious rats that had been kept at PB 370-380 Torr for three weeks. The rats were studied in a chamber where PIO2 was kept at 68-70 Torr at ambient PB (740-750 Torr). Controls were pair-fed normoxic rats. After a 2 h control period, inspired PCO2 was increased for 4 h. The apparent non-bicarbonate buffer value of arterial blood plasma was twice as high in the hypoxic than in the normoxic rats. Renal excretion of ammonium increased to a similar extent during hypercapnia in both normoxic and hypoxic rats. Titratable acid excretion of normoxic rats did not change significantly during hypercapnia. In the hypoxic rats, on the other hand, total excretion of titratable acid in the 2 h control period was 90.9 +/- 16.4 mumol/rat; and increased to 150.0 +/- 13.4 mumol/rat in the first 2 h and to 232.9 +/- 26.0 mumol/rat in the last 2 h of hypercapnia. In spite of this large increase in acid excretion, urine pH of hypoxic rats did not change significantly, indicating a higher buffer value of the urine of hypoxic rats. These results confirm our previous observations and support the idea that the improved pH regulation of hypoxic rats is due in part to a more effective renal compensation of hypercapnia.

Effects of Torso-Weighting on Standing Balance and Falls During the Sensory Organization Test in People with Multiple Sclerosis

Background In people with multiple sclerosis (MS), common gait and balance impairments can lead to falls, fear of falling, activity restriction, and social isolation. Sensory augmentation in the form of torso-weighting has resulted in improvement in gait and balance, but research on its effect on falls in MS is lacking. Methods 60 people with MS and 10 bin-matched controls completed the Sensory Organization Test (SOT) while nonweighted and again while weighted using the Balance-Based Torso-Weighting assessment method. This was a quasi-experimental pre-post intervention study. The SOT composite scores, equilibrium scores, and number of falls occurring across six SOT conditions were compared between and within groups using 2-way analysis of variance, α = .05 with planned t test analyses of weighting effects. Results A significant increase in composite score of 9.14 points nonweighted to weighted occurred in the MS group (P < .001) but not in controls (P = .626). Equilibrium scores were significantly higher with weights in the MS group (P < .001) but not in controls (P = .5). Falls during the SOT were reduced by 35% with weights in the MS group versus without weights (P < .001), with the greatest number of falls occurring in the most challenging SOT conditions. Conclusions During a single testing session, torso-weighting produced significant improvements in postural stability and fall reduction during the SOT for people with MS but no change in controls. Further research is needed to determine whether torso-weighting has the potential to reduce falls in MS during real-world activities.

Regulation of the Acid-Base Balance During Prolonged Hypoxia: Effects of Respiratory and Non-Respiratory Acidosis

Prolonged hypoxia results in adaptive changes in the oxygen transfer system which appear to be designed to insure adequate oxygen supply to the cells (for review, see Bouverot, 1985). Many of these adaptations, however, produce other functional changes not directly concerned with oxygen transfer. Examples of this are the acid-base changes of high altitude hypoxia. Fig. 1 shows the time course of changes in plasma acid-base balance in male conscious rats exposed to a barometric pressure of 370-380 torr (Gonzalez and Clancy, 1986a). The hyperventilation initially results in respiratory alkalosis; this is eventually corrected by a proportionate decrease in plasma [HCO 3 - ], which is largely due, in turn, to the renal compensatory mechanisms put into motion by the alkalosis. After three weeks of hypoxia, plasma pH has returned to normal, but at the expense of depletion of HCO 3 - .