Modeling Cues May Reduce Sway Following Sit-To-Stand Transfer for People with Parkinson's Disease.

Cues are commonly used to overcome the effects of motor symptoms associated with Parkinson's disease. Little is known about the impact of cues on postural sway during transfers. The objective of this study was to identify if three different types of explicit cues provided during transfers of people with Parkinson's disease results in postural sway more similar to healthy controls. This crossover study had 13 subjects in both the Parkinson's and healthy control groups. All subjects completed three trials of uncued sit to stand transfers. The Parkinson's group additionally completed three trials of sit to stand transfers in three conditions: external attentional focus of reaching to targets, external attentional focus of concurrent modeling, and explicit cue for internal attentional focus. Body worn sensors collected sway data, which was compared between groups with Mann Whitney U tests and between conditions with Friedman's Tests. Sway normalized with modeling but was unchanged in the other conditions. Losses of balance presented with reaching towards targets and cueing for an internal attentional focus. Modeling during sit to stand of people with Parkinson's disease may safely reduce sway more than other common cues.

Turning Toward Monitoring of Gaze Stability Exercises: The Utility of Wearable Sensors.

BACKGROUND AND PURPOSE: Few tools are currently available to quantify gaze stability retraining exercises. This project examined the utility of a head-worn inertial measurement unit (IMU) to quantify head movement frequency, velocity, and amplitude during gaze stability exercises. METHODS: Twenty-eight individuals with multiple sclerosis and complaints of dizziness or a history of falls were randomly assigned to either a strength and aerobic exercise (SAE) or gaze and postural stability (GPS) group. During a 6-week intervention, participants wore a head-mounted IMU 3 times (early, middle, and late). For aim 1, the frequency, mean peak velocity, and mean peak amplitude of head turns during equivalent duration components of group-specific exercises were compared using general linear models. For aim 2, the progression of treatment in the GPS group was examined using general linear regression models for each outcome. RESULTS: Aim 1 revealed the GPS group demonstrated significantly greater velocity and amplitude head turns during treatment than the SAE group. The frequency of head turns did not significantly differ between the 2 groups. The aim 2 analyses demonstrated that the yaw and pitch frequency of head turns significantly increased during gaze stability exercises over the 6-week intervention. Velocity and amplitude of head turns during yaw and pitch gaze stability exercises did not significantly change. DISCUSSION AND CONCLUSIONS: A head-worn IMU during rehabilitation distinguished between groups. Furthermore, within the GPS group, the IMU quantified the progression of the frequency of head movements during gaze stability exercises over time.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A320).

Rehabilitation to improve gaze and postural stability in people with multiple sclerosis: study protocol for a prospective randomized clinical trial.

BACKGROUND: The use of vestibular rehabilitation principles in the management of gaze and postural stability impairments in people with multiple sclerosis (PwMS) has shown promise in pilot work completed in our lab and in a recently published randomized clinical trial (RCT). However, further work is needed to fully quantify the gaze and postural impairments present in people with multiple sclerosis and how they respond to rehabilitation. METHODS/DESIGN: The study is a single blind RCT designed to examine the benefit of a gaze and postural stability (GPS) intervention program compared to a standard of care (SOC) rehabilitation program in dizzy and balance impaired PwMS. Outcomes will be collected across the domains of body structure and function, activity, and participation as classified by the World Health Organization International Classification of Functioning, Disability, and Health (ICF). Our primary outcomes are the Dizziness Handicap Inventory (DHI) and the Functional Gait Assessment (FGA). Secondary outcomes include other measures of gaze and postural stability, fatigue, and functional mobility. Participants who are interested and eligible for enrollment will be consented prior to completing a baseline assessment. Following the baseline assessment each participant will be randomized to either the GPS or SOC intervention group and will complete a 6 week treatment period. During the treatment period, both groups will participate in guided exercise 3x/week. Following the treatment period participants will be asked to return for a post-treatment evaluation and again for a follow-up assessment 1 month later. We anticipate enrolling 50 participants. DISCUSSION: This study will be an innovative RCT that will utilize gaze and postural stability metrics to assess the efficacy of vestibular rehabilitation in PwMS. It will build on previous work by examining measures across the ICF and improve the current evidence base for treating PwMS. TRIAL REGISTRATION: ClinicalTrials.gov, May 29th 2018, NCT03521557 .

Measurement instruments to assess posture, gait, and balance in Parkinson's disease: Critique and recommendations.

BACKGROUND: Disorders of posture, gait, and balance in Parkinson's disease (PD) are common and debilitating. This MDS-commissioned task force assessed clinimetric properties of existing rating scales, questionnaires, and timed tests that assess these features in PD. METHODS: A literature review was conducted. Identified instruments were evaluated systematically and classified as "recommended," "suggested," or "listed." Inclusion of rating scales was restricted to those that could be used readily in clinical research and practice. RESULTS: One rating scale was classified as "recommended" (UPDRS-derived Postural Instability and Gait Difficulty score) and 2 as "suggested" (Tinetti Balance Scale, Rating Scale for Gait Evaluation). Three scales requiring equipment (Berg Balance Scale, Mini-BESTest, Dynamic Gait Index) also fulfilled criteria for "recommended" and 2 for "suggested" (FOG score, Gait and Balance Scale). Four questionnaires were "recommended" (Freezing of Gait Questionnaire, Activities-specific Balance Confidence Scale, Falls Efficacy Scale, Survey of Activities, and Fear of Falling in the Elderly-Modified). Four tests were classified as "recommended" (6-minute and 10-m walk tests, Timed Up-and-Go, Functional Reach). CONCLUSION: We identified several questionnaires that adequately assess freezing of gait and balance confidence in PD and a number of useful clinical tests. However, most clinical rating scales for gait, balance, and posture perform suboptimally or have been evaluated insufficiently. No instrument comprehensively and separately evaluates all relevant PD-specific gait characteristics with good clinimetric properties, and none provides separate balance and gait scores with adequate content validity for PD. We therefore recommend the development of such a PD-specific, easily administered, comprehensive gait and balance scale that separately assesses all relevant constructs. © 2016 International Parkinson and Movement Disorder Society.

Effects of practice on variability of muscle force.

The motor skill required to decrease the variability in muscle force steadiness can be challenging. The purposes of this study were to determine whether muscle force steadiness improved following repeated trials and whether the number of trials varied for healthy younger adults, healthy older adults, and older adults who have fallen to obtain stable muscle force steadiness measures. Sixty participants performed 30 concentric and eccentric contractions of the knee extensors on an isokinetic dynamometer. Each group had significant improvements in muscle force steadiness and obtained stable measures within six to nine trials. Healthy younger and older adults, and older adults who have fallen, can improve muscle force steadiness. These findings provide a framework for methodological approaches when testing steadiness in varying populations.

Sensory Phenotypes for Balance Dysfunction After Mild Traumatic Brain Injury.

BACKGROUND AND OBJECTIVES: Recent team-based models of care use symptom subtypes to guide treatments for individuals with chronic effects of mild traumatic brain injury (mTBI). However, these subtypes, or phenotypes, may be too broad, particularly for balance (e.g., 'vestibular subtype'). To gain insight into mTBI-related imbalance we 1) explored whether a dominant sensory phenotype (e.g., vestibular impaired) exists in the chronic mTBI population, 2) determined the clinical characteristics, symptomatic clusters, functional measures, and injury mechanisms that associate with sensory phenotypes for balance control in this population, and 3) compared the presentations of sensory phenotypes between individuals with and without previous mTBI. METHODS: A secondary analysis was conducted on the Long-Term Impact of Military-Relevant Brain Injury Consortium - Chronic Effects of Neurotrauma Consortium. Sensory ratios were calculated from the Sensory Organization Test, and individuals were categorized into one of eight possible sensory phenotypes. Demographic, clinical, and injury characteristics were compared across phenotypes. Symptoms, cognition, and physical function were compared across phenotypes, groups, and their interaction. RESULTS: Data from 758 Service Members and Veterans with mTBI and 172 with no lifetime history of mTBI were included. Abnormal visual, vestibular, and proprioception ratios were observed in 29%, 36%, and 38% of people with mTBI, respectively, with 32% exhibiting more than one abnormal sensory ratio. Within the mTBI group, global outcomes (p<0.001), self-reported symptom severity (p<0.027), and nearly all physical and cognitive functioning tests (p<0.027) differed across sensory phenotypes. Individuals with mTBI generally reported worse symptoms than their non-mTBI counterparts within the same phenotype (p=0.026), but participants with mTBI in the Vestibular-Deficient phenotype reported lower symptom burdens than their non-mTBI counterparts [e.g., mean(SD) Dizziness Handicap Inventory = 4.9(8.1) for mTBI vs. 12.8(12.4) for non-mTBI, group*phenotype interaction p<0.001]. Physical and cognitive functioning did not differ between groups after accounting for phenotype. DISCUSSION: Individuals with mTBI exhibit a variety of chronic balance deficits involving heterogeneous sensory integration problems. While imbalance when relying on vestibular information is common, it is inaccurate to label all mTBI-related balance dysfunction under the 'vestibular' umbrella. Future work should consider specific classification of balance deficits, including specific sensory phenotypes for balance control.

The 9-hole PEG test of upper extremity function: average values, test-retest reliability, and factors contributing to performance in people with Parkinson disease.

BACKGROUND AND PURPOSE: Pegboard tests of hand dexterity are commonly used in clinical settings to assess upper extremity function in various populations. For individuals with Parkinson disease (PD), the clinical utility of pegboard tests has not been fully evaluated. Our purpose was to examine the commercially available 9-Hole Peg Test (9HPT) using a large sample of individuals with PD to determine average values, test-retest reliability, and factors predictive of 9HPT performance. METHODS: A total of 262 participants with PD (67% men, Hoehn & Yahr stage = 2.3 ± 0.7) completed the 9HPT along with a battery of other tests including the Movement Disorder Society Unified PD Rating Scale-Motor Subscale III and Freezing of Gait Questionnaire. RESULTS: Average time to complete the 9HPT was 31.4 ± 15.7 s with the dominant and 32.2 ± 12.4 s with the nondominant hand. Test-retest reliability of 2 trials performed with the same hand was high (dominant ICC2,1 = 0.88, nondominant ICC2,1 = 0.91). Women performed the test significantly faster than men, and nonfreezers significantly faster than freezers. For either hand, age, bradykinesia, and freezing of gait scores individually predicted significant portions of the variance in 9HPT time. Sex also was a significant predictor, but for the nondominant hand only. Tremor and rigidity did not predict performance. DISCUSSION AND CONCLUSIONS: The 9HPT appears to be a clinically useful measure for assessing upper extremity function in individuals with PD. The 9HPT has advantages over previously used methods including standardization, known normative values for healthy controls, commercial availability, transportability, and ease of administration.

Eccentric exercise versus usual-care with older cancer survivors: the impact on muscle and mobility--an exploratory pilot study.

BACKGROUND: Resistance exercise programs with high compliance are needed to counter impaired muscle and mobility in older cancer survivors. To date outcomes have focused on older prostate cancer survivors, though more heterogeneous groups of older survivors are in-need. The purpose of this exploratory pilot study is to examine whether resistance exercise via negative eccentrically-induced work (RENEW) improves muscle and mobility in a diverse sample of older cancer survivors. METHODS: A total of 40 individuals (25 female, 15 male) with a mean age of 74 (± 6) years who have survived (8.4 ± 8 years) since their cancer diagnosis (breast, prostate, colorectal and lymphoma) were assigned to a RENEW group or a non-exercise Usual-care group. RENEW was performed for 12 weeks and measures of muscle size, strength, power and mobility were made pre and post training. RESULTS: RENEW induced increases in quadriceps lean tissue average cross sectional area (Pre: 43.2 ± 10.8 cm2; Post: 44.9 ± 10.9 cm2), knee extension peak strength (Pre: 248.3 ± 10.8 N; Post: 275.4 ± 10.9 N), leg extension muscle power (Pre: 198.2 ± 74.7 W; Post 255.5 ± 87.3 W), six minute walk distance (Pre: 417.2 ± 127.1 m; Post 466.9 ± 125.1 m) and a decrease on the time to safely descend stairs (Pre: 6.8 ± 4.5 s; Post 5.4 ± 2.5 s). A significant (P < 0.05) group x time interaction was noted for the muscle size and mobility improvements. CONCLUSIONS: This exploration of RENEW in a heterogeneous cohort of older cancer survivors demonstrates increases in muscle size, strength and power along with improved mobility. The efficacy of a high-force, low perceived exertion exercise suggests RENEW may be suited to older individuals who are survivors of cancer.

Characterizing gaze and postural stability deficits in people with multiple sclerosis.

BACKGROUND: People with Multiple Sclerosis (PwMS) experience a wide range of symptoms that can alter function and limit activity and community participation. Symptoms including sensory changes, weakness, fatigue and others have been well documented. However, symptoms related to changes in vestibular related function, including gaze and postural stability have not been fully explored. While some recent studies have begun to provide insight into these deficits in PwMS and have explored the use of rehabilitation paradigms for their management, much remains unknown about the full extent of these deficits. Therefore, this study aimed to characterize the presence of gaze and postural stability deficits in measures across the World Health Organization International Classification of Functioning, Disability, and Health (WHO ICF) and to examine how deficits in domains of body structure and function and activity contribute to participation level limitations. METHODS: Baseline data from 41 PwMS (mean(SD) age = 53.9(11.2), 78% female) enrolled as part of a randomized clinical trial were used in this analysis. Measures of gaze and postural stability from the ICF domains of body structure and function (Vestibular ocular reflex [VOR] gain and postural sway area), activity (computerized dynamic visual acuity [cDVA] and MiniBEST test), and participation (Dizziness handicap inventory [DHI] and Activities Balance Confidence [ABC] scale) along with demographic data were used to characterize the sample. To explore relationships between ICF domains for gaze and postural stability, univariate correlations were performed between measures from each domain using Pearson's correlations. Separate multivariate regression models examined how measures from the body structure and function and activity domains contributed to the variance in the participation level outcomes. Variance explained by the models was quantified using R-squared statistic and contribution of the independent variables were quantified using the beta coefficient (p < 0.05). RESULTS: Correlation analysis demonstrated significant relationships in the postural stability measures across domains. Specifically, between postural sway area on a firm surface and MiniBEST test score (r = -.48;p < 0.01) and MiniBEST test score and ABC score (r = 0.5;p < 0.01). Significant correlations were also found between the gaze stability measures of horizontal and vertical VOR gain (r = .68;p < 0.001), horizontal VOR gain and dynamic visual acuity (r = .38;p = 0.02), and vertical VOR gain and dynamic visual acuity (r = .54;p < 0.001). Regression models assessing postural stability, found that only the MiniBEST score significantly contributed to the variance in ABC score (p = 0.01) and the full model explained 34% of the variance in ABC score. Regression modeling of gaze stability outcomes did not produce any variable that significantly contributed to the variance in DHI score and the full model explained 18% of the variance in DHI score. CONCLUSIONS: PwMS in this sample demonstrated deficits in gaze and postural stability across the domains of the WHO ICF compared to past samples of PwMS and healthy cohorts. Correlation between measures in the different domains were present, but no strong relationship between measures of body structure and function, activity and participation level outcomes were observed. This lack of relationship across the domains is likely contributed to the relatively small sample size, the high level of variability observed in the outcomes, and the diverse presentation often seen in PwMS.

The feasibility and efficacy of eccentric exercise with older cancer survivors: a preliminary study.

INTRODUCTION: Older individuals who have survived cancer and the commensurate treatment often experience a reduced quality of life in part due to their impaired muscular abilities and deficits in mobility. The purpose of this preliminary study was to determine the feasibility and preliminary efficacy of resistance exercise via negative, eccentrically induced work (RENEW) with older cancer survivors. METHODS: Older cancer survivors with a perception of moderate muscle weakness and fatigue participated in 12 weeks of RENEW. Measures of feasibility included (1) the participant's ability to progress the total amount of work of RENEW; (2) whether peak knee extension torque production became impaired; and (3) whether RENEW induced leg muscle pain as measured on a visual analog scale. The preliminary measure of efficacy included the performance of a timed up-and-go mobility test. RESULTS: The participants significantly increased the total average work per week over the 12 weeks of RENEW. Participants increased (P < .001) their work approximately 3-fold from week 3 (7.6 [5.11 kJ) to week 12 (22.1 [14.8] kJ) without muscle pain over the 12-week RENEW training period. Knee extension peak torque production improved (11%) significantly (P = .02) (pretest: 248 [92] N; posttest: 275 [99] N) after 12 weeks of RENEW. The time to perform the up-and-go test improved (14%) significantly (P < .001) (pretest: 8.4 [2.7]; posttest: 7.2 [2.3] s) after 12 weeks of RENEW, suggesting preliminary efficacy. CONCLUSION: Collectively, RENEW appears feasible and potentially efficacious for older, weak, and fatigued cancer survivors. IMPLICATIONS FOR CANCER SURVIVORS: The use of eccentric muscle exercise may be ideally suited for older cancer survivors due to its high force and low energetic-cost capabilities.

Cost-Effectiveness of Operative Versus Nonoperative Management of Patients With Intra-articular Calcaneal Fractures.

OBJECTIVE: To assess the costs, health gains, and cost-effectiveness of operative versus nonoperative treatment of calcaneal fractures over a 5-year time horizon from both US societal and payer perspectives. METHODS: The societal perspective analysis included both direct medical costs and costs for missed work, whereas the health care payer perspective analysis included only direct medical costs associated with treatment and complications. A decision tree simulation model was developed to estimate the direct medical and indirect costs (2018 US$) and quality-adjusted life-years (QALYs) for treatment of patients sustaining intra-articular calcaneal fractures fixed with an extensile lateral approach. Direct medical costs were obtained from a large US health care system in Utah, Intermountain Healthcare, and indirect costs from the literature. Utility and probability parameters were also derived from the literature. Parameter uncertainty was explored using both one-way and probabilistic sensitivity analysis. RESULTS: From a US societal perspective, operative treatment costs less ($35,110 vs. $39,870) and yielded more QALYs (3.89 vs. 3.51) over 5 years compared with nonoperative treatment. At a willingness-to-pay threshold of $50,000 per QALY, operative fixation had an 89% probability of being cost-effective. From a health care payer perspective, operative management remained cost-effective as the incremental cost-effectiveness ratio is below the willingness-to-pay threshold of $50,000/QALY. CONCLUSION: From both US societal and health care payer perspectives, operative treatment of displaced intra-articular calcaneal fractures utilizing an extensile lateral approach is cost-effective at commonly accepted willingness-to-pay thresholds compared with nonoperative treatment over a 5-year time horizon. Patient variability may impact cost-effectiveness and should be explored in future research. LEVEL OF EVIDENCE: Economic Level III. See Instructions for Authors for a complete description of levels of evidence.

Reversing muscle and mobility deficits 1 to 4 years after TKA: a pilot study.

UNLABELLED: Muscle and mobility deficits can persist for years after a total knee arthroplasty (TKA). The purposes of this study were (1) to determine if 12 weeks of rehabilitation with resistance exercise induces increases in muscle size, strength, and mobility in individuals 1 to 4 years after a TKA; and (2) to compare the muscle and mobility outcomes of a traditional resistance exercise rehabilitation program with a rehabilitation program focused on eccentric resistance exercise. Seventeen individuals (13 women, four men; mean age, 68 years; age range, 55-80 years) with either a unilateral or bilateral TKA (total of 24 knees) were included in this matched and randomized repeated-measures rehabilitation pilot trial. Increases in quadriceps muscle volume and knee extension strength followed 12 weeks of eccentric exercise. Improvements were also noted in four mobility tests. Similar improvements were noted in the traditional group in two mobility tests. An increase in muscle size and strength and an improvement in levels of mobility can occur after 12 weeks of resistance exercise in older individuals 1 to 4 years after TKA. When the exercise mode focuses on eccentric resistance, the muscle growth response is greater as is the improvement in important mobility tasks. LEVEL OF EVIDENCE: Level II, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Short-term Effects of Manual Therapy in Patients After Surgical Fixation of Ankle and/or Hindfoot Fracture: A Randomized Clinical Trial.

BACKGROUND: Patients with surgical fixation of ankle and/or hindfoot fractures often experience decreased range of motion and loss of function following surgery and postsurgical immobilization, yet there is minimal evidence to guide care for these patients. OBJECTIVES: To assess whether manual therapy may provide short-term improvements in range of motion, muscle stiffness, gait, and balance in patients who undergo operative fixation of an ankle and/or hindfoot fracture. METHODS: In this multisite, double-blind randomized clinical trial, 72 consecutive patients who underwent open reduction internal fixation of an ankle and/or hindfoot fracture and were receiving physical therapy treatment of exercise and gait training were randomized to receive either impairment-based manual therapy (manual therapy group) or a sham manual therapy treatment of light soft tissue mobilization and proximal tibiofibular joint mobilizations (control group). Participants in both groups received 3 treatment sessions over 7 to 10 days, and outcomes were assessed immediately post intervention. Outcomes included ankle joint range of motion, muscle stiffness, gait characteristics, and balance measures. Group-by-time effects were compared using linear mixed modeling. RESULTS: There were no significant differences between the manual therapy and control groups for range of motion, gait, or balance outcomes. There was a significant difference from baseline to the final follow-up in resting gastrocnemius muscle stiffness between the manual therapy and control groups (-47.9 N/m; 95% confidence interval: -86.1, -9.8; P = .01). There was no change in muscle stiffness for the manual therapy group between baseline and final follow-up, whereas muscle stiffness increased in the control group by 6.4%. CONCLUSION: A brief course of manual therapy consisting of 3 treatment sessions over 7 to 10 days did not lead to better short-term improvement than the application of sham manual therapy for most clinical outcomes in patients after ankle and/or hindfoot fracture who were already being treated with exercise and gait training. Our results, however, suggest that manual therapy might decrease aberrant resting muscle stiffness after ankle and/or hindfoot surgical fixation. LEVEL OF EVIDENCE: Therapy, level 2. J Orthop Sports Phys Ther 2019;49(5):310-319. Epub 13 Feb 2019. doi:10.2519/jospt.2019.8864.

Eccentric exercise in rehabilitation: safety, feasibility, and application.

This nonexhaustive mini-review reports on the application of eccentric exercise in various rehabilitation populations. The two defining properties of eccentric muscle contractions--a potential for high muscle-force production at an energy cost that is uniquely low--are revisited and formatted as exercise countermeasures to muscle atrophy, weakness, and deficits in physical function. Following a dual-phase implementation, eccentric exercise that induces rehabilitation benefits without muscle damage, thereby making it both safe and feasible in rehabilitation, is described. Clinical considerations, algorithms of exercise progression, and suggested modes of eccentric exercise are presented.

Regional muscle and whole-body composition factors related to mobility in older individuals: a review.

PURPOSE: To describe previously reported locomotor muscle and whole-body composition factors related to mobility in older individuals. METHODS: A narrative review of the literature, including a combination of search terms related to muscle and whole-body composition factors and to mobility in older individuals, was carried out. Statistical measures of association and risk were consolidated to summarize the common effects between studies. RESULTS: Fifty-three studies were reviewed. Muscle and whole-body factors accounted for a substantial amount of the variability in walking speed, with coefficients of determination ranging from 0.30 to 0.47. Muscle power consistently accounted for a greater percentage of the variance in mobility than did strength. Risks associated with high fat mass presented a minimum odds ratio (OR) of 0.70 and a maximum OR of 4.07, while the minimum and maximum ORs associated with low lean mass were 0.87 and 2.30 respectively. Whole-body and regional fat deposits accounted for significant amounts of the variance in mobility. CONCLUSION: Muscle power accounts for a greater amount of the variance in the level of mobility in older individuals than does muscle strength. Whole-body fat accounts for a greater amount of the variance in level of mobility than does whole-body lean tissue. Fat stored within muscle also appears to increase the risk of a mobility limitation in older individuals.

Predicting falls in individuals with Parkinson disease: a reconsideration of clinical balance measures.

BACKGROUND AND PURPOSE: Postural control problems, falls, and fall-related injuries are a common source of morbidity in elderly individuals, especially those with Parkinson disease (PD). Clinical balance tests such as the Berg balance scale and the functional reach have been reported to be useful in assessing fall risk in elderly individuals. However, the utility of commonly used clinical balance tests as accurate screens for fall risk has not been sufficiently examined in persons with PD. The purposes of this study were to identify which commonly used clinical balance tests of persons with PD were predictive of falls, to re-examine the cutoff scores for these tests with the goal of maximizing sensitivity as well as minimizing the negative likelihood ratio, and to determine which of the clinical balance tests had the most value in predicting falls. PARTICIPANTS: Forty-five persons with a diagnosis of idiopathic PD, aged 39-90 years (mean [sd] =69.94 [11.28]; mean [sd] Hoehn and Yahr level = 2.60 [.66]) participated. METHODS: Upon initial contact with participants, demographics and fall history were gathered and baseline physical examinations were performed. Each individual underwent balance testing with the functional reach test, the Berg balance scale, the dynamic gait index, timed up and go, and the cognitive timed up and go. Fallers and nonfallers were divided based on fall history and groups were compared on balance test performance. Sensitivity, specificity, likelihood ratios, and receiver operator characteristic curves were calculated for all balance tests. RESULTS: Twenty-five (55%) participants had a history of falls. Using cut-off scores reported in previous studies, the sensitivity of all tests was low (less than 0.60) and the specificity was high (greater than 0.85). Reconsideration of the cut-off scores resulted in increased sensitivity for all tests (greater than 0.75) and low negative likelihood ratios (less then .30). DISCUSSION AND CONCLUSION: Given the large financial, psychological, and physical complications that are associated with a fall and relatively little harmful effects of fall prevention interventions, we propose consideration of cut-off scores that maximize sensitivity for individuals with PD. Regardless of the performance on any individual clinical balance test, the multifactorial nature of postural instability in PD may necessitate a battery of tests to provide the most accurate identification of fall risk.

Development of a quantitative in-shoe measurement system for assessing balance: sixteen-sensor insoles.

This work presents the first phase in the development of an in-shoe sensor system designed to evaluate balance. Sixteen force-sensitive resistors were strategically mounted to a removable insole, and the bilateral outputs were recorded. The initial results indicate that these sensors are capable of detecting subtle changes in weight distribution, corresponding to the subject's ability to balance. Preliminary analysis of this data found a clear correlation between the ability to balance and the state of health of the subject.

Systems model guided balance rehabilitation in an individual with declarative memory deficits and a total knee arthroplasty: a case report.

BACKGROUND AND PURPOSE: The clinical management of functional mobility problems of individuals with primary musculoskeletal impairments is complicated by the concurrent presence of neurologic diagnoses. There are few case descriptions present in the literature of clinical decision making in the context of combined musculoskeletal and neurologic impairments. The purpose of this case report is to describe the application and use of a systems model of motor control for defining the appropriate rehabilitation program for an individual with both orthopedic and neurologic impairments leading to complaints of frequent losses of balance and falls during community mobility. DESCRIPTION: RG was a 67-year-old male referred to physical therapy because of balance problems. Review of his previous medical history revealed that he had suffered an anoxic brain injury 5 years earlier but had recovered full independence in activities of daily living (ADLs) with shortterm memory deficits being the primary residual effect of the brain injury. His balance problems developed only after having undergone a unilateral total knee arthroplasty 4 months prior to his initial physical therapy examination. Through examination and evaluation, RG's problems were determined to be consistent with postsurgery induced deconditioning coupled with anoxic brain injury related motor and cognitive deficits. INTERVENTION AND OUTCOMES: Physical therapy intervention focused on increasing RG's strength, decreasing the range of motion limitations in his lower extremities, balance exercises specific to his dynamic balance deficits, as well as increased amounts of practice to maximize procedural learning. Upon completion of his initial episode of care, RG's musculoskeletal impairments had improved; his scores on balance tests had increased, and his frequency of falls had decreased. Following his discharge, RG continued with a physical therapist designed secondary prevention program. DISCUSSION: This case report describes the successful rehabilitation of an individual with concurrent orthopedic and neurologic diagnoses. Important components of this rehabilitation course include: (1) the application of a systems model of motor control to guide clinical interventions, (2) the consideration of the effects of memory deficits on rehabilitation outcomes, and (3) the utilization of a secondary prevention program to prevent reoccurrence of balance problems.