Destabilizing and stabilizing forces to assess equilibrium during everyday activities.

Postural stability is essential to functional activities. This paper presents a new model of dynamic stability which takes into account both the equilibrium associated with the body position over the base of support (destabilizing force) and the effort the subject needs to produce to keep his/her centre of mass inside the base of support (stabilizing force). The ratio between these two forces (destabilizing over stabilizing) is calculated to provide an overall index of stability for an individual. Preliminary results from data collected during walking at preferred and maximal safe speed in four older adults (aged from 64 to 84yr) showed that both forces are lower for subjects with reduced maximal gait speed. In addition, the stabilizing force increases by 2-3 times from preferred to maximal speed, while the destabilizing force barely changes with gait speed. Overall, the model through the index of stability attributes lower dynamic stability to subjects with lower maximal gait speed. These preliminary results call for larger-scale studies to pursue the development and validation of the model and its application to different functional tasks.

Evaluation of postural stability in elderly with diabetic neuropathy.

OBJECTIVE: The objective of this study was to compare clinical and biomechanical characteristics of balance in diabetic polyneuropathic elderly patients and normal age-matched subjects. RESEARCH DESIGN AND METHODS: Fifteen elderly with distal neuropathy (DNP) and 15 healthy age-matched subjects were evaluated with the biomechanical variable COP-COM, which represents the distance between the center of pressure (COP) and the center of mass (COM). Measurements were taken in the quiet position with a double-leg stance, in eyes-open (EO) and eyes-closed (EC) conditions. Subjects were also assessed with clinical balance evaluations. RESULTS: The COP-COM variable was statistically significantly larger in the DNP group than in the healthy group in anterior-posterior (A/P) and medial-lateral (M/L) directions. Furthermore, the DNP group showed statistically significantly larger amplitudes of the COP-COM variable without vision. The severity of the neuropathy, as quantified using the Valk scoring system, was correlated with COP-COM amplitude in both directions. CONCLUSIONS: Evaluation of the postural stability of an elderly diabetic population using the COP-COM variable can detect a very small change in postural stability and could be helpful in identifying elderly with DNP at risk of falling.

Principal components analysis of an evaluation of the hemiplegic subject based on the Bobath approach.

An evaluation based on the Bobath approach to treatment has previously been developed and partially validated. The purpose of the present study was to verify the content validity of this evaluation with the use of a statistical approach known as principal components analysis. Thirty-eight hemiplegic subjects participated in the study. Analysis of the scores on each of six parameters (sensorium, active movements, muscle tone, reflex activity, postural reactions, and pain) was evaluated on three occasions across a 2-month period. Each time this produced three factors that contained 70% of the variation in the data set. The first component mainly reflected variations in mobility, the second mainly variations in muscle tone, and the third mainly variations in sensorium and pain. The results of such exploratory analysis highlight the fact that some of the parameters are not only important but also interrelated. These results seem to partially support the conceptual framework substantiating the Bobath approach to treatment.

An evaluation of the hemiplegic patient based on the Bobath approach: a reliability study.

The intra- and inter-rater reliability of a motor function evaluation of stroke patients, based on the Bobath approach, was studied. The intraclass correlation coefficient (ICC) was used to determine the degree of agreement between repeated measurements on the same patient taken by the same rater and between measurements taken by three raters on the same patient. In the intra-rater study, each of 19 patients was evaluated in three different sessions by one of 19 raters. In the inter-rater study 18 patients were each evaluated by three different raters. The intra-rater data were highly reliable, with ICCs of 0.95 and 0.97 for the upper and lower limbs respectively. For the inter-rater study, the ICCs were 0.79 and 0.77 for the upper and lower limbs respectively. It can therefore be concluded that this instrument, previously demonstrated to quantify patient progress, is also reliable both in intra- and inter-rater dimensions.

In home telerehabilitation for older adults after discharge from an acute hospital or rehabilitation unit: A proof-of-concept study and costs estimation.

PURPOSE: The purpose of this study is to investigate rehabilitation through teletreatment as an alternative to a physical homecare visit to deliver services to individuals at home following discharge from an acute hospital or rehabilitation unit. METHOD: Four community-living elderly people were recruited for telerehabilitation services prior being discharged from an acute-care hospital and a geriatric rehabilitation unit. Once the patient returned home, an appointment was made for the assessing therapist to take the clinical measurements (T1) in a face-to-face session. Four clinical variables were used (functional autonomy, balance, locomotor performance in walking and lower-body strength). Telerehabilitation sessions with the participants were conducted with trained personnel in the individual's home. The system used to support telerehabilitation services for this proof of concept was built around network-attached remotely-controlled pan/tilt/zoom cameras with MJPEG compression, media displays and hands-free phones. Before the patient was discharged from the physiotherapy program, the same assessing therapist visited the subject again to take the T2 measurements in a face-to-face session. The satisfaction of the health-care professional was determined for each session with the homemade questionnaire. Costs related to telerehabilitation were compared to theoretically home visits. RESULTS: All four subjects improved on the four clinical variables. Mean costs for the telerehabilitation program, comprising 12 sessions over 4 weeks was $487. CONCLUSION: Telerehabilitation seems to be a practical alternative for dispensing rehabilitation services after patients are discharged from an acute hospital or rehabilitation unit.

Intrasession reliability of the "center of pressure minus center of mass" variable of postural control in the healthy elderly.

OBJECTIVES: To estimate the intrasession reliability of a single measure of the biomechanical variable "center of pressure minus center of mass" (COP-COM) to determine, first, how many trials must be averaged to obtain a reliable measure of postural stability, and second, the minimal metrically detectable change of the COP-COM. PARTICIPANTS: Community-living, healthy, elderly people over 60 years of age (n = 7). DESIGN: Measurements were made in double leg stance, eyes-open condition. Nine successive trials, with rests between, were carried out for each subject. DATA ANALYSIS: Intraclass correlation coefficients (ICCs). MAIN OUTCOME MEASURE: The biomechanical variable COP-COM, which represents the distance between the center of pressure and the center of mass, was measured from two force platforms and three position sensors. RESULTS: The ICCs obtained for one measure of the COP-COM were .79 in the anterior-posterior (AP) direction and .69 in mediolateral (ML) direction. With four trials, the COP-COM variable is reliable at .94 in the AP direction and .90 in the ML direction. Minimal metrically detectable changes were .10 mm (AP) and .16 mm (ML). CONCLUSION: Using four repetitions of the COP-COM variable provides a reliable measurement of postural stability.

Screening older adults at risk of falling with the Tinetti balance scale.

In a prospective study of 225 community dwelling people 75 years and older, we tested the validity of the Tinetti balance scale to predict individuals who will fall at least once during the following year. A score of 36 or less identified 7 of 10 fallers with 70% sensitivity and 52% specificity. With this cut-off score, 53% of the individuals were screened positive and presented a two-fold risk of falling. These characteristics support the use of this test to screen older people at risk of falling in order to include them in a preventive intervention.

Postural control in the elderly: an analysis of test-retest and interrater reliability of the COP-COM variable.

OBJECTIVES: To estimate the test-retest and interrater reliability of the center of pressure-center of mass (COP-COM) variable of postural control in the elderly. DESIGN: The biomechanic variable COP-COM, which represents the distance between the COP and the COM, was determined from 2 AMTI force platforms and 3 OPTOTRAK position sensors. Measurements were taken in quiet position, double leg stance, and eyes open and eyes closed conditions. SETTING: Laboratory environment. PARTICIPANTS: Forty-five healthy subjects, 8 patients with diabetes neuropathy, and 7 stroke survivors, all of whom were at least 60 years old. INTERVENTIONS: Subjects were evaluated on 2 separate occasions within 7 days by the same evaluator to determine test-retest reliability. Interrater reliability was determined the same day. MAIN OUTCOME MEASURES: The biomechanic variable COP-COM, which represents the distance between the COP and the COM in terms of root mean square. The mean of 4 trials of the COP-COM variable for each condition was used for statistical analysis. Intraclass correlation coefficients (ICCs) were used. RESULTS: The COP-COM variable has good reliability for both the test-retest and interrater studies, but its reliability varies according to the direction of the COP-COM. For the test-retest and interrater studies, the ICC ranged from.89 to.93 in the anteroposterior direction and from.74 to.79 in the mediolateral direction. CONCLUSION: The equivalence of the test-retest and interrater coefficients obtained suggests that the measurement error of the COP-COM variable is mainly linked to the biologic variability of this measure over a short period of time. Using the mean of 4 trials stabilizes the COP-COM variable enough to be potentially used to evaluate clinical change.

An evaluation of the hemiplegic subject based on the Bobath approach. Part III. A validation study.

Sixty-two hemiplegic subjects were treated with the Bobath approach for a period of three months. During this time they were evaluated on three occasions. The testing battery consisted of a Bobath evaluation, the Brunnstrom scale, the Fugl-Meyer test, the Upper Extremity Functional Test (UEFT) and the Present Pain Intensity (PPI) of the McGill pain questionnaire. A Friedman analysis of variance showed that, except for pain, all the protocols used disclosed significant progress (p less than 0.001) over time in terms of motor recovery. Except for pain, the results of the Bobath evaluation were significantly correlated (Spearman's Rho, p less than 0.001) with the results of the other testing procedures. It is concluded that the new Bobath evaluation proposed in a previous paper is as sensitive in depicting progress in motor recovery over time as are the other testing procedures used. Furthermore, this new evaluation seems to be measuring similar properties to the other tests. However, pain (PPI) appears not to be an important dependent variable.

An evaluation of the hemiplegic subject based on the Bobath approach. Part II: The evaluation protocol.

A protocol of evaluation of the hemiplegic patient based on the Bobath approach to treatment is presented. Six parameters are evaluated: sensorium, muscle tone, reflex activity, active movement, postural reactions and pain. The first and last of these are included because of their possible effects on the motor recovery process of the hemiplegic patient. The other four are directly borrowed from the Bobath modality of treatment. For each of these parameters, the procedures are given for its evaluation along with its respective rating scales. These scales are of an ordinal nature ranging from 0 to 3. It is suggested that this new evaluation protocol is fully compatible with the therapeutic modality developed by Bobath and as well is adequate to quantify patient progress in the principle aspects treated by this well used rehabilitation approach.

An evaluation of the hemiplegic subject based on the Bobath approach. Part I: The model.

An evaluation, based on the Bobath approach to treatment has been developed. A model, substantiating this evaluation is presented. In this model, the three stages of motor recovery presented by Bobath have been extended to six, to better follow the progression of the patient. Six parameters have also been identified. These are the elements to be quantified so that the progress of the patient through the stages of motor recovery can be followed. Four of these parameters are borrowed from the Bobath approach, that is: postural reaction, muscle tone, reflex activity and active movement. Two have been added: sensorium and pain. An accompanying paper presents the evaluation protocol along with the operational definition of each of these parameters.