Clinical application of the Hybrid Assistive Limb (HAL) for gait training—a systematic review

The objective of this cross-sectional study was to compare scores on the Balance Scale with laboratory measures of postural sway and other clinical measures of balance and mobility. Thirty-one elderly subjects were assessed on the clinical measures and the laboratory tests of postural sway while standing still and in response to pseudorandom movements of the platform. The average correlation between the Balance Scale and the spontaneous sway measures was -.55. It was slightly lower (r = -.38) for the same parameters measured during the pseudorandom tests. There were high correlations between the Balance Scale and the Balance Sub-Scale developed by Tinetti (r = .91), Barthel Mobility sub-scale (r = .67), and timed "Up and Go" (r = -.76). The Balance Scale was the most efficient measure (effect size > 1) to statistically discriminate between subjects according to their use of each type of mobility aide (walker, cane, no aids). These data contribute to existing information on the performance of the Balance Scale and supports the validity of the Balance Scale in this geriatric population.

Gait velocity is a powerful indicator of function and prognosis after stroke. Gait velocity can be stratified into clinically meaningful functional ambulation classes, such as household ambulation ( 0.8 m/s). The purpose of the current study was to determine whether changes in velocity-based community ambulation classification were related to clinically meaningful changes in stroke-related function and quality of life. In subacute stroke survivors with mild to moderate deficits who participated in a randomized clinical trial of stroke rehabilitation and had a baseline gait velocity of 0.8 m/s or less, we assessed the effect of success versus failure to achieve a transition to the next class on function and quality of life according to domains of the Stroke Impact Scale (SIS). Of 64 eligible participants, 19 were initially household ambulators, and 12 of them (68%) transitioned to limited community ambulation, whereas of 45 initially limited community ambulators, 17 (38%) became full community ambulators. Function and quality-of-life SIS scores after treatment were significantly higher among survivors who achieved a favorable transition compared with those who did not. Among household ambulators, those who transitioned to limited or full community ambulation had significantly better SIS scores in mobility (P=0.0299) and participation (P=0.0277). Among limited community ambulators, those who achieved the transition to full community ambulatory status had significantly better scores in SIS participation (P=0.0085). A gait velocity gain that results in a transition to a higher class of ambulation results in better function and quality of life, especially for household ambulators. Household ambulators possibly had more severe stroke deficits, reducing the risk of "ceiling" effects in SIS-measured activities of daily living and instrumental activities of daily living. Outcome assessment based on transitions within a mobility classification scheme that is rooted in gait velocity yields potentially meaningful indicators of clinical benefit. Outcomes should be selected that are clinically meaningful for all levels of severity.

The limited walking ability that follows a stroke restricts the patient's independent mobility about the home and community, a significant social handicap. To improve the in-hospital prediction of functional outcome, the relationships between impairment, disability, and handicap were assessed with clinical measures in 147 stroke patients. The patients' level of functional walking ability at home and in the community was assigned by expert clinicians to one of the six categories of a modified Hoffer Functional Ambulation scale at least 3 months after discharge. A 19-item questionnaire was further used to assess current customary mobility of the subjects. Functional muscle strength and proprioception were tested, and walking velocity was measured. The significant indicators of impairment, upright motor control knee flexion and extension strength, differentiated household from community ambulators. The addition of velocity improved the functional prediction. Proprioception was clinically normal in all walkers. The validity of the criteria for the six levels of walking handicap was confirmed statistically. Stepwise discriminant analysis reduced the ambulation activities on the questionnaire from 19 to 7. Redefinition of the criteria for patient classification using the coefficients and constants of the seven critical functions improved the prediction of patient walking ability to 84%. The results of this study offer a quantitative method of relating the social disadvantage of stroke patients to the impairment and disability sustained. The measurement of therapeutic outcome in relation to the social advantage for the patient would allow more efficient standardization of treatment and services.