Hemiplegic gait. Relationships between walking speed and other temporal parameters.

It has been asserted that speed alone is an effective indicator of the degree of gait abnormality. To determine the validity of this assertion, relationships between velocity and 18 other temporal gait parameters were determined in 25 patients with a first hemispheric stroke resulting in hemiplegia or hemiparesis of at least one month duration. Gait characteristics were recorded using footswitchs connected to a portable computerized monitoring device. Velocity was found to be significantly correlated with cadence, mean cycle duration, mean cycle length, hemiplegic limb stance phase duration, nonhemiplegic limb stance phase duration and percent, nonhemiplegic limb swing phase percent, double support phase duration and percent, hemiplegic limb swing/stance phase ratio, nonhemiplegic limb swing/stance phase ratio, and swing phase symmetry ratio but not with the hemiplegic limb stance phase percent, hemiplegic limb swing phase duration and percent, nonhemiplegic limb swing phase duration, stance phase symmetry ratio, and overall asymmetry ratio. Velocity is related to most, but not all, of the other temporal measures of hemiplegic gait. A comprehensive gait evaluation should also include characterization of the degree of asymmetry and descriptions of individual phase durations and proportions (particularly hemiplegic stance and swing percentages).

Frequency measures of behavior for assistive technology and rehabilitation.

Documenting assistive technology outcomes has grown in importance, but outcome measurement remains problematic. A new approach uses natural science measures and a model (selectionism) from the field of Behavior Analysis. Selectionism defines behaviors by their effects (functional performance) and the environment (including technology) within which they occur, and explicitly treats variation in patterns of behavior over time for individuals (intervention effects). Its basic metric is frequency of behaviors (count per unit time) which is similar to robust engineering measures like centimeters, grams, and seconds. This approach eliminates many of the problems inherent to more traditional psychometrics. Selectionism based on frequencies also provides an empirical structure or taxonomy to organize efforts and outcomes, unified by the notion of fluency. Composite behaviors are combinations of smaller component behaviors that are required for performance of the composite. A frequency above which a component behavior is readily retained, generalized, and recruited into the more complex composite behavior is called fluency; thus individuals fluent on the critical components easily and efficiently demonstrate the composite. This model suggests that when assistive technology interventions raise component behavior frequencies to fluent levels, they will be integrated usefully into an individual's life. This selectionistic approach has been used successfully in the field of education. It has the added benefit of not only empirically defining measurable outcomes, but also of providing useful ongoing measurement of change during treatment. This paper briefly describes this "Precision Measurement" strategy and its data-driven feedback process and makes suggestions for further research and development efforts. The method provides a basis for better documentation, control, and outcomes of assistive technology and related interventions.

The timer-logger-communicator gait monitor: recording temporal gait parameters using a portable computerized device.

A portable microprocessor-based device, the timer-logger-communicator (TLC), was adapted and connected to footswitches to monitor and record temporal gait parameters in 25 hemiplegic and 30 normal subjects. Controls walked at 1.36 m/s with symmetric gait. Hemiplegic subjects had a mean walking speed of 0.43 m/s, asymmetric gait, and varying proportions of time spent in each phase, consistent with previously reported gait parameters. Trends in objective gait measures more closely paralleled trends in functional ambulation classification than in Brunnstrom motor recovery stages. The TLC gait monitor is a useful instrument to measure temporal parameters of gait in the clinical setting.

Ordinal scales and foundations of misinference.

Fundamental deficiencies in the information provided by an ordinal scale constrain the logical inferences that can be drawn; inferences about progress in treatment are particularly vulnerable. Ignoring or denying the limitations of scale information will have serious practical and economic consequences. Currently, there is a high demand for functional assessment scales within the rehabilitation community. It is hoped that such scales will satisfy the very real need for measures of function which reflect the impact of treatment on patient progress. Unfortunately, some commonly used evaluation instruments are not well suited to this task. The underlying rationale for clinical decision-making based on these scales is examined.

The Communication Analysis System.

The Communication Analysis System (CAS) was developed to facilitate efficient, effective treatment of conversational performance for persons with aphasia. The CAS provides frequent, objective, accurate, ratio-quality measures of ten classes of communicative behaviors for the patient and 11 for the clinician. The clinician using the CAS records the time of occurrence of communicative behaviors by a single keystroke on a keypad attached to an inexpensive microcomputer. The CAS software permits the analysis of data before the next clinical session and includes a method for assessing accuracy and reliability. Sample between-session data show the progress of one patient over several months, whereas within-session data illustrate a use of the CAS to measure a patient's performance under different communicative conditions. Simultaneously, measures of the clinician's communicative performance provide an accurate record of the treatment. This, in turn, allows observation of changes in the patient's behavior as a function of changes in the clinician's behavior. Clinical treatment can thereby be tailored precisely to the individual, optimizing the patient's rehabilitation.

Wheelchair-based mobile measurement of behavior for pressure sore prevention.

A recently developed device which provides continuous, direct monitoring of the pressure relief performance of persons confined to wheelchairs is reported. A custom portable computer records the data, which is transferred for analysis to an Apple IIe. The mobile computer can also signal the patient to relieve pressure on the basis of preset criteria and the patient's performance. Teaching lift-offs to prevent ischial pressure sores is the object. Data collected with the device are used clinically and for research. Examples of such data are presented. The benefits of the device are reviewed.

Wheelchair push-ups: measuring pressure relief frequency.

Ischial pressure sores (PS) are a long-recognized complication of wheelchair confinement, yet teaching spinal-cord patients to establish lift-off behavior habitually and permanently remains a challenge. A new device was developed to record automatically and continuously the wheelchair lift-off behavior of spinal-cord injured patients. Data from seven patients who used the device for between 768 and 1800 hours each are reported. The device was used to monitor longitudinally the behavioral compliance of each individual with prescribed lift-off intervals using standard teaching procedures. Wide variability between patients and within patients over time was found. Experimental interventions including the use of an electronic timer and written and oral feedback of the previous day's data also varied in their effectiveness. Data from one patient who developed a pressure sore while being monitored suggest that there is no simple relationship between lift-off intervals and PS formation.

Learning goals during initial rehabilitation hospitalization.

While learning theory and various clinical applications play an increasingly significant role in the design and delivery of rehabilitation services, data to determine the extent that teaching/learning are integral to rehabilitation goals are lacking. Medical records of 20 first admission spinal cord injured patients were analyzed for the proportion of teaching/learning goals, plans, and activities entered by professional disciplines on the rehabilitation team. A classification system for medical chart entries was devised for this purpose. Results indicated that 65% of the total chart entries reflected teaching/learning or attempts to accelerate or decelerate specific behaviors. Across professional disciplines nursing showed the highest proportion of chart entries focused on patient teaching/learning. Present findings support recent trends toward systematic and more sophisticated application of learning theory and technology, and suggest that professional preparation of rehabilitation personnel should include training in how to teach and how to facilitate skill acquisition.