Wheelchairs biomechanics, prosthetic development

08/02/04

Adaptive propulsion strategies protect some manual wheelchair users from injury, pg 385 This study compares the propulsion biomechanics of manual wheelchair users with and without upper-limb impairment. Forty-seven manual wheelchair users propelled an instrumented wheelchair ergometer while a 3-D motion analysis system collected joint kinematic and temporal data, as well as hand rim and joint kinetics. The data suggest manual wheelchair users with upper-limb impairment adopt strategies to remain independent, and some of these strategies may protect them from the development of secondary upper-limb pathologies.

Athletics has no impact on should pain in wheelchair users, pg 395

This study investigates the prevalence and identity of shoulder pathology in athletic and nonathletic manual wheelchair users. Fifty-two manual wheelchair users completed a survey regarding the nature of their injury, sports involvement, history, and presence of current and/or past shoulder pathology. Volunteers currently experiencing shoulder pain underwent a clinical examination of both shoulders. No difference was found in the incidence of shoulder pain, past or present, between athletes and nonathletes. These findings indicate that involvement in athletics does not increase, nor decrease, the risk of shoulder pain in the manual wheelchair population.

Seat position impacts wheelchair use, pg 403

This study examines the effect of seat position on hand rim biomechanics. Information on hand rim forces and motion were collected in a motion analysis laboratory while volunteers propelled a wheelchair over a smooth level floor at a self-selected speed. The axle position was changed to examine the effect seat position has on wheelchair propulsion biomechanics. A seat unit positioned behind the drive wheels improved some wheelchair timing variables. Wheelchair timing measures can be improved by altering wheelchair fit.

ACSM target heart rate guidelines appropriate for female wheelchair athletes, pg 415

This study examines heart rate-oxygen uptake rate relationship in female wheelchair athletes (WAs) to determine the appropriateness of using American College of Sports Medicine (ACSM) target heart rates for training prescription. Ten WAs completed a series of physical activities on a wheelchair ergometer. Oxygen uptake and heart rate were recorded. Limited exercise prescription guidelines have been established for persons who perform wheelchair exercise and the most recent work has been restricted to males. The results suggest that training programs prescribed on the basis of ACSM target heart rate guidelines need not be altered for trained female WAs.

Wheel camber increases sprinting force in wheelchair athletes, pg 421

This study investigates the effects of rear wheel camber—today used mainly in the handibasket championship — on the propulsion cycle. Eight males performed three sprints as measured by a wheelchair ergometer. Data suggest that residual torque increases in proportion to the increase in wheel camber. This could explain other study results, which show a decrease in velocity and an increase in power output and in the time of the propelling phase, in relation to the wheel camber. These results provide information that must be taken into account in the search for the optimal regulation of the user-to-chair interface.

The Smart Wheelchair Component System provides mobility for people with severe disability, pg 429

This article describes the development and evaluation of a prototype of the Smart Wheelchair Component System (SWCS). The SWCS was evaluated on four different wheelchairs using an array of specific navigation tasks and a reliability test in which each wheelchair was configured to wander randomly within an enclosed area populated with obstacles. The SWCS met initial design criteria for safety and performance on a range of wheelchairs. The SWCS can be added to a variety of commercial power wheelchairs to provide independent mobility to individuals with severe physical, perceptual or cognitive impairments.

Portable wheelchair ramps and curb and vehicle access, pg 443

This study evaluates portable wheelchair ramps for ease of use when climbing curbs or accessing vehicles. Wheelchair users and caregivers, in a simulated curb and test vehicle, rated 12 portable ramps. Ramp ease of use was greatly influenced by the design and the location of specific accessories, such as carrying handles and locks. Wheelchairs users preferred single-wide platform ramps and caregivers preferred channel ramps. Investigators found that ramps were delivered without instructions, moved during use, and were too narrow. These findings provide insight into the benefits and limitations of different ramp designs and implications for curb and vehicle access.

Smoking, foot care linked to self-efficacy in people with amputations, pg 453

This study describes the extent to which veterans with a nontraumatic, unilateral lower-limb amputation engage in two health-related behaviors, foot care and smoking, and if health beliefs and psychological well-being are related to those health behaviors. Forty-four veterans participated in a telephone survey. Most veterans reported practicing good foot care. Nearly a third smoked. A belief in one's ability to engage in good foot care and that good foot care reduces the risk of future foot problems were significantly correlated with daily foot care practices. In addition, psychological well-being was significantly related to foot care and smoking status.

Neuroprosthesis restores grasp-release hand function to individuals with SCI, pg 461

This study investigates the use of myoelectric signals (MES) from wrist muscles to control a hand grasp neuroprosthesis. MES from the wrist flexor and extensor muscles were recorded in five able-bodied volunteers and two volunteers with spinal cord injury. Volunteers activated 99% of the target states for at least 1 second and matched at least 87% of the target hand positions for at least 2 seconds. The hand grasp neuroprosthesis restores grasp-release hand function to individuals with cervical spinal cord injury. A MES neuroprosthesis provides an invisible and potentially more natural means for opening and closing the hand.

Study holds promise to improve therapy for people with balance disorders, pg 473

This study examines the influence of neck muscle activation level on vestibular evoked myogenic potentials (VEMPs). VEMPs are a noninvasive, indirect method to measure the inner ear balance system. VEMPs have been proposed as a reliable clinical test that may supplement the current vestibular (inner ear balance) test by providing diagnostic information about saccular and/or inferior vestibular nerve function. The saccule senses linear acceleration, such as the force of gravity, and contributes to postural stability. Patients with postural instability are at increased risk of falls.

Telerehabilitation for veterans with a lower-limb amputation or ulcer, pg 481

This study analyzes the acceptability of information available via a customized telerehabilitation system regarding patients with lower-limb ulcers or recent lower-limb amputations. Fifty-four participants were evaluated by means of still photographs and skin temperature data sent via ordinary telephone lines. Agreements were assessed between decisions made after telerehabilitation sessions and decisions made by the same rater after in-person sessions. This study provides evidence that the telerehabilitation system has the potential to present sufficient information to experienced clinicians so they can make informed decisions regarding wound management.

New prosthetic sockets system streamlines artificial limb production, pg 491

This study presents a simple method of fabricating prosthetic socket using a pressure casting (PCast) technique. Four unilateral transtibial amputees adopted a normal standing position, while placing his residual limb in a pressure chamber for socket casting. The PCast sockets were fabricated without rectification. Volunteers found the PCast sockets to be acceptable. The simplicity and potentially rapid fabrication of the PCast system makes it a useful alternative in prosthetic socket production.

Source: Eurekalert & others

Last reviewed: By John M. Grohol, Psy.D. on 21 Feb 2009
    Published on PsychCentral.com. All rights reserved.

 

 

True courage is like a kite; a contrary wind raises it higher.
~ John Petit-Senn