The Influence of Seat Height on Hemiplegic-pattern Propulsion of Manual Wheelchairs

This study evaluates the effect of seat height on hemiplegic-pattern wheelchair propulsion. Each subject will act as their own control and measures will be obtained in a one sixty minute session. Five seat heights relative to the subject's leg length will be measured in a random order to see the effect on forward and backwards wheelchair propulsion.

Many people who have suffered a stroke require a wheelchair for mobility. Hemiplegia is a common result of stroke.Many people with hemiplegia propel themselves using their sound-side arms and legs ("hemiplegic-pattern propulsion") in manual wheelchairs.Often people using this pattern are prescribed wheelchairs with a reduced seat height to facilitate foot propulsion. Despite the seeming obviousness of the need to lower the seat height for people who use foot propulsion,there is little available evidence to help establish optimal wheelchair seat height. The study objective is to test the hypothesis that there is an optimum wheelchair seat height (expressed as a percentage of the lower leg length) for hemiplegic-pattern wheelchair propulsion. The investigators expect that the optimum seat height will be lower than that usually used for wheelchairs that are hand-propelled. A single-subject design with able-bodied participants will be used to investigate 5 randomized seat heights. The 5 seat heights will be set relative to the subjects leg length at a single 60 minute data collection session All measures will be obtained during one session. The optimal seat height will be chosen based on wheelchair propulsion speed, push frequency and effectiveness over 10m going forward on smooth surface, and 5m going backwards over a soft surface.

Randomly assigned 5 wheelchair seat heights ranging from very low (2" below) to very high (2" above) the lower leg length of the participant.

Seat height set relative to participant's leg length with neutral set at the measured lower leg length

Investigator developed questionnaire asking how difficult it was to perform the propulsion test. The participant will self-report his/her level of difficulty for this skill using a five-point Likert scale (1 =very easy, 2=somewhat easy, 3=neither easy nor difficult, 4= somewhat difficult and 5=very difficult). A single number will be reported.

Inclusion Criteria: willing to participate is right-hand dominant (to simplify wheelchair and laboratory set-up) has a subjective unshod height of ≤ 183 cm (6'0") is able to be comfortably seated in the manual wheelchair used for the study is 18 years of age or older, is alert and cooperative is competent to provide informed consent is able to communicate in English does not have an unstable medical condition Exclusion Criteria: -

Heinrichs ND, Kirby RL, Smith C, Russell KFJ, Theriault CJ, Doucette SP. Effect of seat height on manual wheelchair foot propulsion, a repeated-measures crossover study: part 1 - wheeling forward on a smooth level surface. Disabil Rehabil Assist Technol. 2021 Nov;16(8):831-839. doi: 10.1080/17483107.2020.1741036. Epub 2020 Apr 2.

Heinrichs ND, Kirby RL, Smith C, Russell KFJ, Theriault CJ, Doucette SP. Effect of seat height on manual wheelchair foot propulsion, a repeated-measures crossover study: part 2 - wheeling backward on a soft surface. Disabil Rehabil Assist Technol. 2022 Apr;17(3):325-330. doi: 10.1080/17483107.2020.1782490. Epub 2020 Jun 27.