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Updated: Sep 30, 2026

Determining and Controlling External Power Output During Regular Handrim Wheelchair Propulsion
Published on: February 5, 2020
Pressure distribution at the seating interface of custom-molded wheelchair seats: effect of various materials
Dimitrios P Apatsidis1, Stephan E Solomonidis, Shona M Michael
1Bioengineering Unit, University of Strathclyde, Glasgow, UK. dimitrios.apatsidis@strath.ac.uk
Objective:
To identify which of 4 materials has the most favorable pressure distribution when used in custom-molded seats (CMSs) to assist clinicians in providing appropriate seating for wheelchair-bound individuals who are prone to develop pressure ulcers.
Design:
Repeated-interface pressure measurements for all materials, followed by statistical analysis.
Setting:
The general community and referral centers.
Participants:
Seven subjects, 5 with cerebral palsy, 1 with Schilder's disease, and 1 with postmeningitis effects. All subjects were seated in a CMS and had spinal deformities.
Interventions:
Viscoelastic polyurethane foams (Pudgee, Sunmate) and gels (Floam trade mark, Jay) were used as inserts in the CMSs. Evazote foam was used as a control material.
Main Outcome Measures:
Pressure readings were taken at the seat interface with pneumatic pressure sensors and the Talley Pressure Monitor. Peak pressure readings, mean pressure ratio, and peak pressure ratio for the different materials were compared.
Results:
Foams, Sunmate in particular, produced lower peak-interface pressures and also showed better pressure distribution than did gels.
Conclusion:
Foams are the preferred insert material with CMSs when increased tissue breakdown risk is present.
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