Clinical Corner addressed rigid frame wheelchairs in the article, Understanding Choices in Rigid Wheelchairs, in March 2019. The article described what a rigid wheelchair is, how some models may permit folding (e.g., with fold-down back posts), and why a rigid wheelchair tends to offer greater efficiency of propulsion over a wheelchair with a folding cross-brace. The article also outlined various choices in rigid frame wheelchairs, including open frame and closed frame designs, "active" models and adjustable models, and why so many choices are available on the market, even within a single manufacturer. If you missed that article, click here to read it. This month, Clinical Corner will continue to look at rigid frame wheelchairs, with a focus on frame length and why it is important to understand choices offered.
A choice on frame length – between classic and standard – is offered on some models of rigid frame wheelchairs. What does that mean? As the graphic below illustrates, the classic style of frame is longer than a standard style. The length of the seat sling, as measured from the front of the back post to the front edge of the seat sling, is the same on both frame styles. When measuring from the seat sling to the front frame bend angle, the standard frame is 1.5” shorter than the classic position. The choice allows individuals to select a frame style that suits their preferences and needs.
All other things being equal in terms of wheelchair set up, the choice of frame length will affect the wheelbase of the wheelchair, turning radius, and maneuverability. A classic style frame will have a slightly longer wheelbase and slightly larger turning radius than a standard frame wheelchair. This may impact an individual in a tight, cramped environment, such as a washroom. A longer wheelbase, however, may offer the potential to go over bumps more easily and a smoother ride than a wheelchair with a shorter wheelbase.
Again, all other things being equal in terms of wheelchair set up, the choice of standard style frame or classic frame will influence the weight distribution between the front casters and the rear wheels, which may affect maneuverability. Since the standard frame is shorter than the classic frame, the front casters may be closer to an individual's centre of mass, which could mean that the front casters take a larger proportion of load in a standard frame than in a classic frame style. When the front casters are further away from an individual's centre of mass, less load is distributed through the front casters, which can effect maneuverability. If the load distribution between the front casters and rear wheels is not ideal, rolling resistance and maneuverability will be negatively impacted.
Frame length is one of the choices when scripting rigid frame wheelchairs. Other considerations will be addressed in future Clinical Corner articles.
As always, please provide your comments, questions and suggestions regarding Clinical Corner. Please email me at Sheilagh.Sherman@sunmed.com. I look forward to hearing from you!
Sheilagh Sherman, BA, BHScOT, MHM, OT Reg. (Ont.)
Clinical Education Manager
Sunrise Medical Canada
Note: The content of this article is not meant to be prescriptive; rather, it is meant as a general resource for clinicians to then use clinical reasoning skills to determine optimal solutions for individual clients. Sheilagh is unable to answer questions from members of the general public. Members of the general public are directed to their own therapists or other health care professionals to ask questions regarding needs.
This article is © Sunrise Medical, Inc., 2020 and cannot be copied, distributed, or otherwise reproduced in whole or in part without the express written permission of Sunrise Medical Canada.