Proper use of a Leveraged Lift via the Body Lever is the key to a successful Floor-to-Wheelchair transfer (FWT). Yet, few people understand it’s dynamics. As a result, its use is not taught in a systemic manner to wheelchair users. Many of those that utilize it, don’t realize it. Those that don’t use it, don’t know that they should or could use it. As a result, many FWT fail or are harder to perform than they could be.
A Leveraged Lift is based on the physics of levers. A lever is a simple machine that amplifies mechanical effort. There are three components to a lever – the Base, the Fulcrum, and the Lever Arm. All three components must be present for the lever to function.
In the case of the FWT transfer, the wheelchair user makes a lever out of his (or her) body and the environment with the goal of enabling the “work” of transferring his body from the floor up to his wheelchair. The Leveraged Lift increases his mechanical advantage and makes it possible (or easier) to raise a significant amount of weight (his body) with the use of only his upper body.
For the Side Approach FWT, the wheelchair user makes a certain type of Body Lever. The base is the person’s feet on the ground. The fulcrum is his (or her) knees. And the lever arm is his body from head to butt.
In the diagram above, the Body Lever is actually made up of two lever actions. The 1st lever (Class I) uses the weight of the person’s upper body as a counter weight to his butt/hips. The more weight he can get forward in front of his knees (fulcrum/pivot point), the “lighter” his butt/hips become. This lever uses pull of gravity on the person’s upper body to provide lifting to the person’s lower body. It is essentially “free” effort.
The 2nd lever (Class III), uses the lifting effort of the person’s arms to raise his butt/hips by pivoting (reducing the bend) at his knees. This type of lever doesn’t make the load easier to lift, but it allows for greater lifting height along with more lifting effort.
Both of these levers act together to create the maximum lifting height with the least amount of effort which are essential for a successful FWT. Not using these levers means less lifting height and more lifting effort. Therefore, people with very high muscle strength and/or long arms may not need the Body Lever (until they do). But most wheelchair users do need it.
A failed WFT by a person with sufficient strength and flexibility can be the result of not creating an adequate Body Lever or the deterioration of the Body Lever mid-transfer. Therefore, proper technical training of Body Lever mechanics is imperative for performing safe and effective Floor-to-Wheelchair transfers.