by Jeff McDaniel, ATP
Active American Mobility
Ideal wheelchair posture enforces neutral body alignment. The head is balanced over the spine, and the spine is balanced over the pelvis. The shoulders should align slightly behind the pelvis. Poor positioning causes skin irritation, loss of mobility, and breathing difficulties. A wheelchair evaluation team should perform a wheelchair evaluation for each individual’s unique ability and needs. A comfortable wheelchair position is vital for health and productivity. Along with providing mobility, a wheelchair should provide function, comfort, stability, safety, skin protection, and postural control. It goes without saying that matching the users needs to the best wheelchair is extremely important to meeting these goals. However, it is equally important to provide the accessories that work in conjunction with the wheelchair to provide the most positive outcome as possible. In order to achieve these goals, one aspect that must be considered is lower body/extremity positioning. Wheelchair users can profoundly affect the stability of their wheelchairs, a factor that should be considered in wheelchair design and in the process of wheelchair selection and training.
Many physical conditions cause an uneven pelvis, and a proper evaluation will identify the cause. Tight hamstrings and limited hip flexion causes posterior tendencies. Additionally, improper wheelchair seat depth, improper back angles, and improperly adjusted footrests can cause this tendency as well. An anteriorly tilted pelvis may result from loose hamstrings and weakened stomach muscles. A pelvic rotation and obliquity can result from uneven muscle tone, contractures, and a poor seating system. There are many types of solutions to correct and/or accommodate an uneven pelvis. One simple solution is a properly fitted and adjusted pelvic positioning belt. Both forward and backward pelvic tilt can be corrected to a certain extent with a properly positioned belt. Two point, four point, or harness belts assist positioning. For wheelchair users that present with hip extensor tone, sub-asis bars may need to be considered. Padded leg harnesses should be considered with active wheelchair users that require pelvic positioning as they allow for pelvic positioning without sacrificing pelvic mobility.
The ideal positioning of lower extremities should:
· Provide 25% loading of the legs at the feet
· Provide functional knee angle positioning within range of motion limitations
· Provide functional angle alignment within range of motion limitations
· Provide slight hip abduction within range of motion limitations
Hip adductors provide lateral support at the hips or knees. They come in numerous shapes and sizes but should not apply so much pressure that skin integrity would be compromised. It is extremely important to consider transfers when selecting hip/knee adductors; a side transfer will require removal of the pad while transferring. An abductor provides abduction of the hips and knees. These also come in various sizes and mounting options. An abductor mounts between the legs at the front of the wheelchair and again, transfers should be taken into consideration when selecting the hardware. Foot positioning must consider the range of motion at the knees. I personally feel that the footrests should be as close to 90 degrees whenever possible. This promotes stability and reach. A simple exercise is to place your feet under your chair and reach forward like you are grabbing something in front of you. Then try the same thing with your feet out in front of you. You should notice a great deal more of stability and reach when your feet are under you versus when they are in front of you. However, wheelchair configurations for adults often times to not allow for 90 degree legrests due to caster interference, so be sure and verify caster clearance when recommending this option. Angle adjustable footrests are also needed if there is an ankle range of motion limitation. Shoe holders can be attached to the footrests to restrict movement of the feet for individuals that either have no lower extremity movement or control. However, keep in mind that this option will restrict any functional movements the individual may have. Padded footboxes often times are a more effective alternative as they do allow for functional movement while providing a safe and protective foot support. Ankle huggers are also a good option, as they do not restrain the feet as much as a shoe holder. However, it is important to verify good skin integrity as they do cause sheering and pressure above the ankle.
To view these options, please see the following manufacturers. They all offer different types of options and accessories that may help wheelchair users “keep their feet on the ground” or their footplate at least.
To schedule an evaluation or consultation with Jeff please call 281-495-4400.