Oil and water don’t mix well and we often assume that molded seating and movement don’t mix either. Why? Well, a molded seat or back provides very intimate contact with the client’s body. If, for example, the seat to back angle changes, this can change the alignment of the client in relation to these intimate contours.
A client may not remain in alignment with a molded back when extending and may experience increased shear forces in relation to the back due to this movement and force. By providing movement in response to force, alignment may actually be improved and these shear forces decreased.
“Jackson” (named has been changed) was in a car accident when he was only 6 years old and sustained a significant brain injury. As a result, he was unable to move himself, communicate with others, or control anything in his environment. He has been using various mobility bases since that time.
Recently I had a nice conversation with a colleague about Dynamic Seating. Joe McKnight is Director of Business Development in California, Nevada, and Arizona for Numotion, and he has been in the wheelchair seating and mobility field for a long time – probably longer than he would like to admit! Having that much experience provides a unique view. Joe states that “how we practiced 30 years ago and how we practice now should be different. We need to re-evaluate how we are doing things and how we need to change.”
Our last blog discussed providing dynamic movement at the pelvis. If the pelvis moves posteriorly, the trunk will move posteriorly as well. So if posterior movement of the trunk is desired, dynamic seating components which allow posterior movement of the pelvis are provided, namely a dynamic back rest, which opens the seat to back angle in response to client movement and force. This movement may be utilized to protect back mounting hardware, absorb extensor forces and simply to provide active movement. If the client experiences a loss of trunk position upon return to upright, it is important to ensure that adequate lateral and anterior trunk support is used. Continue reading →
Dynamic movement can be provided at various areas of the body where movement is possible from a seated posture. The dynamic component allows movement beyond the usual seated posture, such as into increased trunk extension, and then assists with the client returning to upright. Ideally, the return to upright does not lead to a loss of position, such as a posterior pelvic tilt.
Most frequently, movement is allowed posteriorly, opening the seat to back angle. Upon return to upright, the pelvis is at risk of falling into a posterior tilt and being pushed forward. The pivot point of the dynamic component is critical to the client returning to upright with a neutral pelvic position, and should be as close to the natural pivot point as possible (see photo).
Some components only allow very small movement and are designed primarily to protect against a broken wheelchair backrest or other seating hardware breakage. These components are less likely to lead to a loss of client position as so little movement occurs.
Our last blog discussed how dynamic seating can provide vestibular input for clients. Vestibular input can, in turn, calm agitated clients and help sub-aroused clients be more alert. Movement can also increase comfort and general muscle activity.
Dynamic Seating moves in response to client forces. Many clients move, not due to increased extensor tone, but rather for the explicit purpose of moving. We all tend to seek out movement. We are wired to move and movement has so many benefits. Movement can calm, arouse, work muscles and provide comfort by varying our position. From a sensory standpoint, movement provides vestibular input.
As discussed in our last 2 blogs, dynamic seating is commonly used to prevent breakage of the wheelchair seating system and frame. Another common application of dynamic seating is to diffuse force and reduce overall extension. Continue reading →