Background: Riley is a 10 year old girl with the diagnoses of cerebral palsy and autism. When I first met her, she already had quite a bit of seating and mobility equipment including a Rifton activity chair, an adaptive stroller, a gait trainer, and a power wheelchair. Riley was also using a communication device. The supplier working with Riley, Lindsey Rea, ATP of Numotion, referred her for evaluation of her driving method. Although Riley had a head array on her current power wheelchair, she demonstrated very good control of her right foot and Lindsey was hopeful this could be used for driving. Her speech language pathologists, Jill Tullman and Christie Bowers, were also interested in evaluation of Riley’s access to her communication device. While the device was set-up for eye gaze control, Riley continually attempted to access this with her right foot.
Positioning: Riley could sit independently on the floor; however, she required a stable contoured cushion to support how she accessed her assistive technology devices with her right foot. In conjunction with a contoured back, she would have adequate postural support for her functional activities.
Mobility: Riley could use a gait trainer though used the power wheelchair for longer distances and to provide more efficient mobility. Riley had had a power wheelchair for nearly 5 years at the time of the initial evaluation. During the evaluation, the attendant joystick was moved from the rear of the power wheelchair and placed at her right foot where she was able to grasp and move this with her shoe and sock removed. I determined that Riley did have more control driving with her right foot than with her head. We next needed to determine how to implement this recommendation. The joystick needed to be embedded into the right footplate itself. Specifically, I recommended the Stealth Products Mushroom joystick, as this works well for foot drivers, being quite durable for this placement. The body of the joystick would be mounted under the footplate while the handle needed to protrude above the level of the footplate toward the distal end.
Recommendations: A new power wheelchair, the Quantum Rehab Stretto, was recommended with the Mushroom joystick, as well as mounting for the communication device. The power wheelchair was shipped from Quantum Rehab to Stealth Products for the Mushroom joystick to be installed. Although Riley could use the dome shaped handle, the family ultimately used a custom 3D printed goalpost style handle which worked better for driving. She can even drive this with her shoe on! Tracking technology further optimizes her driving. The new power wheelchair also includes a seat elevator which helps Riley with transfers, as well as extends her functional reach with her right foot. A power tilt allows her to shift her weight.
Communication: Riley was also able to access her communication device using her right foot by activating specific locations on the display with her toe. We recommended a mount which would position the communication device optimally for access while still allowing Riley to also access the power wheelchair joystick. She accesses the communication device while barefoot.
Riley is truly a remarkable girl who can drive, manage her power seating, and even turn on her power wheelchair LED lighting independently! She is an awesome communicator and is ready to take on the world!
The dreaded posterior pelvic tilt. The bane of seating clinics everywhere. What is it and how can we correct this issue? The position of the pelvis determines the position of the trunk and lower extremities. Providing as neutral a pelvic position as possible improves overall posture, stability, and function.
What is a Posterior Pelvic Tilt?
A Posterior Pelvic Tilt (PPT) occurs when the top of the pelvis is tipped posteriorly. This leads to flexion of the spine, including the neck. This is sometimes referred to as sacral sitting because weight bearing may actually occur on the sacrum, rather than on the ischial tuberosities, creating a risk for pressure injuries.
What Causes a Posterior Pelvic Tilt?
Strategies to address PPT depend on the cause, so it is critical to determine why a client is moving into this position. The Mat Assessment can help us identify the culprit.
Low tone or muscle weakness in the trunk can lead to PPT as the body collapses under gravity.
Range of motion limitations in the hamstrings may pull the pelvis into PPT, particularly if the feet are pulled forward.
Range of motion limitations in hip flexion. Pushing the legs upward into flexion at the hip will push the pelvis back into PPT.
Seat depth, if too long for the client, will not allow the pelvis to move back enough on the seating surface to contact the back which provides posterior pelvic support.
Extension â€“ the client may actively extend, leading to a loss of position.
So, What can we do?
If the cause is low tone, weakness, or extension, it is critical to provide adequate posterior support of the pelvis. Firm support is required. Many backs employ a bi-angular shape to provide adequate postural support to the posterior pelvis while allowing for trunk extension.
The hamstrings cross both the pelvisand the knee, making these a multi-joint muscle. If tight hamstrings are pulling the pelvic into a PPT, opening the thigh to trunk (seat to back) angle can relieve the pull at the pelvis and decreasing the thigh to calf angle can relieve the pull at the knee
If the set depth is too long, provide the appropriate depth for the individual’s hip and knee flexion. If the client is growing, strategies are available to provide growth without compromising posture.
An over-long seat depth will pull the pelvis into a posterior pelvic tilt.
If hip flexion is limited, the seat to back angle needs to be opened to accommodate the available range of motion.
If the client has range limitations into hip flexion, flexion past available range will lead to posterior pelvic tilt.
For clients who slide forward on the seat or actively push into extension, posterior support to the pelvis is critical to prevent posterior rotation of the pelvis. However, we also need to block rotation at the front of the pelvis, and this is accomplished by limiting forward movement of the ischial tuberosities (ITs) through seating contours and an appropriately angled pelvic positioning belt. Many off the shelf cushions include an anti-thrust design to limit forward movement of the ITs.
A pelvic positioning belt placed at a 60 degree angle works with the cushion shape to prevent forward movement.
Goals Correcting a posterior pelvic tilt provides neutral alignment of the pelvis to support the anatomical curvatures of the spine, promote weightbearing on the ischial tuberosities to reduce pressure injury risk, and provide optimal alignment and stability for function. These goals can also be used as funding justifications in our documentation.