Page 8 - Mobility Management, September 2019

ATP Series
POSTERIOR PELVIC
One result of that natural tendency can be the “slouching” we were admonished for as kids, and that seating professionals working with wheelchair users regularly encounter.
What Posterior Pelvic
Tilt Looks Like
Wade Lucas, PT, DPT, ATP/SMS, is the Clinical Education Manager for Quantum Rehab.
“Posterior pelvic tilt,” Lucas said, “is the most common detrimental postural tendency that we see, not only in users
of mobility equipment, but people in general. When the human body is forced to hold itself up against gravity, it will naturally seek out the most stable, least fatiguing position. When a person is seated, the position of stability is often a posterior pelvic tilt, as it lowers the center of gravity.”
In layman’s terms, posterior pelvic tilt looks like slouching. Sam Hannah, ATP, Executive VP of Symmetric Designs, explained, “The wheelchair user can present as kyphotic, sacral sitting, having rounded shoulders, tight hamstrings and a forward head position. The pelvis will be tipped backward and the torso forward. The wheelchair user’s head will be forward and their eye level looking down. Their PSIS [posterior superior iliac spine] will be lower than their ASIS [anterior superior iliac spine].”
For wheelchair users and non-wheel- chair users alike, this position can
feel relaxing and comfortable, at least temporarily. So why is posterior pelvic tilt potentially a problem?
“There is frequently a lack of support from the backrest in the lower lumbar area, and there can also be increased pressure in the sacrum due to sitting in a forward position on the seat cushion,” Hannah said. “There is also increased pressure on the back due to less contact for pressure distribution.”
Lucas noted, “A posterior pelvic tilt can facilitate the development of other postural deviations throughout the rest of the body, including an increased thoracic kyphosis and forward head position. More subtly, you also see abduction and external rotation of the legs and increased weight bearing on the lateral aspects of the foot.”
TILT
Why It Happens & How Seating Can Intervene
By Laurie Watanabe
As we perform our slew of daily activities — brushing teeth, checking e-mail, sitting in conference calls, helping the kids with homework after dinner — our bodies work to make those activities possible. They breathe, pump blood, regulate temperature, and provide the energy needed to move and think. It’s hard work, so our bodies also look for opportunities to rest and maintain balance, or to conserve energy when possible.
8 SEPTEMBER 2019 | MOBILITY MANAGEMENT
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