Michelle L. Lange, OTR/L, ABDA, ATP/SMS
This blog is the final in a series on Muscle Tone. This series has addressed muscle tone itself, movement disorders, primitive reflexes, diagnoses characterized by increased muscle tone, tone management, and general wheelchair seating strategies used with this population. We will complete this series by turning our attention to Dynamic Seating for people with increased muscle tone.
Dynamic Seating is beneficial in a number of clinical scenarios, however, use with people who have increased tone is undoubtedly the most common application.
Dynamic Seating is beneficial in a number of clinical scenarios, however, use with people who have increased tone is undoubtedly the most common application. Dynamic Seating absorbs and diffuses force created by increased muscle tone. These forces could otherwise lead to:
- Client injury
- Loss of client position
- Equipment breakage
- Decreased sitting tolerance
- Increased agitation
- Decreased function
- Further increase in active extension
- Energy consumption
Dynamic backs move in response to extension at the hips. If the client is pushing against the footplates, extension will also occur at the hips. Energy is stored in the dynamic component (for example, an elastomer) which then returns the client to an upright posture. The Seating Dynamics Dynamic Rocker Back interface is designed with the pivot point is as close to possible as the natural pivot point of the hip joint. This ensures that the pelvis return to a neutral starting position after extension.
Dynamic Footrests respond to forces in 3 different planes. First, a telescoping movement downward diffuses forces, even if the knee does not extend (such as in people with very tight hamstrings). Second, the knee joint extends in combination with the telescoping movement to match the arc of the knee during extension. Finally, plantar and dorsi flexion are accommodated. The Dynamic Footrests are often used in combination with the Dynamic Back to diffuse force at the hips, knees, and even ankles. Design is critical to ensure ready movement as well as a return to a neutral starting position.
Dynamic Head Support Hardware
Some people with increased tone tend to extend with force at the neck, leading to loss of alignment of the head support or even breakage. If the client contacts the head pads with force, injury can even occur. Dynamic Head Support Hardware absorbs and diffuses these forces to protect both the client and the hardware. This solution is often used in combination with a Dynamic Back and Dynamic Footrests when extension is seen throughout the body.
Dynamic Seating is an important part of a wheelchair seating solution for people with increased muscle tone. We would love to hear your experiences! Just leave a comment or question below!