Michelle L. Lange, OTR/L, ABDA, ATP/SMS
Our past two blogs have addressed clinical benefits of Dynamic Seating, specifically the evidence for Dynamic Seating improving Postural Control and Function. Several of our past blogs have addressed using Dynamic Seating to prevent client injury, typically by exploring specific case studies. In this blog, we will take a look at the evidence for this clinical benefit.
Extension forces can lead to pain and, as a result, decrease sitting tolerance (Cimolin, et al., 2009; Crane, et al., 2007; Incoronato, 2007). Movement has been shown to decrease pain in wheelchair users (Lyons, et al., 2017; Frank & DeSouza, 2017). Dynamic seating provides movement and has been shown to decrease pain (Cimolin, et al., 2009, Crane, et al., 2007; Incoronato, 2006; Watson, et al., 1998).
Joint and Bone Injuries
The forces from this extension on the client’s body can lead to injury (Hong, 2006). Extension causes tremendous force through joints and can even lead to joint damage and bone fractures.
Concussions and Neck Injuries
Repeated and strong impacts between the head and the head support could even lead to concussions. A concussion can occur when the head collides with force against a surface. Some clients using wheelchairs bang against the head pad with significant force, perhaps even enough force to cause brain injury. Degree of force and repetitive impacts only increase risk of injury. Dynamic components absorb force, reducing this risk. Clients who extend against a head support with sustained force are also at risk of neck injury (including strains) due to forces occurring through the soft tissue and vertebrae of the neck.
Decreased upper extremity dystonic movement found by Avellis, et al, 2010 and Cimolin, et al., 2009, could reduce injury caused by large and uncontrolled upper extremity movements.
Shear forces can occur as the client extends against a static surface, which increases the risk of skin and tissue injury (Avellis, et al, 2010; Cimolin, et al., 2009; Crane, et al., 2007; Dawley & Julian, 2003). Dynamic Seating can reduce shear forces, as the seating surfaces move with the client, maintaining improved contact (Lange, et al., 2017).
Preventing Tipping Related Injuries
Many clients with intellectual disabilities tend to move a lot and frequently rock in their wheelchair seating system. This rocking movement may be so strong as to literally “bounce” a manual wheelchair across the room and can lead to the wheelchair tipping over and causing client injury. Dynamic seating moves in response to this rocking movement, which may reduce the risk of tipping the wheelchair over. In a 1997 study by Gaal et al., wheelchair “tips and falls” were the most commonly found wheelchair incidents, followed closely by component failures (Gaal et al., 1997). While this study did not isolate wheelchair incidents in any single population of wheelchair users, it highlights this as one of the main potential causes of wheelchair rider injuries.
So, what’s the bottom line? Dynamic Seating can reduce the risk of client injuries, an extremely important clinical benefit!
Please refer to our Literature Review which includes all the references cited here.