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Tilt-in-space and Recline Wheelchairs
Definition and Explanation
Tilt-in-space refers to changing the orientation of one sitting in a wheelchair, but keeping the hip, knee, and ankle angles the same. A recline wheelchair allows change to the seat-to-back angle, as well as the lower extremity joint angles using the leg rests. Tilt-in-space and recline wheelchairs can combine both features or be found separately. Either one can be incorporated with a power chair and numerous other assistive wheelchair features. Tilt-in-space wheelchairs often offer 45 degrees of tilt, but some can go as far as 55 degrees. Recline chairs change the seat-to-back angle up to 180 degrees.
Goals of Both Systems
Both systems have the goal of redistributing pressures or loads on the body, particularly on the ischial tuberosities and coccyx or the distal/caudal pelvic bones that humans commonly sit on. Some of the other benefits that both systems supply are: • Increase blood flow or regulate blood pressure • Head and trunk control • Positioning for function or ease of transfers • Aid with sleeping and resting • Improve feeding • Improve respiration • Adjust the field of vision • Minimize muscle tone (spasticity)
Persons with conditions such as cerebral palsy (CP), spinal cord injury (SCI), muscle diseases, head injuries, or those who cannot actively reposition themselves are the beneficiaries of such systems. However, not all features are recommended for all populations of people.
Tilt-in-space devices are prescribed more for patients with the conditions including CP and pediatric patients with SCI, that leave patients with spacticity or limited range of motion (ROM). Spastic muscle responses are often muscle reflexes that due to injury can not be regulated by the body in a normal way, and are often activated by any kind of movement or stretch. When repositioning patients with this condition changing joint angles can cause this unwanted muscle activation. Additionally, ROM may be inhibited by muscle contractures or stiffened joints. Both situations require that the lower extremities maintain their positioning.
The tilt system provides additional benefits over recline wheelchairs. One of these is maintaining posture, that would be lost in a recline system, requiring that the person be removed from the chair and reseated. Posture maintenance is important for pediatric patients who are more at risk of developing scoliosis. Tilt chairs can also be set to provide access to other tools and utilities on a persons wheelchair, such as communication devices and chair controls, at all times. These other items often tilt with the user in the chair.
Conversely, tilt can limit patients who use a desk or other furniture that could be harmful if the person tilted without first pulling away from the item. They offer limited access in these situations because they will not often fit underneath while tilted. Fixed hip position can also keep the bladder constricted, which is not indicated for persons experiencing urination problems and catheterization. Items on a lap-top tray or one connected the wheelchair can fall during tilting and a tilted position can make transfers more difficult.
Recline systems offer better distribution of weight or load by decreasing the seat-to-back angle of a wheelchair. They also position the patient for easier transfers, passive stretch or ROM, bowel and bladder function, and will not effect set up of trays or work space on the wheelchair.
Contraindications for both
Neither is recommended for persons who experience increased tone or muscle reflex activation in a supine position. Such activation can occur in persons with tonic labyrinthine regardless of hip position or angle.
Lange, M. L. (2000, June). Tilt in space versus recline--New trends in an old debate. Technology Special Interest Section quarterly, 10, 1-3. http://www.wheelchairnet.org/wcn_prodserv/Clinicians/Tilt_vs_recline.html