Stand-Up Wheelchair for Severely Handicapped Children
D. A. Hobson J. Legal
Aprototype of a special chair for children with severe lower-limb involvement has been developed over a period of about two years. The immediate purpose of the special chair is to permit children whose lower limbs are either totally or partially involved to elevate themselves from a sitting to a standing position; and be mobile in both situations. In general, these children are not candidates for walking habilitation, and would normally spend most of the day in a standard wheelchair. Specifically, children with spina bifida, muscular dystrophy, or arthrogryposis are the main candidates for a chair of this type.
There are several sound reasons why it is desirable for handicapped children to assume the upright position at a young age. Weight-bearing through the skeletal structures of the lower limbs is a factor which encourages normal bone growth. Increased mobility combined with standing is likely to encourage normal kidney function. Periodic standing causes the joints of the lower limb to pass through their normal ranges of motion, thereby reducing the likelihood of permanent joint contractures which can result from prolonged sitting. Lastly, there seems to be definite psychological advantages to be gained if a handicapped child is permitted to assume the upright position at approximately the normal age.
The stand-up chair has been designed to encourage the child to assume the upright position as often as possible. The chair is mounted on an easily manoeuverable wheeled frame which provides the child with mobility in both the seated and standing positions. The elevating mechanism consists of a four-bar linkage system which causes the seat, footrest, and back to move in close approximation to the movements of the body segments in the transition from sitting to standing. The back and leg supports are tiltable, as in a "Lazy Boy" chair, so that children can assume the semireclined position if resting periods are necessary.
The prototype model is at present undergoing evaluation by a local ten-year-old girl with muscular dystrophy of the Wernig-Hoffman type ( Figs. 1 and 2 ). The present model was made to accommodate a child of about ten years of age, and it is anticipated that most children could be accommodated with three sizes. It also seems possible that a select group of adult patients could benefit from a larger version of the stand-up wheelchair.
Further developments will be necessary in order to make the chair more versatile for outdoor uses. About four more chairs of various sizes, complete with design changes, will be made under the evaluation program of the Winnipeg Shriners Hospital. After that time efforts will be made to interest a manufacturer in making the stand-up chair available to a larger number of children with similar disabilities.