Important Parameters of Wheelchairs
A wheelchair is one of the commonly used assistive mobility tools. By using a wheelchair, it can help users complete activities of daily living and do what they want to do as independently as possible. At the same time, wheelchairs can also improve the functional level of users in many ways. Proper use of wheelchairs can prevent pressure sores and problems caused by poor sitting posture. A suitable wheelchair is not only an assistive device for the disabled, but also a means to make users more confident and able to participate in social life more actively and equally.
Measurement and determination of wheelchair parameters
The size of the various parts of the wheelchair is closely related to the user's risk of pressure ulcers and the way the wheelchair is driven. It is especially important to understand the appropriate wheelchair parameter adjustment.
a. seat height; b. seat width; c. seat length; d. armrest height; e. backrest height
Seat height.
The wheelchair user sits on a chair with the knees flexed at 90° and the feet are on the ground. Measure the distance from the popliteal fossa (popliteal fossa, that is, the depression at the junction of the thigh and calf on the flexed side of the knee joint) to the ground minus the height of the seat cushion Add another 5 cm. If you don't need a cushion, you don't need to subtract the cushion height. If the seat of the wheelchair is too low, the pressure on the ischial tuberosity will be too high, which will lead to pressure sores; if the seat is too high, the legs will hang in the air, making it difficult to maintain balance.
Seat width.
When measuring, the user needs to sit on the seat and measure the distance between the widest parts of the two buttocks. This distance plus 5 cm (about the distance of two fingers on each side) is the seat width.
Seat length.
Measure the horizontal distance from the rear buttocks to the popliteal fossa when sitting down, and subtract 3~6cm from the measurement result to get the seat length. If the seat is too short, the weight mainly falls on the ischia, and the local area is prone to excessive pressure; if the seat is too long, it will compress the popliteal fossa, affect local blood circulation, and easily irritate the skin. For users with hip and knee flexion contractures, use short Seats are good.
Armrest height.
When sitting down, the upper arm is vertical, the forearm is placed flat on the armrest, and the height from the chair surface to the lower edge of the forearm is measured, plus 2.5cm. Proper armrest height helps maintain proper body posture and balance, and allows the upper body to be placed in a comfortable position.
Backrest height.
The height of the high back is the actual height from the seat to the shoulder and neck. The height of the ordinary backrest is the height from the lower angle of the shoulder blade to the seat. The height of the low backrest is the height from the lower end of the chest to the seat, or the distance from the seat to the armpits minus 10 cm, which is conducive to the activities of the upper limbs of the user, so that the shoulders have enough space to drive the wheelchair. Under the premise of ensuring safety, the lower the backrest height, the better.
Wheelchair Options
Different diseases and injuries have different needs for wheelchairs.
For patients with hemiplegia, those who can maintain balance in the sitting position without supervision and protection can choose a standard wheelchair with a low seat, and the foot rest and leg rest can be detachable, so that the leg of the healthy side can fully touch the ground, and the upper and lower limbs of the healthy side can be used for manipulation wheelchair. Those with poor balance function or cognitive impairment should choose a wheelchair pushed by others, and those who need the help of others to transfer should choose detachable armrests.
For patients with lower limb amputations, especially those with bilateral thigh amputations, the center of gravity of the body has changed a lot. Generally, the axle should be moved backward and an anti-dumping bar should be installed to prevent the user from falling backwards. If prosthetics are present, leg and foot rests should also be fitted.
For patients with quadriplegia, those with C4 (C4, the fourth segment of the cervical cord) and above injuries can choose air-controlled or chin-controlled electric wheelchairs or wheelchairs pushed by others. People with injuries below C 5 (C 5, that is, the fifth segment of the cervical spinal cord) can rely on the strength of upper limb flexion to operate the horizontal handle, so a high-back wheelchair controlled by the forearm can be selected. Special attention should be paid to the fact that patients with orthostatic hypotension should choose a reclinable high-back wheelchair with a headrest installed; in addition, a removable footrest with adjustable knee angle should be selected.
Paraplegics have basically the same needs for wheelchairs, and the specifications of the seats are determined by the measurement methods mentioned above. Generally, step-type short handrails are selected and caster locks are installed. Those with ankle spasticity or clonus need to add ankle straps and heel rings. Solid tires can be used when the road conditions in the living environment are good.
