Wheelchair Fit

How to Measure for Wheelchair Seating

It is important to have a wheelchair that fits appropriately. If a wheelchair is the wrong size, it can lead to issues with posture, muscle and joint quality, breathing, blood circulation, and overall comfort. These can cause secondary problems making treatment and therapy more complicated. There are five main measurements to take for proper wheelchair seating.

1. Seat Width: Measure from the widest part of the thighs or hips. Add 2.5 – 5 cm. The extra space helps provide room when transferring to another surface, allows for repositioning, and decreases rubbing and pressure. However, if the seat is too wide, the person may start leaning to the side or sticking their arms out to push the wheels.
2. Seat Depth: Measure from the bottom of the back to behind the knee. Subtract 2.5 – 5 cm from the measurement so the edge of the wheelchair does not rub the back of the knee and restrict motion or circulation. Measure both legs in case they are different lengths.
3. Seat Height: Measure from the back of the knee to the bottom of the heel. Footrests should have 5 cm space from the floor. The thighs should be parallel to the floor. A seat cushion can also raise the seat height.
4. Seat-Back Height: Measure from the wheelchair seat (including cushion) to the
   top of the shoulder. If there is poor upper body control, a higher back height might be necessary. If the seat height is too low, there is less stability and the individual will not have enough back support. If the seatback height is too high, they will have difficulty pushing the wheels themselves.
5. Armrest Height: Measure from the wheelchair seat (including cushion) to the bottom of the flexed (bent) elbow. Armrest should be about 1.5 cm higher. This helps to support the arms, provide a place to push from for transfers or pressure release, and aligns posture. If the armrest is too low, the individual will lean to one side. If the armrest is too high, it raises the shoulders. 

References:

Dudgeon, B., Deitz, J., & Dimpfel, M. (2014). Wheelchair Selection. In M. Radomski & C. Trombly (7th Ed.), Occupational therapy for physical dysfunction (pp.485-579). Baltimore, MD: Lippincott Williams & Wilkins.