A standard wheelchair is a mobility device designed primarily for manual propulsion using the user’s upper body strength. The hemi height wheelchair is a specialized variation created to accommodate a different method of self-propulsion. The term “hemi height” refers to a lower seat-to-floor distance than found on a typical adult chair. This modification enables greater independence for individuals with specific physical limitations.
The Defining Measurement
The fundamental characteristic of a hemi height wheelchair is its reduced seat-to-floor measurement. A typical adult wheelchair seat height ranges from 19.5 to 20.5 inches. In contrast, the hemi height chair lowers this distance, often to a range of 17.5 inches or sometimes down to 16 inches.
This measurement establishes the clearance needed for the lower extremities to reach the floor comfortably. Achieving this lower height often involves using a dual axle position on the frame, allowing the rear wheel axle to be repositioned lower. Some designs also incorporate smaller diameter rear wheels (20-inch or 22-inch) and smaller front casters, instead of the standard 24-inch wheels, to reduce the overall frame height.
Facilitating Independent Movement
The lower seat height enables a user to propel the chair using their feet and legs, a method known as foot propelling. The reduced distance ensures the user’s feet are placed firmly on the ground while maintaining proper hip and knee positioning. This secure foot contact allows the user to push off the floor, generating movement, steering, and braking power. Foot propulsion is often a more efficient method, utilizing larger muscle groups in the legs. This technique can reduce the physical strain and risk of repetitive strain injury to the shoulders and arms, a common concern with traditional hand-rim propulsion.
Who Benefits from a Hemi Height Design
The hemi height design is tailored for individuals who retain functional strength in one or both legs but have limited upper body strength. A primary beneficiary group includes those recovering from a stroke, a condition often leading to hemiparesis (weakness affecting one side of the body). The “hemi” in the name references this population, as they can use their unaffected arm and stronger leg for propulsion. People with shorter stature also benefit, as the lowered design prevents their feet from dangling. The chair provides a viable alternative for independent mobility when full upper-body propulsion is not feasible.
Key Structural Differences
Beyond the lower seat-to-floor height, the hemi height design requires specific structural adjustments for safety and function. The rear wheel axle position is often relocated lower down the frame to achieve the reduced seat height, which also affects stability. Some models feature a dual axle plate, allowing the user to select the appropriate height setting during setup.
To prevent interference with foot propelling, hemi height wheelchairs are configured with swing-away or removable footrests. This hardware allows the footplates to be moved out of the way, giving the user an unobstructed path to the floor. Additionally, since the seat surface is lower, the armrests are positioned at a reduced height to ensure the user’s elbows can rest comfortably without excessive shoulder elevation.