In Vivo Biomechanical Assessment of a Novel Handle-Based Wheelchair Drive

Abstract

Push-rim wheelchair propulsion frequently causes severe upper limb injuries in people relying on the wheelchair for ambulation. To address this problem, we developed a novel handle-based wheelchair propulsion method that follows a cyclic motion within ergonomic joint ranges of motion. The aim of this study was to measure hand propulsion forces, joint excursions and net joint torques for this novel propulsion device and to compare its performance against traditional push-rim wheelchair propulsion. We hypothesized that under similar conditions, joint excursions of this novel handle-based device will remain within their ergonomic range and that the effectiveness of the propulsion forces will be higher, leading to lower average propulsion forces compared to push-rim propulsion and reducing the risk of injury.Eight paraplegic subjects propelled the new device at two different loads on a custom-made wheelchair-based test rig. Video motion capture and force sensors were used to monitor shoulder and wrist joint kinematics and kinetics. Shoulder and wrist loads were calculated using a modified upper-extremity Wheelchair Propulsion Model available in OpenSim.The results show that with this novel propulsion device joint excursions are within their recommended ergonomic ranges, resulting in a reduced range of motion of up to 30% at the shoulder and up to 80% at the wrist, while average resultant peak forces were reduced by up to 20% compared to push-rim propulsion. Furthermore, the lower net torques at both the shoulder and wrist demonstrate the potential of this novel propulsion system to reduce the risk of upper-extremity injuries.

Upper limb modeling and motion extraction based on multi-space-fusion

“… EL is a rotary joint 47 , 62 with one DOF rotating around the Z -axes (the composite joint structure contributes significantly to the stability of forearm motion). WR is a rotary joint 47 , 63 with two DOFs rotating around the X - and Z -axes (the composite joint structure contributes significantly to the sophisticated motions and stability of the palm). The clavicle is horizontal (parallel to the X–Z plane) when the arm is in its natural downward state.…”

“…WR is a rotary joint 47 , 63 with two DOFs rotating around the X - and Z -axes (the composite joint structure contributes significantly to the sophisticated motions and stability of the palm).…”

Metabolic Cost and Mechanical Efficiency of a Novel Handle-Based Device for Wheelchair Propulsion

“…Moreover, the current findings indicate that propelling a wheelchair with this novel HBP device is more efficient and less strenuous than propelling a wheelchair with a pushrim. In addition, our previous study (23) showed that the HBP device may lower the probability of upper limb injuries by reducing joint loads and ergonomic joint ranges. To adapt to an individual user's wheelchair, the horizontal and vertical adjustment mechanisms shown in Fig.…”

“…Our group has developed a novel handle-based propulsion (HBP) mechanism for conventional wheelchairs as a compact indoor alternative to PRP (21). With an ergonomically optimized propulsion movement and the ability to continuously apply propulsive force, HBP offers a continuous cyclic motion at ergonomic joint ranges of motion and has been shown to decrease joint excursions and maximum joint torques during propulsion (21)(22)(23). The aim of the current study was to investigate differences in metabolic cost and mechanical efficiency for this novel HBP device compared with the standard PRP.…”