Shoulder Pain Is Associated With Rate of Rise and Jerk of the Applied Forces During Wheelchair Propulsion in Individuals With Paraplegic Spinal Cord Injury.

Objective: To investigate the association between propulsion biomechanics, including variables that describe smoothness of the applied forces, and shoulder pain in individuals with spinal cord injury (SCI).

Design: Cross-sectional, observational study.

Setting: Non-university research institution.

Participants: Community dwelling, wheelchair dependent participants (N=30) with chronic paraplegia between T2 and L1, with and without shoulder pain (age, 48.6±9.3y; 83% men).

Interventions: Not applicable.

Main Outcome Measures: Rate of rise and jerk of applied forces during wheelchair propulsion. Participants were stratified in groups with low, moderate, and high pain based on their Wheelchair User Shoulder Pain Index score on the day of measurement.

Results: A mixed-effect multilevel analysis showed that wheelchair users in the high pain group propelled with a significantly greater rate of rise and jerk, measures that describe smoothness of the applied forces, compared with individuals with less or no pain, when controlling for all covariables.

Conclusions: Individuals with severe shoulder pain propelled with less smooth strokes compared to individuals with less or no pain. This supports a possible association between shoulder pain and rate of rise and jerk of the applied forces during wheelchair propulsion.