Upper-extremity torque production in men with paraplegia who use wheelchairs

Objectives: To study maximal upper-extremity torque values and agonist/antagonist torque ratios in a sample of individuals with paraplegia and to compare these values with a sample of age-, gender-, and weight-matched able-bodied individuals. Design: Cross-sectional, case-control study. Setting: A biomechanics laboratory. Participants: A convenience sample of 15 men with complete (American Spinal Injury Association class A) T5-L2 paraplegia and 15 able-bodied control subjects. Interventions: Not applicable. Main Outcome Measures: Maximal isometric torques of 12 upper-extremity muscle groups (shoulder, elbow, and wrist flexion and extension; shoulder abduction and adduction; shoulder internal and external rotation; elbow pronation and supination) were measured with custom dynamometers. Results: Maximal torque values and agonist/antagonist torque ratios for the shoulder, elbow, and wrist functions did not differ between the control subjects and those with complete paraplegia, with the exception of the supination/pronation torque ratio, which was significantly higher in the able-bodied control group. Conclusion: Wheelchair propulsion and other functional activities, such as transfers, do not significantly affect maximum torque production of the upper extremities in individuals with paraplegia. On the basis of these findings, arguments that upper-extremity muscle imbalances are important contributory factors to upper-extremity pain and dysfunction in this group may be too simplistic.