Effects of a trained mobility assistance dog on upper extremity muscular effort during wheelchair propulsion on tiled and carpeted floors in individuals with a spinal cord injury

Background: Many manual wheelchair users with a spinal cord injury are at risk of developing secondary upper extremity musculoskeletal impairments. The use of a mobility assistance dog may represent a way to mitigate this risk. This study aims to compare upper extremity muscular effort in this population when propelling a manual wheelchair on tiled and carpeted surfaces with and without the assistance of a dog. Method: Thirteen adults with a spinal cord injury propelled their manual wheelchairs at a self-selected natural speed over a 10-meter distance on tiled abrasive and carpeted floors with and without their mobility assistance dog. Surface electromyography of the pectoralis major, anterior deltoid, biceps, and triceps was recorded and normalized against its maximal value extracted from maximal voluntary contractions. Time needed to perform each task was also computed. Findings: The forward pull provided by the dog significantly and meaningfully reduced the muscular effort when propelling on the tiled floor and, even more so, on carpeted surfaces for the pectoralis major (- 27.0% and - 59.2%), the anterior deltoid (- 54.8% and - 92.4%), the biceps (- 53.9% and - 57.6%), and the triceps (- 45.7% and -67.3%). The time needed to travel the 10-meter distance was also significantly and meaningfully reduced on the tiled and carpeted surfaces (- 21.9% and - 30.3%, respectively). Interpretation: The provision of a mobility assistance dog represents a viable rehabilitation alternative to minimizing upper extremity muscular effort while also optimizing speed during propulsion in manual wheelchair users with a spinal cord injury.