Year, Volume, Issue, Page(s):14, 1, 95, 43112
Study identified predictors of shoulder joint pain in people with paraplegia who used a manual wheelchair for at least 50 percent of their mobility and were asymptomatic for shoulder pain at study entry. Participants were classi?ed as having developed shoulder pain if they experienced an increase of 10 points on the Wheelchair User’s Shoulder Pain Index in the 3-year follow-up period. Measurements of maximal isometric shoulder torques were collected at study entry (baseline), 18 months, and 3 years. Daily activity was measured using a wheelchair odometer, and self-reported daily transfer and raise frequency data were collected by telephone every 6 weeks. Of the 223 participants enrolled in the study; 39.8 percent developed shoulder pain over the 3-year follow-up period. Demographic variables and higher activity levels were not associated with shoulder pain onset. Baseline maximal isometric torque (normalized by body weight) in all shoulder muscle groups was 10 to 15 percent lower in participants who developed shoulder pain compared with those who remained pain-free. Lower shoulder adduction torque was a signi?cant predictor of shoulder pain development, but the model explained only 7.5 percent of shoulder pain onset and consequently is of limited clinical utility. Overall, the results indicated that participants who developed shoulder pain had decreased muscle strength, particularly in the shoulder adductors, and lower levels of physical activity prior to the onset of shoulder pain. Neither factor was a strong predictor of shoulder pain onset.