Progression of rotator cuff tendon pathology in manual wheelchair users with spinal cord injury: A 1-year longitudinal study

Objective: To investigate the progression of rotator cuff tendon pathology across one year in manual wheelchair (MWC) users with spinal cord injury (SCI) and matched able-bodied individuals, and to explore the association between pain, age, and duration of wheelchair use with the progression of rotator cuff pathology. Design: Longitudinal cohort study, 1-year follow-up. Setting: Outpatient clinic at a tertiary medical center. Participants: Twenty-four adult MWC users with SCI (20 men) with an average age (SD) of 37(12) years and 24 age and sex-matched able-bodied individuals. Interventions: Not applicable. Main outcome measure(s): Presence of shoulder pain was collected. Magnetic resonance imaging (MRI) abnormalities of rotator cuff tendons including tendinopathy and tendon tears at baseline and 1-year follow-up visits were graded by a board-certified musculoskeletal radiologist, and three categories of tendon pathology scores including individual tendon scores, unilateral cuff scores, and bilateral cuff scores were calculated for each participant. Results: Fifty-four percent of the MWC users reported shoulder pain at both time points which was significantly higher than able-bodied cohort at baseline (17%, P = 0.012) and year 1 (21%, P = 0.021). Rotator cuff tendon pathology was detected as mainly mild tendinopathies and low-grade partial-thickness tears in both cohorts at both time points but was more common in MWC users. The results for the bilateral cuff scores indicated a significant (P < 0.008) progression of rotator cuff tendon pathology in the MWC users over one year. MRI findings did not change significantly for the able-bodied cohort across time. There was no association of pain, age, or duration of MWC use with progression of rotator cuff pathology in MWC user cohort. Conclusion: MWC users had a higher prevalence of pain than matched able-bodied cohort, but pain was minimal and not function-limiting. Bilateral cuff TOTAL scores showed pathology progression in MWC users, but MRI findings remained stable in the able-bodied cohort. MWC users were 3.4 times more likely to experience pathology progression than the able-bodied cohort.