Rotator Cuff Tendon Pathology Progression Over 2 Years In Manual Wheelchair Users With Spinal Cord Injury

INTRODUCTION: Manual wheelchair (MWC) users with spinal cord injury (SCI) are at greater risk of developing shoulder pathology than their able-bodied (AB) counterparts. To address this health concern and develop targeted interventions, a more detailed understanding of temporal progression of shoulder pathology is necessary. PURPOSE To investigate the natural progression of rotator cuff tendon pathology over 2 years in MWC users and able-bodied (AB) age- and sex-matched individuals. METHODS Under Mayo Clinic IRB approval, the study enrolled 37 MWC users and 44 AB. The sample included 59 shoulders in MWC users (36 Dominant, 23 Nondominant) and 63 shoulders in AB (44 Dominant,19 Nondominant). The group comprised of 62 males, and 19 females with a mean avg of 41 yrs (SD = 12) at baseline. Bilateral shoulder MRIs were performed ~2 years apart. A musculoskeletal radiologist graded the rotator cuff tendon pathology progressions (tendinopathy and tears) across the two time points using the tendon pathology score (Jahanian et al., 2023). A bivariate analysis was used to test group differences and the effects of age, sex, arm dominance, and time since SCI (TSI) on pathology progression. TSI was categorized as: New (1-5 yrs), Mid (5-10 yrs), and Chronic (10+ yrs). RESULTS: The MWC group average pathology progression score (1.864) was higher than the AB group (0.476) (p = 0.002). A higher pathology score indicates worsening of pathology over the two-year timespan examined. Age, sex, and arm dominance were not significant predictors of shoulder progression pathology. However, in MWC users the dominant arm displayed a higher average progression score (2.25) compared to nondominant arm (1.435). A significant difference in progression scores was observed at TSI (p = 0.016). Chronic MWC users had higher average progression scores (2.091), followed by Mid (1.917), and New (1.640). CONCLUSION: Unsurprisingly, The MWC users had higher progression scores than the AB cohort. Similarly, Chronic MWC users had the highest progressions scores compared to other TSI categories. To gain a better understanding of these results, future studies will extend these analyses over longer periods. This longitudinal approach will allow for further examination on the clinical impact associated with risk factors and progression scores in MWC users. Supported by: NIH R01HD084423