Progression of symptomatic bilateral rotator cuff disease.

Background: Prior studies have demonstrated that conservatively treated rotator cuff tears and rotator cuff tendinopathy may continue to progress. It is unclear whether that rate of progression differs between sides in patients with bilateral disease. This study evaluated the likelihood of progression of rotator cuff disease as confirmed via magnetic resonance imaging (MRI) in individuals with symptomatic bilateral pathology, treated conservatively for a minimum of 1 year. Methods: We identified patients with bilateral rotator cuff disease confirmed via MRI within the Veteran's Health Administration electronic database. A retrospective chart review via the Veteran's Affairs electronic medical record was performed. Progression was determined using 2 separate MRIs with a minimum of 1 year apart. We defined progression as (1) a progression from tendinopathy to tearing, (2) an increase from partial-thickness to full-thickness tearing, or (3) an increase in tear retraction or tear width of at least 5 mm. Results: Four hundred eighty MRI studies from 120 Veteran's Affair patients with bilateral, conservatively treated rotator cuff disease were evaluated. Overall, 42% (100/240) of rotator cuff disease had progressed. No significant difference was found between progression of right vs. left rotator cuff pathology, with right shoulder pathology progressing at a rate of 39% (47/120), while left shoulder disease progressed at a rate of 44% (53/120). The likelihood of disease progression was associated with less initial tendon retraction (P value = .016) and older age (P value = .025). Conclusions: Rotator cuff tears are no more likely to progress on the right, as compared to the left side. Older age and less initial tendon retraction were found to be predictors of disease progression. These suggest that higher activity level may not associate with greater progression of rotator cuff disease. Future prospective studies evaluating progression rates between dominant vs. nondominant shoulders are warranted.