Comparison of tear characteristics, outcome parameters and healing in traumatic and non-traumatic rotator cuff tear: a prospective cohort study

Purpose: Acute traumatic and chronic non-traumatic rotator cuff tears are etiologically distinguishable entities. However, prospective studies comparing tear characteristics and outcomes between these two types of tears are lacking. The purpose of this study was to compare the tear characteristics, clinical and functional outcomes, and tendon healing as assessed on magnetic resonance imaging (MRI), between traumatic and non-traumatic rotator cuff tears. Methods: MRI proven rotator cuff tears were allocated into two groups according to the history of injury: Group 1 included 28 patients with traumatic tears and group 2 included 33 patients of non-traumatic cuff tears. Both the groups were compared for preoperative tear characteristics (tear size, muscle atrophy, fatty degeneration), range of motion, strength of shoulder abduction and external rotation, functional outcomes, and tendon integrity on MRI, 2 years after the surgery. Results: Postoperative mean active range of abduction (p = 0.005), abduction strength (p = 0.013), external rotation strength (p = 0.027), University of California at Los Angeles score (p < 0.001), Constant score (p = 0.002), American Shoulder and Elbow Surgeons scores (p = 0.028) and visual analog scale for pain (p = 0.02) were significantly better in group 1 as compared to group 2. The postoperative structural integrity of the cuff on MRI was better in group 1 as compared to group 2, but the values did not reach statistical significance (p = 0.13). Conclusion: Findings from this study suggest that traumatic tears affect younger patients and while having a larger tear size, they have lesser muscle atrophy, fatty degeneration, and tendon retraction. Functional outcomes are better after treatment of traumatic tears as compared to non-traumatic tears. Chronicity of the tear and tendon retraction negatively affected healing in traumatic cuff tears. Muscle atrophy was found to be associated with poorer healing in non-traumatic tears. However, tear size was not associated with healing. Level of evidence: II, Prospective cohort study. © 2021, Istituto Ortopedico Rizzoli.