Factors associated with pseudoparalysis in patients with extensive chronic and atraumatic rotator cuff injury

Background: Patients with massive chronic atraumatic rotator cuff injuries can be asymptomatic or present severe shoulder dysfunction, a condition known as pseudoparalysis. Our hypothesis is that integrity of the subscapularis, hypertrophy of the teres minor, and a complete tear of the long head of the biceps tendon are associated with improved active forward flexion range in such patients. Therefore, the objective of this study was to evaluate factors associated with pseudoparalysis.

Methods: This was a single-center cross-sectional study that included patients with massive chronic atraumatic rotator cuff injuries. Range of motion of the affected shoulder, demographic data, specific tests for rotator cuff assessment, and imaging studies were collected.

Results: A total of 68 patients (71 shoulders) were included in the study. At initial evaluation, 41 patients exhibited active forward flexion of the shoulder greater than 90° (No Pseudoparalysis group). Patients with active forward flexion less than 90° (n = 29) underwent subacromial injection of local anesthetic and were then reevaluated. In 15 patients the pseudoparalysis was resolved (False Pseudoparalysis group), and 14 maintained active forward flexion of less than 90° (True Pseudoparalysis group).

Conclusion: We concluded that the presence of a shoulder shrug sign, Goutallier grade III and IV fatty infiltration, and a full-thickness tear of the subscapularis were risk factors for the occurrence of pseudoparalysis. Tear extension, as described by Wieser et al, also demonstrated statistical difference between groups, with greater anterior tear extension (involvement of subscapularis tendon) and greater global tear extension observed in the True Pseudoparalysis group.