Abstract
Background: Repair of massive rotator cuff tear was often unsatisfactory and had a high rate of re-tear compared with small, medium and large tears. The purpose of this study was to investigate the factor of re-tear after repair for massive rotator cuff tears in preoperative MRI.
Methods: Twenty-three shoulders had ORCR or ARCR performed for massive rotator cuff tears. There were 16 shoulders in no re-tear group (group A) and 7 shoulders in re-tear group (group B). Superior migration of the humeral head (Oizumi classification), acromiohumeral interval (AHI), femoralization, rate of longitudinal length of supraspinatus muscle, distance of rotator cuff from glenoid, muscle atrophy (Occupation ratio), and fatty degeneration (Goutallier classification) were investigated.
Results: In superior migration of the humeral head, there were 6 shoulders in grade I, 10 shoulders in grade II, and no shoulder in grade III in group A, and 1 shoulder in grade I, 4 shoulders in grade II, and 2 shoulders in grade III in group B. AHI was 4.4mm in group A, and 4.9mm in group B. Femoralization was observed in 1 shoulder (6.3%) in group A, and 2 shoulders (28.6%) in group B. Rate of longitudinal length of supraspinatus muscle was 0.73 in group A and 0.64 in group B. The distance of rotator cuff from glenoid was 19.6mm in group A, and 18.5mm in group B. Muscle atrophy was 0.44 in group A, and 0.41 in group B. In fatty degeneration, 14 shoulders in grade II, 1 shoulder in grade III, 1shoulder in grade IV in group A, and 6 shoulders in grade II, 1 shoulder in grade III in group B.
Discussion: Femoralization and superior migration of the humeral head of Grade III which associated to obsolete superior migration of the humeral head were factors of re-tear after repair for massive rotator cuff tears.
