The purpose of this study was to clarify the clinical and MRI features of irreparable massive rotator cuff tears (MT). Forty-eight patients (27 men, 21 women, average age 68.3yrs) who had been repaired with their MT(over two tendon or 5cm < width) were investigated. Patients were divided into three groups. They were E group (repair easily: 20 cases), SD group (slight difficult; 12 cases), D group (difficult; 16 cases). The differences among the three groups were tested for statistical significance examinations about age, sex, occupation (hard labor), existence of subscapularis (SSC) tendon tear, joint contracture, pre-operative JOAscore, MRI findings (position of cuff stump, fatty degeneration. The fatty degeneration was evaluated according to Goutallier's staging in oblique sagittal plane. Post-operative JOAscores were also investigated. The mean follow-up period was 25.1 months. Statistical study was done using Student's t-test, Kruskal-Wallis test, and χ2 test. The statistical differences between D group and other groups in the numbers of hard labors and SSC tendon tears was founded. We found the tendency that the age of D group was younger than other groups. In D group there were many cases in which cuff stump existed at the medial side of the joint surface and severe fatty degeneration of SSP and ISP were seen in MRI. JOA score improved in all groups (E; 57.6→92.2, SD 56.8→88.7, D; 52.4→86.3). The position of cuff stump (medial to glenoid) and fatty degeneration of ISP muscle in MRI seemed to be useful for expectation of irreparable cuff tears. The clinical features of irreparable MT were the number of hard labors and the existence of SSC tendon tear. The average age of the irreparable MT group was younger than that of the reparable groups.
