The purpose of this study was to investigate the changes of MRI findings and JOA score of the patients with rotator cuff tear after open tenorraphy. Operated on 28 cases with rotator cuff tear were performed operation and underwent MRI of the shoulder at from 6 to 12 months (short-term group)and at over 13 months (long-term group) after the operation at the Shizuoka Red Cross Hospital from February 2002 to June 2003. Anterior acromioplasty and open tenorraphy were performed mainly using McLaughlin's method by modified Mason-Allen suture. MRI (T2 with fat suppression) findings were classified according to Sugaya's classification(Type I-V). The thickness of the rotator cuff and fat layer were evaluated according to Murals method. Clinical outcome was evaluated by JOA score. In Sugaya's classification,7 cases improved with the grade from Type II to Typel but 1 case worsened from Type II to Type III. Overall the re-tear rate(Types N, V ) was 27.3% and could be confirmed by short-term MRI. In the complete-thickness tear group, the re-tear rate was 12.5% in SSP tendon tear alone and 66.7% in the massive tear group(p<0.05). The re-tear rate of complete-thickness tear with concomitant tear of LHB or SSc tendon was 83.3%, but the re-tear rate of the rest was 6.3%. In the healed group(Type I, II, III ), the JOA score improved significantly from 67.0 preoperatively to 95.4 postoperatively, and in the re-tear group, from 60.1 to 89.8(p<0.05). The preoperative risk factors of re-tear were a massive tear and concomitance of the LHB or SSc lesions. The re-tear rate of a complete-thickness tear was 27.3%, and a re-tear occurred shortly after the operation.
