The Evaluation of Supraspinatus Muscle of Patients with Rotator Cuff Tear on Magnetic Resonance Imaging

We examined the intensity of the supraspinetus muscles of patients with a rotator cuff tear in Magnetic Resonance Imaging (MRI) findings. 109 shoulders in patients with rotator cuff tears were preoperatively scanned by MRIs. Using MRIs, the linear bands of the supraspinatus muscle were classified into three grades. Between each grade the following were examined; the age, the disease contraction period, the distribution of large tears and reruptures, and those chosen for patch graft method, as well as the postoperative JOA scores. There were 46 cases in grade 1(G-1), 28 in grade 2(G-2), and 35 in grade 3(G-3). The mean ages of patients in the three grades were 53.4 years old, 56.7 years old, 61.3 years old respectively. The age of G-3 was significantly higher than the other grades. The period from onset of the G-3 was shorter than the other grades, but there was no statistic significance. The ratio of massive tears were 2.2%, 27.0% and 46.2% respectively. Reruptures were observed only in grade 3 and there were none in G-2. and G-3. The patch graft method was performed on one shoulder in G-2 and three shoulders in G-3. The average JOA scores were 89.5 in G-1, 88.4 in G-2 and 85.0 in G-3. The JOA score of G-3 was significantly lower than G-1. Especially function of JOA score was lower than the other grades. The results of the present study suggest that high intensity on MRI is associated with poor clinical results in operative treatment. Some authers reports that these findings of MRI demonstrate a fatty degeneration of muscles. So we should select the best operation and carefuly rehabilitate patients with a high intensity of the supraspinatus muscle belly on MRI