We sometimes experienced osteoarthritic (OA) change with cuff tear. However there are few reports about the prevalence, effect of cuff repair and effect on clinical results about OA change with cuff tear. The purpose of this study is to clarify these things by assessing the patients with cuff tear treated by surgery. We studied 234 shoulders, excluding 20 shoulders in which preoperative X-ray image showed OA change equivalent to Gerber's stage 3. We defined shoulders with progression of OA change referring Gerber's classification at 2 year after cuff repair as “Deteriorated group” and those with unchanging of OA change as “Unchanging group”. Inter-group differences were tested for statistical significance according to medical history, tear size and location, and clinical evaluations (range of motion, muscle strength, UCLA score). Deteriorated group included 39 shoulders (17%) and Unchanging group include 195 shoulders (83%). No significant differences were found in medical history between groups. The size of cuff tear in the Deteriorated group was larger than in the Unchanging group ( P<0.05 ). Regarding the location of the tear, there were more tears at the infraspinatus and teres minor tendon in the deteriorated group significantly ( P<0.05 ). Muscle strength and range of motion toward external rotation at first position before surgery were lower in the Deteriorated group ( P<0.05 ). No significant differences were found in UCLA score before surgery. There are no significant differences in clinical evaluations at 2 years after surgery. The causes of progression of OA change after cuff repair were larger tear size and if the tear progressed to the posterior. However, it is supposed that the progression of OA change doesn't affect postoperative clinical results.
