Abstract
We report two cases of posterior shoulder instability due to playing baseball.
Case 1 : A 16-year-old boy experienced pain in the right shoulder when throwing a ball sidearm, in spite of usually pitching overhand. After the injury, he frequently felt shoulder pain during pitching. Jerk test demonstrated instability of the right shoulder. At six months after the injury, surgery was performed. Posterior capsular elongation was evident, and we performed arthroscopic capsulolabral plication without suture anchors. At three months after the operation, the patient was free of pain, and the jerk test gave a slightly positive result. Case 2 : An 18-year-old male felt left pain when swinging a bat during baseball practice. After the injury, he frequently felt pain during pitching and in daily life. Jerk test demonstrated instability of the left shoulder. At 4 years after the injury, surgery was performed, and this revealed a labral lesion in the posterior portion of the glenoid with posterior capsular elongation. We performed arthroscopic capsulolabral repair with suture anchors. At one year after the operation, the patient was free of pain during pitching and in daily life. Jerk test gave a negative result. These cases demonstrate that arthroscopic posterior capsulolabral plication and repair are useful for treatment of posterior shoulder instability.
