Unstable painful shoulder (UPS) is defined as shoulder pain related to anteroinferior instability without any feeling of dislocation or subluxation. There are two clinical studies of UPS. These studies had some differences in the definition of UPS but had similar patient characteristics, namely an age in the twenties, high percentage of males, dominant arm, and high sports activity including collision and contact sports. Preoperative imaging and intraoperative findings revealed a high incidence of capsular labrum lesions including Bankart lesions, and 20–50% of patients with UPS had bony lesions including osseous glenoid lesions and Hill-Sachs (HS) lesions. There were no reports of nonoperative treatment for UPS. Almost all surgical treatments comprised standardized Bankart repair with or without augmentations including rotator interval closure and HS remplissage. Surgical treatment significantly improved the postoperative clinical scores. However, the rates of complete return to sports were 75% and 46% in the two studies, and 9% of patients (including contact or collision athletes) experienced re-injury around 1 year postoperatively. Therefore, an UPS in a collision and contact athlete should be treated not with standardized Bankart repair but with augmentation or coracoid transfer depending on the sports activity, patient wishes, and bony lesions.