Shoulder pain is an umbrella term for a range of diagnoses or disorders. Because the etiology of post-stroke shoulder pain is unknown, it is difficult for us to define shoulder pain. The most common clinical conditions are shoulder subluxation and shoulder-hand syndrome. It has been reported in the literature that the causes of shoulder pain after stroke can be divided into two categories: 1. Endogenous factors include: rotator cuff muscle group laceration, adhesive capsulitis, tendonitis, arthritis, joint trauma, brachial plexus nerve injury, post-stroke central pain, and complex regional pain syndrome. 2. Pathogenic factors include: upper extremity muscle weakness, shoulder subluxation, elevated or decreased muscle tone, abnormal movement patterns resulting in shoulder entrapment syndrome, sensory loss, lateral neglect syndrome, or visual field abnormalities, all of which may cause painful injury or chronic strain through poor posture.