In daily life, periarthritis of the shoulder often has the following symptoms and manifestations: The first is movement impairment. This is manifested as limited movement in various directions of the shoulder joint, including outward extension of the upper limbs, actions such as chest-expanding, taking off clothes, as well as significant difficulties in lifting and rotating. This can present as an inability to flexibly comb hair, wash face, and dress or undress. This is a key point in distinguishing frozen shoulder from other shoulder disorders. The second is pain. It manifests as pain in one shoulder joint without obvious trauma, which can be a dull pain or sharp, knife-like pain, often worsening at night and even causing awakening due to pain. The pain can radiate to the neck, back, forearm, and hand. The third is tenderness. Most patients with the condition widely experience tender points upon pressing around the affected joint. Muscle stiffness and atrophy may occur. The muscles around the shoulder, such as the deltoid and supraspinatus, can become stiff during the onset, and disuse atrophy may occur in the later stages.