RESUMEN
Patients with rotator cuff tears often have repeated irregular neck and shoulder pain, and all of them are aggravated at night. The patient is very painful and cannot suffer from lateral position. Most of them cannot or do not do the exercises such as stretching the elbow and bending the arm, which seriously affect sleep. Numerous studies have shown that in addition to inflammation, the two-way interaction to the circadian clock, the circadian clock also regulated many aspects of the immune system. And the mechanism of night pain caused by rotator cuff injury was related to factors such as inflammation of the acromion sac. This suggests that the night pain of rotator cuff tears may have a circadian rhythm. This article mainly reviews the mechanism of night pain caused by rotator cuff tears.