The following are common causes of soreness in the shoulder and back: First, usually overworking and using the shoulder and back for a long time to bear weight can lead to muscle strain, which can cause soreness in the shoulder and back. In addition, some patients work in a fixed position for a long time and have poor posture, which can lead to soreness in the shoulder and back muscles. Secondly, cervical spondylosis, cervical disc herniation, cervical spinal stenosis can all cause nerve compression, and the innervation area, such as the back of the shoulder, can have soreness and pain symptoms. In the early stage, the pain symptoms are not obvious, and the gradual aggravation will make the pain symptoms significantly worse. Thirdly, periarthritis of the shoulder joint, which can also stimulate soreness and pain symptoms in the back of the shoulder, mainly occurs in the early stage of frozen shoulder, while severe and persistent pain symptoms in the back of the shoulder can occur in the middle and late stages.