The surgical sequelae of rotator cuff injury depend mainly on some preoperative conditions of the patient. If the quality of the rotator cuff is very poor and the patient has osteoporosis at the same time, the rivet may be pulled out of the bone very loosely, just like a nail hitting inside the sand, so the nail will be easily pulled out. In addition, if the rotator cuff is not of good quality, we all know that if a rag is sewn up, it can be easily torn off again, but if the rag itself is of good quality and sewn up again, the strength will be very good and the recovery will be very good. If a patient comes to the clinic late, they often come back a year or two years later with a rotator cuff injury, and the quality of the rotator cuff is often very bad, so there is a high risk of re-tearing after surgery. Therefore, the most worrying complication is the re-tear and the extraction of the rivets of the rotator cuff due to osteoporosis.