The bone on both sides of the hand finger protrudes after tendon rupture surgery, which may be tendon scar, cyst, bone spur, etc. 1. Tendon scar: It may be a tendon scar on the anastomosis of the middle finger caused by inappropriate intraoperative suture, local infection or inflammation. 2. Cyst: It may be a cystic benign mass in the area of the middle finger. The contents of the sac are usually fluid of a different nature and can occur in various parts of the body. Therefore, a cyst may be a protruding bone on both sides of the middle finger after tendon rupture surgery. 3. Bone spurs: Bones protruding from both sides after tendon rupture of the middle finger may also be bone spurs, which usually form in the joints where the two ends of the bones are in contact with each other, and may grow along the edges of the bones of the limbs, with the morphology of a bony protrusion. There may be other reasons for the protruding bones on both sides of the hand after tendon rupture surgery, it is recommended to go to the regular hospital in time to improve the relevant examination, after clarifying the cause of the disease, and then carry out targeted treatment or treatment under the guidance of the doctor.