After the tendon is sutured, it takes about four weeks to heal. However, it takes at least 6 weeks to 3 months to reach the previous strength. Therefore, after a tendon injury, it takes about three months to fully recover from the suture. There are two main stages of recovery from a tendon injury: the first stage is up to four weeks after surgery. During this time, the surgeon will use a variety of fixation methods to completely immobilize the bone and joint around the injured tendon. For example, the use of kyphosis pins, or casts and braces. At this point, the recovery of the injured tendon can only be facilitated by keeping the injured tendon severed in a stable and inactive environment, and subsequently keeping it under a minimum tension. The second stage is after 4 weeks. At this time, the surgeon will remove the immobilization device and gradually start functional exercises. At this time, the functional exercise consists of both active and passive exercises. Active exercises are performed by the patient himself to restore the muscle strength around the injured tendon. Passive exercise, on the other hand, is to passively move the joints around the injured tendon with the help of family members or doctors in order to relieve the scarring and adhesions caused by prolonged immobilization and tendon injury.