Because the cut ends of a tendon usually separate after an injury, it is not likely that a cut tendon will heal without surgery. Your doctor can advise you on how soon surgery is needed after a flexor tendon is cut. There are many ways to repair a cut tendon, and certain types of cuts need a specific type of repair. If unprotected finger motion begins too soon, the tendon repair is likely to pull apart. After four to six weeks, the fingers are allowed to move slowly and without resistance.
Healing takes place during the first three months after the repair.
In most cases, full and normal movement of the injured area does not return after surgery. If it is hard to bend the finger using its own muscle power, it could mean that the repaired tendon has pulled apart or is bogged down in scar tissue. Scarring of the tendon repair is a normal part of the healing process. But in some cases, the scarring can make bending and straightening of the finger very difficult. Depending on the injury, your doctor may prescribe therapy to loosen up the scar tissue and prevent it from interfering with the finger's movement.