It is not common to treat a mallet finger surgically if bone fragments or fractures are not present. Surgical treatment of the damaged tendon usually requires a tendon graft â tendon tissue that is taken (harvested) from another part of your body â or even fusing the joint straight.he injury may rupture the tendon or pull the tendon away from the place where it attaches to the finger bone (distal phalanx). In some cases, a small piece of bone is pulled away along with the tendon. This is called an avulsion injury. (Top) A rupture of the extensor tendon.