Scaphoid fracture therapy
The therapy of a scaphoid fracture depends on the exact location of the fracture. Since, due to the anatomical conditions, the blood supply to the scaphoid is from far away from the body – i.e. from the fingers instead of the trunk – fractures of the scaphoid near the fingers heal much faster than fractures of the third of the scaphoid near the body. In any case, however, a healing period of 6 weeks can be assumed, usually in the range of 8-12 weeks.
The wrist and forearm are fixed with a plaster splint for this period. Since fractures of the extremities are considered to be particularly restrictive in everyday life, there are various possibilities for shortening the duration of therapy: The fragmented parts of the scaphoid could be fixed against each other by means of the so-called Herbert screw – a double threaded screw. This is a special implant that was developed specifically for the treatment of scaphoid fractures in the 1970s.
One end of the screw is screwed into the part of the fractured scaphoid close to the body, and one end into the part of the fractured scaphoid farther away from the body. Since the proximal thread has a smaller pitch than the distal thread, the distal scaphoid fragment is screwed to the proximal thread. The pressure that now acts on the two fragments (also called interfragmentary compression) accelerates the healing process.
The Herbert screw has no head, and is completely embedded in the bone. It is usually inserted through a small incision on the inside of the wrist. Its great advantage is that it significantly shortens the duration of therapy: the patient has to wear the cast for much less time, and thus has to struggle with limitations for less time.
In the case of a distal scaphoid fracture, immobilization is usually only necessary for two weeks, while a fracture close to the body requires only two to four weeks. If the therapy option is chosen without a Herbert screw, other complications such as muscle relaxation and joint stiffening must also be taken into account when immobilising the patient for up to 12 weeks. Since the joint can no longer be moved for such a long period of time, the supplying muscles consistently lose mass. Furthermore, calcifications and movement restrictions can occur. After a 12-week immobilization, physiotherapy or rehab should be considered, which follow the actual therapy of the scaphoid fracture as a consecutive form of therapy.
