Who does it affect?
Approximately 80% of scaphoid fractures occur in males, with the highest incidence occurring between the ages of 20 and 30 years. Overall, it is felt that scaphoid fractures account for 11% of all hand fractures.
Some fractures of the scaphoid can be treated in a plaster cast. These are usually the fractures through the waist, which are undisplaced. However, scaphoid fractures that are displaced (i.e. the fracture fragments have moved apart) or fractures in the so-called proximal pole have a higher risk of not uniting, and are often treated operatively. Scaphoid fractures that are treated non-operatively usually involve a plaster of Paris immobilisation for a period of six to twelve weeks. Careful x-ray, follow up and CT scanning may be required to ensure the fracture has united.
Scaphoid fractures that occur in the proximal pole or scaphoid fractures that are displaced often require operative treatment. Surgery is performed under general anaesthetic or regional anaesthesia (only the arm is made numb). The surgery takes between thirty and forty minutes. A tourniquet is used, which is like a blood pressure cuff around the upper arm, which prevents blood from obscuring the surgeon’s view. There are two main types of scaphoid surgery for fractures.
The first is the traditional ‘open’ surgery. This usually involves a three to four centimetre incision either on the front or the back of the wrist, depending on the site of the fracture. The surgeon identifies the fracture under direct vision and places a bone screw, under x-ray control, into the scaphoid. The screw is buried deep inside the bone and is a permanent implant. After this type of surgery the patient is usually mobilised quickly, and plain radiographs or CT scans are performed to ensure the bone has united.
The second type of surgery is a more modern type of technique, which involves small (two or three millimetre incisions) this is called the ‘percutaneous fixation technique’. This had the added advantage of less surgical dissection and, hopefully, less trauma to the surrounding structures. However, the overall healing rate between the percutaneous and open techniques is probably similar. Post-operatively the rehabilitation is often quicker with the percutaneous technique due to less soft tissue trauma. This is a short video clip of Mike Hayton performing a percutaneous scaphoid fixation operation
Return to activities of daily living
Patients who are treated operatively, particularly with the percutaneous techniques, can return to driving and many activities of daily living within the first few days. Patients who are treated with more conventional, open four centimetre incisions usually return to driving within two to three weeks. Patients who are treated non-operatively, in a plaster of Paris, often find it difficult to drive whilst the cast is on. Indeed, many insurance companies prevent patients from driving in a cast.
Non-union is the major complication of scaphoid fractures. This is an inability of the fracture to heal. It is more common in the proximal pole fractures and those fractures that have significantly displaced. Overall, the non-union rate for scaphoid fractures is about 15%. An untreated scaphoid non-union is likely to go on to develop osteoarthritis over a ten to fifteen year period.
Treatment in plaster of Paris has very few complications, apart from non-union. Occasionally stiffness can occur in the digits if the fingers are not moved early.