Wrist Fractures
Scaphoid fracture
The most common carpal fracture. Volumes have been written about the appropriate management of this fracture.
Suspected after a fall onto the hand and tenderness over the scaphoid or in the anatomic ‘snuff box’, (scaphoid impaction test, SIT, is positive, Swelling and ‘thickening’ in the AP length of the wrist may be seen. Resisted pinch is painful. The x-rays should include a ‘scaphoid view’ (PA in ulnar deviation).
X-rays may be negative. Place the patients in a ‘scaphoid cast’ and rex-ray at two weeks; if still pain with negative x-rays, consider a truly ‘occult’ fracture, or a scaphoid-lunate ligament injury and obtain stress x-rays and a bone scan.
The median time for union of a scaphoid fracture is twelve weeks (The more proximal the fracture is, the more likely avascular necrosis and / or non-union).
Treatment: Immobilize tubercle or non displaced (no displacement) waist fractures in a short arm cast (including the thumb up to, but not including the IP joint) with the thumb pulp opposed to the pulp of the middle finger for six weeks. If no evidence of union progressing fix the fracture with a Herbert screw. Displaced waist and proximal third fractures are fixed straight away with a Herbert screw. If early mobilization is desired, as with athletes, the fracture is also fixed immediately. Return to sport three weeks after surgery in non contact sports (contact and collision are not permitted until union has occurred and not before six to eight weeks post fracture).
Other carpal fractures
Fractures of the triquetrum are the second or third most common carpal fracture (usually avulsions from the dorsum of the bone). Immobilize in a splint for three to four weeks to allow pain to settle for resumption of activity (occasionally becomes source of ongoing pain and fragment excision and ligament repair may be required).
Fracture of the hook of hamate
These account for 2% of carpal fractures and are common in ‘club’ ‘racquet’ sports (hockey, golf, baseball, cricket and tennis). The mechanism of injury is an impact between the base of the club, bat or racquet and hypothenar eminence (The handle of a cricket bat is sprung to absorb impact and so a ‘batsman’ is less likely than a ‘batter’ to incur fracture). The golfer implodes the ground on the swing.