The Hip book
Home » Joints » Wrist » Hamate

Hamate


- See: Blood Supply to the Wrist

- Discussion:
    - anatomy of hook of hamate:
          - is situated slightly distal and radial to the pisform;
          - forms lateral (radial) border of tunnel of guyon, which transports ulnar nerve and artery to hand;
          - vascular supply: vessels enter hook at two sites - hook radial base & hook ulnar tip;

- Hook of Hamate Fracture:
    - frxs of the hook may result from athletic activity (swinging golf club, etc) but may occur from direct blow;
           - hook of the hamate is particularly at risk in batters and golfers;
    - avascular changes may follow fracture of hook in hamate, and these may lead to hook necrosis and non union;
    - pattern of vascular supply suggests that most acute hooks frx should have adequat blood supply to heal if well immobilized immediately;
    - exam:
    - pain is accentuated w/ axial loading of ring and little finger metacarpals;
           - dx is usually confirmed by point tenderness over hook 1 cm distal and radial to the pisiform;
           - almost all patients complain of pain and tenderness on ulnar side of palm or on the dorsoulnar aspect of the wrist;
           - most common symptom is pain in the palm aggravated by grasp;
           - diminished grip strength, dorsal wrist pain, ulnar nerve paresthesias or weakness, and mild carpal tunnel syndrome are frequent.
    - diff dx:
           - intra-articular injuries, though rare, may also occur in hamate;
           - occasionally longitudinal sprain between trapezoid & capitate or capitate & hamate gives rise to ill-defined pain in ulnar aspect of the wrist;
    - radiographs:
           - see 15 deg reversed oblique view:
           - fractures of the body occur more frequently than frx of hook;
           - frx of hamate are difficult to dx as routine AP & lateral films fail to show frx;
           - most of frx can be diagnosed conclusively on carpal tunnel view or on special oblique radiograph w/ wrist supinated
           - CT scan will also demonstrate this fracture;
    - teatment:
           - pattern of vascular supply suggests that most acute hooks frx should have adequat blood supply to heal if  well immobilized immediately;
           - immediate immobilization of acute frxs may promote fracture healing and obviate operative intervention;
           - origin of the flexor digiti minimi brevis and opponens digiti minimi may cause a failure of a hamate fracture to heal;
           - nonathletic injury or crush injury adversely affects outcome;
           - pts w/ excisions of hook of hamate usually return to their pre-injury level of activity;
           - ORIF is possible but offers little advantage over excision, which typically produces excellent results



The Lateral Approach Compared With the Volar Approach for Exposure of the Hook of the Hamate.

Fracture of the hook of the hamate

The lateral approach compared with the volar approach for exposure of the hook of the hamate.

Ununited fracture of the hook of the hamate.

Fracture of the hook of the hamate in athletes.

Hamatometacarpal fracture-dislocation: classification and treatment.

Fracture of the hook of the hamate: acute treatment.

Hook of hamate vascularity: vulnerability to osteonecrosis and nonunion.

Hook of Hamate Pull Test