Joint dislocation, with or without small bony or ligamentous avulsions, may be reduced closed, and the stability should then be evaluated. Open reduction is necessary if closed reduction is not successful.
If there is persistent instability, it is recommended to stabilize the joint with a temporary K-wire.
Dislocations of the 4th and 5th carpometacarpal (CMC) joint may be associated with a coronal fracture of the hamate, which also needs reduction to achieve joint stability. This can be achieved in a closed manner. If the coronal fragment can be reduced anatomically with joint congruity, there is often no need for fixation. If reduction is not successful (without congruity), open reduction and fixation should be considered. This should also be considered in noncompliant patients.
The patient is usually supine with the arm on a radiolucent side table.
Local or regional anesthesia may be applied.
A dorsal approach to the affected CMC joints may be used.
Protect the dorsal sensory nerve branches (radial and ulnar).
Dislocation is usually dorsally and may be reduced manually in a closed manner.
The coronal fragment of a hamate fracture is displaced with the dorsally dislocated 4th and/or 5th metacarpal base. Manual reduction of the dislocation may also reduce the fracture.
Open reduction is indicated if there are interposed soft tissue or bony fragments. Often, the joint capsules are ruptured, and the joint space is easily exposed.
Remove any soft tissue or bony fragments and reduce the joint.
Confirm reduction with an image intensifier and check the joint stability by passive flexion and extension of the fingers.
Often there is persistent instability, eg, subluxation or redislocation during the range of motion. In this case, add a temporary K-wire:
Repair the capsule if an open reduction was performed.
Bend the end of the K-wire above the skin and cut it with enough length to avoid migration.
This case shows K-wire stabilization of the 5th to the 4th metacarpal base and the hamate.
The aftercare can be divided into four phases of healing:
Full details on each phase can be found here.
To facilitate rehabilitation, it is important to control the postoperative pain adequately.
Rest the wrist with a well-padded below-elbow splint for about 2–4 weeks.
Splinting helps with soft-tissue healing.
X-ray checks of joint position have to be performed immediately after the splint has been applied.
Follow-up x-rays with the splint should be taken after 1 week and possibly every 2 weeks.
The K-wire can be removed 4–6 weeks after surgery.
Splint immobilization is continued until about 4 weeks after the injury. At that time, an x-ray without the splint is taken to confirm healing, and range of motion should be pain-free.