DORSAL APPROACH

USES

This approach is useful for wrist fusions, fracture fixation, and tenosynovectomy of the tendons.

ADVANTAGES

This midline approach can be extended as far proximally or distally as necessary.

DISADVANTAGES

There are no disadvantages to this approach.

STRUCTURES AT RISK

The tendons are at risk, but they are usually large and apparent, and easy to avoid. One structure at risk that is less apparent is the terminal branch of the posterior interosseous nerve, which gives articular branches to the dorsal wrist capsule. This nerve runs deep to the extensor tendons at the radial side of the fourth compartment. Inadvertent injury to this nerve has been reported to result in painful neuroma and may be a cause of dorsal wrist pain.

TECHNIQUE

An incision is made just to the ulnar side of Lister’s tubercle and can cross the wrist in a straight line. It is carried through the subcutaneous tissue. The tendons of the extensor digitorum communis are usually easily apparent and you typically retract them to the ulnar side. The dorsal wrist capsule can be opened longitudinally in a T-, H-, or U-shaped incision, which should provide exposure to the distal radius and all carpal bones. If necessary, this incision can be extended out onto the metacarpals for fusion procedures.

Deep to the extensor tendons (on the radial side of the base of the fourth compartment) is the posterior interosseous nerve. At this level, the nerve only gives off articular branches to the dorsal wrist capsule. The nerve can be left alone and usually does not get in the way of the dissection. In some cases, however, the nerve is isolated and divided (posterior interosseous neurectomy) to denervate the wrist for pain control. It can also be harvested for use as a nerve graft. Usually 1.5 to 2.0 cm of nerve graft can be harvested.

TRICKS

The major trick is to stay just to the ulnar side of Lister’s tubercle, so that you are in the interval between the third and fourth compartments. Typically, the carpal bone that is in view when you open the wrist capsule is the lunate. The scapholunate ligament is generally in line with Lister’s tubercle. The lunotriquetral ligament lies very ulnar to the capsular incision.

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