Dorsal Capsulodesis

Surgical technique

• Longitudinal incision, dorsoradially about the wrist.
• Dissection is taken down between the third and fourth extensor compartments, exposing the dorsal wrist capsule.
• A proximally based, 1 cm wide flap of dorsal capsule, which includes part of the dorsal radiocarpal ligament, is developed.
• The scapholunate interval is reduced using two Kirschner wires as joysticks. The lunate is flexed, and placing pressure on the scaphoid tubercle while ulnarly deviating the wrist extends the scaphoid. The scapholunate interval is pinned with two to three 1.2mm Kirschner wires.
• A Kirschner wire is passed across the scaphoid capitate interval as well. The area of the dorsal distal scaphoid that is devoid of articular surface is identified. A notch is made in this surface that is proximal to the articular surface of the distal scaphoid but distal to the midaxis of rotation. A drill hole is made from dorsal to volar, exiting the scaphoid tubercle. The capsular flap is sutured to the dorsal scaphoid using a pull-out suture placed through the drill hole and tied over a button on the scaphoid tuberosity volarly.
• An alternative method of fixation includes a suture anchor placed in the dorsal distal pole of the scaphoid. This type of fixation will preclude the need for the pull-out wire or suture tied over a button.
• The wrist is splinted for approximately 2 to 3 months, at which time the Kirschner wires are removed and a range of motion program started.

Modification of dorsal capsulodesis

Slater et al. proposed an alternative method in performing the procedure termed the dorsal intercarpal ligament capsulodesis (DILC). In this procedure, the dorsal intercarpal ligament, based ulnarly on the triquetrum, is elevated off the trapezoid and sutured to the distal aspect of the scaphoid. The authors compared DILC to the dorsal capsulodesis described by Blatt using a cadaveric model. The scapholunate angle reduced equally with both procedures, although the DILC was found to decrease the scapholunate gap better than the Blatt capsulodesis. They proposed that DILC has certain theoretical advantages. The DILC links the scaphoid and triquetrum directly, keeping the proximal carpal row linked together as a functional unit, which may account for the decreased diastasis. It was hypothesized that the reduction of the scapholunate angle is related in part to the position of the dorsal intercarpal ligament. It uses the capitate as a pulley for the ligament to prevent flexion of the distal pole of the scaphoid. In addition, since the dorsal intercarpal ligament does not tether the scaphoid to the distal radius, improved wrist flexion may be expected clinically.
 

Another indirect soft tissue tether described for scapholunate instability involves the use of a distally based split extensor carpi radialis longus (ECRL) tendon that is sutured to the dorsal scaphoid. Dagum et al. compared the dorsal capsulodesis described by Blatt to the split ECRL tendon reconstruction using a cadaveric model of static scapholunate dissociation. They showed that both procedures reduced the scapholunate gap and scapholunate angle. The carpal row index (C/R index) also was increased with both reconstructions.

Last updated 16/09/2004