A 30-year-old right-hand dominant man presented 2 weeks after punching a machine with the radial aspect of his arm and hand.
On examination, he was noted to have significant bruising, tenderness over the lunotriquetral (LT) interval, and a positive shear, shuck, and compression test. MRI demonstrated disruption of the dorsal capitohamate (CH) and the dorsal LT ligaments (▶Fig. 76.1a). Radiographs did not reveal a fixed volar intercalated segment instability (VISI) deformity (▶Fig. 76.1b). The patient was initially treated with 4 weeks of cast immobilization, which was not successful. Subsequently, he underwent a midcarpal diagnostic injection with local anesthetic and steroid, which provided good pain relief.
The patient presented with acute traumatic axial midcarpal instability without evidence of fixed VISI deformity or carpal collapse. Initial treatment should include a period of conservative management with immobilization. If failed, operative procedures to reestablish the lunocapitate axis and stabilize the proximal carpal row should be attempted, if there is no evidence of carpal collapse or fixed deformity. Wrist arthroscopy should be performed to inspect the LT stability, as well as the stability of all other intercarpal joints. The LT joint can be stabilized with a reconstruction or a direct repair. The senior author’s preferred technique is a reconstruction using a strip of the extensor carpi ulnar (ECU) tendon when both the volar and the dorsal ligaments are disrupted.
• Wrist arthroscopy should be performed to thoroughly assess the stability of all intercarpal joints and articular surfaces.
• The LT joint can be stabilized with a reconstruction (if both volar and dorsal ligaments are incompetent) or a direct dorsal repair (if volar ligament is competent, and the tissue quality of the dorsal ligament is adequate).
• Reconstruction with a strip of the ECU tendon provides uniformly good outcomes.
The patient was taken to the operating room for a diagnostic wrist arthroscopy, CH fusion with iliac crest bone autograft, and an LT reconstruction. The patient was placed in the supine position with an arm board. General endotracheal anesthesia was administered and the operative extremity was prepped and draped in the usual sterile fashion. A tourniquet was applied and a standard wrist arthroscopy was performed using the 3–4, 4–5, radial midcarpal, ulnar midcarpal, and 6U portals. The scapholunate (SL), LT, and midcarpal joints are inspected. Geissler stage II instability was noted in the SL interval, stage III in the LT interval, and stage IV in the CH interval.
A mid-axial longitudinal dorsal wrist incision was made and an ulnarly based extensor retinacular flap was created. A posterior interosseous nerve neurectomy is performed. A radially based dorsal capsular flap is then created, with care to avoid damage to the underlying carpal cartilage. The intercarpal joints are then inspected under direct visualization to confirm disruption of the dorsal ligaments. Attention was first directed to the CH interval and the articular surfaces of the capitate and the hamate were prepared with a small burr. Iliac crest autograft was inset and the interval was fixed with two staples.
Attention is then directed toward the LT interval. The joint should be inspected for any remnants of the dorsal ligaments. The ECU tendon is identified in the forearm and a no. 15 blade scalpel is used to make a transverse incision over the proximal aspect of the tendon. One-third of the ECU tendon is isolated and brought into the wound distally (▶Fig. 76.2a). Bone tunnels are drilled in the lunate and the triquetrum. The lunate tunnel is drilled in a radial dorsal to volar ulnar direction, while the triquetral tunnel is drilled in an ulnar dorsal to radial volar direction. A 28-G wire is then sutured into the free end of the ECU tendon. It is then passed through the drill holes in the triquetrum and then the lunate (▶Fig. 76.2b). The tendon is then folded back on itself, passed underneath its distal insertion, and pulled tight to reduce the LT interval (▶Fig. 76.2c).