Single-Cut Single-Screw Capitate-Shortening Osteotomy for Kienbock's Disease

Abstract

Background Kienbock's disease, in spite of an uncertain natural history, is known to cause lunate compromise, leading to central column collapse, carpal instability, and degenerative arthritis of the wrist. Joint leveling procedures are performed in the early stages of Kienbock's disease to "unload" the lunate. Capitate shortening is the preferred procedure in Kienbock's patients with positive ulnar variance. Description of Technique We describe the rationale and a simplified technique of capitate shortening in early Kienbock's disease. This is a single-cut osteotomy with single-screw stabilization. Patients and Methods We have performed this technique in three cases. We present a case of a 26-year-old male who presented with a 1-year history of pain in his right wrist. Radiology performed demonstrated lunate sclerosis. Diagnostic arthroscopy revealed healthy articular surfaces. Single osteotomy capitate shortening was performed with an oscillating saw and fixed with a single cannulated compression screw. A shortening of 1.5mm was obtained with this technique. Results At 1- to 2-year follow-up, all three patients had considerable pain relief but did not have a complete resolution of pain. There was a significant improvement in function and grip strength. There have been no cases with infection, nonunion, avascular necrosis or a need for a salvage procedure. Conclusion The simplified technique of capitate shortening is easy to perform, less traumatic to the capitate vascularity, and leads to good short-term functional results.

Keywords: Kienbock's disease; capitate osteotomy; capitate shortening; capitate vascularity; joint leveling.

Fig. 1

Capitate vascularity. ( A ) The venous anatomy of the capitate. Note the single large vein draining the proximal capitate (white arrow). ( B ) The intraosseous arterial supply. (Reproduced with permission of Crock .)

Fig. 2

Different methods of fixation for capitate-shortening osteotomy.

Fig. 3

Preoperative radiographs showing Kienbock's disease with lunate sclerosis.

Fig. 4

Computed tomography images showing lunate sclerosis and a coronal fracture without carpal collapse.

Fig. 5

The osteotomy is designed relative to the axis of the lunocapitate joint, at the level of the STT joint. STT, scaphotrapeziotrapezoid.

Fig. 6

A small area of the third MC base is removed with an osteotome to ensure the correct line of entry of the wire. A threaded guidewire is then passed down the capitate. On the lateral projection, the wire is placed parallel to the dorsal cortex of the capitate. A cannulated drill is advanced over the wire and into the head of the capitate. MC, metacarpal.

Fig. 7

With a 6-mm-wide fine-tooth oscillating saw, a transverse capitate osteotomy is made distal to the midwaist (middle one-third), at the level of the scaphotrapeziotrapezoid joint.

Fig. 8

The K-wire is again inserted and then a single cannulated compression screw (2.2 mm) is advanced over the wire to compress the osteotomy.

Fig. 9

Follow-up radiographs: united capitate osteotomy with no signs of avascular necrosis. No further collapse in the lunate was noted.