The authors retrospectively reviewed 17 patients who underwent scaphoid resection and limited lunate-capitate arthrodesis for treatment of SLAC and SNAC arthrosis. At an average follow-up of 10 years, the functional and radiological results were similar in comparison to published reports of scaphoid resection with lunate-capitate-hamate-triquetrum arthrodesis for treatment of SLAC and SNAC arthrosis.
The authors emphasized 2 reasons for limiting a midcarpal fusion procedure to the capitolunate joint with preservation of the triquetrum and lunotriquetral articulation: 1) the normal innervation of the carpal ligaments that ascribe a proprioceptive role to the triquetrum (J Hand Surg Br 2007), and 2) the normal helicoidal motion of the triquetrum that may prevent ulnocarpal impingement in ulnar deviation. The authors asserted that impingement between the hamate and triquetrum following a limited lunate-capitate arthrodesis can be prevented by correcting the dorsal tilt of the lunate and avoiding excessive joint resection.
This procedure represents a variant of a midcarpal fusion for SLAC arthritis. It is unclear if the theoretical advantages of only fusing the capitate and lunate have any clinical relevance. This question will require further investigation. In addition, the original SLAC reconstruction only consisted of a capitolunate fusion. The ulnar carpal bones were added later only to help improve healing and the union rate.