[Partial arthrodesis of the carpal bones in advanced carpal collapse in chronic scapho-lunar instability and following scaphoid pseudoarthrosis].

Degenerative arthritis of the wrist as a consequence of chronic scapho-lunate instability or chronic scaphoid non-union follows very specific patterns. Joint destruction occurs primarily in the radio-scaphoid and in the luno-capitate joints while the radio-lunar joint is preserved. Treatment by partial carpal fusion between capitate, scaphoid and lunate aims at reconstruction of correct length of the central column and restoration of normal carpal height by reducing the dorsiflexed lunate bone, thereby decompressing the painful radio-scaphoid joint. We have carried out the procedure in 21 cases. At follow up (19 months) 17 patients were free of pain and 4 patients experienced major improvement but had some residual pain. The mean range of motion of the wrist was 57 degrees, representing a loss of 34% of preoperative range of movement. Bony union was achieved in all cases. All patients returned to their former occupation. Partial carpal fusion for treatment of SLAC-wrist and scaphoid nonunion has proven successful with respect to pain relief and partial preservation of wrist motion avoiding complete fusion or arthroplasty of the wrist.