Scapholunate advanced collapse and scaphoid nonunion advanced collapse arthritis--update on evaluation and treatment.

Scapholunate advanced collapse (SLAC) and scaphoid nonunion advanced collapse are common patterns of wrist arthritis. Scaphoid nonunion advanced collapse is caused by trauma, whereas SLAC wrist may also result from chronic pseudogout and can appear bilaterally without a clear history of injury. Surgical treatment for SLAC wrist includes 4-corner arthrodesis, capitolunate arthrodesis, complete wrist arthrodesis, proximal row carpectomy (PRC), denervation, and radial styloidectomy. Scaphoid nonunion advanced collapse wrist has the additional surgical option of excision of the distal ununited scaphoid fragment. Controversy persists over the relative merits of PRC versus 4-corner arthrodesis and whether PRC may be performed in the setting of capitate arthritis.