Treatment is directed at the arthritic joint between the scaphoid and radius. The joint between the radius and lunate is consistently not affected with this type of post-traumatic arthritis, which enables a procedure that preserves functional wrist motion, and restores pain-free grip strength.
The 2 main treatment options are PRC (proximal row carpectomy) and midcarpal fusion with scaphoid bone excision. For patients with SLAC arthritis related to a scaphoid nonunion(also called SNAC arthritis), a 3rd option exists--excision of the distal pole of the scaphoid.Your treatment option will be affected by the degree of disease on xray, your preoperative motion, whether you are a laborer, and what other health problems you have. Whether you smoke or not may influence decision-making too, since healing (union) rates may decline following fusions in smokers.
For SLAC arthritis a midcarpal fusion (capitolunate) with excision of the scaphoid provides superb pain-relief and 60-70% of normal motion. Radioulnar kinematics (motion)has been found to be improved when the triquetrum is excised along with the scaphoid; in such cases a fusion is obtained between the capitate and lunate only. Union rates with both two-bone and four-bone fusion are 90% but a cast is required for the 1st 6 weeks or so. Motion and grip strength will continue to improve for 12-18 months.
Midcarpal fusion with scaphoid excision and PRC result in comparable outcomes. The decision to perform one over the other will revolve around the extent of your arthritis on xray, whether you are a laborer,what other recreational demands you place on your wrist, and whether you have a smoking history.
