Midcarpal Fusion with Excision of Scaphoid for Scapholunate Advanced Collapse ( SLAC )

Kang, Shin Young; Jeon, Chang Hoon; Han, Kyeong Jin; Min, Byoung Hyun

Abstract

Scapholunate advanced collapse (SLAC) deformity most often occurs with chronic rotary scaphoid instability from scaphoiunate ligament tear and scaphoid fracture. Prior to 1984 when Watson HK reported his concept on SLAC wrist deformity, the most popular procedure for this pathology was scaphoid implant arthroplasty with or without midcarpal fusion. We have reviewed 15 cases of SLAC deformity treated with scaphoid excision and midcarpal fusion from 1984 to 1993. Among them, scaphoid implants made of silicone were inserted in 4 cases. Scaphoid implant arthroplsty without carpal fusion has been excluded. The mean period of follow-up was 8.8 years and the mean age of patients was 47.5 years. Males and right wrists were predominant. Wrist motion was 56% and grip power was 71% of the normal opposite side. On the average overall, 8 patients had no pain and 7 patients had mild pain. The grade of pain was minimal, 0.5 in grade (Rating system: no pain-0, mild- 1, moderate-2, severe-3). However, all of the 4 cases of limited carpal fusion with a scaphoid implant developed silicone particulate induced synovitis and pain. The procedure appears to be effective in maintaining function of the hand with minimal pain up to 5.8 years. However, silicone scaphoid implant appears not to be necessary and is not recommended with a limited carpal fusion for this pathology.