gms | German Medical Science

Objectives/Interrogation: Midcarpal arthrodesis with excision of scaphoid is a common procedure for the surgical treatment of scaphoid nonunion advanced collapse and scapholunate advanced collapse wrists. However, this method has been associated with the increased risk of complications including nonunion and implant failure. The purpose of this study was to evaluate the results of surgical treatment of patients with SNAC and SLAC wrist in stage II and III.

Methods: Between 2005 and 2017 we performed 11 midcarpal arthrodeses in eleven patients (all men averagely aged 42) with 8 SNAC- and 3 SLAC-wrist. The average interval between the injury and surgery was 5 years. The fusion between lunate and capitate, as well between triquetrum and hamate, was performed together with the excision of the scaphoid bone and radial styloidectomy (5 cases). The Kirschner wire (6) and headless compression screws (5) were used for bone fixation. In eight cases we performed the bone graft transfer from iliac crest or used the excised scaphoid. We examined all patients according to the radiological bone healing, active range of wrist motion (AROM), grip strength, pain score (VAS 1-10), complications, DASH-questionnaire, Cooney-Krimmer score. The mean follow-up was 2,5 years (12 months - 13 years). Statistical Analysis was done using SPSS 21; paired t-test; paired Wilcoxon-test.

Results: Radiographic signs of bone fusion were observed in 3-4 months after the operation in all patients. The preoperative AROM was 71,1±14,3% of the contralateral hand, the postoperative one was 58,8±10,4% (p=0.013). Grip strength improved from 58,6±17,6% to 76,6±10,8% (p=0.008). The average intensity of wrist pain at rest and on exertion was 2,6±2,3 and 6,8±1,5 points (p=0.005) preoperatively, and after the surgery it was 0,6±0,9 and 3,1±1,9 points (p=0.003) respectively. The rates of DASH score prior to the operation were averagely 44,5±13,6 points; after the surgery they made 20,6±8,2 points (p=0.003). The function scores measured by the Cooney-Krimmer wrist score improved significantly from 42,7±12,5 to 71,0±9,4 points (p=0.005). The errors and complications included the damage of lunate and radius cartilage (2), DISI deformity (1), K-wire break (1) and drill break (1). There were no changes in the professional activity of the patients.

Conclusion: The midcarpal arthrodesis is a reliable procedure for SNAC and SLAC to achieve a stable and pain-free wrist with the increase of wrist strength due to the decrease of the overall range of motion.