Background and objective: Scaphoid Nonunion Advanced Collapse (SNAC) is a common pattern of degenerative wrist arthritis. Besides the conventional surgical method (4-corner fusion (4CF)), alternative methods have been described as capitolunate arthrodesis. The objective of this study was to investigate the surgical result of the capitolunate fusion and the results from the post-surgical one-year follow-up.
Materials and methods: From March 2008 to March 2017, among 21 patients with SNAC wrist, stages 2 and 3, 14 were included. Following the scaphoid resection, by preserving capitate convexity and concavity of the lunate's distal face, the lunate was reduced on the capitate, and capitolunate fusion was done using Herbert screws, in the antegrade direction. All patients were followed for one year. Clinical examinations and wrist x-rays were investigated in each follow-up session. Visual analog score (VAS), Disability of the Arm, Shoulder, and Hand (DASH score) were compared before and after the surgery. Grip strength, flexion and extension were recorded one year after surgery, compared with intact non-operated hand.
Results and conclusion: Union occurred in all of the patients. VAS score and DASH score decreased (from 6.5 to 3.3 and from 46.14 to 30.43). The VAS score and DASH score decreased significantly after a one-year follow-up (P-value ≤ 0.05). Operated hand flexion was 34.30° (20-80), the extension was 32.58° (20-60), and grip strength was 29.69 Kg (22-40). Non-operated hand flexion was 56.38(30-80), the extension was 61.8 (38-80), and grip strength was 44.54 Kg (28-76). These differences were statistically significant (P-value ≤ 0.05). Based on our study results, scaphoid excision and capitolunate arthrodesis resulted in an acceptable functional wrist with minimal pain. This finding reflects that capitolunate arthrodesis is a time-saving and easy-to-learn procedure. Minimal morbidity of this method supports the idea that the capitolunate arthrodesis is an acceptable alternative to 4CF, the conventional surgical method.