Arthroscopy-assisted bone grafting for the treatment of SNAC stage I without radial styloidectomy

Abstract

To report the clinical and radiological outcomes of arthroscopic bone grafting and percutaneous K-wire fixation without radial styloidectomy in patients with scaphoid nonunion advanced collapse (SNAC). We retrospectively analyzed the records of 15 patients with SNAC who were treated with arthroscopic bone grafting and percutaneous K-wire fixation and subsequently followed up for a minimum of 1 year between November 2009 and March 2018. The clinical outcomes were evaluated by comparing the range of motion (ROM), grip strength, the modified Mayo Wrist Score, and visual analog scale (VAS) scores for pain, all of which were measured preoperatively and at the last follow-up. The radiologic outcomes were evaluated by comparing the scapholunate (SL) and radiolunate (RL) angles preoperatively and at the last follow-up. All 15 cases of nonunion were resolved. The average radiologic union time was 9.7 ± 1.2 weeks. The average VAS score increased from 5.7 ± 2.3 (range, 2 − 10) preoperatively to 1.3 ± 1.3 (range, 0 − 3) at the last follow-up ( P < .05). The average modified Mayo wrist score increased from 58.3 ± 14.0 preoperatively to 80.0 ± 9.2 at the last follow-up ( P < .05). The mean ROM of the wrist improved, but there was no statistical significance. At the last follow-up, the mean flexion and radial deviation on the affected side were significantly decreased, and the mean extension on the affected side was significantly improved compared to the normal side ( P < .05). The mean preoperative SL and RL angles were 66 ± 11.9° and 7.2 ± 6.8°, respectively, and were decreased to 50.4 ± 7.5° and 6.4 ± 5.2°, respectively, at the last follow-up. The mean SL angle was significantly corrected ( P = .01). Arthroscopic bone grafting and percutaneous Kerschner (K)-wire fixation without radial styloidectomy are considered to be very effective methods for correcting scaphoid deformities to treat SNAC stage I. However, caution may be needed during the surgery to prevent reductions in flexion and the radial deviation of the wrist.

Arthroscopic surgery for scaphoid nonunion: a 10-year systematic literature review

“…Some studies included patients with stage I SNAC [ 15 , 18 , 19 , 21 ] and radio-carpal or midcarpal osteoarthritis [ 21 ], with imaging suggestive of avascular necrosis [ 21 ]. One author [ 19 ] considered nonunion to be a permanent fracture at 3 months instead of 6 and described revision surgery, SNAC grade II, and avascular necrosis of the proximal pole.…”

“…Seven authors performed postoperative CT scans as routine to confirm union, and three used CT to better study doubtful cases [ 15 , 17 , 25 ]. One author did not use CT in any patient to confirm union [ 21 ].…”

Arthroscopic synovectomy of the wrist

“…Lee and Jung [20] have reported that in 15 SNAC stage I patients, pain in the radial side is improved by only performing sufficient arthroscopic debridement including joint capsule for synovitis and degenerative change around the radial styloid process without performing radial styloidectomy after correcting scaphoid nonunion. Therefore, for non-weight-bearing joints such as wrist in degenerative osteoarthritis patients, arthroscopic synovectomy including debridement is expected to lead to symptom improvement and joint movement increase.…”

“…Synovectomy is often an integral part of procedures for treating conditions of degenerative nature amenable for arthroscopic surgery, such as wafer resection for ulnar impaction syndrome (UIS), debridement in scaphoid-trapezium-trapezoid (STT) osteoarthritis, radial styloidectomy for styloid impaction on the scaphoid, scaphoid nonunion advanced collapse (SNAC), and triangular fibrocartilage complex (TFCC) resection for degenerative changes [18][19][20][21][22]. So far, in patients with osteoarthritis, the effect of arthroscopic synovectomy is probably short-term.…”

Magnetic resonance imaging analysis of the distribution of cartilage damage in scaphoid nonunion

“…In this system, the interface between the fractured proximal pole of the scaphoid and the radius is not included since it is frequently spared. The Vender classification of SNAC wrist has become the standard system for communication between professionals and researchers (Abdelaziz et al., 2020; Lee and Jung, 2022; Nakamoto et al., 2023).…”