Is Arthroscopic Bone Graft and Fixation for Scaphoid Nonunions Effective?

Abstract

Background: Arthroscopic management of scaphoid nonunions has been advanced as a less invasive technique that allows evaluation of associated intrinsic and extrinsic ligamentous injuries; however, few studies have documented the effectiveness of arthroscopic treatment of scaphoid nonunions and which intraarticular pathologies coexist with scaphoid nonunions.

Questions/purposes: (1) What are the outcomes of arthroscopic management of scaphoid nonunions as assessed by the proportion of patients achieving osseous union, visual analog scale (VAS) pain score, grip strength, range of motion, Mayo Wrist Score (MWS), and Disabilities of the Arm, Shoulder and Hand (DASH) score? (2) What complications are associated with arthroscopic scaphoid nonunion management? (3) What forms of intraarticular pathology are associated with scaphoid nonunions?

Methods: Between 2008 and 2012, we treated 80 patients surgically for scaphoid nonunions. Of those, 45 (56%) had arthroscopic management. During that time, our general indications for using an arthroscopic approach over an open approach were symptomatic scaphoid nonunions without necrosis of the proximal fragment, severe deformities, or arthritis. Of the patients treated arthroscopically, 33 (73%) were available for followup at least 2 years later. There were five distal third, 19 middle third, and nine proximal third fractures. The mean followup was 33 months (range, 24-60 months). Union was determined by CT taken at 8 to 10 weeks after operation with bridging trabecula at nonunion site. VAS pain scores, grip strength, active flexion-extension angle, MWS, and DASH scores were obtained preoperatively and at each followup visit. The coexisting intraarticular pathologies and complications were also recorded.

Results: Thirty-two (97%) scaphoid nonunions healed successfully. At the last followup, the mean VAS pain score decreased (preoperative: mean 4.5 [SD 1.8], postoperative: mean 0.6 [SD 0.8], mean difference: 3.9 [95% confidence interval {CI}, 3.2-4.6], p < 0.001) and the mean active flexion-extension angle increased (preoperative: mean 100° [SD 26], postoperative: mean 109° [SD 16], mean difference: 9° [95% CI, 2-16], p = 0.017). The mean grip strength increased (preoperative: mean 35 kg of force [SD 8], postoperative: mean 50 kg of force [SD 10], mean difference: 15 kg of force [95% CI, 11-19], p < 0.001). The mean MWS increased (preoperative: mean 56 [SD 23], postoperative: mean 89 [SD 8], mean difference: 33 [95% CI, 26-41], p < 0.001) and the mean DASH score decreased (preoperative: mean 25 [SD 18], postoperative: mean 4 [SD 3], mean difference: 21 [95% CI, 15-28], p < 0.001). There were no operation-related complications and no progression of arthritis at the last followup. Seventeen patients had coexisting intraarticular pathology, including nine triangular fibrocartilage complex tears (seven traumatic and two degenerative), 17 intrinsic ligament tears (nine scapholunate interosseous ligament tears and eight lunotriquetral interosseous ligament tears), and five mild radioscaphoid degenerative changes.

Conclusions: Arthroscopic management of scaphoid nonunions without severe deformities or arthritis was effective in this small series. Although intraarticular pathologies such as triangular fibrocartilage complex tears and intrinsic ligament injuries commonly coexisted with scaphoid nonunions, patients generally achieved good results.

Level of evidence: Level IV, therapeutic study.

Figures

Fig. 1A–F

(A–B) Preoperative radiographs of a 45-year-old patient show a minimally displaced scaphoid nonunion. (C–D) Coronal and sagittal CT scans of this patient indicate the scaphoid nonunion with cystic degeneration at the nonunion site without humpback deformity. (E–F) These findings are confirmed with comparison to contralateral normal radiographs.

Fig. 2

A CONSORT flow diagram shows enrollment and analysis of this study.

Fig. 3A–D

(A) The scaphoid nonunion site is completely débrided using a fine curette and motorized shaver. (B) Then, the nonunion site was reduced by the manipulation of the distal fragment with a probe and fixed with a Kirschner wire under arthroscopic and fluoroscopic guidance. (C) A guidewire was inserted through the axis of the scaphoid for a headless compression screw through the proximal 3–4 portal. (D) A percutaneous cancellous iliac bone graft was performed through the scaphotrapezial trapezoidal portal via a 3.5-mm burr sheath and the grafted bone (GB) is packed into the nonunion site using a periosteal elevator. C = capitate; S = scaphoid; L = lunate; R = radius; Sd = distal fragment of the scaphoid; Sp = proximal fragment of the scaphoid.

Fig. 4A–C

(A) Sagittal CT scan taken 8 weeks after surgery shows bony union. (B–C) Radiographs obtained at 2 years postoperatively demonstrate solid union and no arthritic changes.