Arthroscopic Reconstruction of Chronic Unstable Scaphoid Nonunion

Background: Scaphoid nonunion treatment should be done by débridement, corticocancellous bone graft (vascularized or nonvascularized), and stable fixation by open exposure that increased the morbidity of the procedure. Wrist arthroscopy is a minimally invasive technique that preserves vascularization and neural proprioception.¹

Purpose: To assess our experience of arthroscopically assisted reconstruction in patients with unstable scaphoid nonunion.

Materials and Methods: A retrospective case series of chronic unstable scaphoid nonunions treated with dry arthroscopic reconstruction using two midcarpal portals. ¹ Dorsal intercalated segment instability (DISI) was corrected with a temporary Kirschner wire (K-wire) through the dorsal radius. Scaphoid defect was packed with cancellous bone graft from the distal radius across the radial-midcarpal portal.² Internal fixation was performed using a mini-Acutrak or HCS headless screw (Fig. 1). Fusion rates were recorded and radiographic and clinical evaluation was performed, with a mean follow-up of 16.8 (12–36) months. All patients were treated by the same surgeon.

Results: 13 patients (26 years mean age) were treated. Ten (76%) patients showed “humpback deformity” in preoperative radiological study. Union was achieved in all patients at 6 (4–8) weeks. Range of flexion-extension arc improved after surgery, from 138.4° to 165°. Scapholunate angle (SLA) and radiolunate angle (RLA) were significantly improved: SLA 67.7° to 47°; RLA 30.8° to 4°. Functional postoperative evaluation: mean Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire was 8 and visual analog scale (VAS) 0.7. No complications were observed. No reoperations were needed.

Conclusions: Arthroscopic reconstruction can be a useful alternative for chronic unstable scaphoid nonunion. In our experience it presents good clinical and radiological results, even in scaphoid waist nonunion with humpback deformity. It probably is limited for restoration of the normal carpal alignment, but it has positive effects on the recovery of clinical wrist function with comparable results to other open techniques.³

Fig. 1(a) Débridement was made through MC-r portal. (b) Cancellous bone graft was inserted. (c) Final arthroscopic view. (d) Insulin syringe used to insert bone graft. (e) DISI was corrected with a temporary K-wire through the dorsal radius. (f) Final fluoroscopic view with the screw across the scaphoid and the bone graft.

References

References

1 del Piñal F. Dry arthroscopy and its applications. Hand Clin 2011;27(3):335–345

2 Cohen MS, Jupiter JB, Fallahi K, Shukla SK. Scaphoid waist nonunion with humpback deformity treated without structural bone graft. J Hand Surg Am 2013;38(4):701–705

3 Kim JP, Seo JB, Yoo JY, Lee JY. Arthroscopic management of chronic unstable scaphoid nonunions: effects on restoration of carpal alignment and recovery of wrist function. Arthroscopy 2015;31(3):460–469 PubMed