Arthroscopic Treatment of Scaphoid Nonunion Without Bone Graft and Distal Radius Core Decompression

Abstract

Introduction: The scaphoid bone is the most commonly broken carpal bone and an untoward characteristic of this bone is its unpredictable union. The management of scaphoid nonunion still remains controversial with a reported failure rate up to 40% and absence of a “gold standard” of treatment. Based on the new concepts of the potential osteogenic capacity of the nonunion cells with the ability to heal, the encouraging results generated by increasing vascularization within the metaphyseal radius, and ulna decompression used in the treatment of Kienböck disease as well as the advantages of minimal surgical trauma using percutaneous and arthroscopic techniques, we propose to treat scaphoid nonunions with (a) arthroscopic-assisted reduction and internal fixation (AASSIF) and adding (b) metaphyseal core decompression of the distal radius (MCDDR) in advanced stages, without bone graft. Material and Methods: We evaluated retrospectively 48 patients with scaphoid nonunions treated prospectively by (AASSIF) with (MCDDR) in 48 cases. The average age was 30.63 years. The right side was affected in 31 patients, and 79.7% corresponded to the dominant extremity. The mean time from injury to surgery was 22.93 months. The nonunions were grouped according to the Slade-Dodds classification. Results: Scaphoid union was obtained in 44 patients, 4 patients failed to obtain healing. One patient decided to not be operated again, because of the lack of symptoms. Three required a new surgical procedure 9 months later. In 2 patients, the failures were by improper placement of the screw, although these patients had no symptoms. In cystic and/or magnitude bone nonunion defects with large zones of necrosis, defect filling was observed, even in those cases in which the loss of bone stock exceeded 10 mm. The biological effect of the metaphyseal decompression characterized by an increased hyperemia over the radial column was demonstrated with SPECT studies. The visual analogue scale showed an average of 1.04 (0-2) postoperative pain. The average postoperative range of function was 65.3° extension (range, 46° to 88°), 69.2° flexion (range, 55° to 88°), 10.7° radial deviation (range, 5° to 20°), and 26° ulnar deviation (range, 20° to 37°). The average Mayo score was 95 ± 6. Conclusion: We recommend arthroscopic-assisted internal fixation without bone grafting and core decompression of the distal radius for young or middle-aged nonsmoking patients with scaphoid nonunions including cystic and deformed types, typical of advanced stages. The method is not recommended for nonunions with significant sclerosis or in those with a very small proximal fragment in which solid screw fixation would be questionable.