Bone grafting for scaphoid nonunion surgery

Abstract

Aims The purpose of this systematic review was to determine the rates of union for vascularized versus non-vascularized grafting techniques in the operative management of scaphoid nonunion. Secondary aims were to determine the effect of the fixation techniques used, the source of grafting, as well as the influence of fracture location (proximal pole) and avascular necrosis (AVN). Methods A search of PubMed, MEDLINE, and Embase was performed in June 2021 using the Preferred Reporting Items for Systematic Review and Meta-Analyses statement and registered using the PROSPERO International prospective register of systematic reviews. The primary outcome was union rate. Results There were 78 studies that met the inclusion criteria with a total of 7,671 patients (87.8% male, 12.2% female). The mean age was 27.9 years (SD 3.8) and the mean follow-up was 30.9 months (SD 25.9). The mean union rate was 88.7% (95% confidence interval (CI) 85.0 to 92.5) for non-vascularized grafts versus 87.5% (95% CI 82.8 to 92.2) for vascularized grafts (p = 0.685). Pooled analysis of trial data alone found a mean union rate of 82.4% (95% CI 66.9% to 97.9%) for non-vascularized grafts and 89.4% (95% CI 84.1% to 94.7%) for vascularized grafts (p = 0.780). No significant difference was observed in union rates between any of the fixation techniques used in the studies (p = 0.502). Distal radius and iliac crest graft source had comparable mean union rates (86.9% (95% CI 83.1 to 90.7) vs 87.6% (95% CI 82.2 to 92.9); p = 0.841). Studies that excluded patients with both proximal pole fractures and AVN (n = 14) had a mean union rate of 96.5% (95% CI 94.2 to 98.9) that was significantly greater than the mean union rate of 86.8% (95% CI 83.2 to 90.4) observed in the remaining studies (p < 0.001). Conclusion Current evidence suggests vascularized bone grafting does not yield significantly superior results to non-vascularized grafting in scaphoid nonunion management. However, potential selection bias lessens the certainty of these findings. The fixation type or source of the graft used was not found to influence union rates either. Sufficiently designed and powered prospective randomized controlled trials in this area are needed. Cite this article: Bone Joint J 2022;104-B(5):549–558.

Surgical Treatment of Scaphoid Fractures: Recommendations for Management

“…33 Although a comparison of several VBGs in the literature have demonstrated union rates from 86 to 94%, 34 other reviews of studies have cast doubt on clear superiority in union rates and functional outcomes of VBGs over NVBGs. [35][36][37][38] Volar flexion (humpback) deformity is usually associated with significant bone loss and malalignment leading to dorsal intercalated segment instability (DISI), which requires correction to decrease pain, increase wrist mobility, facilitate union, and arrest progression to arthritis. 39 Furthermore, the presence of DISI can pose a risk of failure to VBGs.…”

Vascularized pronator quadratus pedicled bone grafting versus iliac crest bone grafting in the treatment of scaphoid nonunion: a retrospective study

“…Duncumb et al 11 performed a systematic review and meta-analysis to compare the union rate of vascularized versus non-vascularized bone grafting in the treatment of scaphoid nonunion. Seventy-eight studies, including 7,671 patients, were included in their analysis.…”

“…Duncumb et al 11 reported a pooled nonunion rate of almost 10% for vascularized bone grafts in the treatment of scaphoid nonunion. Using this nonunion rate, power of 90%, and absolute error of 0.1, a number of 35 patients was identified as enough to perform this cohort study.…”

What’s New in Orthopaedic Trauma

“…The fixation technique and type of graft also did not influence union rates. However, multiple studies excluded patients with proximal pole fractures and those with osteonecrosis; these studies showed significantly higher mean union rates (96.5%) than in the remaining studies (86.8%), suggesting bias and lowering the certainty of the results 10 .…”