Rod Fracture After Apparently Solid Radiographic Fusion in Adult Spinal Deformity Patients.

Journal Article (Journal Article;Multicenter Study)

BACKGROUND: Rod fracture occurs with delayed fusion or pseudarthrosis after adult spinal deformity (ASD) surgery. Rod fracture after apparent radiographic fusion has not been previously investigated. METHODS: Patients with ASD in a multicenter database were assessed for radiographic fusion by a committee of 3 spinal deformity surgeons. Fusions were rated as bilaterally fused (A), unilaterally fused (B), partially fused (C), or not fused (D). Patients with grade A or B fusion and 2-year follow-up were included. Patients with radiographic fusion were evaluated for subsequent rod fracture. Adjusted analyses were conducted with multiple logistic regression, using backwards-variable selection to a threshold of P < 0.2, to assess for associated factors. RESULTS: Of 402 patients with radiographically apparent solid fusion, 9.5% (38) subsequently suffered a broken rod. On multivariate analysis, greater rates of rod fracture were seen among patients of age group 60-69 years (vs. 18-49), body mass index 30-34 and 35+ (vs. <25), stainless-steel rods (vs. titanium), patients with rods ≤5.5 mm (vs. 6.35 mm), and patients with Charlson score 0 (vs. 3+). Of the 38 patients with rod fractures, 18 (47.4%) presented with worsened pain, and 8 (21.1%) required revision at minimum 2-year follow-up. CONCLUSIONS: Rod fracture occurred in 9.5% of patients with apparently solid radiographic fusion after ASD surgery. Advanced age, obesity, small diameter rods (5.5 mm), osteotomy, and lower comorbidity burden were significantly associated with rod fracture. Nearly one-half of these patients noted worsening pain, and 21.1% required revision surgery. Instrumentation failure may occur and may be symptomatic even in the setting of apparent fusion on plain radiographs.

Full Text

Duke Authors

Cited Authors

  • Daniels, AH; DePasse, JM; Durand, W; Hamilton, DK; Passias, P; Kim, HJ; Protopsaltis, T; Reid, DBC; LaFage, V; Smith, JS; Shaffrey, C; Gupta, M; Klineberg, E; Schwab, F; Burton, D; Bess, S; Ames, C; Hart, RA; International Spine Study Group,

Published Date

  • September 2018

Published In

Volume / Issue

  • 117 /

Start / End Page

  • e530 - e537

PubMed ID

  • 29929025

Electronic International Standard Serial Number (EISSN)

  • 1878-8769

Digital Object Identifier (DOI)

  • 10.1016/j.wneu.2018.06.071


  • eng

Conference Location

  • United States