Urinary N-Telopeptide Can Predict Pseudarthrosis After Anterior Cervical Decompression and Fusion

Abstract

Study Design. Prospective cohort study. Objective. To examine preoperative urinary cross-linked n-telopeptide (uNTx) and assess for association with fusion rates in patients undergoing single and multi-level anterior cervical decompression and fusion (ACDF). Summary of Background Data. Although high rates of fusion have been reported for ACDF, the risk of pseudarthrosis remains substantial. An established marker of bone turnover, uNTx may prove useful as a predictor of fusion. Methods. Patients undergoing primary ACDF with allograft/plating technique from 2015 to 2017 by a single surgeon were consecutively enrolled and preoperative uNTx was collected. Patients undergoing revision, with creatinine >1.2, and with improperly-collected uNTx were excluded. Demographics, laboratory values, and fusion status were assessed at 6 months, 1 year, and 2 years postoperatively. Results. Of the 97 patients enrolled, 69 met inclusion criteria. Of included cases, 41%, 33%, 18%, and 8% underwent 1-, 2-, 3-, and 4-level ACDF, respectively. Overall, fusion rates were 37.3%, 70.9%, and 95.3% at 6 months, 1 year, and 2 years, respectively. uNTx was higher in the fusion group (31.1 vs. 22.2, P = 0.001) at 6 months and 1 year (30.0 vs. 21.0, P = 0.006), with no difference at 2 years. No differences were identified in the proportion of smokers, immunomodulatory agents, corpectomies, or fusion levels between groups. Multivariate regression analysis demonstrated that uNTx is an independent predictor of fusion (odds ratio, OR, 1.124, P = 0.003). Both groups experienced improvements in NDI and VAS neck pain at 6 months with no significant differences noted between groups. Of 16 patients with pseudarthrosis at 1 year, 2 underwent posterior cervical fusion for symptoms. Conclusion. Preoperative uNTx was greater in patients with successful ACDF fusion compared with patients with pseudarthrosis at 6 months and 1 year. A negative correlation was found between preoperative uNTx and motion on dynamic imaging. These results suggest that uNTx could serve to identify patients at risk for pseudarthrosis after ACDF. Level of Evidence: 3

PEEK interbody devices for multilevel anterior cervical discectomy and fusion: association with more than 6-fold higher rates of pseudarthrosis compared to structural allograft

“…9 The risk of nonunion is especially prevalent in multiple-level procedures and has been reported to result in significantly higher Neck Disability Index (NDI) scores and lower rates of improvement in neck pain. 22 This increased likelihood of pseudarthrosis with the use of PEEK was reflected in the cohort we describe as rates of pseudarthrosis increased by 23% in the PEEK group and 1% in the allograft group compared with the rates in our previous study on singlelevel ACDF procedures.…”

Outcomes of Revision Surgery for Pseudarthrosis After Anterior Cervical Fusion: Case Series and Systematic Review

“…17,20,21 Multiple strategies have been employed to treat symptomatic pseudarthrosis, including anterior, posterior, or circumferential approaches, and attempts have been made to identify those at highest risk before surgery. 22 There has been some debate in the literature regarding which of these treatments is most effective, 11,23 yet there is a paucity of data to support any given approach, as the majority of studies available do not report standardized outcomes and often lack the power necessary to draw generalizable conclusions about the superiority of one approach over another.…”

Risk Factors of Nonfusion after Anterior Cervical Decompression and Fusion in the Early Postoperative Period: A Retrospective Study

“…First, this is a retrospective and single‐center analysis of suspected risk factors, and the sample size was small. Second, in previous studies, 13 , 19 , 49 patients’ serum was collected before surgery to explore the predictors of postoperative fusion. However, bone turnover markers, hormone levels, and serum calcium levels can change over time.…”

“… 13 , 14 Several studies have tried to predict which patients are at higher risk of nonfusion after ACDF and which factors could lead to nonfusion. For example, smoking, diabetes, osteoporosis, 15 , 16 , 17 and preoperative radiographic markers of bone turnover 18 , 19 are predictors of nonfusion following ACDF.…”