Friday, September 28, 2018 10:30 AM–12:00 PM abstracts: complications of cervical spine surgery: 162. Urinary N-telopeptide can predict pseudarthrosis after anterior cervical decompression and fusion (ACDF): a prospective study

Abstract

BACKGROUND CONTEXT Anterior cervical decompression and fusion (ACDF) is one of the most successful and widely performed spine surgeries. Although high rates of fusion have been reported, there is a risk for pseudarthrosis. Urinary cross-linked n-telopeptide of type I collagen (uNTx), is an important marker of bone turnover and may prove useful as a predictor of fusion in pts undergoing ACDF. PURPOSE The purpose of present study was to examine the association of preop uNTx level and successful fusion after ACDF. STUDY DESIGN/SETTING Prospective cohort study. PATIENT SAMPLE Adult patients who underwent ACDF with allograft and plating technique. OUTCOME MEASURES Fusion status was assessed using radiographic criteria published by Song et al. METHODS Patients undergoing primary ACDF with allograft and plating technique from 2015 to 2017 by a single surgeon were consecutively enrolled and preop uNTx was measured. Revision cases, improperly timed uNTx collection, pts with a Cr>1.2 were excluded. Demographics, operative, laboratory and fusion data was assessed at 6 months, 1 year and 2 years. NDI and VAS outcome scores were compared between fusion and nonfusion groups. Regression analysis was performed to assess the association of preop uNTx and successful fusion. RESULTS Of the 97 patients enrolled, 67 met inclusion criteria and were studied. 41%, 33%, 18% and 8% underwent one, two, three and four level ACDFs, respectively. Fusion rates were 37.3% at 6 months (n=67), 70.9% at 1 year (n=55) and 95.3% at 2 years (n=43). The preop uNTx was higher in the fusion group at 6mo (31 vs. 22, p CONCLUSIONS Urinary NTx was higher in patients with successful ACDF fusion compared to patients with radiographic pseudarthrosis at 6 months and 1 year. A linear relationship between uNTx levels and Fusion was observed. Surgeons should consider measuring uNTx prior to cervical fusion procedures to identify patients at risk for pseudarthrosis.