Cervical vertebral Hounsfield units are a better predictor of Zero-P subsidence than the T-score of DXA in patients following single-level anterior cervical discectomy and fusion with zero-profile anchored spacer

• Published in: European spine journal Vol. 33; no. 1; pp. 216 - 223
• Main Authors: Pu, Hong-yu, Song, Xun-zhou, Wang, Bo, Wei, Peng, Zeng, Rui, Chen, Qian
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 2024; Springer Nature B.V
• Subjects: Absorptiometry, Photon - methods; Back surgery; Computed tomography; Diskectomy; Dual energy X-ray absorptiometry; Hospitals; Humans; Lumbar Vertebrae; Medicine; Medicine & Public Health; Methods; Neurosurgery; Original Article; Orthopedics; Patients; Retrospective Studies; Risk factors; ROC Curve; Spinal Fusion - methods; Spondylosis; Spondylosis - diagnostic imaging; Spondylosis - surgery; Subsidence; Surgical Orthopedics; Tomography; Tomography, X-Ray Computed - methods; Vertebrae; score; Dual-energy X-ray absorptiometry; Subsidence; Hounsfield units; Zero-profile; Anterior cervical discectomy and fusion; T-score
• ISSN: 0940-6719; 1432-0932; 1432-0932
• DOI: 10.1007/s00586-023-07934-8

Objectives
To determine the predictive effect of Hounsfield unit (HU) values in the cervical vertebral body measured by computed tomography (CT) and
T
-scores measured by dual-energy X-ray absorptiometry (DXA) on Zero-P subsidence after anterior cervical discectomy and fusion (ACDF)with Zero-P. In addition, we evaluated the most reliable measurement of cervical HU values.
Methods
We reviewed 76 patients who underwent single-level Zero-P fusion for cervical spondylosis. HU values were measured on CT images according to previous studies. Univariate analysis was used to screen the influencing factors of Zero-P subsidence, and then, logistic regression was used to determine the independent risk factors. The area under the receiver operating characteristic curve (AUC) was used to evaluate the ability to predict Zero-P subsidence.
Results
Twelve patients (15.8%) developed Zero-P subsidence. There were significant differences between subsidence group and non-subsidence group in terms of age, axial HU value, and HU value of midsagittal, midcoronal, and midaxial (MSCD), but there were no significant differences in lowest
T
-score and lowest BMD. The axial HU value (OR = 0.925) and HU value of MSCD (OR = 0.892) were independent risk factors for Zero-P subsidence, and the lowest
T
-score was not (OR = 1.186). The AUC of predicting Zero-P subsidence was 0.798 for axial HU value, 0.861 for HU value of MSCD, and 0.656 for
T
-score.
Conclusions
Lower cervical HU value indicates a higher risk of subsidence in patients following Zero-P fusion for single-level cervical spondylosis. HU values were better predictors of Zero-P subsidence than DXA
T
-scores. In addition, the measurement of HU value in the midsagittal, midcoronal, and midaxial planes of the cervical vertebral body provides an effective method for predicting Zero-P subsidence.