Novel MRI-based vertebral bone quality score as a predictor of cage subsidence following transforaminal lumbar interbody fusion

Abstract

OBJECTIVE Decreased bone mineral density as measured by dual-energy x-ray absorptiometry (DEXA) has been reported to be associated with cage subsidence following transforaminal lumbar interbody fusion (TLIF). However, DEXA is not often available or routinely performed before surgery. A novel MRI-based vertebral bone quality (VBQ) score has been developed and reported to be correlated with DEXA T-scores. The authors investigated the ability of the VBQ score to predict cage subsidence and other risk factors associated with this complication. METHODS In this retrospective study, the authors reviewed the records of patients who had undergone single-level TLIF from March 2014 to October 2015 and had a follow-up of more than 2 years. Cage subsidence was measured as postoperative disc height loss and was graded according to the system proposed by Marchi et al. The MRI-based VBQ score was measured on T1-weighted images. Univariable analysis and multivariable binary logistic regression analysis were performed. Ad hoc analysis with receiver operating characteristic curve analysis was performed to assess the predictive ability of the significant continuous variables. Additional analyses were used to determine the correlations between the VBQ score and T-scores and between the significant continuous variables and the amount of cage subsidence. RESULTS Among 242 patients eligible for study inclusion, 111 (45.87%) had cage subsidence after the index operation. Multivariable logistic regression analyses demonstrated that an increased VBQ score (OR 14.615 ± 0.377, p < 0.001), decreased depth ratio (OR 0.011 ± 1.796, p = 0.013), and the use of kidney-shaped cages instead of bullet-shaped cages (OR 2.766 ± 0.358, p = 0.008) were associated with increased cage subsidence. The VBQ score was shown to significantly predict cage subsidence with an accuracy of 85.6%. The VBQ score was found to be moderately correlated with DEXA T-scores of the total hip (r = −0.540, p < 0.001) and the lumbar spine (r = −0.546, p < 0.001). The amount of cage subsidence was moderately correlated with the VBQ score (r = 0.512, p < 0.001). CONCLUSIONS Increased VBQ scores, posteriorly placed cages, and kidney-shaped cages were risk factors for cage subsidence. The VBQ score was shown to be a good predictor of cage subsidence, was moderately correlated with DEXA T-scores for the total hip and lumbar spine, and also had a moderate correlation with the amount of cage subsidence.

Vertebral bone quality score to predict cage subsidence following oblique lumbar interbody fusion

“…Owing to the easy-to-teach methodology and rapid results unaffected by confounding factors, the measurement of this score has shown good reproducibility and reliability, demonstrating that this is a practical tool for clinical use [ 14 , 38 ]. In previous studies, the use of the VBQ score was verified against the use of DEXA to identify osteoporotic bone and to independently predict the risk of fragility fractures, cage subsidence, and vertebral compression fracture in patients with spine metastases [ 13 , 39 , 40 ]. In the present study, the VBQ score was moderately correlated with the average lumbar DEXA T-score and amount of cage subsidence.…”

“…This score was found to significantly correlate with BMD assessed using the DEXA scan, which may help reduce investigation costs and radiation hazards [ 11 , 12 ]. Moreover, the VBQ score has been recognized as an independent risk factor for fragility fractures, and it predicts the occurrence of cage subsidence and reoperation after transforaminal lumbar interbody fusion surgery [ 13 , 14 ].…”

A Novel Cervical Vertebral Bone Quality Score Independently Predicts Cage Subsidence After Anterior Cervical Diskectomy and Fusion

“…C7 was not included in the equation because of its substantially larger size, the increase in its vertical orientation, and its smaller range of movements in comparison with C3 through C6, making it anatomically different than the typical cervical vertebra and our calculation less homogenous. 56 Given that MRI is often the imaging modality of choice before ACDF and the lack of access to DEXA T-scores, the new C-VBQ scoring system could be an ideal alternative for surgeons to assess patients' bone mineral density and risk of subsidence using routine imaging.…”

The Association between High Preoperative MRI‐based Vertebral Bone Quality (VBQ) Score and Titanium Mesh Cage Subsidence after Anterior Cervical Corpectomy and Fusion

“…9 A new MRI-based vertebral bone quality (VBQ) score has emerged as an alternative to dual-energy X-ray absorptiometry (DEXA) for measuring BMD. [16][17][18][19] Recently, the MRIbased vertebral bone quality (VBQ) score has been shown to correlate with HU value, DEXA T-score and predict osteoporotic fractures. 18 Higher VBQ scores have been shown to be a risk factor for cage subsidence and reoperation after lumbar fusion.…”

“…18 Higher VBQ scores have been shown to be a risk factor for cage subsidence and reoperation after lumbar fusion. 16,17 As far as we know, no previous research has evaluated the association of VBQ score with TMC subsidence after ACCF.…”