Patient physiology influences the MRI-based vertebral bone quality score

BACKGROUND CONTEXTOsteoporosis is a critical issue affecting postmenopausal women and the aging population. A novel magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score has been proposed as a method to identify poor bone quality and predict fragility fractures. The diagnostic accuracy of this tool is not well understood.PURPOSETo examine the ability of VBQ to predict osteoporosis and osteopenia, its correlation with dual-energy x-ray absorptiometry (DEXA), and the influence of patient-specific factors upon the score.STUDY DESIGNRetrospective cohort study.PATIENT SAMPLEPatients over the age of 18 with a DEXA scan and noncontrast, T1-weighted MRI of the lumbar spine completed within a 2-year period.OUTCOME MEASURESArea-under-curve (AUC) values of the VBQ score predicting osteopenia and osteoporosis when controlling for patient characteristics.METHODSPatients with noncontrast, T1-weighted MRIs of the lumbar spine and DEXA scans completed within a 2-year time frame were retrospectively reviewed. Patient demographics and medical risk factors for osteoporosis were identified and compared. VBQ scores were measured by two trained researchers and interrater reliability was calculated. Patients were separated into three groups defined by lowest DEXA T-score: Healthy Bone, Osteopenia, and Osteoporosis. analysis of variance, Kruskal-Wallis test, chi-square, t tests, Mann-Whitney U tests, and multivariate linear regression were performed to examine the relationship between patient characteristics, DEXA t-scores, and VBQ scores. Receiver operating characteristic analysis and AUC values were generated for the prediction of osteopenia and osteoporosis.RESULTSA total of 156 patients were included for analysis. Sufficient inter-rater reliability was determined for VBQ measures (intraclass correlation coefficient: 0.81). Most patients were female (83%), postmenopausal (81%), and had hyperlipidemia (64%). Patients with hyperlipidemia and healthy bone density by DEXA had elevated baseline VBQ scores (p<.001) reflective of values seen in osteopenia and osteoporosis. The AUC of the VBQ score predicting osteopenia and osteoporosis changed to be more concordant with DEXA results after controlling for hyperlipidemia (AUC=0.72, 0.70 vs. AUC=0.88, 0.89; p<.001). Sub-analysis of hyperlipidemia subtypes revealed that elevated high-density lipoprotein is associated with elevated VBQ scores.CONCLUSIONSHyperlipidemia increased the MRI-based VBQ score in our healthy bone population. The high signal intensities resembled values seen in osteopenia and osteoporosis, suggesting that physiologic variables which impact bone composition may influence the VBQ score. Specifically, elevated high-density lipoprotein may contribute to this. The microarchitectural changes and the clinical implications of these factors need further exploration.     

MRI-based vertebral bone quality score effectively reflects bone quality in patients with osteoporotic vertebral compressive fractures

Objective

The present study is aimed to validate the ability of the vertebral bone quality (VBQ) score to evaluate bone quality in patients with osteoporotic vertebral compression fractures (OVCF) and to compare it with the ability of T-score by DXA. In addition, the sensitivity of VBQ score with cerebrospinal fluid (CSF) of L2 and L3 segments as baseline is evaluated.

Methods

196 inpatients were collected and assigned into OVCF and Non-OVCF groups, respectively. For each patient, the VBQ score was calculated by the signal intensity of the L1–L4 vertebral bodies and CSF at L3 or L2 level from T1-weighted MRIs, while T-score from DXA was also obtained. The VBQ and T-score was compared between OVCF and non-OVCF groups, and among age groups. The OVCF ORs by VBQ score and T-score were calculated using logistic regression.

Results

OVCF group was significantly different to the non-OVCF group in the T-score (− 2.9 vs. − 0.7) and VBQ score (4.0 vs. 3.5). VBQ score and T-score in patient aged 60–79 years old could indicate the bone quality, but only T-score in patients aged 50–59 years old. OVCF are associated with both higher VBQ score and lower T-score. The VBQ scores calculated by L2 CSF and L3 CSF were similar.

Conclusions

The VBQ score is an effective indicator of bone quality in OVCF patients and comparable to T-score, particularly in people over 60 years old. The VBQ score is not sensitive to CSF of different segments as a baseline.

     

Vertebral bone quality score independently predicts cage subsidence following transforaminal lumbar interbody fusion

BACKGROUND CONTEXTCage subsidence following transforaminal lumbar interbody fusion (TLIF) has been associated with poor bone quality. Current evidence suggests that the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score correlates with poor bone quality.PURPOSETo our knowledge, this is the first study to assess whether the VBQ score can predict the occurrence of postoperative cage subsidence after TLIF surgery.DESIGN/SETTINGRetrospective single-center cohort.PATIENT SAMPLEPatients undergoing single-level TLIF for degenerative spine disease between February 2014 and October 2021.OUTCOME MEASURESExtent of subsidence.METHODSDemographic, procedure-related, and radiographic data were collected for study patients. VBQ scores were determined from preoperative T1-weighted MRI. Subsidence was defined as ≥2 mm of migration of the cage into the superior or inferior end plate or both. Univariate and multivariate logistic regression were used to determine the correlation between potential risk factors for subsidence and actual subsidence rates.RESULTSSubsidence was observed among 42 of the 74 study patients. The mean VBQ scores were 2.9±0.5 for patients with subsidence and 2.5±0.5 for patients without subsidence. The difference among groups was significant (p=.003). On multivariate logistic regression, a higher VBQ score was significantly associated with an increased risk of subsidence (OR=1.5, 95% CI=1.160–1.973, p=.004) and was the only significant independent predictor of subsidence after TLIF.CONCLUSIONWe found that a higher VBQ score was significantly associated with cage subsidence following TLIF. The MRI-VBQ score may be a valuable tool for assisting in identifying patients at risk of cage subsidence following TLIF.     

Preoperative MRI-based vertebral bone quality (VBQ) score assessment in patients undergoing lumbar spinal fusion

BACKGROUND CONTEXTThe importance of bone status assessment in spine surgery is well recognized. The current gold standard for assessing bone mineral density is dual-energy X-ray absorptiometry (DEXA). However, DEXA has been shown to overestimate BMD in patients with spinal degenerative disease and obesity. Consequently, alternative radiographic measurements using data routinely gathered during preoperative evaluation have been explored for the evaluation of bone quality and fracture risk. Opportunistic quantitative computed tomography (QCT) and more recently, the MRI-based vertebral bone quality (VBQ) score, have both been shown to correlate with DEXA T-scores and predict osteoporotic fractures. However, to date the direct association between VBQ and QCT has not been studied.PURPOSEThe objective of this study was to evaluate the correlation between VBQ and spine QCT BMD measurements and assess whether the recently described novel VBQ score can predict the presence of osteopenia/osteoporosis diagnosed with QCT.STUDY DESIGN/SETTINGCross-sectional study using retrospectively collected data.PATIENT SAMPLEPatients undergoing lumbar fusion from 2014-2019 at a single, academic institution with available preoperative lumbar CT and T1-weighted MRIs were included.OUTCOME MEASURESCorrelation of the VBQ score with BMD measured by QCT, and association between VBQ score and presence of osteopenia/osteoporosis.METHODSAsynchronous QCT measurements were performed. The average L1-L2 BMD was calculated and patients were categorized as either normal BMD (>120 mg/cm³) or osteopenic/osteoporotic (≤120 mg/cm³). The VBQ score was calculated by dividing the median signal intensity of the L1-L4 vertebral bodies by the signal intensity of the cerebrospinal fluid on midsagittal T1-weighted MRI images. Inter-observer reliability testing of the VBQ measurements was performed. Demographic data and the VBQ score were compared between the normal and osteopenic/osteoporotic group. To determine the area-under-curve (AUC) of the VBQ score as a predictor of osteopenia/osteoporosis receiver operating characteristic (ROC) analysis was performed. VBQ scores were compared with QCT BMD using the Pearson's correlation.RESULTSA total of 198 patients (53% female) were included. The mean age was 62 years and the mean BMI was 28.2 kg/m². The inter-observer reliability of the VBQ measurements was excellent (ICC of 0.90). When comparing the patients with normal QCT BMD to those with osteopenia/osteoporosis, the patients with osteopenia/osteoporosis were significantly older (64.9 vs. 56.7 years, p<.0001). The osteopenic/osteoporotic group had significantly higher VBQ scores (2.6 vs. 2.2, p<.0001). The VBQ score showed a statistically significant negative correlation with QCT BMD (correlation coefficient = -0.358, 95% CI -0.473 - -0.23, p<.001). Using a VBQ score cutoff value of 2.388, the categorical VBQ score yielded a sensitivity of 74.3% and a specificity of 57.0% with an AUC of 0.7079 to differentiate patients with osteopenia/osteoporosis and with normal BMD.CONCLUSIONSWe found that the VBQ score showed moderate diagnostic ability to differentiate patients with normal BMD versus osteopenic/osteoporotic BMD based on QCT. VBQ may be an interesting adjunct to clinically performed bone density measurements in the future.     

Assessment of bone density using the 1.5 T or 3.0 T MRI-based vertebral bone quality score in older patients undergoing spine surgery: does field strength matter?

BACKGROUND CONTEXTRecently published studies have revealed a correlation between MRI-based vertebral bone quality (VBQ) score and bone mineral density (BMD) measured using dual X-ray absorptiometry (DXA) or quantitative computed tomography (QCT). However, no studies have determined if differences in field strength (1.5 vs 3.0 T) could affect the comparability of the VBQ score among different individuals.PURPOSETo compare the VBQ score obtained from 1.5 T and 3.0 T MRI (VBQ_1.5T vs VBQ_3.0T) in patients undergoing spine surgery and assess the predictive performance of VBQ for osteoporosis and osteoporotic vertebral fracture (VCF).DESIGNA nested case‒control study based on an ongoing prospective cohort study of patients undergoing spine surgery.PATIENT SAMPLEAll older patients (men aged >60 years and postmenopausal women) with available DXA, QCT and MR images within 1 month were included.OUTCOME MEASURESVBQ score, DXA T-score, and QCT derived vBMD.METHODSThe osteoporotic classifications recommended by the World Health Organization and American College of Radiology were used to categorize the DXA T-score and QCT-derived BMD, respectively. For each patient, the VBQ score was calculated using T1-weighted MR images. Correlation analysis between VBQ and DXA/QCT was performed. Receiver operating characteristic (ROC) curve analysis, including determination of the area under the curve (AUC), was performed to assess the predictive performance of VBQ for osteoporosis.ResultsA total of 452 patients (98 men aged >60 years and 354 postmenopausal women) were included in the analysis. Across different BMD categories, the correlation coefficients between the VBQ score and BMD ranged from -0.211 to -0.511, and the VBQ_1.5T score and QCT BMD demonstrated the strongest correlation. The VBQ score was a significant classifier of osteoporosis detected by either DXA or QCT, with VBQ_1.5T showing the highest discriminative power for QCT-osteoporosis (AUC=0.744, 95% CI=0.685–0.803). In ROC analysis, the VBQ_1.5T threshold values ranged from 3.705 to 3.835 with a sensitivity between 48% and 55.6% and a specificity between 70.8% and 74.8%, while the VBQ_3.0T threshold values ranged from 2.59 to 2.605 with a sensitivity between 57.6% and 67.1% and a specificity between 67.8% and 69.7%.CONCLUSIONSVBQ_1.5T exhibited better discriminability between patients with and without osteoporosis than VBQ_3.0T. Considering the non-negligible difference in osteoporosis diagnosis threshold values between the VBQ_1.5T and VBQ_3.0T scores, it is essential to clearly distinguish the magnetic field strength when assessing the VBQ score.     

Novel MRI-based score for assessment of bone density in operative spine patients

BackgroundGood bone quality is key in avoiding a multitude of afflictions, including osteoporotic fragility fractures and poor outcomes after spine surgery. In patients undergoing instrumented spine fusion, bone quality often dictates screw pullout strength, insertional torque, and vertebral body loading properties. While dual-energy X-ray absorptiometry (DEXA) screening is the current method of assessing bone mineral density, the majority of patients do not have DEXA measurements available before undergoing surgical instrumentation.PurposeTo create a simple magnetic resonance imaging (MRI)-based score to evaluate bone quality and evaluate the degree to which it correlates with conventional DEXA scores.Study Design/SettingRetrospective cohort.Patient SamplePatients ≥18 years of age undergoing spine surgery for degenerative conditions between 2013 and 2018.Outcome MeasuresCorrelation of the vertebral bone quality (VBQ) score with DEXA T-scores, and association between VBQ score and presence of osteopenia/osteoporosis.MethodsUsing noncontrast T1-weighted MRIs of the lumbar spine, the novel VBQ score was calculated for each patient. DEXA T-scores of the femoral neck and total hip were obtained and were compared with patient VBQ scores using linear regression and Pearson's correlation.ResultsAmong 68 patients included in this study, 37 were found to have osteopenia/osteoporosis (T-score < −1.0) based on DEXA. A greater VBQ score was significantly associated with the presence of osteopenia/osteoporosis with a predictive accuracy of 81%. VBQ scores correlated moderately with femoral neck T-scores, the lowest overall T-scores of each patient, and correlated fairly with total hip T-scores.ConclusionsThis is the first study to correlate the novel VBQ score obtained from MRIs with DEXA T-score. We found this score to be a significant predictor of healthy versus osteopenic/osteoporotic bone with an accuracy of 81%, and found that VBQ score was moderately correlated with femoral neck and overall lowest T-score.     

Bone quality in patients with osteoporosis undergoing lumbar fusion surgery: analysis of the MRI-based vertebral bone quality score and the bone microstructure derived from microcomputed tomography

BACKGROUND CONTEXTOsteoporosis is a risk factor for instrumentation failure in spine surgery. Bone strength is commonly assessed by bone mineral density (BMD) as a surrogate marker. However, BMD represents only a portion of bone strength and does not capture the qualitative dimensions of bone. Recently, the magnetic resonance imaging (MRI)-based vertebral bone quality (VBQ) score was introduced as a novel marker of bone quality. However, it is still unclear if the VBQ score correlates with in-vivo bone microstructure.PURPOSEThe aims of the study were (1) to demonstrate differences in MRI-based (VBQ) and in-vivo (microcomputed tomography; μCT) bone quality between osteopenic/osteoporotic and normal bone, (2) to show the correlation between VBQ, bone microstructure and volumetric BMD (vBMD), and (3) to determine the predictive value of the VBQ score for the prevalence of osteopenia/osteoporosis.STUDY DESIGN/SETTINGRetrospective cross-sectional study.PATIENT SAMPLE267 patients who underwent posterior lumbar fusion surgery from 2014 to 2021 at a single academic institution. Bone biopsies were harvested intraoperatively in 118 patients.OUTCOME MEASURESVBMD, VBQ score, and bone microstructure parameters derived from μCT.METHODSQuantitative computed tomography (QCT) measurements were performed at the lumbar spine and the L1/L2 average was used to categorize patients with a vBMD ≤120mg/cm³ as osteopenic/osteoporotic. The VBQ score was determined by dividing the median signal intensity of the L1–L4 vertebrae by the signal intensity of the cerebrospinal fluid using sagittal T1-weighted MRI scans. Intraoperative bone biopsies from the posterior superior iliac spine were obtained and evaluated with μCT. VBQ scores and μCT parameters were compared between the normal and the osteopenic/osteoporotic group. Correlations between VBQ score, μCT parameters and vBMD were assessed with Spearman's correlation (ρ). Receiver operating characteristic (ROC) analysis was performed to determine the VBQ score as a predictor for osteopenia/osteoporosis. Multiple linear regression analysis with vBMD L1/L2 as outcome was used to identify independent predictors from VBQ, μCT parameters and demographics.RESULTS267 patients (55.8% female, age 63.3 years, BMI 29.7 kg/m²; n=118 with bone biopsy) with a prevalence of osteopenia/osteoporosis of 65.2% were analyzed. In the osteopenic/osteoporotic group the VBQ score, structured model index (SMI), and trabecular separation (Tb.Sp) were significantly higher, whereas bone volume fraction (BV/TV), connectivity density (Conn.D) and trabecular number (Tb.N) were significantly lower. There were significant correlations between VBQ and μCT parameters ranging from ρ=-.387 to ρ=0.314 as well as between vBMD and μCT parameters ranging from ρ=-.425 to ρ=.421, and vBMD and VBQ (ρ=-.300, p<.001). ROC analysis discriminated osteopenia/osteoporosis with a sensitivity of 84.7% and a specificity of 40.6% at a VBQ score threshold value of 2.18. Age, BV/TV and trabecular thickness (Tb.Th), but not VBQ, were significant independent predictors for vBMD (corrected R²=0.434).CONCLUSIONSThis study demonstrated for the first time that the VBQ score is associated with trabecular microstructure determined by μCT. The bone microstructure and VBQ score were significantly different in patients with impaired vBMD. However, the ability to predict osteopenia/osteoporosis with the VBQ score was moderate. The VBQ score appears to reflect additional bone quality characteristics and might have a complementary role to vBMD. This enhances our understanding of the biological background of the radiographic VBQ score and might be a take-off point to evaluate the clinical utility of it as non-invasive screening tool for bone quality.     

The difference in spine specimen dual-energy X-ray absorptiometry bone mineral density between in situ and in vitro scans

Background contextHuman cadaveric specimens are commonly used to evaluate bone-implant interface strength in osteoporotic spine fixation. Dual-energy X-ray absorptiometry (DXA) scans are usually carried out on explanted spine specimens to measure bone mineral density (BMD) before in vitro biomechanical studies are carried out.PurposeThe purposes of this study were to verify and quantify the difference in DXA BMD between unexplanted (in situ) and explanted (in vitro) scans and to develop and validate a correction factor (CF) between in vitro and in situ DXA BMD.Study designThis is a retrospective analysis of past DXA scans of explanted specimens and a repeated measure scan rescan study of in situ and in vitro spine specimens.MethodsDual-energy X-ray absorptiometry scans were previously carried out on 106 male and 83 female lumbar specimens. Using multiple regressions, the correlation functions between Z score, BMD, and age were determined for male and female groups. The CF was developed based on difference in BMD between mean in vitro and population data. Next, in situ DXA scans were carried out on the lumbar spine of four full human cadavers, and subsequently, in vitro scans were repeated after explantation. The CF was applied to these in vitro scan data and the resulting corrected BMD compared with in situ scan values.ResultsThe specimens had significantly lower Z score than population mean. The mean Z score was ?0.7±1.4 (p<.001) for male and ?0.3±1.3 (p=.03) for female specimens. The difference between in situ and in vitro scans was quantified to be 0.06 g/cm² for male specimens and to be a function of age (6.80 Age^?0.5?3.76 Age^?0.365) for female specimens. In vitro BMD was 96±11% of in situ BMD and was significantly different (p=.04). Corrected BMD after application of CF was 97±11% of in situ BMD and was not significantly different (p=.13).ConclusionsIn vitro BMD scan on explanted specimens measured lower DXA values than in situ BMD scans on full cadavers. A CF when used resulted in more accurate measure of the in situ BMD.     

The impact of degenerative disc disease on regional volumetric bone mineral density (vBMD) measured by quantitative computed tomography

BACKGROUND CONTEXTIt has been reported that degenerative disc disease (DDD) is associated with higher spinal bone mineral density (BMD) based on previous studies that used dual X-ray absorptiometry (DXA). However, DDD is often associated with proliferative bone changes and can lead to an overestimation of BMD measured with DXA. Trabecular volumetric BMD (vBMD) in the vertebral body measured with quantitative computed tomography (QCT) is less affected by those changes and can be a favorable alternative to DXA for patients with degenerative spinal changes.PURPOSEThe purpose of this study is to investigate the effect of DDD on regional trabecular vBMDs in the vertebral body measured by QCT.STUDY DESIGN/SETTINGCross-sectional observational study at a single academic institution.PATIENTS SAMPLEConsecutive patients undergoing posterior lumbar spinal fusion between 2014 and 2017 who had a routine preoperative CT scan and magnetic resonance imaging (MRI) within a 90-day interval.OUTCOME MEASURESRegional trabecular vBMDs in the vertebral body by QCT.METHODSQCT measurements were conducted in L1–S1 vertebral trabecular bone. Any apparent sclerotic lesions that might affect vBMD values were excluded from the region of interest. The vBMDs of each level were defined as the average vBMD of the upper and lower vertebrae. To evaluate DDD, Pfirrmann grade, Modic grade, total end plate score, and vacuum phenomenon were documented. Univariate regression analysis and multivariate analyses with a linear mixed model adjusted with individual variability of segmental vBMDs were conducted with vBMD as the response variable.RESULTSOf 143 patients and 715 disc levels, 125 patients and 596 discs met our inclusion criteria. Mean vBMD (±standard deviation [SD]) of all levels was 119.0±39.6 mg/cm³. After adjusting for all covariates, Pfirrmann grade was not an independent contributor to vBMD, but the presence of any Modic change (type 1, β=6.8, p≤.001; type 2, β=6.7, p<.001; type 3, β=43.6, p<.001), high TEPS (score 10–12, β=14.2, p<.001), or vacuum phenomenon (β=9.0, p<.001) was shown to be independent contributors to vBMD.CONCLUSIONSOur results showed that the presence of certain end plate lesions (Modic changes and high TEPS) on MRI was significantly associated with increased regional QCT-vBMDs in the vertebral body, but no significant association was observed with disc nucleus pathology, unless it was associated with a vacuum phenomenon. When end plate lesions with Modic changes and high TEPS are present at the measuring level, care must be taken to interpret vBMD values, which might be overestimations even if the trabecular area appears normal.     

Socioeconomic disparities in the utilization of spine augmentation for patients with osteoporotic fractures: an analysis of National Inpatient Sample from 2011 to 2015

BACKGROUND CONTENTVertebral augmentation procedures are used for treatment of osteoporotic compression fractures. Prior studies have reported disparities in the treatment of patients with osteoporotic vertebral fractures, particularly with regards to the use of vertebroplasty and kyphoplasty.PURPOSEThe purpose of this study is to report updates in racial and health insurance inequalities of spine augmentation procedures in patients with osteoporotic fractures.METHODSWith the use of the National Inpatient Sample, we identified hospitalized patients with osteoporotic fractures between the period of 2011 and 2015. Patients with spine augmentation, defined by the utilization of vertebroplasty and kyphoplasty, were also identified. Our primary outcome was defined as the utilization of spine augmentation procedures across ethnic (white, hispanic, black, and asian/pacific islander) and insurance (self-pay, private insurance, Medicare, and Medicaid) groups. Variables were identified from the NIS database using International Classification of Diseases, Ninth and Tenth diagnosis codes. Univariate and multivariate regression analysis was used for statistical analysis with p value <.05 considered significant. A subgroup analysis was performed across the utilization of kyphoplasty, vertebroplasty, and Medicare coverage.RESULTSWe identified a total of 110,028 patients with a primary diagnosis of vertebral fracture between 2011 and 2015 (mean age: 74.4±13.6 years, 68% women). About 16,237 patients (14.8%) underwent any type of spine augmentation with over 75% of the patients receiving kyphoplasty. Multivariate analysis showed that black patients (odds ratio [OR]=0.64, 95% confidence interval [CI]: 0.58–0.70, p<.001), Hispanic patients (OR=0.79, 95% CI: 0.73–0.86, p<.001), and Asian/Pacific Islander (OR=0.79, 95% CI: 0.70–0.89, p<.001) had significantly lower odds for receiving any spine augmentation compared with white patients. Patients with Medicaid (OR=0.59, 95% CI: 0.53–0.66, p<.001), private insurance (OR=0.90, 95% CI: 0.85–0.96, p=.001), and those who self-pay (OR=0.57, 95% CI: 0.47–0.69, p<.001) had significantly lower odds of spine augmentation compared with those with Medicare. Comparative use of kyphoplasty was not significantly different between white and black patients (OR=0.85, 95% CI: 0.70–1.04, p=.12). However, Hispanic patients (OR=0.84, 95% CI: 0.71–0.99, p=.04) and Asian/Pacific Islander patients (OR=0.73, 95% CI: 0.58–0.92, p=.007) had significantly lower use of kyphoplasty compared with white patients. The comparative use of kyphoplasty among patients receiving spine augmentation was not significantly different across each insurances status when compared with patients with Medicare.CONCLUSIONSOur study suggests that racial and socioeconomic disparities continue to exist with the utilization of spine augmentation procedures in hospitalized patients with osteoporotic fractures.     

Quantitative ultrasound and dual-energy X-ray absorptiometry in the prediction of fragility fracture in men

Fragility fractures in men represent a major health problem, and this prompts a necessity for reliable tools for the identification of men at risk of fracture. In order to assess the ability of dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) in the prediction of fracture risk in men and whether their combination might be useful in a clinical setting, we studied 401 men (age range 45–82 years, mean 60.3±12.5), of whom 133 had osteoporotic fractures and 268 did not. In all subjects we measured bone mineral density at the lumbar spine (BMD-LS) and at the femur, calculating thereafter the standard femoral subregions: neck (BMD-FN), total hip (BMD-T), trochanter (BMD-TR), intertrochanter (BMD-ITR), and Wards triangle (BMD-W), by DXA. We also performed ultrasound parameters at the calcaneus: speed of sound (SOS), broadband ultrasound attenuation (BUA) and Stiffness, by Achilles plus, and at the phalanxes: amplitude dependent speed of sound (AD-SoS) and the parameters of the graphic trace: bone transmission time (BTT), fast wave amplitude (FWA), signal dynamic (SDy) and ultrasound bone profile index (UBPI), by Bone Profiler. All DXA and QUS parameters, apart from FWA, were significantly (P<0.001) lower in patients with a history of fracture. BMD at the proximal femur showed the best ability in discriminating men with or without fractures. QUS at the heel showed discriminatory ability significantly better than QUS at the fingers. By logistic regression analysis, adjusted for age and BMI, BMD-T showed the best association with fragility fracture [odds ratio (OR)=3.43, 95% confidence interval (CI)=2.47–4.77]. Among QUS parameters, the highest value of the OR was shown by stiffness (OR=3.18, CI=2.27–4.48). FWA and SDy were not associated with fragility fractures in men. If DXA and QUS were combined, the prediction of the OR of fragility fracture events in men increases; in fact Stiffness was able to increase the OR when added to BMD-LS (OR=5.44, CI=3.16–10.13) and BMD-T (OR=6.08, CI=2.63–14.27). SOS and BUA showed a similar pattern. AD-SoS improved the prediction of fracture only when combined with BMD-LS (OR=4.36, CI=1.99–9.57). If BMD-LS and BMD-FN or BMD-T were combined, the value of the OR increases (OR=4.59, CI=2.27–9.25 and OR=4.68, CI=2.24–9.76), respectively. Our study supports the effectiveness of QUS in the identification of osteoporotic fractures in men. QUS seems to play an independent and complementary role, with respect to DXA, in order to enhance the power for predicting osteoporotic fractures in men.     

Utility of fragility fracture prediction tools in a group of postmenopausal women

ObjectivesFractures are a common complication of osteoporosis. The main aim of our study was to assess the relation between fractures identified as low energy fractures (fragility), bone mineral density (BMD), trabecular bone score (TBS), and handgrip in a group of postmenopausal women. An additional aim was to determine the relation between fragility fractures and age, height loss, and falls (reported in the last 12 months and 5 years).Material and methodsThe study was conducted in a group of 120 (mean age 69 years; 59–81, SD 5.3) postmenopausal patients who were referred to the Medical Centre for an osteoporosis screening appointment by their general practitioner. All patients were interviewed (with a questionnaire containing questions on fracture risk factors and highest height), had their anthropometric measures taken (current height and weight) as well as TBS analysis following their DXA (dual-energy X-ray absorptiometry) scan and handgrip measure.ResultsSixty patients from the study group had a history of fractures (with a total of 92 fractures), of whom 39 women (76 fractures) were identified as those with a low-energy fracture. Fragility fractures were more likely to be reported in older patients (Me 71 vs. 68 years, p < 0.05). Differences observed between TBS, handgrip and BMD in reference to fragility fractures were not statistically significant. Analysis showed significant correlations between BMD (neck and L1–L4) and TBS fracture risk categories. Falls reported in the last 5 years and height loss were factors which correlated with fragility fractures (p < 0.05).ConclusionsRisk of fragility fractures increases with age. Bone mineral density is insufficient as a fracture risk assessment tool. Information on falls and height loss may provide additional data on fracture risk assessment.     

Real-world care for individuals aged over fifty with fractures in France: Evidence for a wide care gap–The EPIFRACT Study

ObjectivesTo describe the care trajectories of adults aged ≥ 50 years with fragility fractures in France.MethodsA postal questionnaire was sent to 15,000 individuals aged ≥ 50 years extracted from a representative panel of the French population (METASKOPE) in April-May 2018. Respondents experiencing a single fragility fracture in the previous three years constituted the study population. Information was collected regarding diagnosis, hospitalisations, physician visits and treatment related to the fractures.Results13,914 participants returned a questionnaire (92.8%), of whom 436 reported a single fragility fracture. Their mean age was 68.7 ± 10.3 years. 11.9% of this sample had undergone bone densitometry (DXA) prior to the fracture and 11.9% had received a diagnostic of osteoporosis. Following the fracture, a further 17.4% underwent DXA and 8.5% were diagnosed with osteoporosis. 74.3% of fractures were initially managed in an emergency department and 29.6% led to immediate hospitalisation. Prior to fracture, 3.4% received a specific anti-osteoporotic treatment, 10.1% vitamin D and 6.4% calcium supplementation. After the fracture, these figures rose to 10.8%, 26.8% and 19.0% respectively. 86.2% participants made at least one follow-up visit to a physician.ConclusionsThe rate of DXA screening following fragility fractures in subjects over fifty is very low. Most patients with fragility fractures did not receive a diagnosis of osteoporosis. The proportion of patients treated with a specific anti-osteoporotic treatment after a fracture is low even though around half consulted their general practitioner after the fracture. Practice guidelines are thus not being adhered to in everyday clinical practice in France.     

Women with previous stress fractures show reduced bone material strength

Background and purpose — Bone fragility is determined by bone mass, bone architecture, and the material properties of bone. Microindentation has been introduced as a measurement method that reflects bone material properties. The pathogenesis of underlying stress fractures, in particular the role of impaired bone material properties, is still poorly understood. Based on the hypothesis that impaired bone material strength might play a role in the development of stress fractures, we used microindentation in patients with stress fractures and in controls.

Patients and methods — We measured bone material strength index (BMSi) by microindentation in 30 women with previous stress fractures and in 30 normal controls. Bone mineral density by DXA and levels of the bone markers C-terminal cross-linking telopeptide of type-1 collagen (CTX) and N-terminal propeptide of type-1 procollagen (P1NP) were also determined.

Results — Mean BMSi in stress fracture patients was significantly lower than in the controls (SD 72 (8.7) vs. 77 (7.2); p = 0.02). The fracture subjects also had a significantly lower mean bone mineral density (BMD) than the controls (0.9 (0.02) vs. 1.0 (0.06); p = 0.03). Bone turnover—as reflected in serum levels of the bone marker CTX—was similar in both groups, while P1NP levels were significantly higher in the women with stress fractures (55?μg/L vs. 42?μg/L; p = 0.03). There was no correlation between BMSi and BMD or bone turnover.

Interpretation — BMSi was inferior in patients with previous stress fracture, but was unrelated to BMD and bone turnover. The lower values of BMSi in patients with previous stress fracture combined with a lower BMD may contribute to the increased propensity to develop stress fractures in these patients.     

A clinical calculator for predicting intraoperative blood loss and transfusion risk in spine tumor patients

BACKGROUND CONTEXTSurgery for vertebral column tumors is commonly associated with intraoperative blood loss (IOBL) exceeding 2 liters and the need for transfusion of allogeneic blood products. Transfusion of allogeneic blood, while necessary, is not benign, and has been associated with increased rates of wound complication, venous thromboembolism, delirium, and death.PURPOSETo develop a prediction tool capable of predicting IOBL and risk of requiring allogeneic transfusion in patients undergoing surgery for vertebral column tumors.STUDY DESIGN/SETTINGRetrospective, single-center study.PATIENT SAMPLEConsecutive series of 274 patients undergoing 350 unique operations for primary or metastatic spinal column tumors over a 46-month period at a comprehensive cancer centerOUTCOME MEASURESIOBL (in mL), use of intraoperative blood products, and intraoperative blood products transfused.METHODSWe identified IOBL and transfusions, along with demographic data, preoperative laboratory data, and surgical procedures performed. Independent predictors of IOBL and transfusion risk were identified using multivariable regression.RESULTSMean age at surgery was 57.0±13.6 years, 53.1% were male, and 67.1% were treated for metastatic lesions. Independent predictors of IOBL included en bloc resection (p<.001), surgical invasiveness (β=25.43 per point; p<0.001), and preoperative albumin (β=?244.86 per g/dL; p=0.011). Predictors of transfusion risk included preoperative hematocrit (odds ratio [OR]=0.88 per %; 95% confidence interval [CI, 0.84, 0.93]; p<0.001), preoperative MCHgb (OR=0.88 per pg; 95% CI [0.78, 1.00]; p=0.048), preoperative red cell distribution width (OR=1.32 per %; 95% CI [1.13, 1.55]; p<0.001), en bloc resection (OR=3.17; 95%CI [1.33, 7.54]; p=0.009), and surgical invasiveness (OR=1.08 per point; [1.06; 1.11]; p<0.001). The transfusion model showed a good fit of the data with an optimism-corrected area under the curve of 0.819. A freely available, web-based calculator was developed for the transfusion risk model (https://jhuspine3.shinyapps.io/TRUST/).CONCLUSIONSHere we present the first clinical calculator for intraoperative blood loss and transfusion risk in patients being treated for primary or metastatic vertebral column tumors. Surgical invasiveness and preoperative microcytic anemia most strongly predict transfusion risk. The resultant calculators may prove clinically useful for surgeons counseling patients about their individual risk of requiring allogeneic transfusion.     

Biopsychosocial sequelae of chronically painful injuries sustained in motor vehicle accidents contributing to non-recovery: A retrospective cohort study

BackgroundClaimants with chronically painful injuries sustained in motor vehicle accidents (MVAs) undergo assessment and management influenced by insurance and medico-legal processes defined by a biomedical paradigm which is discordant with best evidence. We aim to demonstrate the impact of biopsychosocial factors on post-MVA sequelae which contribute to non-recovery.MethodsThis was a retrospective cohort study of medico-legal documents and reports on 300 consecutive claimants referred to a pain medicine physician over 7 years (2012-2018) for assessment of painful musculoskeletal injuries post-MVA. One hundred data items were extracted from the medico-legal documents and reports for each claimant and entered into an electronic database. Post-MVA sequelae were analysed using chi-square analysis (OR >2) for significant associations with demographic, pre-MVA and post-MVA variables. Factors with significant associations were entered into a logistic regression model to determine significant statistical predictors of post-MVA sequelae contributing to non-recovery.ResultsThe claimants were aged 17 to 80 years (mean age 42 years), and approximately half (53%, n=159) were female. The time from MVA to interview averaged 2.5 years. Widespread pain was present in 18% (n=54), and widespread somatosensory signs implying central sensitisation (OR=9.85, p<.001) was the most significant multivariate association. Long-term opiate use post-MVA (32%) was predicted by pre-MVA sleep disturbance (OR=5.08, p=.001), post-MVA major depressive disorder (MDD) (OR=3.02, p=.003) and long-term unemployment (OR=2.22. p=.007). Approximately half (47%, n=142) required post-MVA support from a psychologist or psychiatrist. Post-traumatic stress disorder (PTSD) was diagnosed by a psychiatrist or psychologist in 20% (n=59), yet early identification of risk of PTSD was rare. Pre-MVA, 89.4% (n=268) were studying or employed. Permanent unemployability post-MVA occurred in 35% (n=104) and was predicted by MDD (OR=3.59, p=.001) and antidepressant use (OR=2.17, p=.005). Major social change post-MVA (70%) was predicted by older age (OR=.966, p=.003), depressive symptoms (OR=3.71, p<.001) and opiate use (OR=2.00, p=.039).ConclusionsBiomedical factors, including older age, impaired sleep and indicators of widespread central sensitisation, and psychological factors, including stress, anxiety and depression, were the most prominent multivariate associations as statistical predictors of major adverse sequelae contributing to non-recovery for claimants with chronic pain post-MVA.     

Risk stratification of patients undergoing outpatient lumbar decompression surgery

BACKGROUND CONTEXTReimbursement has slowly transitioned from a fee-for-service model to a bundled payment model after introduction of the United States Centers for Medicare and Medicaid Services bundled payment program. To minimize healthcare costs, some surgeons are trying to minimize healthcare expenditures by transitioning appropriately selected lumbar decompression patients to outpatient procedure centers.PURPOSETo prepare a risk stratification calculator based on machine learning algorithms to improve surgeon's preoperative predictive capability of determining whether a patient undergoing lumbar decompression will meet inpatient vs. outpatient criteria. Inpatient criteria was defined as any overnight hospital stay.STUDY DESIGN/SETTINGRetrospective single-institution cohort.PATIENT SAMPLEA total of 1656 patients undergoing primary lumbar decompression.OUTCOME MEASURESPostoperative outcomes analyzed for inclusion into the risk calculator included length of stay.METHODSPatients were split 80-20 into a training model and a predictive model. This resulted in 1,325 patients in the training model and 331 into the predictive model. A logistic regression analysis ensured proper variable inclusion into the model. C-statistics were used to understand model effectiveness. An odds ratio and nomogram were created once the optimal model was identified.RESULTSA total of 1,656 patients were included in our cohort with 1,078 dischared on day of surgery and 578 patients spending ≥ 1 midnight in the hospital. Our model determined older patients (OR=1.06, p<.001) with a higher BMI (OR=1.04, p<0.001), higher back pain (OR=1.06, p=.019), increasing American Society of Anesthesiologists (ASA) score (OR=1.39, p=.012), and patients with more levels decompressed (OR=3.66, p<0.001) all had increased risks of staying overnight. Patients who were female (OR=0.59, p=.009) and those with private insurance (OR=0.64, p=.023) were less likely to be admitted overnight. Further, weighted scores based on training data were then created and patients with a cumulative score over 118 points had a 82.9% likelihood of overnight. Analysis of the 331 patients in the test data demonstrated using a cut-off of 118 points accurately predicted 64.8% of patients meeting inpatient criteria compared to 23.0% meeting outpatient criteria (p<0.001). Area under the curve analysis showed a score greater than 118 predicted admission 81.4% of the time. The algorithm was incorporated into an open access digital application available here: https://rothmanstatisticscalculators.shinyapps.io/Inpatient_Calculator/?_ga=2.171493472.1789252330.1671633274-469992803.1671633274CONCLUSIONSUtilizing machine-learning algorithms we created a highly reliable predictive calculator to determine if patients undergoing outpatient lumbar decompression would require admission. Patients who were younger, had lower BMI, lower preoperative back pain, lower ASA score, less levels decompressed, private insurance, lived with someone at home, and with minimal comorbidities were ideal candidates for outpatient surgery.     

Fracture Risk Assessment and Drug Holiday in a Real-Life Setting

Purpose: Describe fracture risk assessment practices among physicians treating osteoporosis in a real-life setting. Methods:This is a retrospective cohort study in a tertiary academic center. Inclusion criteria involved adults (aged ≥18 years) who received minimum adequate therapy (bisphosphates, raloxifene, or denosumab ≥ 3 years or teriparatide ≥ 18 months). Of 1,814 charts randomly selected and reviewed, 274 patients met the inclusion criteria.Risk stratification tools included fragility fractures, Dual-energy X-ray Absorptiometry (DXA), and fracture risk assessment using the FRAX tool. Fracture risk assessment was performed before therapy initiation (N= 274) and at the time of institution of the drug holiday (N=119). High-risk patients were defined as the presence of a fragility fracture, T-score ≤-2.5, or a high-risk score by FRAX calculation. FRAX scores were independently calculated by the research team for comparison and assessment purposes. Results: Before initiation of therapy (N=274) versus upon starting a drug holiday (DH; N=119), 29.9% versus 3.4% had a history of fragility fractures (P<0.001), 58.8% versus 67.2% had a DXA scan performed (P>0.05), 10.5% versus 10.9% of physicians calculated a FRAX score (P>0.05), and 71.5% versus 66.4% were considered at high risk and eligible for therapy. A DXA scan was performed after DH in 40.2% of these patients and at least once in 95.3% of the entire cohort. Conclusion: The reporting of FRAX score in DXA scan reports may significantly increase its utilization in fracture risk assessment. We recommend comprehensive fracture risk assessment utilizing history of prevalent osteoporosis fractures, DXA assessment, and FRAX scoring.     

High viscosity bone cement vertebroplasty versus low viscosity bone cement vertebroplasty in the treatment of mid-high thoracic vertebral compression fractures

BACKGROUND CONTEXTAs science and technology have advanced, novel bone cements with numerous formulated ingredients have greatly evolved and been commercialized for vertebroplasty. Recently, viscosity has been a focus to achieve better clinical outcomes and fewer complications. Meanwhile, the experience in the treatment of mid (T7–9) to high (T4–6) thoracic vertebral compression fractures is limited.PURPOSEThe objective of this study was to identify the different outcomes between high-viscosity bone cement (HVBC) and low-viscosity bone cement (LVBC) used to repair mid (T7–9)- and high (T4–6)- thoracic vertebral compression fractures.STUDY DESIGN/SETTINGThis study was a single-center, retrospective cohort studyPATIENT SAMPLEA consecutive series of 107 patients with a total of 144 vertebrae was included.OUTCOME MEASURESThe anterior vertebral height (AVH), middle vertebral height (MVH), posterior vertebral height (PVH), local kyphotic angle (KA), Cobb angle (CA), and other associated parameters were evaluated radiologically at several time points—preoperative, surgery day 0, postoperative day 1, and 6-month follow-up. Pain evaluation was assessed by using a visual analog scale (VAS) before and 6 months after the procedure.METHODSThe patients were divided into two groups according to the viscosity of the bone cement used, and plain film and magnetic resonance imaging (MRI) of the vertebrae were used to calculate parameters. The patient characteristics; bone cement brand; changes in AVH, MVH, PVH, KA, CA, and VAS; and complications of each patient were recorded and then analyzed.RESULTSBoth groups showed increased vertebral body height, corrected KA, and CA after vertebroplasty. There were no significant differences between the HVBC and LVBC groups (ΔAVH: 2.19±2.60 vs. 2.48±3.09, p=.555; ΔMVH: 1.25±3.15 vs. 1.89±2.58, p=.192; ΔKA: -5.46±4.58 vs -5.37±4.47, p=.908; and ΔCA: -4.22±4.23 vs. -4.56±5.17, p=.679). There were significant preoperative to postoperative and preoperative to follow-up changes in AVH (HVBC, p=.012 and .046, respectively; LVBC, p=.001 and .015, respectively); a significant preoperative to postoperative change in MVH (HVBC, p=.045; LVBC, p=.001); and significant preoperative to postoperative and preoperative to follow-up changes in KA and CA (KA: HVBC, p=0.000 and .003, respectively; LVBC, p=.000 and .000, respectively; CA: HVBC, p=.017 and .047, respectively; LVBC, p=.006 and .034, respectively). The volume of cement injected was significantly higher with HVBC (3.66±1.36 vs. 3.11±1.53, p=.024), and the use of HVBC was associated fewer cases with cement leakage (26 vs. 45, p=.002). Furthermore, there was no difference between the groups in the incidence of adjacent fracture. Both groups showed an improved VAS score at follow-up, with statistically greater improvement in the HVBC group (2.40±1.53 vs. 3.07±1.69, p=.014). Moreover, significantly fewer patients with a VAS score ≥ 3 were found in the HVBC group (22 vs. 39, p=.004)CONCLUSIONSHVBC and LVBC are safe and effective to treat mid-to-high level thoracic vertebral compression fractures. Compared with LVBC, HVBC shows less cement leakage, a greater injection volume, and better postoperative pain relief.