Establishment and Validation of a Nomogram for the Risk of New Vertebral Compression Fractures After Percutaneous Vertebroplasty in Patients With Osteoporotic Vertebral Compression Fractures: A Retrospective Study

Integration of Spinal Musculoskeletal System Parameters for Predicting OVCF in the Elderly: A Comprehensive Predictive Model

Study DesignSystematic literature review.ObjectivesTo develop a predictive model for osteoporotic vertebral compression fractures (OVCF) in the elderly, utilizing current tools that are sensitive to bone and paraspinal muscle changes.MethodsA retrospective analysis of data from 260 patients from October 2020 to December 2022, to form the Model population. This group was split into Training and Testing sets. The Training set aided in creating a nomogram through binary logistic regression. From January 2023 to January 2024, we prospectively collected data from 106 patients to constitute the Validation population. The model's performance was evaluated using concordance index (C-index), calibration curves, and decision curve analysis (DCA) for both internal and external validation.ResultsThe study included 366 patients. The Training and Testing sets were used for nomogram construction and internal validation, while the prospectively collected data was for external validation. Binary logistic regression identified nine independent OVCF risk factors: age, bone mineral density (BMD), quantitative computed tomography (QCT), vertebral bone quality (VBQ), relative functional cross-sectional area of psoas muscles (rFCSAPS), gross and functional muscle fat infiltration of multifidus and psoas muscles (GMFIES+MF and FMFIES+MF), FMFIPS, and mean muscle ratio. The nomogram showed an area under the curve (AUC) of 0.91 for the C-index, with internal and external validation AUCs of 0.90 and 0.92. Calibration curves and DCA indicated a good model fit.ConclusionsThis study identified nine factors as independent predictors of OVCF in the elderly. A nomogram including these factors was developed, proving effective for OVCF prediction.

Vertebral CT Hounsfield units in postmenopausal women with osteoporotic vertebral compression fracture: identification and validation of reference intervals

PURPOSE

Based on the population of postmenopausal women with osteoporotic vertebral compression fractures (OVCFs), this study aimed to identify the optimal and alternative levels of vertebral CT Hounsfield units (HU) for osteoporosis and osteoporosis-related complication assessment, establish age-specific reference intervals (RIs) of HU values, and validate its quantitative predictive value for new vertebral fractures (NVFs) after percutaneous kyphoplasty (PKP).

METHODS

Consecutive postmenopausal women diagnosed with OVCFs at our department between January 2016 and August 2024 were retrospectively reviewed. The vertebral HU of T12-L2 was measured on CT images by two independent spine surgeons twice, with a 2-week interval. The segmental average HU was assessed in terms of the representativeness of overall osteoporotic status, reproducibility, and association with clinical outcomes to identify the optimal and alternative levels. Age-specific RIs were built using the indirect Hoffmann method. The associations between HU and NVFs were assessed by correlation, receiver operator characteristic (ROC) curve, and multivariate analyses.

RESULTS

A total of 922 patients were enrolled in the optimal level identification and RI establishment study. Intraclass correlation coefficient (ICC) between segmental and average HU values was the highest at L1 (ICC, 0.970), followed by T12 (ICC, 0.955) and L2 (ICC, 0.955) in the whole population. The age-specific RIs determined in postmenopausal women with primary OVCFs were 39.22-170.92 HU (56-65 years), 21.23-132.48 HU (66-75 years), and 11.15-108.85 HU (> 75 years) at T12; 37.25-156.46 HU (56-65 years), 17.83-123.68 HU (66-75 years), and 10.71-103.59 HU (> 75 years) at L1; and 30.88-148.28 HU (56-65 years), 9.61-121.00 HU (66-75 years), and - 1.67 to 99.65 HU (> 75 years) at L2. Significant weak negative correlations were found between NVFs and average/segmental HU value (Spearman r, - 0.146 to - 0.245, P < 0.05), and risks of nonadjacent NVFs, fracture cascade, and overall NVFs after PKP increased in the individuals with decreases in HU (particularly at L1).

CONCLUSION

This study identified the optimal and alternative levels of CT HU value in postmenopausal women with OVCFs and established its corresponding age-specific RIs. Furthermore, we validated that low HU value posed high risks of NVFs after PKP and quantitatively clarified the dynamic trend of their association. This study may provide inspiration and a novel methodological approach for further research on osteoporotic diseases.

The lowest HU value on transverse planes: a predictive factor for cranial adjacent vertebral fracture risk after percutaneous vertebroplasty

Background

Osteoporosis is the major risk factor for adjacent vertebral fracture (AVF). T-Score (DXAsp) cannot eliminate the confounding effect caused by pathological osteogenesis. Hounsfield unit (HU) values are credible predictors of bone density but cannot elucidate its regional differences. Since fracture occurs in the section with the lowest strength, HU values should be reliable predictors for AVF, and the predictive performance of the lowest HU in transverse planes should be better than those of other HU parameters. This study was designed to validate this hypothesis and to introduce an innovative parameter that can more accurately assess the incidence of AVF.

Methods

We conducted a retrospective review of prospectively collected imaging data from 103 patients diagnosed with a single segmental osteoporotic vertebral compression fracture (OVCF) who underwent percutaneous vertebroplasty (PVP) between July 2016 and August 2019. The average follow-up period for these patients was 24.1 months. T-Score (DXAsp) and HU values had been used to measure patients' bone density. HU was measured separately in the central transverse plane, the average values of three and four planes, and the lowest HU in transverse planes. Regression analyses identified independent risk factors for the cranial segmental AVF. We also performed receiver operating characteristic (ROC) curve analyses to assess the significant differences in predictive performances for different indicators.

Results

The overall incidence rate of AVF was found to be 26.21% (27 out of 103 cases). The HU values were significantly different; however, the T-Score (DXAsp) exhibited an insignificantly lower value in patients with cranial AVF following PVP. The area under the curve (AUC) values for four planes and three planes-average HU value, central transverse plane HU value, lowest HU value, and T-Score (DXAsp)-were recorded as 0.703, 0.705, 0.703, 0.765, and 0.57 respectively. Notably, the AUC of the lowest HU in transverse planes was significantly superior to that of the T-Score (DXAsp) and other HU measurement methods, with the exception of the central transverse plane HU value (P=0.118).

Conclusions

Compared to T-Score (DXAsp) and other traditional methods of HU measurement, the lowest HU value obtained from transverse planes demonstrates a superior ability to predict the incidence of AVF. Therefore, measuring this parameter is recommended for a more accurate assessment of AVF risk.

Forearm bone mineral density as a predictor of adjacent vertebral refracture after percutaneous kyphoplasty in patients with osteoporotic vertebral compression fracture: a retrospective analysis

BACKGROUND

The incidence of adjacent vertebral body re-fracture after percutaneous kyphoplasty (PKP) is associated with a number of variables, of which decreased bone mineral density is one of the major risk factors. Forearm bone mineral density (BMD) measurements are gaining attention because of their convenience and validity, but there is a lack of systematic research on the specific relationship between forearm BMD and the risk of adjacent vertebral re-fracture after PKP.

PURPOSE

To investigate the correlation between forearm BMD and the risk of adjacent vertebral re-fracture after PKP in osteoporotic vertebral compression fractures (OVCF) patients.

METHODS

Retrospective evaluation of 198 OVCF patients receiving PKP was conducted in this study. The patients were divided into two groups: the no-fracture group and the re-fracture group, according to whether or not they had undergone vertebral re-fracture. Obtain basic information about the patient's age, sex, body mass index, bone cement leakage, smoking history, diabetes history, and surgical segmentation. Using computed tomography, the mean Hounsfield unit (HU) values for the BMD of the L1 lumbar spine were determined. For the dual-energy X-ray BMD test, the distal one-third lengths of the patient's nondominant forearm's radius and ulna were chosen. Receiver operating characteristic curves were utilized to evaluate the predictive value of forearm BMD versus lumbar CT values for vertebral re-fracture, and univariate and multivariate logistic regression analyses were employed to identify characteristics related with vertebral re-fracture following PKP.

RESULTS

Re-fracture rate after PKP was 17.2% at a minimum 12-month follow-up. Significant differences were seen between the refracture and non-fracture groups in terms of hypertension, Cobb angle correction, vertebral height recovery rate, intradiscal cement leakage, forearm bone density, and vertebral HU values. In multifactorial logistic regression analysis, forearm bone density (OR 0.821; 95% CI 0.728-0.937, p = 0.008) and HU values (OR 0.815; 95% CI 0.733-0.906, p = 0.005) were independent risk factors for vertebral re-fracture. The area under the curve (AUC) for forearm BMD values and HU values predicting adjacent vertebral re-fracture were 0.956 and 0.967, respectively.

CONCLUSIONS

Forearm BMD is an independent risk factor for re-fracture of adjacent vertebrae after PKP. In addition, forearm BMD, as a valid indicator of postoperative re-fracture after PKP in patients with OVCF, and the HU value of lumbar spine CT were both powerful tools for predicting re-fracture.

Prediction of new vertebral compression fracture within 3 years after percutaneous vertebroplasty for osteoporotic vertebral compression fracture: Establishment and validation of a nomogram prediction model

New vertebral compression fractures (NVCF) are common in patients with osteoporotic vertebral compression fractures (OVCF) who have undergone percutaneous vertebroplasty (PVP). We sought to develop a nomogram prediction model for better identification and prevention of NVCF within 3 years after PVP in patients with OVCF. The demographic, clinical, and imaging data of patients who underwent PVP for OVCF between January 2010 and December 2019 were reviewed. Multivariate logistic regression analysis was used to screen for risk factors for NVCF within 3 years after PVP. A nomogram prediction model was then developed and validated to visually predict NVCF. The samples in the model were randomly divided into training and validation sets at a ratio of 7:3. Twenty-seven percent of patients experienced NVCF in other segments within 3 years after PVP. Older age, lower bone mineral density (BMD), smoking, lack of anti-osteoporosis therapy, and postoperative trauma were risk factors for NVCF. The area under the receiver operating characteristic curve suggested good discrimination of this model: training set (0.781, 95% confidence interval: 0.731-0.831) and validation set (0.786, 95% confidence interval: 0.708-0.863). The calibration curve suggested good prediction accuracy between the actual and predicted probabilities in the training and validation sets. The DCA results suggested that, when the probability thresholds were 0.0452-08394 and 0.0336-0.7262 in the training and validation set, respectively, patients can benefit from using this model to predict NVCF within 3 years after PVP. In conclusion, this nomogram prediction model that included five risk factors (older age, lower BMD, smoking, postoperative minor trauma, and lack of anti-osteoporosis treatment can effectively predict NVCF within 3 years after PVP. Postoperative smoking cessation, standard anti-osteoporosis treatment, and reduction in incidental minor trauma are necessary and effective means of reducing the incidence of NVCF.

The cranial vertebral body suffers a higher risk of adjacent vertebral fracture due to the poor biomechanical environment in patients with percutaneous vertebralplasty

BACKGROUND CONTEXT

Adjacent vertebral fracture (AVF), a frequent complication of PVP, is influenced by factors such as osteoporosis progression, increased intervertebral cement leakage (ICL), and biomechanical deterioration. Notably, the risk of AVF is notably elevated in the cranial vertebral body compared with the caudal counterpart. Despite this knowledge, the underlying pathological mechanism remains elusive.

PURPOSE

This study delves into the role of biomechanical deterioration as a pivotal factor in the heightened risk of AVF in the cranial vertebral body following PVP. By isolating this variable, we aim to unravel its prominence relative to other potential risk factors.

STUDY DESIGN

A retrospective study and corresponding numerical mechanical simulations.

PATIENT SAMPLE

Clinical data from 101 patients treated by PVP were reviewed in this study.

OUTCOME MEASURES

Clinical assessments involved measuring Hounsfield unit (HU) values of adjacent vertebral bodies as a representation of patients' bone mineral density (BMD). Additionally, the rates of ICL were compared among these patients. Numerical simulations were conducted to compute stress values in the cranial and caudal vertebral bodies under various body positions.

METHODS

In a retrospective analysis of PVP patients spanning July 2016 to August 2019, we scrutinized the HU values of adjacent vertebral bodies to discern disparities in BMD between cranial and caudal regions. Additionally, we compared ICL rates on both cranial and caudal sides. To augment our investigation, well-validated numerical models simulated the PVP procedure, enabling the computation of maximum stress values in cranial and caudal vertebral bodies across varying body positions.

RESULTS

The incidence rate of cranial AVF was significantly higher than the caudal side. No notable distinctions in HU values or ICL rates were observed between the cranial and caudal sides. The incidence of AVF showed no significant elevation in patients with ICL in either region. However, numerical simulations unveiled heightened stress values in the cranial vertebral body.

CONCLUSIONS

In patients postPVP, the cranial vertebral body faces a heightened risk of AVF, primarily attributed to biomechanical deterioration rather than lower BMD or an elevated ICL rate.

Effect of osteosarcopenia on the development of a second compression fracture and mortality in elderly patients after vertebroplasty

OBJECTIVE

This study aimed to investigate the effect of osteosarcopenia on second fracture development and mortality in patients aged above 60 years undergoing vertebroplasty because of osteoporotic vertebral compression fracture (OVCF).

METHODS

A retrospective evaluation was conducted on 104 patients treated by vertebroplasty because of OVF between 2016 and 2021. The L3 vertebra Hounsfield unit values and the psoas muscle index (PMI) values measured at the L3 vertebra level were obtained from the patients' medical data and computed tomography images. Using these measurements, the patients were divided into 3 groups: only osteoporosis (OO group), only sarcopenia (OS group), and osteosarcopenia (OSP group). Differences between the groups were evaluated regarding second OVCF development and mortality.

RESULTS

The study included 104 patients, comprising 30 males and 74 females aged 60-92 years. The OS group included 10 patients, the OO group included 54 patients, and the OSP group consisted of 40 patients. A single vertebral fracture occurred in 72 patients, and 2 vertebral fractures occurred in 32 patients. The chi-square test, Mann-Whitney U-test, Kruskal-Wallis test, and Kaplan-Meier survival analysis results showed no statistically significant difference between the 3 groups for the risk of second vertebral fracture. Sarcopenia, either alone or in combination with osteoporosis, was seen to have a negative effect on the survival of patients who underwent vertebro- plasty following a vertebral fracture.

CONCLUSION

This study has shown that osteosarcopenia did not increase the risk of developing a second vertebral fracture, but it increased mortality 2.8-fold for those who underwent vertebroplasty after vertebral fracture.

LEVEL OF EVIDENCE

Level III, Prognostic study.

Red flags to screen for vertebral fracture in people presenting with low back pain

BACKGROUND

Low back pain is a common presentation across different healthcare settings. Clinicians need to confidently be able to screen and identify people presenting with low back pain with a high suspicion of serious or specific pathology (e.g. vertebral fracture). Patients identified with an increased likelihood of having a serious pathology will likely require additional investigations and specific treatment. Guidelines recommend a thorough history and clinical assessment to screen for serious pathology as a cause of low back pain. However, the diagnostic accuracy of recommended red flags (e.g. older age, trauma, corticosteroid use) remains unclear, particularly those used to screen for vertebral fracture.

OBJECTIVES

To assess the diagnostic accuracy of red flags used to screen for vertebral fracture in people presenting with low back pain. Where possible, we reported results of red flags separately for different types of vertebral fracture (i.e. acute osteoporotic vertebral compression fracture, vertebral traumatic fracture, vertebral stress fracture, unspecified vertebral fracture).

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 26 July 2022.

SELECTION CRITERIA

We considered primary diagnostic studies if they compared results of history taking or physical examination (or both) findings (index test) with a reference standard test (e.g. X-ray, magnetic resonance imaging (MRI), computed tomography (CT), single-photon emission computerised tomography (SPECT)) for the identification of vertebral fracture in people presenting with low back pain. We included index tests that were presented individually or as part of a combination of tests.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data for diagnostic two-by-two tables from the publications or reconstructed them using information from relevant parameters to calculate sensitivity, specificity, and positive (+LR) and negative (-LR) likelihood ratios with 95% confidence intervals (CIs). We extracted aspects of study design, characteristics of the population, index test, reference standard, and type of vertebral fracture. Meta-analysis was not possible due to heterogeneity of studies and index tests, therefore the analysis was descriptive. We calculated sensitivity, specificity, and LRs for each test and used these as an indication of clinical usefulness. Two review authors independently conducted risk of bias and applicability assessment using the QUADAS-2 tool.

MAIN RESULTS

This review is an update of a previous Cochrane Review of red flags to screen for vertebral fracture in people with low back pain. We included 14 studies in this review, six based in primary care, five in secondary care, and three in tertiary care. Four studies reported on 'osteoporotic vertebral fractures', two studies reported on 'vertebral compression fracture', one study reported on 'osteoporotic and traumatic vertebral fracture', two studies reported on 'vertebral stress fracture', and five studies reported on 'unspecified vertebral fracture'. Risk of bias was only rated as low in one study for the domains reference standard and flow and timing. The domain patient selection had three studies and the domain index test had six studies rated at low risk of bias. Meta-analysis was not possible due to heterogeneity of the data. Results from single studies suggest only a small number of the red flags investigated may be informative. In the primary healthcare setting, results from single studies suggest 'trauma' demonstrated informative +LRs (range: 1.93 to 12.85) for 'unspecified vertebral fracture' and 'osteoporotic vertebral fracture' (+LR: 6.42, 95% CI 2.94 to 14.02). Results from single studies suggest 'older age' demonstrated informative +LRs for studies in primary care for 'unspecified vertebral fracture' (older age greater than 70 years: 11.19, 95% CI 5.33 to 23.51). Results from single studies suggest 'corticosteroid use' may be an informative red flag in primary care for 'unspecified vertebral fracture' (+LR range: 3.97, 95% CI 0.20 to 79.15 to 48.50, 95% CI 11.48 to 204.98) and 'osteoporotic vertebral fracture' (+LR: 2.46, 95% CI 1.13 to 5.34); however, diagnostic values varied and CIs were imprecise. Results from a single study suggest red flags as part of a combination of index tests such as 'older age and female gender' in primary care demonstrated informative +LRs for 'unspecified vertebral fracture' (16.17, 95% CI 4.47 to 58.43). In the secondary healthcare setting, results from a single study suggest 'trauma' demonstrated informative +LRs for 'unspecified vertebral fracture' (+LR: 2.18, 95% CI 1.86 to 2.54) and 'older age' demonstrated informative +LRs for 'osteoporotic vertebral fracture' (older age greater than 75 years: 2.51, 95% CI 1.48 to 4.27). Results from a single study suggest red flags as part of a combination of index tests such as 'older age and trauma' in secondary care demonstrated informative +LRs for 'unspecified vertebral fracture' (+LR: 4.35, 95% CI 2.92 to 6.48). Results from a single study suggest when '4 of 5 tests' were positive in secondary care, they demonstrated informative +LRs for 'osteoporotic vertebral fracture' (+LR: 9.62, 95% CI 5.88 to 15.73). In the tertiary care setting, results from a single study suggest 'presence of contusion/abrasion' was informative for 'vertebral compression fracture' (+LR: 31.09, 95% CI 18.25 to 52.96).

AUTHORS' CONCLUSIONS

The available evidence suggests that only a few red flags are potentially useful in guiding clinical decisions to further investigate people suspected to have a vertebral fracture. Most red flags were not useful as screening tools to identify vertebral fracture in people with low back pain. In primary care, 'older age' was informative for 'unspecified vertebral fracture', and 'trauma' and 'corticosteroid use' were both informative for 'unspecified vertebral fracture' and 'osteoporotic vertebral fracture'. In secondary care, 'older age' was informative for 'osteoporotic vertebral fracture' and 'trauma' was informative for 'unspecified vertebral fracture'. In tertiary care, 'presence of contusion/abrasion' was informative for 'vertebral compression fracture'. Combinations of red flags were also informative and may be more useful than individual tests alone. Unfortunately, the challenge to provide clear guidance on which red flags should be used routinely in clinical practice remains. Further research with primary studies is needed to improve and consolidate our current recommendations for screening for vertebral fractures to guide clinical care.

Risk factors of new vertebral compression fracture after percutaneous vertebroplasty or percutaneous kyphoplasty

BACKGROUND

New vertebral compression fracture (VCF) may occur in patients who underwent percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fracture (OVCF). However, the risk factors of new VCF remain controversial. The research aimed to analyze the risk factors of new VCF after PVP or PKP.

METHODS

From August 2019 to March 2021, we retrospectively analyzed the patients who underwent PVP or PKP for OVCF at our institution. Age, gender, body mass index (BMI), smoking, drinking, hypertension, diabetes, fracture location, surgical method, Hounsfield unit (HU) value, preoperative degree of anterior vertebral compression (DAVC), bisphosphonates, bone cement volume, bone cement leakage, and cement distribution were collected. The risk factors were obtained by univariate and multivariate analysis of the data.

RESULTS

A total of 247 patients were included in the study. There were 23 patients (9.3%) with new VCF after PVP or PKP. Univariate analysis showed that age (p < 0.001), BMI (p = 0.002), fracture location (p = 0.030), and a low HU value (p < 0.001) were significantly associated with new VCF after PVP or PKP. A low HU value was an independent risk factor for new VCF after PVP or PKP obtained by multivariate regression analysis (OR = 0.963; 95% CI, 0.943-0.984, p = 0.001).

CONCLUSIONS

In this study, a low HU value was an independent risk factor of new VCF after PVP or PKP.