Difference of clinical course between cases with bone union and those with delayed union following osteoporotic vertebral fractures

Comparison of osteoanabolic agents (teriparatide and romosozumab) with bisphosphonates in prevention of subsequent vertebral fractures in patients treated for osteoporotic vertebral fracture for 12 months: An observational cohort study

Introduction

Domino osteoporotic vertebral fracture (OVF) is as a subsequent fracture that develops within 3 months before the initial OVF heals. There is limited evidence regarding the efficacy of osteoanabolic agents on its treatment. This study evaluated the effects of bisphosphonates and anabolic agents teriparatide and romosozumab on subsequent domino OVF.

Methods

This was post hoc analysis of a prospective, multicenter, observational study conducted across 8 hospitals, enrolling 144 patients with conservatively treated OVF, grouped into patients receiving bisphosphonate (BP, n = 55), teriparatide (TPTD, n = 62), and romosozumab (Romo, n = 27). The primary outcome was the incidence of subsequent OVF at 3 and 12 months, whereas the secondary outcomes included the incidence of pseudoarthrosis and progression of vertebral collapse (VC). Pseudoarthrosis was classified as stable or unstable based on vertebral instability.

Results

The use of osteoanabolic agents did not reduce the incidence of subsequent OVF at 3 and 12 months. There were no significant differences in the background data or type of conservative treatment among the three groups. However, the TPTD and Romo groups had significantly lower rates of unstable pseudarthrosis (p = 0.03). Additionally, there were no significant differences in VC progression between groups, but it tended to be higher in the BP group than the TPTD and Romo group (p = 0.07).

Conclusion

Osteoanabolic agents were beneficial in reducing unstable pseudoarthrosis, but were not more effective than bisphosphonates in the development of subsequent domino OVF. A more comprehensive approach to the treatment of osteoporosis is needed to prevent domino OVFs.

External validation of predictive models for new vertebral fractures following percutaneous vertebroplasty

OBJECTIVE

To investigate the external validation and scalability of four predictive models regarding new vertebral fractures following percutaneous vertebroplasty.

METHODS

Utilizing retrospective data acquired from two centers, compute the area under the curve (AUC), calibration curve, and Kaplan-Meier plot to assess the model's discrimination and calibration.

RESULTS

In the external validation of Zhong et al.'s 2015 predictive model for the probability of new fractures post-vertebroplasty, the AUC for re-fracture at 1, 2, and 3 years postoperatively was 0.570, 0.617, and 0.664, respectively. The AUC for Zhong et al.'s 2016 predictive model for the probability of new fractures in neighboring vertebrae was 0.738. Kaplan-Meier plot results for both models indicated a significantly lower incidence of re-fracture in low-risk patients compared to high-risk patients. Li et al.'s 2021 model had an AUC of 0.518, and its calibration curve suggested an overestimation of the probability of new fractures. Li et al.'s 2022 model had an AUC of 0.556, and its calibration curve suggested an underestimation of the probability of new fractures.

CONCLUSION

The external validation of four models demonstrated that the predictive model proposed by Zhong et al. in 2016 exhibited superior external generalization capabilities.

Risk factors for nonunion of osteoporotic vertebral compression fracture: a case‒control study

BACKGROUND

Early assessment of the risk of nonunion in osteoporotic vertebral compression fracture (OVCF) is beneficial to early clinical decision making. However, a comprehensive understanding of the risk factors for OVCF nonunion is lacking.

METHODS

We conducted a case-control study to investigate risk factors for OVCF nonunion. Patients who underwent surgery for nonunited OVCFs between January 2011 and December 2021 were eligible for inclusion as cases. Patients with successful OVCF healing confirmed by MRI over the same period were identified as controls. Patient demographics, comorbidities, and fasting blood test data were extracted for analysis.

RESULTS

A total of 201 patients with nonunited OVCFs and 1044 controls were included to evaluate the risk factors for nonunited OVCFs. There were statistically significant differences in sex, age, number of patients with hypertension, number of patients on bed rest after OVCF and T-score of BMD between the two groups. Logistic regression showed that female patients had a higher risk of OVCF nonunion than male patients and that smoking, drinking, diabetes, and hypertension were risk factors for nonunion of OVCFs, while bed rest and spinal support were protective factors against nonunion of OVCFs. We also found that age, BMD, FBG, and β-CTX were positively correlated with nonunited OVCFs, and that HGB and 1,25-(OH)2VitD3 level were negatively correlated with nonunited OVCFs.

CONCLUSION

Smoking, drinking, diabetes and hypertension were risk factors for nonunion of OVCFs, while bed rest and spinal support were protective factors against nonunion of OVCFs. Age, BMD, FBG and β-CTX were positively correlated with nonunited OVCFs, while HGB and 1,25-(OH)2VitD3 level were negatively correlated with nonunited OVCFs. Based on the results of our study, we suggest that bed rest or spinal support for at least 3 consecutive weeks is necessary to reduce the risk of OVCFs nonunion.

Incidence, Risk Factors, and Outcomes of Symptomatic Bone Cement Displacement following Percutaneous Kyphoplasty for Osteoporotic Vertebral Compression Fracture: A Single Center Study

STUDY DESIGN

Retrospective.

BACKGROUND

Symptomatic bone cement displacement (BCD) is a rare complication following percutaneous kyphoplasty (PKP) interventions for osteoporotic vertebral compression fracture (OVCF). This study aimed to investigate the incidence and the outcomes of symptomatic BCD comprehensively and identify its risk factors.

METHODS

The clinical data of patients treated with PKP for OVCF between January 2012 and December 2020 were extracted. Patients who developed BCD following PKP during follow-up were divided into the symptomatic and asymptomatic groups. Patients who did not develop BCD were assigned to the control group. Univariate and multiple logistic regression analyses were used to compare the three clinical groups' features to assess the independent risk factors for the symptomatic and asymptomatic groups.

RESULTS

A total of 896 patients were enrolled. Twenty-one patients (2.3%) were identified as having symptomatic BCD following PKP for OVCF, and 35 (3.9%) developed asymptomatic BCD. Compared with the control group, the symptomatic and asymptomatic groups had a higher incidence of anterior leakage, intravertebral vacuum cleft (IVC) signs, and a lower cement distribution score. The symptomatic group had a lower relative cross-sectional area (rCSA) of the paraspinal muscle (PSM), higher PSM fatty degeneration, and higher kyphotic angle (at the last follow-up) than the asymptomatic and control groups. For outcomes, the symptomatic group had a higher VAS/ODI score and a higher incidence of new vertebral fractures compared with the asymptomatic and control groups. Anterior leakage (OR: 1.737, 95% CI: 1.215-3.300), the IVC sign (OR: 3.361, 95% CI: 1.605-13.036), the cement distribution score (OR: 0.476, 95% CI: 0.225-0.904), PSM rCSA (OR: 0.953, 95% CI: 0.917-0.992), and PSM fatty degeneration (OR: 1.061, 95% CI: 1.005-1.119) were identified as independent risk factors for the symptomatic group. Anterior leakage (OR: 1.839, 95% CI: 1.206-2.803), the IVC sign (OR: 2.936, 95% CI: 1.174-9.018), and cement distribution score (OR: 0.632, 95% CI: 0.295-0.858) were independent risk factors for the asymptomatic group.

CONCLUSION

The incidence of symptomatic BCD is 2.3% in patients treated with PKP. Anterior leakage, the IVC sign, and the distribution score were independent risk factors for BCD, and paraspinal muscle degeneration was a specific risk factor for symptomatic BCD. Symptomatic BCD can lead to poor outcomes.

Therapeutic Effects of Conservative Treatment with 2-Week Bed Rest for Osteoporotic Vertebral Fractures: A Prospective Cohort Study

UPDATE

This article was updated on October 19, 2022, because of previous errors, which were discovered after the preliminary version of the article was posted online. On page 1787, in the legend for Figure 2, the sentence that had read "The vertebral collapse rate (in %) was defined as 1 - (A/P) × 100, and vertebral instability (in %) was defined as the difference in vertebral collapse rate between the loaded and non-loaded images." now reads "The vertebral collapse rate (in %) was defined as (1 - [A/P]) × 100, and vertebral instability (in %) was defined as the difference in vertebral collapse rate between the loaded and non-loaded images." On page 1788, in the section entitled "Data Collection," the sentence that had read "The vertebral collapse rate (in %) was defined as 1 - (anterior vertebral wall height/posterior vertebral wall height) × 100, and vertebral instability (in %) was defined as the difference in vertebral collapse rate between the loaded and non-loaded images 9 ." now reads "The vertebral collapse rate (in %) was defined as (1 - [anterior vertebral wall height/posterior vertebral wall height]) × 100, and vertebral instability (in %) was defined as the difference in vertebral collapse rate between the loaded and non-loaded images 9 ." Finally, on page 1791, in Table IV, the footnote for the "Primary outcome" row that had read "N = 113 in the rest group and 99 in the no-rest group." now reads "N = 116 in the rest group and 108 in the no-rest group."

Relationship between number of radiological risk factors for delayed union after osteoporotic vertebral fracture and clinical outcomes

This study demonstrated that number of three specific radiological risk factors (MR T2WI confined high-intensity pattern and diffuse low-intensity pattern, thoracolumbar vertebrae involvement, middle column injury) added prognostic information for delayed union, kyphotic deformity, and prolonged pain.

PURPOSE

Delayed union after osteoporotic vertebral fracture (OVF) causes prolonged pain, QOL impairment, progression of collapse, kyphotic deformity, and neurologic impairment. Some specific radiological findings can be useful for predicting delayed union. We aimed to explore the prevalence and concomitance of various types of radiological risk factors for delayed union after osteoporotic vertebral fracture (OVF) and to assess the impact of risk factor number on clinical outcomes.

METHODS

A total of 508 patients with fresh OVF from 25 institutes were evaluated. All patients were treated conservatively without surgical interventions. At the 6-month follow-up, the patients were classified into bone union and delayed union groups based on plain X-ray findings. We examined the presence and absence of three specific radiological risk factors (MR T2WI confined high-intensity pattern and diffuse low-intensity pattern, thoracolumbar vertebrae involvement, middle column injury) and analyzed clinical outcomes according to numbers of radiological risk factors.

RESULTS

Delayed union was observed in 101 patients (19.9%) at the 6-month follow-up. The most common radiological risk factor was thoracolumbar vertebrae involvement (73.8%), followed by middle column injury (33.9%) and specific MRI findings (T2WI confined high-intensity pattern and diffuse low-intensity pattern) (29.7%). Overall, 85 (16.7%) patients had zero radiological risk factors, 212 (42.7%) had one, 137 (27.0%) had two, and 69 (13.6%) had three. When assessing the number of radiographic risk factors which included the MRI findings (the 3-risk factor method), the odds ratio for delayed union after acute OVF was 5.8 in the 2/3-risk factor group and 13.1 in the 3/3-risk factor group. Even when assessing the number of radiographic risk factors without MRI findings (2-risk factor method), the odds ratio was 3.2 in the 1/2-risk factor group and 10.2 in the 2/2-risk factor group.

CONCLUSION

Number of radiological risk factors added prognostic information for delayed union, kyphotic deformity, and prolonged pain.

Effects of anti-osteoporosis medications on radiological and clinical results after acute osteoporotic spinal fractures: a retrospective analysis of prospectively designed study

Effects of anti-osteoporosis medications such as anti-resorptive and anabolic agents on healing of osteoporotic spinal fracture were retrospectively investigated. The use of anabolic agent significantly enhanced fracture healing, reduced progressive collapse, and presented good pain relief. These findings suggest that proper selection of medication could improve initial management of acute osteoporotic spinal fractures (OSFs).

INTRODUCTION

Although anti-osteoporosis medications have beneficial effects on prevention of osteoporotic spinal fractures (OSFs), few studies have compared effects of medications on fracture healing following OSFs. Therefore, the purpose of this study was to elucidate the effects of different anti-osteoporosis medications on radiological and clinical outcomes after acute OSFs.

METHODS

A total of 132 patients diagnosed with acute OSFs were enrolled and allocated into three groups [group I (n = 39, no anti-osteoporosis medication), group II (n = 66, bisphosphonate), and group III (n = 27, parathyroid hormone (PTH)]. Radiological parameters including magnetic resonance (MR) classification, occurrence of intravertebral cleft (IVC), and clinical outcomes such as numerical rating scale (NRS) and Oswestry disability index were assessed. Risk analyses for IVC and progressive collapse were done along the related factors and medication type.

RESULTS

IVC sign was observed in 30 patients. The rate of IVC sign was lower in group III (7.4%) than that in group I (20.5%) or group II (30.3%), although the difference was not statistically significant. Moreover, the degree of NRS improvement was better in group III than that in group I or group II (5.7 vs. 3.1 vs. 3.5, p < 0.001). On multiple regression analysis, mid-portion type fracture in MR classification was a significant risk factor for progressive OSFs. The use of PTH showed significant lower incidences of occurrence of IVC (odds ratio (OR) = 0.160) and increase in height loss (OR = 0.325).

CONCLUSIONS

Different anti-osteoporosis medications presented different clinical and radiological results after acute OSFs. The use of anabolic agent significantly enhanced fracture healing, reduced progressive collapse, and presented better clinical outcomes. Proper selection of medication might improve initial management of acute OSFs.

Comparison of Rigid and Soft-Brace Treatments for Acute Osteoporotic Vertebral Compression Fracture: A Prospective, Randomized, Multicenter Study

While bracing is the standard conservative treatment for acute osteoporotic compression fracture, the efficacy of different brace treatments has not been extensively studied. We aimed to clarify and compare the preventive effect of the different brace treatments on the deformity of the vertebral body and other clinical results in this patient cohort. This multicenter nationwide prospective randomized study included female patients aged 65–85 years with acute one-level osteoporotic compression fractures. We assigned patients within four weeks of injury to either a rigid-brace treatment or a soft-brace treatment. The main outcome measure was the anterior vertebral body compression percentage at 48 weeks. Secondary outcome measures included scores on the European Quality of Life-5 Dimensions (EQ-5D), visual analog scale (VAS) for lower back pain, and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ). A total of 141 patients were assigned to the rigid-brace group, whereas 143 patients were assigned to the soft-brace group. There were no statistically significant differences in the primary outcome and secondary outcome measures between groups. In conclusion, among patients with fresh vertebral compression fractures, the 12-week rigid-brace treatment did not result in a statistically greater prevention of spinal deformity, better quality of life, or lesser back pain than soft-brace.

Balloon Kyphoplasty Versus Conservative Treatment for Acute Osteoporotic Vertebral Fractures With Poor Prognostic Factors: Propensity Score Matched Analysis Using Data From Two Prospective Multicenter Studies

STUDY DESIGN

A multicenter, prospective, single-arm, intervention study.

OBJECTIVE

The aim of this study was to investigate efficacy of balloon kyphoplasty (BKP) for acute osteoporotic vertebral fractures (OVFs) in patients with poor prognostic factors.

SUMMARY OF BACKGROUND DATA

The indications for BKP remain unclear. Characteristic magnetic resonance imaging (MRI) findings (high-intensity or diffuse low-intensity area in fractured vertebrae on T2-weighted images) were reportedly predictive of delayed union.

METHODS

This study enrolled 106 patients with poor prognostic MRI findings who underwent BKP within 2 months after injury, and 116 controls with acute OVFs and the same poor prognostic factors who underwent conservative treatment. Patients were propensity score matched in a logistic regression model adjusted for age, sex, number of baseline old fractures, and fracture level. The primary outcome was reduction in activities of daily living (ADLs) at 6 months after fracture, and the secondary outcomes were improvement in short-form (SF)-36 subscales, back pain visual analog scale (VAS) score, and vertebral body deformity.

RESULTS

A decrease in ADLs occurred in 5.6% of patients in the BKP group and 25.6% of patients in the conservative treatment group (P < 0.001). The SF-36 vitality subscale score improved by 26.9 ± 25.9 points in the BKP group and 14.5 ± 29.4 points in the control group (P = 0.03). The VAS pain score improved by 43.4 ± 34.4 in the BKP group and 52.2 ± 29.8 in the control group (P = 0.44). The vertebral body wedge angle improved by 5.5 ± 6.2° in the BKP group and -6.3 ± 5.0° in the control group (P < 0.0001). The percent vertebral body height improved by 15.2 ± 19.2% in the BKP group and -20.6 ± 14.2% in the control group (P < 0.0001).

CONCLUSION

ADLs, quality of life, and vertebral deformity showed greater improvement with BKP intervention for acute OVF with poor prognostic factors than with conservative treatment at 6 months after injury. Our treatment strategy uses BKP intervention according to the presence or absence of poor prognostic MRI findings.

LEVEL OF EVIDENCE

4.