The intravertebral cleft in benign vertebral compression fracture: the diagnostic performance of non-enhanced MRI and fat-suppressed contrast-enhanced MRI

ACR Appropriateness Criteria® Management of Vertebral Compression Fractures: 2022 Update

Vertebral compression fractures (VCFs) can have a variety of etiologies, including trauma, osteoporosis, or neoplastic infiltration. Osteoporosis related fractures are the most common cause of VCFs and have a high prevalence among all postmenopausal women with increasing incidence in similarly aged men. Trauma is the most common etiology in those >50 years of age. However, many cancers, such as breast, prostate, thyroid, and lung, have a propensity to metastasize to bone, which can lead to malignant VCFs. Indeed, the spine is third most common site of metastases after lung and liver. In addition, primary tumors of bone and lymphoproliferative diseases such as lymphoma and multiple myeloma can be the cause of malignant VCFs. Although patient clinical history could help raising suspicion for a particular disorder, the characterization of VCFs is usually referred to diagnostic imaging. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Patterns of Vertebral Bone Marrow Edema in the Normal Healing Process of Lumbar Interbody Fusion: Baseline Data for Diagnosis of Pathological Events

STUDY DESIGN

Retrospective investigation using a prospectively collected database.

OBJECTIVE

To examine the appearance and characteristics of vertebral bone marrow edema (BME) in the normal healing of lumbar interbody fusion.

SUMMARY OF BACKGROUND DATA

Although BME in pathological spinal conditions has been well-documented, the patterns and characteristics of BME in the normal healing process of spinal fusion remains unexplored.

MATERIALS AND METHODS

We reviewed imaging from 225 patients with normal healing following posterior lumbar interbody fusion or transforaminal lumbar interbody fusion. BME was identified on magnetic resonance imaging at the third postoperative week and categorized with respect to its appearance, including assessment of area and extension within the relevant vertebrae.

RESULTS

Three hundred eighty-nine of the 450 instrumented vertebrae (86.4%) displayed evidence BME. All instances of BME were associated with the area of contact with the endplate. The average extent of BME was 32.7±1.0%. BME within normal healing following interbody fusion could be categorized into four types: no edema (13.6%), anterior corner (36.6%), around-the-cage focal (48.0%), and diffuse (1.8%). Anterior corner BME was significantly associated with instances of single cage placement than in dual cages (42.6% vs. 24.7%, P =0.0002). Single cages had a significantly higher rate of BME than dual cages (92.0% vs. 75.3%, P <0.0001). The extent of BME was significantly greater in the single cage cohort (36.9% vs. 24.2% in dual cages, P <0.0001).

CONCLUSIONS

This serves as the first study demonstrating the patterns of BME associated with normal healing following lumbar interbody fusion procedures. Anterior corner BME and around-the-cage focal BME were the most common patterns encountered, with diffuse BME a relatively rare pattern. These findings might contribute to the better differentiation of postoperative pathological events from normal healing following lumbar interbody fusion.

LEVEL OF EVIDENCE

4.

Development and Internal Validation of Supervised Machine Learning Algorithm for Predicting the Risk of Recollapse Following Minimally Invasive Kyphoplasty in Osteoporotic Vertebral Compression Fractures

Background

The published literatures indicate that patients with osteoporotic vertebral compression fractures (OVCFs) benefit significantly from percutaneous kyphoplasty (PKP), but this surgical technique is associated with frequent postoperative recollapse, a complication that severely limits long-term postoperative functional recovery.

Methods

This study retrospectively analyzed single-segment OVCF patients who underwent bilateral PKP at our academic center from January 1, 2017 to September 30, 2019. Comparing the plain films of patients within 3 days after surgery and at the final follow-up, we classified patients with more than 10% loss of sagittal anterior height as the recollapse group. Univariate and multivariate logistic regression analyses were performed to determine the risk factors affecting recollapse after PKP. Based on the logistic regression results, we constructed one support vector machine (SVM) classifier to predict recollapse using machine learning (ML) algorithm. The predictive performance of this prediction model was validated by the receiver operating characteristic (ROC) curve, 10-fold cross validation, and confusion matrix.

Results

Among the 346 consecutive patients (346 vertebral bodies in total), postoperative recollapse was observed in 40 patients (11.56%). The results of the multivariate logistical regression analysis showed that high body mass index (BMI) (Odds ratio [OR]: 2.08, 95% confidence interval [CI]: 1.58–2.72, p < 0.001), low bone mineral density (BMD) T-scores (OR: 4.27, 95% CI: 1.55–11.75, p = 0.005), presence of intravertebral vacuum cleft (IVC) (OR: 3.10, 95% CI: 1.21–7.99, p = 0.019), separated cement masses (OR: 3.10, 95% CI: 1.21–7.99, p = 0.019), cranial endplate or anterior cortical wall violation (OR: 0.17, 95% CI: 0.04–0.79, p = 0.024), cement-contacted upper endplate alone (OR: 4.39, 95% CI: 1.20–16.08, p = 0.025), and thoracolumbar fracture (OR: 6.17, 95% CI: 1.04–36.71, p = 0.045) were identified as independent risk factors for recollapse after a kyphoplasty surgery. Furthermore, the evaluation indices demonstrated a superior predictive performance of the constructed SVM model, including mean area under receiver operating characteristic curve (AUC) of 0.81, maximum AUC of 0.85, accuracy of 0.81, precision of 0.89, and sensitivity of 0.98.

Conclusions

For patients with OVCFs, the risk factors leading to postoperative recollapse were multidimensional. The predictive model we constructed provided insights into treatment strategies targeting secondary recollapse prevention.

Posterior Fixation Combined with Vertebroplasty or Vertebral Column Resection for the Treatment of Osteoporotic Vertebral Compression Fractures with Intravertebral Cleft Complicated by Neurological Deficits

Purpose

The aim of the current study was to evaluate the relative benefits of posterior fixation combined with vertebroplasty (PFVP) or vertebral column resection (PVCR) for osteoporotic vertebral compression fractures (OVCFs) with intravertebral cleft (IVC) complicated by neurological deficits.

Methods

From June 2010 to January 2015, 45 consecutive patients suffering OVCFs with IVC and spinal cord injuries were treated with PFVP or PVCR in our department. The visual analogue scale (VAS) score, anterior vertebral height (AVH), posterior vertebral height (PVH), local kyphotic angle (LKA), and neurologic function were evaluated and compared, and the operative duration, blood loss, and complications were also recorded.

Results

They all achieved excellent pain relief, vertebral height recovery, and kyphosis correction one month after surgery, and no significant differences existed between the two groups. No significant differences were observed between the 1-month postoperative and final follow-up VAS, AVH, and LKA values in the PVCR group (P > 0.05), while AVH and LKA worsened in the PFVP group at the final follow-up (P < 0.05). Similarly, the initial improvements in VAS scores decreased over time (P < 0.05). Neurologic function improved in both groups, and no significant differences were observed between the 2 groups either preoperatively or postoperatively (P > 0.05). The blood loss and operative duration were significantly lower in the PFVP group than those in the PVCR group (P < 0.05).

Conclusion

Compared with PVCR, PFVP had equivalent short-term clinical outcomes with less blood loss and operative duration which can be very beneficial for treating elderly patients with extreme comorbidities in this condition. However, based on the long-term efficacy of pain relief, vertebral height maintenance, and deformity correction, PVCR is a more reasonable choice.

The Prognostic Significance of Pedicle Enhancement from Contrast-enhanced MRI for the Further Collapse in Osteoporotic Vertebral Compression Fractures

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

The aim of this study was to investigate the prognostic significance of contrast-enhanced magnetic resonance imaging (MRI) for detecting pedicle enhancement and predicting future collapse in patients with acute benign osteoporotic vertebral compression fracture (OVCF).

SUMMARY OF BACKGROUND DATA

Traditional morphological classification regarding compression versus burst fractures cannot accurately anticipate the prognosis of further collapse. Identifying subgroups with a higher risk for further collapse may be beneficial in determining the treatment modality, which should be decided immediately after the injury.

METHODS

One hundred fourteen patients with benign OVCFs who, at the onset, underwent contrast-enhanced spine MRI between 2003 and 2016 were retrospectively analyzed. Patients were recruited on the basis of predefined inclusion and exclusion criteria. The primary outcome was the compression progression rate; other potential variables included demographic and clinical characteristics, initial compression rates, and kyphotic angles. In addition, other structural abnormalities on MRI were assessed. The compression progression rates were compared according to pedicle enhancement, and the prognostic significance of pedicle enhancement for further collapse were analyzed.

RESULTS

Further compression progression rates were significantly higher in the pedicle-enhanced (PE) group than in the nonenhanced (NE) group. Multivariate logistic analysis revealed that pedicle enhancement may be associated with further compression progression ≥10%. The vertebral augmentation (VAG) protective effect against collapse was only significant within the PE group, while bone densitometry and patients' mobility were significant only within the NE group. The log-rank test revealed a statistically significant difference in the rates of further collapse ≥10% during the 1 year between the groups.

CONCLUSION

Sign of pedicle enhancement is a potential risk factor for further compression progression. Contrast-enhanced MRI should be performed at the onset to better determine the future risk of collapse and to choose a better treatment modality for benign OVCF patients.

LEVEL OF EVIDENCE

3.

Effect of an intensive conservative therapy with daily teriparatide administration and rehabilitation for osteoporotic delayed vertebral collapse and paralysis

Although patients with osteoporotic delayed vertebral collapse (ODVC) have frequently been treated surgically, the efficacy and limitation of conservative treatment for it have not yet been reported. The purpose of this study was to investigate the effectiveness and limitation of further intensive conservative treatment for patients with ODVC.Patients treated for ODVC from 2011 to 2014 with a follow-up period of more than 1 year were eligible. The fundamental treatment strategy consisted of surgical treatment following intensive conservative treatment with daily teriparatide and rehabilitation for 3 months. We conducted a surgical treatment for patients who could not keep standing position by themselves because of prolonged leg paralysis or intolerable back pain. We performed a logistic regression model in which surgical treatment was set as an objective variable, and other related factors including sex, age, the level of affected vertebrae, the quality of paralysis, changing rate (δ) of spinal canal encroachment, local kyphotic angle, mobility of collapsed vertebrae, EuroQol questionnaires (EQ5D), numerical rating scale (NRS), and Frankel grade as explanatory variables. We also plotted receiver operating curves (ROCs) to investigate the cutoff values of parameters at the baseline.Thirty patients (6 males and 24 females, mean age 76.7 years) were enrolled. Eventually 12 out of 30 patients avoided surgical treatment because their symptoms were improved. Logistic regression showed that δ of local kyphotic angle (odds ratio: 1.072), P = .01), mobility of collapsed vertebrae (1.063, 0.01), EQ5D (0.98, 0.04), and NRS (1.113, 0.01) were significantly correlated with the need for surgical treatments. Among the factors at baseline, only the mobility of collapsed vertebrae showed a significant value of area under a curve (AUC = 0.727, P = .008).The results that 40% of patients with ODVC did not need further surgical treatment after the intensive conservative treatment was of great significance. Patients with greater mobility of collapsed vertebrae might be treated surgically as quickly as possible.

Progression of Vertebral Compression Fractures After Previous Vertebral Augmentation: Technical Reasons for Recurrent Fractures in a Previously Treated Vertebra

It is well recognized that patients can develop additional vertebral compression fractures (VCF) in an adjacent vertebra or at another vertebral level after successful vertebral augmentation. Factors such as the patient's bone mineral density, post procedure activity, and chronic corticosteroid use contribute to an increased risk of re-fracture or development of new fractures in the first three months after the initial procedure. However, there is a very small subgroup of patients that have unchanged or worse pain after the vertebral augmentation that may indicate continued progression of the treated compression fracture or a recurrent fracture at the previously treated level. This review examines the clinical findings, radiologic signs, and intraprocedural technical failures that may occur during the initial vertebral augmentation that can lead to a progressive fracture in a previously treated vertebra. Causes of failure of the initial vertebral augmentation procedure include inadequate or incomplete filling of the fracture site, the cement missing the actual fracture allowing continued osteoporotic compression, and persistent or worsened intravertebral fluid-filled clefts. The existence of an unfilled intravertebral fluid cleft on preoperative diagnostic studies is the most important indicator of risk for progression as is the later development of fluid at the bone cement interface.

Treating osteoporotic vertebral compression fractures with intraosseous vacuum phenomena using high-viscosity bone cement via bilateral percutaneous vertebroplasty

Osteoporotic vertebral compression fractures with intraosseous vacuum phenomena could cause persistent back pains in patients, even after receiving conservative treatment. The aim of this study was to evaluate the efficacy of using high-viscosity bone cement via bilateral percutaneous vertebroplasty in treating patients who have osteoporotic vertebral compression fractures with intraosseous vacuum phenomena.Twenty osteoporotic vertebral compression fracture patients with intraosseous vacuum phenomena, who received at least 2 months of conservative treatment, were further treated by injecting high-viscosity bone cement via bilateral percutaneous vertebroplasty due to failure of conservative treatment. Treatment efficacy was evaluated by determining the anterior vertebral compression rates, visual analog scale (VAS) scores, and Oswestry disability index (ODI) scores at 1 day before the operation, on the first day of postoperation, at 1-month postoperation, and at 1-year postoperation.Three of 20 patients had asymptomatic bone cement leakage when treated via percutaneous vertebroplasty; however, no serious complications related to these treatments were observed during the 1-year follow-up period. A statistically significant improvement on the anterior vertebral compression rates, VAS scores, and ODI scores were achieved after percutaneous vertebroplasty. However, differences in the anterior vertebral compression rate, VAS score, and ODI score in the different time points during the 1-year follow-up period was not statistically significant (P > 0.05).Within the limitations of this study, the injection of high-viscosity bone cement via bilateral percutaneous vertebroplasty for patients who have osteoporotic vertebral compression fractures with intraosseous vacuum phenomena significantly relieved their back pains and improved their daily life activities shortly after the operation, thereby improving their life quality. In this study, the use of high-viscosity bone cement reduced the leakage rate and contributed to their successful treatment, as observed in patients during the 1-year follow-up period.

What Effects Does Necrotic Area of Contrast-Enhanced MRI in Osteoporotic Vertebral Fracture Have on Further Compression and Clinical Outcome?

Objective

The objective of this study was to analyze the correlation between further compression and necrotic area in osteoporotic vertebral fracture (OVF) patients with contrast-enhanced magnetic resonance imaging (CEMRI). In addition, we investigated the radiological and clinical outcome according to the range of the necrotic area.

Methods

Between 2012 and 2014, the study subjects were 82 OVF patients who did not undergo vertebroplasty or surgical treatment. The fracture areas examined on CEMRI at admission were defined as edematous if enhancement was seen and as necrotic if no enhancement was seen. The correlation between further compression and the necrotic and edematous areas of CEMRI, age, and bone mineral density was examined. Also, necrotic areas were classified into those with less than 25% (non-necrosis group) and those with more than 25% (necrosis group) according to the percentages of the entire vertebral body. For both groups, further compression and the changes in wedge and kyphotic angles were examined at admission and at 1 week, 3 months, and 6 months after admission, while the clinical outcomes were compared using the visual analog scale (VAS) and Eastern Cooperative Oncology Group (ECOG) performance status grade.

Results

Further compression was 14.78±11.11% at 1 month and 21.75±14.43% at 6 months. There was a very strong correlation between the necrotic lesion of CEMRI and further compression (r=0.690, p<0.001). The compression of the necrosis group was 33.52±12.96%, which was higher than that of the non-necrosis group, 14.96±10.34% (p<0.005). Also, there was a statistically significantly higher number of intervertebral cleft development and surgical treatments being performed in the necrosis group than in the non-necrosis group (p<0.005). Moreover, there was a statistical difference in the decrease in the height of the vertebral body, and an increase was observed in the kyphotic change of wedge angle progression. There was also a difference in the VAS and ECOG performance scales.

Conclusion

The necrotic area of CEMRI in OVF had a strong correlation with further compression over time. In addition, with increasing necrosis, intervertebral clefts occurred more frequently, which induced kyphotic changes and resulted in poor clinical outcomes. Therefore, identifying necrotic areas by performing CEMRI on OVF patients would be helpful in determining their prognosis and treatment course.

Time course of osteoporotic vertebral fractures by magnetic resonance imaging using a simple classification: a multicenter prospective cohort study

This study revealed the time course of osteoporotic vertebral fracture by magnetic resonance imaging using a simple classification. Signal changes were associated with the compression degree and mobility of the fractured vertebral body. This classification showed sufficient reliability in categorizing magnetic resonance imaging findings of osteoporotic vertebral fractures.

INTRODUCTION

Magnetic resonance imaging (MRI) is useful in diagnosing osteoporotic vertebral fractures (OVFs). This study investigated the time course of OVFs by MRI using a simple classification.

METHODS

This multicenter cohort study was performed from 2012 to 2015. Consecutive patients with ≤2-week-old OVFs were enrolled in 11 institutions. MRI was performed at enrollment and at 1-, 3-, 6-, and 12-month follow-up. Signal changes on T1-weighted imaging (T1WI), T2WI, and short τ inversion recovery (STIR) were classified according to signal intensity. Height and angular motion of vertebral bodies were also measured.

RESULTS

The 6-month follow-up was completed by 153 patients. At enrollment, fractured vertebrae signal changes were 43 % diffuse and 57 % confined low on T1WI; on T2WI, 56, 24, and 5 % were confined low, high, and diffuse low, respectively; on STIR, 100 % were high. On T1WI, diffuse low remained most common (90 % at 1 month and 60 % at 3 months) until 6 and 12 months, when most were confined low (54 and 52 %, respectively). On T2WI, confined low remained most common (decreasing to 41 % at 12 months). On STIR, high signal change was shown in 98, 87, and 64 % at 3, 6, and 12 months, respectively. At 3, 6, and 12 months, diffuse low signal change was associated with significantly lower vertebral height, and high signal change was associated with significantly greater angular motion.

CONCLUSIONS

MRI signal changes were associated with the compression degree and angular motion of fractured vertebrae. This classification showed sufficient reliability in categorizing MRI findings of OVFs.

Early Bone Marrow Edema Pattern of the Osteoporotic Vertebral Compression Fracture : Can Be Predictor of Vertebral Deformity Types and Prognosis?

Objective

To evaluate whether an early bone marrow edema pattern predicts vertebral deformity types and prognosis in osteoporotic vertebral compression fracture (OVCF).

Methods

This retrospective study enrolled 64 patients with 75 acute OVCFs who underwent early MRI and followed up MRI. On early MRI, the low SI pattern of OVCF on T1WI were assessed and classified into 3 types (diffuse, globular or patchy, band-like). On followed up MRI, the vertebral deformity types (anterior wedge, biconcave, crush), degree of vertebral body height loss, incidence of vertebral osteonecrosis and spinal stenosis were assessed for each vertebral fracture types.

Results

According to the early bone marrow edema pattern on T1WI, 26 vertebrae were type 1, 14 vertebrae were type 2 and 35 vertebrae were type 3. On followed up MRI, the crush-type vertebral deformity was most frequent among the type 1 OVCFs, the biconcave-type vertebral deformity was most frequent among the type 2 OVCFs and the anterior wedge-type vertebral deformity was most frequent among the type 3 OVCFs (p<0.001). In addition, type 1 early bone marrow edema pattern of OVCF on T1WI were associated with higher incidence of severe degree vertebral body height loss, vertebral osteonecrosis and spinal stenosis on the follow up MRI.

Conclusion

Early bone marrow edema pattern of OVCF on T1WI, significant correlated with vertebral deformity types on the follow up MRI. The severe degree of vertebral height loss, vertebral osteonecrosis, and spinal stenosis were more frequent in patients with diffuse low SI pattern.

Therapeutic effects of PKP on chronic painful osteoporotic vertebral compression fractures with or without intravertebral cleft

This study aims to investigate clinical effects of protruding after percutaneous vertebral plasty (PKP holds) for treatment of chronic painful osteoporotic vertebral compression fractures (CPOVCFs), and assess its safety and effectiveness. One hundred and eighteen CPOVCFs patients were included, and analyzed and followed up therapeutic effects of PKP holds. All of these patients were divided into NIVC (73 cases) and IVC (45 cases) group. Comparing operation time, bone cement perfusion, pain intensity modulus visual grading scoring, Oswestry disability index, fracture fanterior relative height, local convex Angle, and surgical complications between the two groups. There were no significant differences between two groups for operation time of PKP holds (P>0.05). Amount of bone cement injection in IVC groups was significantly higher compared to NIVC group (P<0.05). Pain intensity visual modulus ratings and Oswestry disability index were significantly improved in both groups after surgery and postoperative follow-up period compared to pre-operation (P<0.05). Fracture fanterior margin relative height and local convex angle were also significantly improved (P<0.05). Fracture fanterior margin relative height was also significantly improved for IVC compared to NIVC group (P<0.05). There were no differences for bone cement leakage rate and adjacent segment fracture between two groups (P>0.05). But there was a case of bone cement loose, which needs to be treated for further step. In conclusion, PKP holds is a kind of effective and safe method for the IVC and NIVC patients. Especially for the IVC patients, PKP holds can significantly improve the fracture fanterior margin relative height.

Basivertebral foramen could be connected with intravertebral cleft: a potential risk factor of cement leakage in percutaneous kyphoplasty

BACKGROUND CONTEXT

Among different types of cement leakage in percutaneous kyphoplasty (PKP) for osteoporotic vertebral body compression fractures, leaks into the spinal canal are considered to be the most common complication. One potential structure causing this type of cement leakage is the potential connection between the basivertebral foramen and the intravertebral cleft, which is revealed clearly on magnetic resonance (MR) images, but is often ignored in the literature.

PURPOSE

The purpose of this study is to assess the incidence rate of different types of cement leakage in PKP with or without intravertebral clefts and to determine whether the basivertebral foramen could be connected to the intravertebral cleft.

STUDY DESIGN

This study is a retrospective assessment of the presence of an intravertebral cleft in osteoporotic vertebral bodies and the different types of cement leakage after PKP on radiographs, computed tomographic (CT) scans, and MR images.

PATIENT SAMPLE

A total of 164 consecutive patients underwent PKP to treat 204 osteoporotic vertebral compression fractures.

OUTCOME MEASURES

Outcome measures include the occurrence of different types of cement leakage in the groups with an intravertebral cleft and without intravertebral clefts.

METHODS

A total of 204 vertebrae in 164 consecutive patients who underwent PKP to treat osteoporotic vertebral compression fractures were classified into two patterns based on preoperative radiographs, CT scans, and/or MR images of the treated levels: cleft pattern (with an intravertebral cleft in the vertebral body) and trabecular pattern (without intravertebral clefts). When an intravertebral cleft was identified, the investigators examined the basivertebral foramen and looked for a communication between the two structures on three-dimensional CT scans and MR images. On direct postoperative images, the patterns of cement leakage were classified as five types: type A, through a cortical defect into the paraspinal soft tissues; type B, through the basivertebral foramen; type C, via the needle channel; type D, through a cortical defect into the disc space; and type E, via the paravertebral vein. The association of the distribution of the cement leakage and the presence of an intravertebral cleft was analyzed retrospectively. Moreover, the association of type B leakage with the communication between the basivertebral foramen and the intravertebral cleft was also assessed.

RESULTS

The average interobserver kappa values for determining the type of cement leakage and the presence of intravertebral cleft were 0.916 (range, 0.792-1) and 0.935, respectively. In 41 of 204 vertebrae (19.9%), an intravertebral cleft was confirmed on preoperative images. A communication between the intravertebral cleft and the basivertebral foramen was seen in 10 vertebrae (24.4%). Cement leakage was 36.2% in the group with a trabecular pattern and 41.5% in the group with a cleft pattern (p>.05). Leaks through the basivertebral foramen (type B; N=30, 14.7%) and through cortical defects into the disc space (type D; N=14, 6.9%) were more common than other types. Twenty of 163 vertebrae with the trabecular pattern (12.3%) and 10 of 41 vertebrae with the cleft pattern (24.4%) were identified as type B leaks, which reached statistical significance (p<.05). There was no statistical difference between the trabecular pattern and the cleft pattern on other types of leaks.

CONCLUSIONS

Type B leaks are more common in vertebrae with an intravertebral cleft, which supports the presence of a connection between an intravertebral cleft and the basivertebral foramen. Thus, care must be taken when PKP is performed in these patients to avoid direct cement leakage into the spinal canal through the basivertebral foramen.

Percutaneous balloon kyphoplasty of osteoporotic vertebral compression fractures with intravertebral cleft

BACKGROUND

Intravertebral cleft is a structural change in osteoporotic vertebral compression fractures (OVCF), which is the manifestation of ischemic vertebral osteonecrosis complicated with fracture nonunion and pseudoarthrosis and appears in the late stage of OVCF. Despite numerous studies on OVCF, few aim to evaluate the clinicoradiological characteristics and clinical significance of intravertebral cleft in OVCF. This study investigates clinicoradiological characteristics of intravertebral cleft in OVCF and the effect on the efficacy of percutaneous balloon kyphoplasty (PKP).

MATERIALS AND METHODS

PKP was performed on 139 OVCF patients without intravertebral cleft (group A) and 44 OVCF patients with intravertebral cleft (group B). The frequency distribution of the affected vertebral body, bone cement infusion volume, imaging manifestation, leakage rate and type, preoperative and postoperative height of the affected vertebral body, visual analog scale (VAS) and Oswestry disability index (ODI) score were evaluated.

RESULTS

Significant differences were found in the frequency distribution of the affected vertebral body and bone cement leakage type between the two groups (P < 0.05). However, differences in bone cement infusion volume and leakage rate (P > 0.05) were not detected. In both groups, the postoperative height of the affected vertebral body was significantly improved (P < 0.05). The restoration of vertebral body height in group B was more evident than that in group A (P < 0.05). The preoperative VAS and ODI scores in group B were significantly higher than those in group A (P < 0.05). After surgical treatment, pain relief and daily activity function in both groups were significantly improved (P < 0.05), and no significant difference in postoperative scores was detected between the two groups (P > 0.05).

CONCLUSION

Intravertebral cleft exhibits specific clinical and imaging as well as bone cement formation characteristics. PKP can effectively restore the affected vertebral body height, alleviate pain, and improve daily activity function of patients.

Contrast-enhanced MRI for detecting intravertebral cleft formation: relation to the time since onset of vertebral fracture

OBJECTIVE

The purpose of this study was to investigate the advantages of contrast-enhanced MRI (CE-MRI) for detecting intravertebral clefts over unenhanced MRI in relation to the time since onset of vertebral fracture.

MATERIALS AND METHODS

In this retrospective study, a total of 115 patients (88 women, 27 men; mean age, 77.1 years) who underwent percutaneous vertebroplasty for a single-level compression fracture within 7 days of preprocedural MRI were enrolled. Two radiologists evaluated preprocedural unenhanced MRI (T1-weighted and STIR) and CE-MRI examinations for intravertebral clefts on separate days by consensus. The time from the onset of fracture to MRI was classified into three groups: early phase fractures (< 1 month), late phase fractures (1-3 months), and chronic phase fractures (≥ 3 months). The cement distribution during percutaneous vertebroplasty was used as a reference standard, and detectability of clefts was compared between unenhanced MRI and CE-MRI in relation to the time frame. An analog of the McNemar test was used for analyses.

RESULTS

There were 104 patients (90.4%) with and 11 patients (9.6%) without a cleft. The sensitivities of unenhanced MRI and CE-MRI, respectively, for detecting clefts were 60.9% and 91.3% for early phase fractures (p = 0.02); 78.6% and 100% for late phase fractures (p = 0.014); and 92.5% and 94.3% for chronic phase fractures (p = 0.3). The specificities were the same for both groups (100% for each time frame).

CONCLUSION

CE-MRI is more sensitive than unenhanced MRI for detecting intravertebral clefts in patents with benign compression fractures less than 3 months old.