Management of thoracolumbar spine fractures

Synthetic lumbar MRI can aid in diagnosis and treatment strategies based on self-pix networks

CT and MR tools are commonly used to diagnose lumbar fractures (LF). However, numerous limitations have been found in practice. The aims of this study were to innovate and develop a spinal disease-specific neural network and to evaluate whether synthetic MRI of the LF affected clinical diagnosis and treatment strategies. A total of 675 LF patients who met the inclusion and exclusion criteria were included in the study. For each participant, two mid-sagittal CT and T2-weighted MR images were selected; 1350 pairs of LF images were also included. A new Self-pix based on Pix2pix and Self-Attention was constructed. A total of 1350 pairs of CT and MR images, which were randomly divided into a training group (1147 pairs) and a test group (203 pairs), were fed into Pix2pix and Self-pix. The quantitative evaluation included PSNR and SSIM (PSNR1 and SSIM1: real MR images and Pix2pix-generated MR images; PSNR2 and SSIM2: real MR images and Self-pix-generated MR images). The qualitative evaluation, including accurate diagnosis of acute fractures and accurate selection of treatment strategies based on Self-pix-generated MRI, was performed by three spine surgeons. In the LF group, PSNR1 and PSNR2 were 10.884 and 11.021 (p < 0.001), and SSIM1 and SSIM2 were 0.766 and 0.771 (p < 0.001), respectively. In the ROI group, PSNR1 and PSNR2 were 12.350 and 12.670 (p = 0.004), and SSIM1 and SSIM2 were 0.816 and 0.832 (p = 0.005), respectively. According to the qualitative evaluation, Self-pix-generated MRI showed no significant difference from real MRI in identifying acute fractures (p = 0.689), with a good sensitivity of 84.36% and specificity of 96.65%. No difference in treatment strategy was found between the Self-pix-generated MRI group and the real MRI group (p = 0.135). In this study, a disease-specific GAN named Self-pix was developed, which demonstrated better image generation performance compared to traditional GAN. The spine surgeon could accurately diagnose LF and select treatment strategies based on Self-pix-generated T2 MR images.

Differential diagnostic value of radiomics models in benign versus malignant vertebral compression fractures: A systematic review and meta-analysis

PURPOSE

Early diagnosis of benign and malignant vertebral compression fractures by analyzing imaging data is crucial to guide treatment and assess prognosis, and the development of radiomics made it an alternative option to biopsy examination. This systematic review and meta-analysis was conducted with the purpose of quantifying the diagnostic efficacy of radiomics models in distinguishing between benign and malignant vertebral compression fractures.

METHODS

Searching on PubMed, Embase, Web of Science and Cochrane Library was conducted to identify eligible studies published before September 23, 2023. After evaluating for methodological quality and risk of bias using the Radiomics Quality Score (RQS) and the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2), we selected studies providing confusion matrix results to be included in random-effects meta-analysis.

RESULTS

A total of sixteen articles, involving 1,519 vertebrae with pathological-diagnosed tumor infiltration, were included in our meta-analysis. The combined sensitivity and specificity of the top-performing models were 0.92 (95 % CI: 0.87-0.96) and 0.93 (95 % CI: 0.88-0.96), respectively. Their AUC was 0.97 (95 % CI: 0.96-0.99). By contrast, radiologists' combined sensitivity was 0.90 (95 %CI: 0.75-0.97) and specificity was 0.92 (95 %CI: 0.67-0.98). The AUC was 0.96 (95 %CI: 0.94-0.97). Subsequent subgroup analysis and sensitivity test suggested that part of the heterogeneity might be explained by differences in imaging modality, segmentation, deep learning and cross-validation.

CONCLUSION

We found remarkable diagnosis potential in correctly distinguishing vertebral compression fractures in complex clinical contexts. However, the published radiomics models still have a great heterogeneity, and more large-scale clinical trials are essential to validate their generalizability.

Trends in Spinal Orthosis Utilization Among Patients Insured Through Medicare Part B

STUDY DESIGN

Retrospective population-based database analysis from the Physician/Supplier Procedure Summary Medicare/Medicaid Data Set.

OBJECTIVE

To provide a comprehensive analysis of trends in spinal orthosis utilization over a 12-year period.

SUMMARY OF BACKGROUND DATA

Widespread prescription of spinal orthosis persists, despite evidence suggesting equivocal efficacy in many spinal conditions. The utilization of spinal orthosis on a national level, including prescribing specialty data, has not been previously analyzed.

MATERIALS AND METHODS

Health care common procedure coding system codes for cervical (CO), thoracic-lumbar-sacral (TLSO), lumbar (LO), lumbar-sacral (LSO), and cervical-thoracic-lumbar-sacral (CTLSO) orthosis were used to determine spinal orthosis utilization from 2010 to 2021. Provider specialty codes were utilized to compare trends between select specialties. In addition, a neurosurgical CO analysis based on subclassifications of cervical bracing was performed. Linear trendlines were implemented to elucidate and present trends by slope (β).

RESULTS

Among 332,241 claims, decreases in CO (β=-0.3387), TLSO (β=-0.0942), LO (β=-0.3485), and LSO (β=-0.1545) per 100,000 Medicare Part B enrollees and CTLSO (β=-0.052) per 1,000,000 Medicare Part B enrollees were observed. Decreases among neurosurgery (β=-7.9208), family medicine (β=-1.0097), emergency medicine (β=-2.1958), internal medicine (β=-1.1151), interventional pain management (β=-5.0945), and chiropractic medicine (β=-49.012), and increases among orthopedic surgery (β=5.5891), pain management (β=30.416), physical medicine and rehabilitation (β=4.6524), general practice (β=79.111), and osteopathic manipulative medicine (β=45.303) in total spinal orthosis use per 100,000 specialty claims were observed. Analysis of subclassifications of cervical orthosis among neurosurgeons revealed decreases in flexible (β=-1.7641), semirigid (β=-0.6157), and collar bracing (β=-2.7603), and an increase in multipost collar bracing (β=2.2032) per 100 neurosurgical cervical orthosis claims.

CONCLUSIONS

While utilization of spinal orthosis decreased between 2010 and 2021, increased utilization was observed among a subset of specialties. Identifying these specialties allows for focused research and educational efforts to minimize unnecessary durable medical equipment use for effective health care spending.

Age was a protective factor for unexpected malignant diagnoses in patients with vertebral compression fracture

OBJECTIVE

The purpose was to investigate the risk factors for unexpected malignant diagnoses in patients with vertebral compression fractures (VCF).

METHODS

The clinical data were retrospectively collected from 1396 patients who underwent vertebral augmentation and biopsy between 2012 and 2022. According to the imaging results, the preoperative diagnoses were benign VCF (BVCF) in all these cases. Based on the histological findings, the patients were divided into two groups. In group A, unexpected malignant VCF (MVCF) was identified, while benign VCF (BVCF) was verified in group B. Logistic regression analysis was performed to analyze the risk and protective factors for unexpected malignant diagnoses.

RESULTS

There were 44 patients in group A and 1352 in group B. The incidence of unexpected MVCF was 3.2 %. Age was significantly lower in group A compared to group B. Additionally, none of the patients in group A were older than 75. Age was associated with unexpected malignant diagnoses, according to the univariate logistic analysis. The multivariate logistic analysis showed that age was a protective factor for unexpected malignant diagnoses (odds ratio = 0.849, 95 % confidence interval: 0.809-0.891, p < 0.01).

CONCLUSION

Age was a protective factor for unexpected malignant diagnoses in patients with preoperative diagnosis of BVCF. A routine biopsy is recommended to be performed during vertebral augmentation in young patients without preoperative imaging evidence of MVCF.

A4 Thoracolumbar Fracture Class Is Associated With a Greater Degree of Vertebral Height Loss in Conservatively Managed Patients

INTRODUCTION

Thoracolumbar (TL) junction fractures are common, often resulting from high-energy trauma or osteoporosis, and may lead to neurological deficits, deformities, or chronic pain. Treatment decisions for neurologically intact patients remain controversial, with nonsurgical management often favored. The AO classification system has been used to characterize thoracolumbar fractures using fracture morphology and clinical factors affecting clinical decision-making for fracture management. This study aims to assess the radiographic outcomes of utilizing a thoracolumbosacral orthosis (TLSO) brace in neurologically intact patients with TL fractures based on the AO classification system.

METHODS

A retrospective analysis of 43 patients was conducted using data from the VCU Spine Database on patients with TL fractures managed conservatively with a TLSO brace from 2010 to 2019. Demographic variables and radiographic measurements of anterior height loss were analyzed and stratified by AO fracture class.

RESULTS

Significant differences were observed in anterior height loss between AO fracture classes, with A4 fractures showing significantly greater anterior height loss at initial presentation (27.6 + 4.8%) compared to A1/A2 (16.1 + 2.2%; p=0.049). At follow up, A4 fractures had a significantly greater anterior height loss (40.2 + 6.6%) than both the A1/A2 (22.4 + 2.9%; p=0.029) and A3 fracture classes (20.5 + 3.6; p=0.020).

CONCLUSIONS

The study highlights significant differences in anterior height loss among AO fracture classes, suggesting varying degrees of severity and potential implications for clinical management. While conservative treatment with TLSO braces may provide pain relief, surgical intervention may offer better structural recovery, especially in more severe fractures. Conservative management of TL fractures with TLSO braces may result in greater anterior height loss, particularly in A4 fractures, emphasizing the need for individualized treatment decisions. Further research, including prospective studies, is warranted to validate these findings and guide clinical practice effectively.

Biomechanical Effect of Different Posterior Fixation Techniques on Stability and Adjacent Segment Degeneration in Treating Thoracolumbar Burst Fracture With Osteoporosis: A Finite Element Analysis

STUDY DESIGN

Finite element analysis.

OBJECTIVE

To investigate the biomechanical effect of four posterior fixation techniques on stability and adjacent segment degeneration in treating thoracolumbar burst fractures with osteoporosis.

SUMMARY OF BACKGROUND DATA

In terms of stability and adjacent segment degeneration, there remains no consensus or guidelines on the optimal technique for the treatment of thoracolumbar burst fractures in patients with osteoporosis.

MATERIALS AND METHODS

Images of CT scans were imported into MIMICS and further processed by Geomagic to build three-dimensional models of the T10-L5 region. A v-shaped osteotomy was performed on the L1 vertebral body to simulate a burst fracture in the setting of osteoporosis. Subsequently, four fixation techniques were designed using SolidWorks software. Range of motion (ROM) of the global spine, ROM distribution, ROM of adjacent segment, Von Mises stress on adjacent intervertebral disks, and facet joints were analyzed.

RESULTS

Among the four groups, the cortical bone screw fixation (CBT) showed the highest global ROM at 1.86°, while long-segmented pedicle screw fixation (LSPS) had the lowest global ROM at 1.25°. The LSPS had the smallest percentage of ROM of fractured vertebral body to fixed segment at 75.04%, suggesting the highest stability after fixation. The maximum ROM of the adjacent segment was observed in the CBT at 1.32°, while the LSPS exhibited the smallest at 0.89°. However, the LSPS group experienced larger maximum stress on the adjacent intervertebral disks (9.60 MPa) and facet joints (3.36 MPa), indicating an increasing risk of adjacent segment disease.

CONCLUSION

LSPS provided the greatest stability, while CBT provided the smallest amount of stability. However, the elevated stress on adjacent intervertebral disks and facet joints after LSPS fixation increased the possibility of adjacent segment degeneration. Cement-augmented pedicle screw fixation (CAPS) and combined cortical bone screw and pedicle screw fixation (CBT-PS) demonstrated significant biomechanical advantages in providing moderate fixation strength while reducing stress on the intervertebral disks and facet joints.

How reliable is the distinction between thoracolumbar AO type A3 and A4 fractures? A systematic literature review

PURPOSE

The AOSpine classification divides thoracolumbar burst fractures into A3 and A4 fractures; nevertheless, past research has found inconsistent interobserver reliability in detecting those two fracture patterns. This systematic analysis aims to synthesize data on the reliability of discriminating between A3 and A4 fractures.

METHODS

We searched PubMed, Scopus, and the Web of Science for studies reporting the inter- and intra-observer reliability of detecting thoracolumbar AO A3 and A4 fractures using computed tomography (CT). The search spanned 2013 to 2023 and included both primarily reliability and observational comparative studies. We followed the PRISMA guidelines and used the modified COSMIN checklist to assess the studies' quality. Kappa coefficient (k) values were categorized according to Landis and Koch, from slight to excellent.

RESULTS

Of the 396 identified studies, nine met the eligibility criteria; all were primarily reliability studies except one observational study. Interobserver k values for A3/A4 fractures varied widely among studies (0.19-86). The interobserver reliability was poor in two studies, fair in one study, moderate in four studies, and excellent in two studies. Only two studies reported intra-observer reliability, showing fair and excellent agreement. The included studies revealed significant heterogeneity in study design, sample size, and interpretation methods.

CONCLUSION

Considerable variability exists in interobserver reliability for distinguishing A3 and A4 fractures from slight to excellent agreement. This variability might be attributed to methodological heterogeneity among studies, limitations of reliability analysis, or diagnostic pitfalls in differentiating between A3 and A4. Most observational studies comparing the outcome of A3 and A4 fractures do not report interobserver agreement, and this should be considered when interpreting their results.

3D-CT reconstruction for pedicle outer width assessment in patients with thoracolumbar spine fractures: a comparative analysis between age groups <60 years and ≥60 years

Objective

This study aims to compare the utilization of 3D-CT reconstruction in measuring pedicle outer width (POW) between younger/middle-aged patients (<60 years) and older patients (≥60 years) with thoracolumbar spine fractures (TSF).

Methods

We conducted a retrospective study from January 2021 to December 2022, involving a total of 108 patients with TSF. The study population consisted of 62 patients aged ≥60 years (observation group) and 46 patients aged <60 years (control group). We compared the POW on both the right and left sides of the thoracolumbar spine between the two groups. Additionally, we analyzed the POW by gender within each group and calculated the incidence of patients falling below the critical values for arch root puncture (5 mm) and arch root nailing (7 mm) in both groups.

Results

There were no statistically significant differences observed in the POW between the two groups on both the left and right sides of each corresponding vertebra (P > 0.05). In the observation group, both male and female patients had significantly smaller POW compared to the control group (P < 0.05). However, no significant difference in POW was observed between the same-sex groups in the L4 to L5 vertebrae (P > 0.05). In the observation group, the POW was less than 5 mm in 9.33% (81/868) of cases and less than 7 mm in 49.88% (433/868) of cases, primarily observed from T11 to L3. In the control group, 4.81% (31/644) of cases had a POW of less than 5 mm, and 13.81% (88/644) had a POW of less than 7 mm.

Conclusion

Utilizing preoperative 3D-CT reconstruction to measure POW in patients with TSF not only facilitates the assessment of surgical feasibility but also aids in surgical pathway planning, thus potentially reducing the incidence of postoperative complications.

The Comparison between Spinal Facet Joint Toothed Plate and Traditional Pedicle Screw-rod on Reduction of Thoracolumbar Fracture

OBJECTIVE

Thoracolumbar fractures are one of the most common fractures in clinical practice. Surgical intervention is recommended to restore spinal alignment or decompress the nerves when there are unstable fractures or neurological injuries. However, after excessive forward thrust force restoration, facet joint dislocation often occurs between the upper vertebra and the fractured vertebra, which usually leads to unsatisfactory reduction outcomes. Herein, we propose a novel spinal facet joint toothed plate to assist in fracture reduction. The purpose of this study is to evaluate the effectiveness of the new spinal facet joint toothed plate in preventing facet joint dislocation, and its advantages compared to traditional pedicle screw-rod decompression.

METHODS

A total of 26 patients in the toothed plate group and 93 patients in the traditional group who experienced thoracolumbar fracture with reduction were retrospectively included. Relevant patients' information and clinical parameters were collected. Furthermore, visual analogue scores (VAS) scores and Oswestry disability index (ODI) scores were also collected. Moreover, imaging parameters were calculated based on radiographs. Correlated data were analyzed by χ2 test and t test.

RESULTS

All patients in this study had no postoperative complications. Postoperative VAS scores and ODI scores (p < 0.001) were statistically significant (p < 0.001) in both groups compared with preoperative scores and further decreased (p < 0.001) at final follow-up. In addition, the postoperative vertebral margin ratio (VMR) (p < 0.001) and vertebral angle of the injured vertebrae (p < 0.001) were significantly improved compared with the preoperative period. There were no significant differences in postoperative VAS scores and ODI scores between the two groups. However, toothed plate reduction significantly improved the VMR (p < 0.05) and vertebral angle (p < 0.05) compared with conventional reduction. Ultimately, the total screw accuracy was 98.72% (sum of levels 0 and I), with 100% screw accuracy in the segment related to the tooth plate in the tooth plate group. The dislocation rate was higher in the conventional group (6.45%) than in the new serrated plate repositioning group (0.00%).

CONCLUSION

The facet toothed plate assisted reduction method prevents facet joint dislocation and improves fracture reduction compared to traditional reduction technique, hence it could be considered as a novel surgical strategy for thoracolumbar fracture reduction.

Prevalence, Implications, and Risk Factors of Traumatic Dural Tears in Thoracic and Lumbar Fractures: A Retrospective Study

Introduction Spine fracture in association with traumatic dural tear is a serious injury. A traumatic dural tear is difficult to determine based on initial clinical presentation and radiological imaging even with magnetic resonance imaging (MRI). However, during decompression surgery, cerebrospinal fluid leaks surrounding the injured segments are usually confirmed by directly visualizing them. For preoperative planning and intraoperatively limiting further damage to the dural and neurological structures, early detection of traumatic dural tears before surgery is important. This study aims to determine the prevalence, implication, risk factors, and complications of traumatic dural tears in patients who have undergone surgical treatment for thoracic and lumbar fractures. We believe our retrospective study would identify more accurate risk factors for traumatic dural tears and aid us with preoperative planning and operative precaution. Methods This study retrospectively included all patients who had thoracic and lumbar fractures and had posterior instrumentation and decompression surgery at three hospitals in the Northern region of Malaysia from January 2018 to December 2020. Fractures associated with pathological spine including metastatic, severe osteoporosis, ankylosing spondylitis, metabolic bone disease, those with missing data, and iatrogenic dural tears were excluded from this study. Preoperative and postoperative neurological assessments based on the American Spinal Injury Association (ASIA) impairment scale, blood loss volume, duration of the surgery, and post-surgery complications were gathered from medical records. Interpedicular distance, ratio of central canal diameter, laminar fracture gap, and pedicle fractures were identified and measured. The obtained data was analyzed using Pearson's chi-square and Fisher's exact test for categorical variables, and independent t-test/Mann-Whitney test for numerical variables. Result This study comprised a total of 93 patients who had fractures in their thoracic and lumbar regions. The mean age of the patients was 38 years. The number of patients with traumatic dural tears was 20 (21.5%). There was an association between the presence of dural tears and preoperative neurological deficits (P<0.001). Wider mean interpedicular distance (P=0.004), increased central canal diameter ratio (P<0.001), and displaced laminar fracture (P<0.001) were significantly higher in patients with traumatic dural tears. Multiple logistic regression analysis showed both incomplete (P=0.002) and complete (P=0.037) preoperative neurological deficit, increase of central diameter ratio of encroachment (P=0.011), and presence of >2mm laminar fracture gap (P=0.015) had a significant association with a traumatic dural tear. This study found that patients with traumatic dural tears had longer surgical times and statistically larger mean blood loss volumes when compared to patients without dural tears (P<0.001). There is no significant association between the complications following the surgery and the presence of a dural tear (P>0.05).  Conclusion This study shows that the presence of preoperative neurological deficits, wider interpedicular distance, severe canal encroachment, and wide separation of laminar fracture may indicate the likelihood of traumatic dural tear in spine fracture. These factors will enable surgeons to enhance their operational planning and make early preparations for the management of dural tears.

Modified 5-Item Frailty Index: A Useful Tool for Assessing the Impact of Frailty on Postoperative Morbidity and Mortality Following Surgical Fixation of Thoracolumbar Fractures

OBJECTIVES

The modified 5-item frailty index (mFI-5) is a comorbidity-based risk stratification tool to predict adverse events following various neurologic surgeries. This study aims to quantify the association between increased mFI-5 and postoperative complications and mortality following surgical fixation of traumatic thoracolumbar fractures.

METHODS

The 2011-2021 American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) dataset was used to identify patients undergoing fusion surgeries for thoracolumbar spine fractures. The mFI-5 score was calculated based on the presence of 5 major comorbidities: congestive heart failure within 30 days before surgery, insulin-dependent or noninsulin-dependent diabetes mellitus, chronic obstructive pulmonary disease, partially dependent or totally dependent functional health status at the time of surgery, and hypertension requiring medication. Multivariate analysis assessed the independent impact of increasing mFI-5 scores on postoperative 30-day morbidity and mortality while controlling for baseline clinical characteristics.

RESULTS

A total of 66,904 patients were included in our analysis (54.2% female, mean age 62.27 ± 12.93 years). On univariate analysis, higher mFI-5 score was significantly associated with increased risks of superficial surgical site infection, deep surgical site infection, wound dehiscence, unplanned reoperation, pneumonia, unplanned intubation, postoperative ventilator use, progressive renal insufficiency, acute renal failure, urinary tract infection, stroke, myocardial infarction, cardiac arrest, pulmonary embolism, deep vein thrombosis, bleeding requiring transfusion, sepsis, septic shock, and longer hospital length of stay (LOS). On multivariate logistic regression, increasing mFI-5 score versus a mFI-5 score of zero was associated with higher odds of overall complications (mFI-5 ≥2: odds ratio [OR] 1.38 CI: 1.24-1.54, P < 0.001; mFI-5 = 1: OR 1.18 CI: 1.11-1.24, P < 0.001) and 30-day mortality (mFI-5 ≥2: OR 2.33 CI: 1.60-3.38, P < 0.001).

CONCLUSION

This study demonstrates that frailty, when measured using the mFI-5, independently predicts postoperative complications, hospital LOS, and 30-day mortality after surgical repair of thoracolumbar fractures. These findings are important for risk stratification in patients undergoing thoracolumbar fusion surgery and for standardization in reporting outcomes after those procedures.

Progress and research trends in neurogenic bladder after spinal cord injury bibliometric analysis based on web of science database: An observational study

Neurogenic bladder (NB) is a significant complication that often occurs after spinal cord injury. It results from urinary dysfunction caused by the injury, disrupting the normal neural control of the bladder and urethra. Symptoms of NB can include urinary frequency, urgency, incontinence, and retention, all of which can greatly impact the quality of life of affected individuals. While there are articles and reviews on NB, fewer specifically address NB following spinal cord injury. This study examined 1095 publications from January 1, 2000, to March 27, 2024, in the Web of Science core database using bibliometric software like VOSviewer, CiteSpace, and Bibliometrics. The analysis revealed an increasing trend in the number of publications, with the United States and China leading in research output. Professor Jeremy B. Myers from the University of Utah had the highest number of publications, while the University of Michigan and the University of Pittsburgh were the institutions with the most publications. The journal Neurourology and Urodynamics had the highest number of articles, and common keywords included management, quality of life, and dysfunction, highlighting key areas of focus for scholars.

Efficacy and Safety of Conservative Treatment Compared With Surgical Treatment for Thoracolumbar Fracture With Score 4 Thoracolumbar Injury Classification and Severity (TLICS): A Systematic Review and Meta-analysis

STUDY DESIGN

This was a systematic review and meta-analysis.

OBJECTIVE

The clinical outcomes, radiologic outcome, and complications were compared between surgical treatment and conservative treatment of thoracolumbar fractures with a Thoracolumbar Injury Classification and Severity (TLICS) score of 4.

SUMMARY OF BACKGROUND DATA

The thoracolumbar fracture is the main reason leading to the spinal cord injury. Some studies suggested that the treatment of TLICS=4 is a "gray zone." Hence, the efficacy and safety of surgical treatment and conservative treatment of thoracolumbar fractures with scores 4 TLICS was still debated.

MATERIALS AND METHODS

A comprehensive search of PubMed, Embase, and the Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Chongqing VIP Database (VIP), and Wan Fang Database was performed up to October 2021. Relevant studies were identified using specific eligibility criteria and data was extracted and analyzed based on primary and secondary outcomes.

RESULTS

A total of 10 studies involving 555 patients were included (3 randomized controlled trials and 7 retrospective studies). There was no significant difference of hospital time (standardized mean difference=0.24, 95% CI: -1.50 to 1.97, P =0.79) and Oswestry Disability Index (mean difference=2.97, 95% CI: -1.07 to 7.01, P =0.15) between surgery and nonsurgery. The length of returning to work was shorter in surgical treatment (standardized mean difference=1.27, 95% CI: 0.07-2.46, P =0.04). Visual Analog Scale in surgical treatment was lower at 1, 3, and 6 months (respectively, P <0.00001, P =0.003, and P =0.02). However, there existed no significant difference between surgical treatment and nonsurgical treatment at 12 and >24 months (respectively, P =0.18 and 0.17). Cobb angle was lower in surgical treatment at postoperative at 6, 12, and >24 months (respectively, P =0.005, P <0.00001, P =0.002, and P =0.0002). Finally, the surgical treatment had a lower incidence of complications (odds ratio=3.89, 95% CI: 1.90-7.94, P =0.0002).

CONCLUSIONS

Current evidence recommended that surgical treatment is superior to conservative treatment of TLICS score of 4 at the early follow-up. Surgical treatment had lower Cobb angle, Visual Analog Scale scores, and complications compared with a nonsurgical TLICS score of 4. However, these findings needed to be verified further by multicenter, double-blind, and large-sample randomized controlled trials.

Factors associated with loss of vertebral height and kyphosis correction after intermediate screws in short segment pedicular fixation for type-A fractures of the thoracolumbar spine: A retrospective study

In this article, we attempted to identify risk factors affecting the loss of vertebral height and kyphosis correction on type A thoracolumbar fractures. Patients with type A thoracolumbar fractures who underwent short segments with intermediate screws at the fracture level management between 2017 and 2022 were included in this study. Clinical factors including patients' demographic characteristics (age, sex), history (smoking, hypertension and/or diabetes), value of height/kyphosis correction, the thoracolumbar injury classification and severity score (TLICS), the load sharing classification (LSC) scores and bone mineral density were collected. Correlation coefficient, simple linear regression analysis and multivariate regression analysis were performed to identify the clinical factors associated with the loss of vertebral height/kyphosis correction. Finally, 166 patients were included in this study. The mean height and kyphosis correction were 21.8% ± 7.5% and 9.9° ± 3.8°, respectively, the values of the loss were 6.5% ± 4.0% and 3.9° ± 1.9°, respectively. Simple linear regression analysis and multivariate regression analysis showed that age, value of height correction, LSC scores and bone mineral density were significantly associated with the loss of vertebral height and kyphosis correction (P < .01) We could draw the conclusion that patients with older age, lower bone mineral density, higher LSC scores and diabetes are at higher risk of vertebral height and kyphosis correction loss increase. For these patients, appropriate clinical measures such as long segment fixation, control of blood glucose, and increase of bone density must be taken to reduce the loss of correction.

Prevalence, Features, and Predictive Factors of Spontaneous Spinal Arthrodesis in Posttraumatic Thoracolumbar Kyphosis

OBJECTIVE

Spontaneous spinal arthrodesis (SSA) is a phenomenon of spontaneous fusion, and SSA is not rare in posttraumatic thoracolumbar kyphosis (PTK). However, few reports have focused on SSA in patients with PTK. The objective of this study was to investigate the prevalence, features, and predictive factors of SSA in patients with PTK.

METHODS

In this retrospective study, 70 patients with PTK were included. Data on the clinical and radiologic parameters were obtained and evaluated. According to whether there was SSA or not, patients were divided into an SSA group (n = 45) or a non-SSA group (n = 25). A binary logistic regression analysis was used to identify the predictive factors for SSA.

RESULTS

The incidence of SSA in PTK was 64%. Among 45 patients with PTK with SSA, SSA was present as a solid bridging anterior osteophyte along the vertebral bodies in 11 patients, posterior contiguous bony growth through the facet joints bilaterally in 13 patients, bony formation in both anterior and posterior elements in 18 patients, and direct contiguous bony formation from the injured vertebral body to the adjacent one in 3 patients. Patients with longer disease duration, larger local Cobb angle, and anterior wall height loss (AWHL) ratio of injured vertebral body, and less kyphosis flexibility index were significantly more likely to develop SSA. The parameter of AWHL remained significant in binary logistic regression analysis.

CONCLUSIONS

SSA in PTK was common, and the SSA sign presented in various patterns, which might have implications for surgical decisions. AWHL was the independent predictor for SSA.

Reliability of thoracolumbar burst fracture classification in the Swedish Fracture Register

BACKGROUND

The Swedish Fracture Register (SFR) is a national quality register for all types of fractures in Sweden. Spine fractures have been included since 2015 and are classified using a modified AOSpine classification. The aim of this study was to determine the accuracy of the classification of thoracolumbar burst fractures in the SFR.

METHODS

Assessments of medical images were conducted in 277 consecutive patients with a thoracolumbar burst fracture (T10-L3) identified in the SFR. Two independent reviewers classified the fractures according to the AOSpine classification, with a third reviewer resolving disagreement. The combined results of the reviewers were considered the gold standard. The intra- and inter-rater reliability of the reviewers was determined with Cohen's kappa and percent agreement. The SFR classification was compared with the gold standard using positive predictive values (PPV), Cohen's kappa and percent agreement.

RESULTS

The reliability between reviewers was  high (Cohen's kappa 0.70-0.97). The PPV for correctly classifying burst fractures in the SFR was high irrespective of physician experience (76-89%), treatment (82% non-operative, 95% operative) and hospital type (83% county, 95% university). The inter-rater reliability of B-type injuries and the overall SFR classification compared with the gold standard was low (Cohen's kappa 0.16 and 0.17 respectively).

CONCLUSIONS

The SFR demonstrates a high PPV for accurately classifying burst fractures, regardless of physician experience, treatment and hospital type. However, the reliability of B-type injuries and overall classification in the SFR was found to be low. Future studies on burst fractures using SFR data where classification is important should include a review of medical images to verify the diagnosis.

A Critical Appraisal of the Congress of Neurological Surgeons Evidence-Based Guidelines on the Evaluation and Treatment of Patients With Thoracolumbar Spine Trauma

Background and objective Thoracolumbar spine trauma (TST) is frequently associated with spinal cord injury and other soft tissue and bony injuries. The management of such injuries requires an evidence-based approach. This study used the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument to assess the methodological quality of clinical guidelines for the management of TST published by the Congress of Neurological Surgeons (CNS). Methods All clinical guidelines on TST published by CNS until 2020 were assessed. Five appraisers from three international centers evaluated the quality of eligible clinical guidelines by using AGREE II. Mean AGREE II scores for each domain were determined. In higher-quality domains, the scores for individual items were analyzed. Results A total of 12 guidelines published by CNS on TST were assessed. Mean scores for all six domains were as follows: Scope and Purpose (75.2%), Stakeholder Involvement (45.4%), Rigor of Development (57.0%), Clarity of Presentation (58.7%), Applicability (16.9%), and Editorial Independence (64.1%). The mean score for the overall quality of all CNS guidelines was 52.9% [95% confidence interval (CI): 52.2-53.5%]. The overall agreement among appraisers was excellent [intra-class correlation coefficients (ICCs) for each guideline ranged from 0.903 to 0.963]. Conclusions CNS guidelines for the management of TST demonstrated acceptable quality across most domains; however, the domains of Applicability and Stakeholder Involvement could be further improved in future guideline updates. The assessors concluded that all guidelines could still be recommended for clinical practice with or without modifications.

AI-based automated detection and stability analysis of traumatic vertebral body fractures on computed tomography

PURPOSE

We developed and tested a neural network for automated detection and stability analysis of vertebral body fractures on computed tomography (CT).

MATERIALS AND METHODS

257 patients who underwent CT were included in this Institutional Review Board (IRB) approved study. 463 fractured and 1883 non-fractured vertebral bodies were included, with 190 fractures unstable. Two readers identified vertebral body fractures and assessed their stability. A combination of a Hierarchical Convolutional Neural Network (hNet) and a fracture Classification Network (fNet) was used to build a neural network for the automated detection and stability analysis of vertebral body fractures on CT. Two final test settings were chosen: one with vertebral body levels C1/2 included and one where they were excluded.

RESULTS

The mean age of the patients was 68 ± 14 years. 140 patients were female. The network showed a slightly higher diagnostic performance when excluding C1/2. Accordingly, the network was able to distinguish fractured and non-fractured vertebral bodies with a sensitivity of 75.8 % and a specificity of 80.3 %. Additionally, the network determined the stability of the vertebral bodies with a sensitivity of 88.4 % and a specificity of 80.3 %. The AUC was 87 % and 91 % for fracture detection and stability analysis, respectively. The sensitivity of our network in indicating the presence of at least one fracture / one unstable fracture within the whole spine achieved values of 78.7 % and 97.2 %, respectively, when excluding C1/2.

CONCLUSION

The developed neural network can automatically detect vertebral body fractures and evaluate their stability concurrently with a high diagnostic performance.

Comparison of the Clinical Outcomes of Vesselplasty vs. Percutaneous Vertebroplasty for the Treatment of Neurologically Intact Osteoporotic Kümmell's Disease: A Retrospective Study

Kummell's disease (KD) is a rare clinical complication of osteoporotic vertebral compression fractures (OVCFs). Minimally invasive surgery is an important way to treat KD. In this paper, we used Percutaneous Vertebroplasty (PVP) and Vesselplasty (VP) to treat KD. 125 patients with KD were admitted to our hospital. Among them, 89 patients received PVP and 36 received VP. All patients underwent operations successfully. VAS scores and ODI of both groups at each postoperative time point were lower than preoperatively. Postoperative Cobb angle of both groups postoperatively was lower than preoperatively (p < 0.05). The anterior height and ratio of vertebra compression of both groups postoperatively was lower than preoperatively (p < 0.05). Cement leakage occurred in 16 vertebrae (16/89) in PVP group and one (1/36) in VP group. Two patients suffered from transient paraplegia in PVP group immediately after operation. Adjacent vertebral fractures occurred in one patient in PVP group and one in VP group. Re-fracture of affected vertebra occurred in one patient in PVP group. Besides, four patients suffered from bone cement loosening in PVP group while one in VP group. Both PVP and VP play an important effect in pain relief and functional recovery for the treatment of KD. And VP is more effective than PVP in preventing cement leakage.

Towards a standardized reporting of the impact of magnetic resonance imaging on the decision-making of thoracolumbar fractures without neurological deficit: Conceptual framework and proposed methodology

Introduction

A recent meta-analysis showed that only four prior studies have shown that magnetic resonance imaging (MRI) can change the fracture classification in 17% and treatment decisions in 22% of cases. However, previous studies showed a wide methodological variability regarding the study population, the definition of posterior ligamentous complex (PLC) injury, and outcome measures.

Research question

How can we standardize the reporting of the impact of MRI for neurologically intact patients with thoracolumbar fractures?

Material and methods

All available literature regarding the impact of MRI on thoracolumbar fracture classification or decision-making were reviewed. Estimating the impact of MRI on the TLFs' classification is an exercise of analyzing the CTs' accuracy for PLC injury against MRI as a ''Gold standard''and should follow standardized checklists such as the Standards for the Reporting of Diagnostic Accuracy Studies. Additionally, specific issues related to TLFs should be addressed.

Results

A standardized approach for reporting the impact of MRI in neurologically intact TLF patients was proposed. Regarding patient selection, restricting the inclusion of neurologically intact patients with A- and B-injuries is crucial. Image interpretation should be standardized regarding imaging protocol and appropriate criteria for PLC injury. The impact of MRI can be measured by either the rate of change in fracture classification or treatment decisions; the cons and pros of each measure is thoroughly discussed.

Discussion and conclusion

We proposed a structured methodology for examining the impact of MRI on neurologically intact patients with TLFs, focusing on appropriate patient selection, standardizing image analysis, and clinically relevant outcome measures.

Acute Translation Fracture of the Lumbar Spine With Increased Motoric Outcomes: A Case Report

Translation fracture of the lumbar spine is a rare but serious condition that necessitates prompt medical attention. This injury can cause nerve damage, spinal cord compression, and other complications that can affect motor function. The motoric outcomes of this fracture type depend on a variety of factors, including the severity and location of the fracture, the age and general health of the patient, and the timeliness and effectiveness of treatment. Accurate diagnosis and treatment of these injuries is important to prevent further neurological damage and improve motoric outcomes. Here we present the case of a male patient with a translation fracture at the L1-L2 level with AO spine type C who underwent immediate realignment and posterior stabilization, and subsequently participated in an early rehabilitation program, resulting in improved neurologic function. Thoracolumbar fracture with lateral dislocation is very rare and significant experience is needed to determine which management strategy can ensure the best outcome.

Unilateral Pediculectomy and Reduction with Short-Segment Pedicle Screw Fixation for Thoracolumbar Burst Fracture: A Case Series

BACKGROUND

This study aimed to evaluate the efficacy of unilateral pediculectomy and reduction with short-segment pedicle screw fixation for thoracolumbar burst fracture.

METHODS

We retrospectively reviewed patients who underwent a unilateral pediculectomy and reduction with short-segment fixation and interbody fusion for thoracolumbar burst fracture. The unilateral pediculectomy created sufficient space to approach the ventral side of the spinal cord for removing bone fragments and insertion of an interbody cage to correct kyphosis. Lumbar lordosis (LL), pelvic incidence (PI) minus LL, and segmental Cobb angle were measured at 3 time points: preoperatively, postoperatively, and final follow-up. Furthermore, sagittal vertical axis (SVA) was measured to assess global sagittal balance at the final follow-up.

RESULTS

A total of 10 patients, with a mean age of 39.8 ± 21.0, underwent the surgical procedure. All patients had a thoracolumbar injury classification and severity score > 5. The mean follow-up period was 15.8 ± 13.9 months. The mean postoperative LL (46.0 ± 5.8) was significantly higher (P = 0.008) than the preoperative measurement (32.8 ± 8.2). The mean postoperative PI minus LL (2.2 ± 8.4) was not significantly lower (P = 0.051) than preoperative measurement (15.4 ± 12.6). The mean postoperative segmental Cobb angle (11.4 ± 8.4) was significantly higher (P < 0.001) than the preoperative measurement (-11.6 ± 10.9). At the final follow-up, the mean sagittal vertical axiswas 10.0 ± 28.8 mm.

CONCLUSIONS

Unilateral pediculectomy and reduction with short-segment fixation and interbody fusion served as an efficient surgical method for thoracolumbar burst fracture.

Finite element analysis of different pedicle screw internal fixations for first lumbar vertebral fracture in different sports conditions

OBJECTIVE

Lumbar fractures are the most common spinal injuries, and surgery is required for severe fracture. This study aimed to investigate the variations in motion and stress in varying states of activity after minimally invasive and traditional open pedicle screw placement for L1 vertebral fracture stabilization.

METHODS

We studied a male volunteer (26 years old) with no history of chronic back pain or lumbar spine trauma. We used the finite element method for this investigation. Using finite element software, we created a three-dimensional model of L1 vertebral compression fracture. We also constructed models for four percutaneous pedicle screws spanning the fractured vertebra and four screws traversing the damaged vertebra with transverse fixation.

RESULTS

In all three-dimensional movement directions, the open pedicle fixation system experienced maximum stress higher than its percutaneous counterpart. With axial spinal rotation, von Mises stress on the traditional open pedicle screw was considerably lower than that with percutaneous pedicle fixation, but peak stress was elevated at the transverse connection. Traditional open pedicle fixation displayed less maximum displacement than percutaneous pedicle internal fixation.

CONCLUSIONS

During axial spinal movements, high peak stress is observed at the transverse connection. Patients should avoid excessive axial rotation of the spine during recovery.

Can You Feel it? - Correlation Between Intraoperatively Perceived Bone Quality and Objectively Measured Bone Mineral Density

STUDY DESIGN

clinical study.

OBJECTIVES

Loosening of pedicle screws is a frequent complication in patients with osteoporosis. The indication for additional stabilization, such as cement augmentation, is more often based on the subjective intraoperative feeling of the surgeon than on a preoperative bone mineral density (BMD) measurement. Aim was to evaluate the correlation of the intraoperative perceived bone quality in comparison to the objectively measured BMD.

METHODS

A total of 62 patients undergoing dorsal stabilization using pedicle screws at a level-1 trauma center were analyzed. The preoperative CT scan measured each instrumented vertebra's pedicle size and BMD. During the surgery, the perceived screw stability was graded by the respective surgeon for each screw.

RESULTS

204 vertebral bodies were evaluated. Looking at all implanted screws a significant correlation between the measured BMD and the perceived screw stability was found (Resident r = .450; R2 = .202; P < .001/Attending r = .364; R2 = .133; P < .001), but there was no significant correlation in the osteoporotic patients (Resident P = .148 / Attending P = .907). The evaluation of the screws implanted in osteoporotic vertebrae showed that the surgeons considered a total of 31% of these screws to be sufficiently stable.

CONCLUSIONS

There was no significant correlation between the measured BMD and the perceived pedicle screw stability in the group with osteopenic / osteoporotic bone (<100 mg/cm³). The results indicate that it is not possible to reliably determine the bone quality and the resulting screw stability in patients with reduced BMD. The preoperative measurement of the BMD should become a crucial part of preoperative planning.

Assessment of Health-Related Quality of Life in Patients With Traumatic Fractures Following Thoracolumbar Fusion: Short-Term Results

INTRODUCTION

Thoracolumbar vertebral fractures (TVFs) constitute frequent injuries with specific therapeutic challenges and remarkable implications for affected individuals. The aim of this study is to investigate the alteration of overall health-related quality of life (HRQoL) in patients with traumatic TVFs undergoing thoracolumbar fusion surgery.

MATERIALS AND METHODS

A total of 72 patients with single-level traumatic thoracic or lumbar vertebral fractures (AO type A3 or A4) were enrolled in this prospective cohort study. All patients were subjected to thoracolumbar spinal fusion surgery with or without posterior decompression, being followed up for a two-year period. Clinical assessment was conducted via the implementation of the Visual Analog Scale (VAS) and 36-item Short-Form Survey Questionnaire (SF-36) for the evaluation of pain and HRQoL, respectively. Patient assessment was performed in determined postoperative follow-up intervals.

RESULTS

Recorded values of assessed outcome measures demonstrated a statistically significant improvement during the entire two-year follow-up period. This improvement was more pronounced throughout the first three to six postoperative months, subsequently demonstrating a plateau. No statistically significant correlation between age, SF-36, and VAS was found, with the exception of the bodily pain index, the improvement of which was observed to be positively correlated with age. Transient causalgia and cerebrospinal fluid leak were recorded in 5% of evaluated individuals.

CONCLUSIONS

Thoracolumbar fusion constitutes a safe and efficient option for the surgical management of single-level traumatic vertebral fractures. Nevertheless, rehabilitation is a lasting procedure that may last over six months until final amelioration is observed. Clinical improvement may be more pronounced in older patients, potentially due to different expectations.

Percutaneous Pedicle Screw for Thoracolumbar Fractures: A Long-term Follow-up

Objective:  This is a retrospective cohort study to analyze the long-term outcomes of thoracolumbar spine fracture patients who underwent minimally invasive percutaneous fixation. Methods:  The cases of 17 patients with thoracolumbar spine fractures who had percutaneous fixation between 2009 and 2011 were the subject of a retrospective analysis. Clinical and radiographic variables were collected. For the clinical evaluation the questionnaires SF-36 and Oswestry were used. Radiographic parameters were evaluated using fracture's classification based on Magerls's criteria, the fractured vertebra's wedging angle, and the affected segment's segmental Cobb angle. The measures were made at different stages: before surgery, immediately after surgery, one year later, and at a late follow-up (5 years later). Trauma associated injuries, post-surgical and implant related complications were among the additional information taken into account. Results:  The SF-36 questionnaire showed averages above 63,5% in all domains in the late postoperative data (from 5 years after the surgery). Oswestry questionnaire answers showed minimal or no physical limitations in 80% of the patients with a mean score of 10,8%±10,5. The average preoperative Cobb angle value was 5,53° ± 13,80° of kyphosis, the immediate postoperative 2,18° ± 13,38° of kyphosis, one year postoperative 5,26 ± 13,95° of kyphosis, and the late follow-up 8,78° ± 15,06° of kyphosis. The mean correction was 3,35°, and mean loss of correction was 6,6°. There were no complications observed, no case of neurological deficit, infection or implant failure occurred. Conclusion:  Thoracolumbar vertebrae fractures can be surgically treated with positive late clinical and radiological outcomes and low complication rates using a minimally invasive percutaneous method.

Return to sports/activity level after 360° thoracolumbar fusion after burst fractures in young patients

Introduction

Traumatic thoracolumbar burst fractures are the most common spinal injuries and the proper treatment is controversial. In central Europe in particular, these fractures are often treated with minimally invasive anterior-posterior reduction and fusion, whereas a conservative approach is preferred in the USA. Independent of the treatment strategy, no data exists regarding the outcome related to return to activity level/sport.

Research question

The aim of this study was to evaluate the return to sports and activity levels after 360° fusion in patients with thoracolumbar burst fractures without neurological deficits.

Methods

Between January 2013 and December 2022, 46 patients aged 18 to 40 years underwent partial or complete vertebral body replacement in the thoracolumbar region due to traumatic burst fractures without neurologic deficit as an isolated injury. Patients were contacted retrospectively by phone calls to assess their activities using a modified version of the Tegner activity scale at different time points: Before trauma, 3, 6, and 12 months post-surgery.

Results

After applying exclusion criteria, data collection was complete for 28 patients. The median modified Tegner activity scale was 5.4 before sustaining the fracture, declined to 2.9 at three months post-trauma, improved to 4.2 at six months, and reached 5.0 at 12 months. The majority (83%) of patients achieved their pre-accident activity level within 12 months. No significant differences were observed between patients with partial or complete corpectomy.

Conclusion

This is the first study assessing return to sports/physical activity based on the modified Tegner scale in young patients undergoing 360° fusion for spinal burst fractures. The majority of patients (83%) return to the pre-injury activity level within 12 months after surgery.

Percutaneous monoplanar screws versus hybrid fixed axial and polyaxial screws in intermediate screw fixation for traumatic thoracolumbar burst fractures: a case-control study

BACKGROUND

To compare the clinical and radiological outcomes of monoplanar screws (MSs) versus hybrid fixed axial and polyaxial screws (HSs) in percutaneous short-segment intermediate screw fixation (PSISF) for traumatic thoracolumbar burst fractures (TTBFs) in patients without neurologic impairment.

METHODS

A consecutive series of 100 patients with single-segment TTBFs and no neurologic impairment who underwent PSISF with 6 monoplanar screws (MS group) or correct were retrospectively enrolled. The demographic data, radiologic evaluation indicators, perioperative indicators and clinical assessment indicators were analysed between the MS group and HS group.

RESULTS

The demographic data and perioperative indicators were not significantly different in the two groups (P > 0.05). The postoperative anterior vertebral height ratio (AVHR), kyphosis Cobb angle (KCA), vertebral wedge angle (VWA) and spinal canal encroachment rate (SCER) were significantly improved in both groups (*P < 0.05). The MS group obtained better correction than the HS group in terms of improvement in the AVHR, KCA and VWA after surgery (*P < 0.05). At the last follow-up, the MS group had less correction loss of AVHR, KCA and VWA (*P < 0.05). The MS group presented greater improvement in the SCER at the last follow-up (*P < 0.05). The visual analogue scale (VAS) score and Oswestry Disability Index (ODI) score of all patients were significantly better postoperatively than those preoperatively (*P < 0.05), and the scores collected at each follow-up visit did not differ significantly between the two groups (P > 0.05). In the MS group, no internal fixation failure was observed during the follow-up period, but, in the HS group, two cases of internal fixation failure were observed at the last follow-up (one case of rod loosening and one case of screw breakage).

CONCLUSIONS

Both MSs and HSs fixation are effective treatments for TTBFs and have comparable clinical outcomes. In contrast, MSs fixation can improve the correction effect, better improve the SCER, and further reduce correction loss as well as reduce the incidence of instrumentation failure. Therefore, MSs fixation might be a better option for treating TTBFs in patients without neurological deficits.

Experimentally Validated Finite Element Analysis of Thoracic Spine Compression Fractures in a Porcine Model

Vertebral compression fractures (VCFs) occur in 1 to 1.5 million patients in the US each year and are associated with pain, disability, altered pulmonary function, secondary vertebral fracture, and increased mortality risk. A better understanding of VCFs and their management requires preclinical models that are both biomechanically analogous and accessible. We conducted a study using twelve spinal vertebrae (T12-T14) from porcine specimens. We created mathematical simulations of vertebral compression fractures (VCFs) using CT scans for reconstructing native anatomy and validated the results by conducting physical axial compression experiments. The simulations accurately predicted the behavior of the physical compressions. The coefficient of determination for stiffness was 0.71, the strength correlation was 0.88, and the failure of the vertebral bodies included vertical splitting on the lateral sides or horizontal separation in the anterior wall. This finite element method has important implications for the preventative, prognostic, and therapeutic management of VCFs. This study also supports the use of porcine specimens in orthopedic biomechanical research.

Increased stability due to symmetric cement volume in augmented pedicle screws? A biomechanical study

Pedicle screw instrumentation has become "state of the art" in surgical treatment of many spinal disorders. Loosening of pedicle screws due to poor bone mineral density is a frequent complication in osteoporotic patients. As prevalence of osteoporosis and spinal disorders are increasing with an aging demographic, optimizing the biomechanical properties of pedicle screw constructions and therefore outcome after spinal surgery in osteoporotic patients is a key factor in future surgical therapy. Therefore, this biomechanical study investigated the stability of polymethylmethacrylate (PMMA)-augmented pedicle screw-rod constructions under a deviating distribution of PMMA applied to the instrumentation in osteoporotic human cadaveric vertebrae. We showed that PMMA-augmented pedicle screw-rod constructions tend to be more stable than those with non-augmented pedicle screws. Further, there appears to be a larger risk of screw loosening in unilateral augmented pedicle screws than in non-augmented, therefore a highly asymmetrically distributed PMMA should be avoided.

Is restoration of vertebral body height after vertebral body fractures and minimally-invasive dorsal stabilization with polyaxial pedicle screws just an illusion?

INTRODUCTION

Thoracolumbar spine fractures often require surgical treatment as they are associated with spinal instability. Optimal operative techniques and treatment are discussed controversially. Aim of our prospective cohort study was to investigate the sagittal alignment after reduction, the secondary loss of reduction and the subjective outcome as well as the causal correlation of these parameters after minimally invasive stabilization of thoracic and lumbar fractures with polyaxial pedicle screws.

MATERIALS AND METHODS

In a single-center study, a total of 78 patients with an average age of 61 ± 17 years who suffered a fracture of the thoracic or lumbar spine were included and subjected to a clinical and radiological follow-up examination after 8.5 ± 8 months. The kyphotic deformity was measured by determining the vertebral body angle, the mono- and bi-segmental wedge angle at three time points. The patients' subjective outcome was evaluated by the VAS spine score.

RESULTS

After surgical therapy, a significant reduction of the traumatic kyphotic deformity was shown with an improvement of all angles (vertebral body angle: 3.2° ± 4.4°, mono- and bi-segmental wedge angle: 3.1° ± 5.6°, 2.0° ± 6.3°). After follow-up, a significant loss of sagittal alignment was observed for all measured parameters with a loss of correction. However, no correlation between the loss of reduction and the subjective outcome regarding the VAS spine scale could be detected.

CONCLUSION

The minimally invasive dorsal stabilization of thoracic and lumbar spine fractures with polyaxial pedicle screws achieved a satisfactory reduction of the fracture-induced kyphotic deformity immediately postoperatively with a floss of reduction in the further course. However, maybe the main goal of this surgical procedure should be the prevention of a complete collapse of the vertebral body instead of a long-lasting restoration of anatomic sagittal alignment.

LEVEL OF EVIDENCE

II.

Long-segment versus short-segment fixation through a posterior approach for tuberculous spondylodiscitis of the mid-thoracic spine in adults: a study of mid- to long-term efficacy

BACKGROUND

This retrospective study aimed to perform a comparative evaluation of the mid- to long-term efficacy of long-segment and short-segment fixations via the posterior approach as a treatment for tuberculous spondylodiscitis in the mid-thoracic spine.

METHODS

A total of 95 patients with tuberculous spondylodiscitis in the mid-thoracic spine underwent surgery via the posterior approach including single-stage posterior debridement, interbody fusion, and pedicle screw fixation. Long-segment fixations were performed for 46 patients (group A), while short-segment fixations were performed for the other 49 patients (group B). Clinical and radiological outcomes were assessed during mid- to long-term follow-up.

RESULTS

The average follow-up periods for groups A and B were 75.5±11.8 and 76.8±11.6 months, respectively. The operative time and intraoperative blood loss were lower in group B than in group A (P<0.05). Both management approaches significantly corrected the kyphotic deformity detected either in the early postoperative period or at the final visit after long-term follow-up (P>0.05). Bony fusion was generated after average periods of 10.8±2.1 months and 11.0±2.0 months in groups A and B, respectively. Favorable outcomes were observed on assessment of neurological function and patients' well-being at the final follow-up.

CONCLUSIONS

No therapeutic differences were observed between long-segment and short-segment fixation as surgical treatment for mid-thoracic Pott's disease during mid- to long-term follow-up. Kyphotic deformity and neurological impairment were significantly relieved via both posterior fixation approaches, with patients' well-being reaching a favorable level. Moreover, short-segment fixation led to less blood loss and required a shorter operative time.

Traumatic spinal injury-related hospitalizations in the United States, 2016-2019: a retrospective study

BACKGROUND

Traumatic spinal injury (TSI) is associated with significant fatality and social burden; however, the epidemiology and treatment of patients with TSI in the US remain unclear.

MATERIALS AND METHODS

An adult population was selected from the National Inpatient Sample database from 2016 to 2019. TSI incidence was calculated and TSI-related hospitalizations were divided into operative and nonoperative groups according to the treatments received. TSIs were classified as fracture, dislocation, internal organ injury, nerve root injury, or sprain injuries based on their nature. The annual percentage change (APC) was calculated to identify trends. In-hospital deaths were utilized to evaluate the prognosis of different TSIs.

RESULTS

Overall, 95 047 adult patients were hospitalized with TSI in the US from 2016 to 2019, with an incidence rate of 48.4 per 100 000 persons in 2019 (95% CI: 46.2-50.6). The total incidence increased with an APC of 1.5% (95% CI: 0.1-3%) from 2016 to 2019. Operative TSI treatment was more common than nonoperative (32.8 vs. 3.8; 95% CI: 32.3-33.2 vs. 3.6-4%). The number of operations increased from 37 555 (95% CI: 34 674-40 436) to 40 460 (95% CI: 37 372-43 548); however, the operative rate only increased for internal organ injury (i.e. spinal cord injury [SCI])-related hospitalizations (APC, 3.6%; 95% CI: 2.8-4.4%). In-hospital mortality was highest among SCI-related hospitalizations, recorded at 3.9% (95% CI: 2.9-5%) and 28% (95% CI: 17.9-38.2%) in the operative and nonoperative groups, respectively.

CONCLUSIONS

The estimated incidence of TSI in US adults increased from 2016 to 2019. The number of operations increased; however, the proportion of operations performed on TSI-related hospitalizations did not significantly change. In 2019, SCI was the highest associated mortality TSI, regardless of operative or nonoperative treatment.

Complex Compression Fracture in the Thoracolumbar Junction: A Case Report

Compression fractures in the thoracolumbar junction are one of the most frequent types of spine injuries. They can be the result of trauma or underlying conditions of the vertebrae. We present a case report of a 68-year-old patient with pain and loss of mobility in the lumbar spine after sustaining a trauma via falling from a significant height. Lumbar spondylography and a following CT scan revealed a complex compression fracture of L1 with degenerative osteoporotic changes of lumbar vertebrae and several pathologies of the lumbosacral junction. A surgical intervention was performed in the form of posterior transpedicular vertebral stabilization with titanium rods and screws. Postoperatively, relief from the lumbar region pain was reported. No neurological deficit was observed. The patient was mobilized, rehabilitated, and discharged from the hospital. This case report emphasizes the use of reliable imaging methods for the diagnosis of thoracolumbar compression fracture and highlights the reliability of surgical treatment of the condition via posterior transpedicular vertebral stabilization.

Traumatic spinal injury patterns of on vs. off-road motorcycle crashes

OBJECTIVE

Two wheel motorized vehicles used in both street transportation and recreation are a common cause of severe injury in the United States (US). To date, there has been limited data describing the spinal injury patterns among these motorcycle injury patients in the US. The goal of this study is to characterize and compare differences in specific injury patterns of patients sustaining traumatic spinal injuries after motocross (off-road) and street bike (on-road) collisions in the southwestern US at a Level I Trauma Center.

METHODS

Trauma registry data was queried for patients sustaining a spinal injury after motorcycle collision from 2010 to 2019 at a single Level I Trauma Center. Computed tomography (CT) scan and magnetic imaging resonance imaging (MRI) reports from initial trauma evaluation were reviewed and data was manually obtained regarding injury morphology and location.

RESULTS

A total of 1798 injuries were identified in 549 patients who sustained a motorcycle collision, specifically 67 off-road and 482 on-road motorcycle patients. Off-road motorcycle patients were found to be significantly younger (34.75 vs. 42.66, p = 0.00015). A total of 46.2% of the off-road injuries were determined to be from compression mechanisms, compared to 32.9% in the on-road cohort (p = 0.0027). The on-road cohort was more likely to have an injury classified as insignificant, such as transverse and spinous process fractures (60.1% vs. 42.5%, p = 00.25). There was no significant difference in regards to junctional, mobile, and semirigid spine segments between the two cohorts.

CONCLUSIONS

Different fracture patterns were seen between the off-road and on-road motorcycle cohorts. Off road motorcyclists experienced significantly more compression and translational injuries, while on road motorcyclists experienced more frequent insignificant injury patterns. Data on the different fracture patterns may help professionals develop safety equipment for motorcyclists.

Analysis of Influencing Factors of Vertebral Height Loss After Pedicle Screw Fixation of Thoracolumbar Fracture

STUDY DESIGN

Retrospective case-control study.

OBJECTIVE

To explore the related factors of vertebral height loss (VHL) after pedicle screw fixation of thoracolumbar fracture and to determine the optimum prediction point.

SUMMARY OF BACKGROUND DATA

With the widespread application of thoracolumbar fracture internal fixation, VHL after the operation is increasingly presented. However, there is no unified conclusion on the specific cause of VHL and how to predict it.

METHODS

A total of 186 patients were selected and divided into the loss group (n = 72) and the not-loss group (n = 114) according to whether the fractured vertebral height was lost after the operation. The two groups were compared concerning sex, age, body mass index, osteoporosis self-assessment tool for Asians (OSTA), fracture types, number of fractured vertebrae, preoperative Cobb angle and compression degree, number of screws, and extent of vertebral restore. Univariate analysis and Multivariate logistic regression analysis were performed to identify the independent factors for the VHL with the receiver operating characteristic curve and the optimal prediction value was calculated according to area under the curve.

RESULTS

Multivariate logistic regression analysis showed that OSTA ( P < 0.05) and preoperative vertebral compression ( P < 0.05) were significantly correlated with postoperative VHL, which were independent risk factors for postoperative VHL. The OSTA of 2.32 and the preoperative vertebral compression degree of 38.5% were the best prediction points for postoperative VHL based on the Youden Index analysis.

CONCLUSIONS

The OSTA and preoperative vertebral compression were independent risk factors for VHL. The risk of postoperative VHL was significantly higher when the OSTA was ≤2.32 or the preoperative vertebral compression was ≥38.5%.

LEVEL OF EVIDENCE

Level III.

Negative Effects of Diffuse Idiopathic Skeletal Hyperostosis on Bone Fusion after Transforaminal Lumbar Interbody Fusion

STUDY DESIGN

This study adopted a retrospective cohort study design.

PURPOSE

This study aimed to clarify the influence of diffuse idiopathic skeletal hyperostosis (DISH) on bone fusion after transforaminal lumbar interbody fusion (TLIF).

OVERVIEW OF LITERATURE

The negative effects of DISH on lumbar degenerative diseases have been reported, and DISH may be involved in the onset and severity of lumbar spinal canal stenosis. Patients with DISH have significantly more reoperations after posterior lumbar fusion, including TLIF. However, the effects of DISH on bone fusion after TLIF have not been reported.

METHODS

The medical records of patients with intervertebral TLIF from 2012 to 2018 were retrospectively examined. The patients were divided into those with fusion and those with pseudoarthrosis, and the following data were compared: age, sex, DISH, diabetes mellitus, smoking, drinking, albumin levels, body mass index ≥30 kg/m2, and L5/S fixation. Statistical analyses were performed using regression models.

RESULTS

In this study, 180 patients (78.6%) had fusion and 49 patients (21.4%) had pseudoarthrosis. The number of patients with DISH was significantly higher in the pseudoarthrosis group than in the fusion group (36.7% and 21.7%, respectively; univariate p=0.031, multivariate p =0.019). No significant differences in age, sex, diabetes mellitus, smoking, drinking, albumin levels, body mass index ≥30 kg/m2, and L5/S fixation were observed between the two groups. The risk factors for bone fusion were statistically analyzed in 57 patients with DISH. DISH with a caudal end below Th11 was an independent risk factor for pseudoarthrosis (univariate p=0.011, multivariate p=0.033).

CONCLUSIONS

DISH is an independent risk factor for pseudoarthrosis after one intervertebral TLIF, and DISH with a caudal end below Th11 is associated with a higher risk of pseudoarthrosis than DISH without a caudal end below Th11.

Thoracolumbar vertebral fracture in unoperated idiopathic scoliosis

INTRODUCTION

Traumatic fractures of the thoracolumbar spine are common. Their management considers the fracture type according to the various classifications in existence, as well as the patient's background and age. In some cases, the occurrence of a fracture on a spine with an unoperated scoliotic deformity can be observed. This entity, not described in the literature, can pose a therapeutic challenge and is not present in any existing treatment algorithm. The main objective of this work was to describe the characteristics and management of vertebral fractures in patients with unoperated idiopathic scoliosis.

MATERIAL AND METHODS

We carried out a monocentric retrospective study in all patients operated on for a spinal fracture between May 2011 and August 2020, with a history of unoperated adolescent idiopathic scoliosis. We collected epidemiological data including the surgical course of each patient and the final result. The patients were categorized according to the surgical strategy (extensive fusion and correction of the deformity, short osteosynthesis without considering the scoliosis, vertebroplasty and orthopedic treatment) and the final clinical and radiological result evaluated at the last follow-up.

RESULTS

Ten patients were included in this study with a total number of 16 fractured vertebrae. The population was 80% female, with an average age of 36.3 years. The majority of fractures were type A, at the thoracolumbar junction. The curves were classified as Lenke 1A in 5 cases, 1B in 2 cases, 1C in 1 case and 5C for 2 patients. Ultimately, 3 patients underwent extended fusion with correction of scoliosis, 6 localized osteosynthesis and 1 percutaneous vertebroplasty. In 50% of cases, a change of surgical strategy had to be made, due to worsening of the deformity or hyperalgesia. The last follow-up was at 19.7 months on average. Five patients had a good final clinical result, 5 patients had persistence of significant pain (lower back pain or cruralgia).

CONCLUSION

This is the first study investigating the association of vertebral fractures and the presence of unoperated idiopathic scoliosis. The results of our study highlight the management challenges and difficulties in therapeutic decision-making. The presence of a pre-existing curve is thus an important parameter to consider and should lead to the discussion of performing an extended fusion secondarily in view of the risk of poor results from localized surgery.

LEVEL OF EVIDENCE

IV.

Usefulness of Percutaneous Pedicle Screw Fixation for Treatment of Lower Lumbar Burst (A3-A4) Fractures: Comparative Study with Thoracolumbar Junction Fractures

Background

Percutaneous pedicle screw fixation (PPSF) without fusion has been recently recommended in the treatment of thoracolumbar fracture to reduce the adverse effects associated with the conventional open approaches and to restore range of motion. However, those studies report on the thoracolumbar junction, and there is no report on lower lumbar fracture.

Purpose

To assess effectiveness of PPSF without fusion for treating lower lumbar burst (A3 and A4) fractures.

Methods

A retrospective analysis was made to evaluate consecutive 50 patients with AO type A3 and A4 thoracolumbar fracture underwent PPSF. Patients were divided into a thoracolumbar junction (TLJ) group (T11-L2) and lower lumbar (LL) group (L3-5). The following items were measured and compared between the two groups. Vertebral height and consolidation, retropulsed fragment, sagittal curve and fixation failure were assessed with certain interval regularly.

Results

The average height at pre- and post-reduction were 56.2% (36.2-74.3), 95.3% (84.2-98.3) in TLJ group and 65.7% (45.7-86.2), 91% (73.1-100) in LL group. The average canal area occupancy rate at pre- and post-reduction were 46.1% (37.4%-67.5%), 38.1% (31.3%-40.8%) in TLJ group and 40.4% (15.0-65.7), 19.3% (9.4-26.6) in LL group. Consolidation was completed within 12 months after surgery in both groups. There was no significant difference between two groups in clinical and radiographic parameters except cobb angle loss.

Conclusion

Patients with lower lumbar fracture can be effectively managed with PPSF without fusion. PPSF following the implant removal can restore the movement of the lower lumbar spine, which is essential for daily life.

Clinic choice of long or short segment pedicle screw-rod fixation in the treatment of thoracolumbar burst fracture: From scan data to numerical study

Based on computerized tomography scanning images of human lumbar vertebrae, finite element (FE) analysis is performed to predict the stress of pedicle screws, rods, and fractured vertebra as well as the displacement of fractured vertebra after internal fixation treatment of thoracolumbar burst fracture. A three-dimensional FE model of L1-L5 lumbar vertebrae with L3 burst fracture has been established and four fixation methods, namely, short segment cross- and trans-injured vertebrae, long segment cross- and trans-injured vertebrae fixations, have been adopted to perform posterior pedicle fixation. The stress distributions of the screws, rods, and fractured vertebra and the total deformation of the fractured vertebra are investigated under six different physiological motions. From the view of the stress on the screw-rod system and the deformation of the fractured vertebral body, the long segment cross-injured vertebra fixation has the best mechanical performance, followed by the long segment trans-injured vertebra fixation, and then the short segment fixation trans-injured vertebra. The short segment fixation cross-injured vertebra performs the worst. Among the six motions, the forward flexion movement has the greatest impact on the screw-rod system and the fractured vertebra. However, the rotation motion greatly affects the stress of the screw in the long segment fixation. This indicates that the longer the fixed segment is, the more susceptible it is to human rotation. Thus, for patients with severe fracture, the long segment cross-injured vertebra is preferred. On the contrary, the short segment trans-injured vertebra fixation is optimal.

Effects of Bone Cross-Link Bridging on Fracture Mechanism and Surgical Outcomes in Elderly Patients with Spine Fractures

STUDY DESIGN

This study adopted a cross-sectional study design.

PURPOSE

This study was designed to investigate the effects of bone cross-link bridging on fracture mechanism and surgical outcomes in vertebral fractures using the maximum number of vertebral bodies with bony bridges between adjacent vertebrae without interruption (maxVB).

OVERVIEW OF LITERATURE

The complex interplay of bone density and bone bridging in the elderly can complicate vertebral fractures, necessitating a better understanding of fracture mechanics.

METHODS

We examined 242 patients (age >60 years) who underwent surgery for thoracic to lumbar spine fractures from 2010 to 2020. Subsequently, the maxVB was classified into three groups: maxVB (0), maxVB (2-8), and maxVB (9-18), and parameters, including fracture morphology (new Association of Osteosynthesis classification), fracture level, and neurological deficits were compared. In a sub-analysis, 146 patients with thoracolumbar spine fractures were classified into the three aforementioned groups based on the maxVB and compared to determine the optimal operative technique and evaluate surgical outcomes.

RESULTS

Regarding the fracture morphology, the maxVB (0) group had more A3 and A4 fractures, whereas the maxVB (2-8) group had less A4 and more B1 and B2 fractures. The maxVB (9-18) group exhibited an increased frequency of B3 and C fractures. Regarding the fracture level, the maxVB (0) group tended to have more fractures in the thoracolumbar transition region. Furthermore, the maxVB (2-8) group had a higher fracture frequency in the lumbar spine area, whereas the maxVB (9-18) group had a higher fracture frequency in the thoracic spine area than the maxVB (0) group. The maxVB (9-18) group had fewer preoperative neurological deficits but a higher reoperation rate and postoperative mortality than the other groups.

CONCLUSIONS

The maxVB was identified as a factor influencing fracture level, fracture type, and preoperative neurological deficits. Thus, understanding the maxVB could help elucidate fracture mechanics and assist in perioperative patient management.

Posterior unilateral small fenestration of lamina combined with a custom-made Y-shaped fracture reduction device for the treatment of severe thoracolumbar burst fracture: a prospective comparative study

BACKGROUND

The purpose was to evaluate the clinical effect of a custom-made Y-shaped fracture fragment reduction device and to assist in posterior unilateral small fenestration of lamina to reduce the fracture fragments.

METHODS

In this study, 40 patients were assigned to one of two groups: the traditional reduction device group (TRG) or the Y-shaped reduction device group (YRG). All patients underwent posterior unilateral small fenestration of the lamina and direct decompression through the spinal canal. And the operation time (OT), intraoperative bleeding (IB), preoperative, postoperative, and final follow-up data on the spinal stenosis rate (SSR), Cobb angle, the anterior compression ratio of injured vertebrae (ACRIV), and ASIA neurological function grade were compared between the two groups.

RESULT

There were no complications, including vascular and nerve injury, serious postoperative infection, internal fixation fracture, or loosening, for any of the patients. And the average follow-up time of the two groups was 14.2 months, the average operation time of the TRG was 236.6 min, and the average intraoperative blood loss was 357.20 ml. Moreover, the average operation time of the YRG was 190.6 min, and the average intraoperative blood loss was 241.5 ml. There were significant differences between the two groups in terms of operation duration and intraoperative blood loss. The YRG's was lower than that of the TRG. Besides, there was no difference in SSR, Cobb angle, ACRIV, or neurological recovery between the two groups before or immediately after the operation or at the last follow-up.

CONCLUSION

The Y-shaped fracture reduction device can reduce the fracture fragments and the OT and IB stably; it also has satisfactory postoperative curative effects and clinical utility.

Finite element analysis of minimally invasive nail placement and traditional nail placement in the treatment of lumbar 1 vertebral compression fracture

Using the finite element analysis method to help us better understand the biomechanical changes of the spine after surgery and the changes in the stress distribution around the screw implantation area. The finite element model of L1 vertebral compression fracture was constructed by using a large number of finite element programs. On the fracture model, 2 kinds of internal fixation devices are set up, namely: the first type of 4 screws across the injured vertebra through the adjacent upper and lower vertebrae + transverse connector; the second type of 4 screws crosses the injured vertebra through the adjacent upper and lower vertebrae + non-transverse connector. To study the distribution of the maximum displacement and von Mises stress of the intramedullary pedicle screws and rods of the 2 types of internal fixation devices after implantation in the spine under certain loading conditions. In traditional open pedicle screw fixation, the maximum stress in the pedicle screw fixation system in the direction of 3D movement is higher than in percutaneous pedicle screw fixation. There is no significant difference in the Von Mises stress of the pedicle screw between the 2 procedures when the spine performs flexion-extension and lateral flexion activities. When the spine is rotating axially, the Von Mises stress of the pedicle screw in conventional open surgery is significantly less than that of the screw in percutaneous pedicle screw fixation. Traditional open internal fixation produces stress peaks of 891.7 MPa and 886.34 MPa at the transverse joint during axial rotation. Only when the spine is rotating in the axial direction, the maximum displacement of traditional open pedicle screw fixation is smaller than that of percutaneous pedicle screw fixation. There is no significant difference in the maximum displacement between the 2 procedures when the spine is moving in other directions. Traditional open pedicle screw fixation can strengthen the stability of the spine in the direction of axial rotation, and can also be greater to reduce the maximum stress of the pedicle screw axial rotation, so the clinical treatment of unstable fractures of the thoracolumbar spine instability is of great significance.

Correlation analysis of the vertebral compression degree and CT HU value in elderly patients with osteoporotic thoracolumbar fractures

BACKGROUND

To explore the correlation of the vertebral compression degree and cancellous bone CT HU in elderly patients with osteoporotic thoracolumbar fractures.

METHODS

Elderly patients with single-segment vertebral fragility fractures were retrospectively reviewed. All patients experienced a low-energy trauma and underwent thoracolumbar MRI. The consistency of measurement between two spine surgeons was evaluated. The average CT HU value of the adjacent vertebral body was used instead.

RESULTS

A total of 54 patients were included in the final analysis. The patients' average age was 70.39 ± 8.53 years, and the average CT HU value was 72.78 ± 29.75 HU. The average vertebral compression ratio was 0.57 ± 0.16. Measurements showed both good intrarater repeatability and good interrater reproducibility of the vertebral compression ratio (ICC = 0.978). The degree of vertebral compression in thoracolumbar osteoporotic fractures was strongly positively correlated with the cancellous bone CT HU value (P < 0.01).

CONCLUSIONS

The local bone quality as evaluated by the CT HU value is an important factor affecting the degree of compression in osteoporotic vertebral fractures. This study provides quantitative evidence that a greater compression ratio with thoracolumbar osteoporotic fractures was associated with lower bone density in elderly patients. Further longitudinal studies with larger cohorts are needed to verify this relationship.

A practical method for the retrieval of tulip-head polyaxial pedicle screw by reusing the rod in revision and implants removal surgery: introduction of technique and evaluation of clinical outcomes

BACKGROUND

The removal of spinal implants is needed in revision surgery or in some cases whose fracture had healed or fusion had occurred. The slip of polyaxial screw or mismatch of instruments would make this simple procedure intractable. Here we introduce a simple and practical method to address this clinical dilemma.

METHODS

This is a retrospective study. The patients underwent new technique for retrieving the implants from July 2019 to July 2022 were labeled as group A, while the patients underwent traditional implants retrieval technique from January 2017 to January 2020 were labeled as group B. Patients in each group were subdivided into revision surgery group (r group) and simple implants removal group (s group) according to the surgery fashion. For the new technique, the retrieved rod was cut off to a proper length which was matched with the size of tulip head, and was replaced into the tulip head. After tightened with nut, a monoaxial screw-rod "construct" was formed. Then the "construct" can be retrieved by a counter torque. The operation duration, intraoperative blood loss, post-operative bacteria culture, hospital stay and costs were analyzed.

RESULTS

A total of 116 polyaxial screws with difficult retrieval (43 screws in group A, 73 screws in group B) in 78 patients were recorded, in which 115 screws were successfully retrieved. Significant differences were found in the mean operation duration, intraoperative blood loss when comparing the r group in group A and B, as well as the s group in group A and B (P < 0.05). There were no significant differences in hospital stay and costs between group A and B. Three patients were found positive bacteria culture of drainage tube/tape in group A (3/30), while 7 patients in group B (7/48). The most prevalent bacteria was Propionibacterium acnes.

CONCLUSION

This technique is practical and safe in retrieving tulip head poly-axial screw. Reduced operation duration and intraoperative bloods loss may potentially alleviate the hospitalization burden of patients. Positive bacterial cultivation results are common after implants removal surgery, but they rarely represent an organized infection. A positive culture with P. acnes or S. epidermidis should be interpreted with caution.

Injury patterns of the spine following blunt trauma: A per-segment analysis of spinal structures and their detection rates in CT and MRI

Rationale and objectives

To provide a detailed analysis of injury patterns of the spine following blunt trauma and establish the role of supplementary MRI by evaluating discrepancies in the detection rates of damaged structures in CT and MRI.

Method

216 patients with blunt trauma to the spine who underwent CT followed by supplementary MRI were included in this study. Two board-certified radiologists blinded to clinical symptoms and injury mechanisms independently interpreted all acquired CT and MRI images. The interpretation was performed using a dedicated catalogue of typical findings associated with spinal trauma and assessed for spinal stability using the AO classification systems.

Results

Lesions to structures associated with spinal instability were present in 31.0% in the cervical spine, 12.3% in the thoracic spine, and 29.9% in the lumbar spine. In all spinal segments, MRI provided additional information regarding potentially unstable injuries. Novel information derived from supplementary MRI changed clinical management in 3.6% of patients with injury to the cervical spine. No change in clinical management resulted from novel information on the thoracolumbar spine. Patients with injuries to the vertebral body, intervertebral disc, or spinous process were significantly more likely to benefit from supplementary MRI.

Conclusion

In patients that sustained blunt spinal trauma, supplementary MRI of the cervical spine should routinely be performed to detect injuries that require surgical treatment, whereas CT is the superior imaging modality for the detection of unstable injuries in the thoracolumbar spine.

Long segment versus short segment stabilization in thoracolumbar spine fracture: A retrospective clinical and radiological analysis

Introduction: Thoracolumbar spine fracture is one of the commonest spinal fractures. The treatment of choice of surgery is still controversial. This is a retrospective analysis of clinical and radiological outcomes of long and short segment stabilization for patients admitted with thoracolumbar fracture in our hospitals. Material and Method: Inclusion criteria included a single level of thoracolumbar fracture, excluding pre-existing deformity or spinal surgery, osteoporosis, and pathological fracture. Clinical parameters included visual analogue scale (VAS), operative time, intraoperative blood loss, and postoperative length of stay. Radiological parameters included wedge angle and anterior and posterior vertebral height ratio. Results: From June 2007 to May 2020, 56 patients (male = 31, female = 25) were recruited. There were 25 patients in the short segment group (open = 11, minimal invasive surgery (MIS) = 14) and 31 patients in the long segment group. Clinically, significantly better VAS at 6 months (1 vs. 1.96; p = 0.041), shorter post-op length of stay (16 days vs. 25 days; p = 0.01), and less blood loss (178 ml vs. 824 ml; p < 0.01) were found in the short segment group. Radiologically, the short segment group showed significantly better wedge angle at immediate (5° vs. 9.23°; p = 0.002) and long-term follow-up (7.41° vs. 11.43°; p = 0.01). Moreover, the short segment group has significantly better post-op anterior and posterior vertebral height ratios. Within the short segment group, the MIS group showed significantly less blood loss (82 ml vs. 303 ml; p < 0.01). However radiological parameters favour the open group. Discussion and Conclusion: For single-level thoracolumbar fracture, both long and short stabilizations were effective in reducing and stabilizing the fracture. However, the short segment group showed significantly superior results. Moreover, a minimally invasive technique in short segment stabilization showed even less blood loss but less optimal radiological results. Therefore, short segment stabilization could be the treatment of choice for traumatic thoracolumbar spine fractures.