Biomechanical analysis of the tandem spinal external fixation in a multiple-level noncontiguous lumbar fractures model: a finite element analysis.

Objective: This study aimed to investigate the biomechanical characteristics of the tandem spinal external fixation (TSEF) for treating multilevel noncontiguous spinal fracture (MNSF) using finite element analysis and provide a theoretical basis for clinical application. Methods: We constructed two models of L2 and L4 vertebral fractures that were fixed with the TSEF and the long-segment spinal inner fixation (LSIF). The range of motion (ROM), maximum stresses at L2 and L4 vertebrae, the screws and rods, and the intervertebral discs of the two models were recorded under load control. Subsequently, the required torque, the maximum stress at L2 and L4 vertebrae, the screws and rods, and the intervertebral discs were analyzed under displacement control. Results: Under load control, the TSEF model reserved more ROM than the LSIF model. The maximum stresses of screws in the TSEF model were increased, while the maximum stresses of rods were reduced compared to the LSIF model. Moreover, the maximum stresses of L2 and L4 vertebrae and discs in the TSEF model were increased compared to the LSIF model. Under displacement control, the TSEF model required fewer moments (N·mm) than the LSIF model. Compared to the LSIF model, the maximum stresses of screws and rods in the TSEF model have decreased; the maximum stresses at L2 and L4 in the TSEF model were increased. In the flexion condition, the maximum stresses of discs in the TSEF model were less than the LSIF model, while the maximum stresses of discs in the TSEF model were higher in the extension condition. Conclusion: Compared to LSIF, the TSEF has a better stress distribution with higher overall mobility. Theoretically, it reduces the stress concentration of the connecting rods and the stress shielding of the fractured vertebral bodies.

Can conservative treatment be effective for thoracolumbar injuries patients with TLICS scores of 4 or 5? An analysis of initial radiological findings and clinical risk factors for treatment failure.

BACKGROUND: This study aimed to assess the outcomes of conservative management in patients with thoracolumbar fractures classified with a Thoracolumbar Injury Classification and Severity (TLICS) score of 4 or 5, and to analyze initial imaging findings and clinical risk factors associated with treatment failure. METHODS: In this retrospective analysis, patients with thoracolumbar fractures and a TLICS score of 4 or 5, determined through MRI from January 2017 to December 2020, were included. Patients undergoing conservative treatment were categorized into two groups: Group 1 (treatment success) and Group 2 (treatment failure), based on initial and 6-month follow-up outcomes. Clinical data were compared between the two groups. Initial radiological assessments included three kyphosis measurements (Cobb angle, Gardner angle, and sagittal index [SI]), anterior and posterior wall height, and central canal compromise (CC). Additionally, risk factors contributing to treatment failure were analyzed. RESULTS: The conservative treatment group comprised 84 patients (mean age, 60.25 ± 15.53; range 22-85; 42 men), with 57 in Group 1 and 27 in Group 2. Group 2 exhibited a higher proportion of women, older age, and lower bone mass density (p = 0.001-0.005). Initial imaging findings in Group 2 revealed significantly greater values for Cobb angle, SI, and CC (p = 0.001-0.045 or < 0.001; with cutoff values of 18.2, 12.8, and 7.8%, respectively), and lower anterior wall height (p = 0.001), demonstrating good to excellent interobserver agreement (0.72-0.99, p < 0.001). Furthermore, osteoporosis was identified as a significant risk factor (odds ratio = 5.64, p = 0.008). CONCLUSION: Among patients with TLICS scores of 4 or 5, those experiencing conservative treatment failure exhibited unfavorable initial radiological findings, a higher proportion of women, advanced age, and osteoporosis. Additionally, osteoporosis emerged as a significant risk factor for treatment failure.

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.

Racial Disparities in Outcomes Following Surgical Fixation of Traumatic Thoracolumbar Fractures: A National Database Analysis.

OBJECTIVE: This study aims to assess race as an independent risk factor for postoperative complications after surgical fixation of traumatic thoracolumbar fractures for African American and Asian American patients compared with White patients. 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. Patient comorbidity burden was assessed using a modified 5-item frailty index score (mFI-5). Chi-squared and ANOVA tests were used to compare baseline clinical characteristics between groups. Multivariate analysis was performed to compare African American and Asian American patients with White patients controlling for age, BMI, and American Society of Anesthesiologists (ASA) score. RESULTS: African American patients experienced longer operative times compared to Asian American and White patients (3.74 ± 1.87 hours vs. 3.04 ± 1.71 hours and 3.48 ± 1.81 hours, P < 0.001). African American and Asian American patients demonstrated higher comorbidity burden with mFI-5>2 compared to White patients (30.7% and 25.6% vs. 19.9%, P < 0.001). African American and Asian American patients had a higher risk of postoperative complications than White patients (22.4% and 20% vs. 19.7%, P < 0.001). African American race was an independent risk factor of postoperative 30-day morbidity (OR 1.19, CI 1.11-1.28, P < 0.001). CONCLUSIONS: African American and Asian American patients undergoing thoracolumbar fusion surgeries exhibit disproportionate comorbidity burden, longer LOS, and greater postoperative complications compared with White patients. Furthermore, the African American race was associated with an increased rate of 30-day postoperative complications.

Accuracy of mapping results of thoracolumbar vertebral fracture verified using finite element analysis.

OBJECTIVE: To verify the results of three-dimensional fracture mapping of T12-L2 compression fractures by the finite element method from a biomechanical point of view, and to provide clinical reference. METHODS: This study is a retrospective study. By collecting 150 patients' computerized tomography (CT) data with thoracolumbar compression fractures (T12-L2) with AO type A. Mimics was used for three-dimensional (3D) reconstruction, and 3-Matic was used to mark fracture lines in stereo images. After standardized treatment, all fracture lines were drawn in the same 3D image, and finally fracture lines and fracture map were drawn. Constructing a 3D finite element model of thoracolumbar segment to verify the fracture thermogram results from the perspective of biomechanics. RESULTS: From the fracture map, fracture lines were mainly distributed in the upper part of the vertebral body, the leading edge of the anterior column (AC), and the lateral margin of the middle column (MC). In the finite element analysis, the stress mainly was concentrated on the edge of the anterior and middle column of the vertebral body and the upper part of the vertebral body, and the stress gradually decreased from the upper endplate to the endplate, and the stress was the least in the posterior column (PC) of the vertebral body. CONCLUSION: The results of finite element analysis further confirm the accuracy of fracture mapping and explain the distribution characteristics of fracture lines. This will provide theoretical support for the selection of clinical fracture treatment, intraoperative implants, and for a standard fracture model.

Fractured vertebra antedisplacement reconstruction technique: a feasible treatment choice for posttraumatic thoracolumbar kyphosis.

OBJECTIVE: The goal of this study was to evaluate the feasibility of the fractured vertebra antedisplacement reconstruction technique for the treatment of posttraumatic thoracolumbar kyphosis (PTK). METHODS: A total of 22 patients with PTK who were treated with the fractured vertebra antedisplacement reconstruction technique were retrospectively analyzed. The radiological evaluation included global kyphosis, thoracolumbar angle, and sagittal vertical axis. The clinical evaluation included visual analog scale pain score, Oswestry Disability Index score, SF-12 Health Survey score, and American Spinal Injury Association grade. The complications were recorded. RESULTS: The mean global kyphosis was 55.0° ± 12.6° preoperatively, 8.5° ± 5.0° postoperatively, and 10.3° ± 4.8° at the latest follow-up (p < 0.001). The average total kyphosis correction achieved was 44.7° ± 14.2°, with a range of 23.4°-79.4°, indicating a mean final correction of 80.1%. The mean thoracolumbar angle was 46.2° ± 13.2° preoperatively, 6.6° ± 4.5° postoperatively, and 7.6° ± 4.2° at the latest follow-up (p < 0.001). The mean sagittal vertical axis was improved significantly, from 51.1 ± 24.2 mm preoperatively to 28.5 ± 17.4 mm at the latest follow-up (p = 0.001). One patient (4.5%) experienced single intervertebral fusion nonunion, and 1 patient (4.5%) experienced distal screw loosening. No patients experienced any neurological deterioration. The visual analog scale pain score, Oswestry Disability Index score, SF-12 Health Survey score, and American Spinal Injury Association grade achieved significant improvement at the latest follow-up. CONCLUSIONS: Fractured vertebra antedisplacement reconstruction technique can effectively correct kyphosis, reconstruct spinal stability, and improve the patient's symptoms and neurological function. This technique is safer, minimally traumatic, and less technically demanding to avoid osteotomy-related complications. It is a feasible treatment choice for PTK.

Thoracolumbar fractures patients undergoing posterior pedicle screw fixation can benefit from drainage.

PURPOSE: To explore whether it is necessary to put drain tubes after posterior pedicle screw fixation of thoracolumbar fractures. METHODS: From April 2020 to January 2023, a total of 291 patients with recent thoracolumbar fractures (AO type-A or type-B) who received the pedicle screw fixation operation were enrolled retrospectively. In 77 patients, drain tubes were used in the pedicle screw fixation surgery, while no drain tubes were placed in the other group. After gleaning demographic information and results of lab examination and imageology examination, all data were put into a database. Independent-sample t-tests, Pearson Chi-Square tests, Linear regression analysis, and correlation analysis were then performed. RESULTS: Compared to the control group, the drainage group had significantly lower postoperative CRP levels (P = 0.047), less use of antipyretics (P = 0.035), higher ADL scores (P = 0.001), and lower NRS scores (P < 0.001) on the 6th day after surgery. Other investigation items, such as demographic information, operation time, intraoperative blood loss, body temperature, and other preoperative and postoperative lab results, showed no significant differences. CONCLUSIONS: The use of a drain tube in the pedicle screw fixation of thoracolumbar fractures is correlated with the improvement of patients' living and activity ability and the reduction of inflammation, postoperative fever and pain.

Percutaneous reduction of thoracolumbar fractures using monoaxial screws: Comparison of two instruments based on initial reduction and loss of reduction.

Introduction: Percutaneous techniques for the surgical treatment of vertebral fractures are constantly progressing. There are different biomechanics involved. Research question: Two percutaneous, monoaxial fixation systems with different reduction tools were analyzed in relation to their reduction capacity. Additionally, the impact of anterior fusion, fracture severity and bone quality on reduction and loss of reduction were examined. Material and methods: 117 cases were retrospectively included in the monocentric study. The subsample (N = 53) with complete data at follow-up times was used to analyze the influence of anterior fusion. The dependencies on fracture severity and bone quality were determined using Spearman and Pearson correlation. Results: Both systems achieved equally good reduction (9° mean, 95%-CI: 8°-11°, p < 0.001). Anterior fused patients showed not significant (p = 0.057) less loss of reduction over time. Fracture severity had neither an influence on reduction or loss of reduction. Bone quality was positively correlated with greater amount of reduction and less loss of reduction. Early reduction within two days correlated with a greater amount of reduction (p = 0.006). Screw diameters and the patient's weight had no influence on loss of reduction. Complications occurred only in "V2" group. Discussion and conclusion: Both systems are equivalent in reduction ability. The additional anterior fusion did not result in significantly lower reduction losses. The subsample being small, is a limitation. Good bone quality correlates with better initial reduction and less reduction loss. A preoperative bone density measurement can lead to optimization of surgical techniques.

[Effectiveness of injured vertebra fixation with inclined-long pedicle screws combined with interbody fusion for thoracolumbar fracture dislocation with disc injury].

Objective: To investigate the effectiveness of injured vertebra fixation with inclined-long pedicle screws combined with interbody fusion for thoracolumbar fracture dislocation with disc injury. Methods: Between January 2017 and June 2022, 28 patients with thoracolumbar fracture dislocation with disc injury were underwent posterior depression, the injured vertebra fixation with inclined-long pedicle screws, and interbody fusion. There were 22 males and 6 females, with a mean age of 41.4 years (range, 22-58 years). The causes of injury included falling from height in 18 cases, traffic accident in 5 cases, and bruise in 5 cases. Fracture segment included 1 case of T 11, 7 cases of T 12, 9 cases of L 1, and 11 cases of L 2. According to the American Spinal Injury Association (ASIA) scale, the spinal injuries were graded as grade A in 4 cases, grade B in 2 cases, grade C in 11 cases, and grade D in 11 cases. Preoperative spinal canal encroachment ratio was 17.7%-75.3% (mean, 44.0%); the thoracolumbar injury classification and severity score (TLICS) ranged from 9 to 10 (mean, 9.9). Seventeen patients were associated with other injuries. The time from injury to operation ranged from 1 to 4 days (mean, 2.3 days). The perioperative indicators (operation time, intraoperative blood loss, and the occurrence of complications), clinical evaluation indicators [visual analogue scale (VAS) score and Oswestry Disability Index (ODI)], radiologic evaluation indicators [anterior vertebral height ratio (AVHR), kyphosis Cobb angle (KCA), intervertebral space height (ISH), vertebral wedge angle (VWA), displacement angle (DA), and percent fracture dislocation displacement (PFDD)], neurological function, and interbody fusion were recorded. Results: The operation time was 110-159 minutes (mean, 130.2 minutes). The intraoperative blood loss was 200-510 mL (mean, 354.3 mL). All incisions healed by first intention, and no surgical complications such as wound infection or hematoma occurred. All patients were followed up 12-15 months (mean, 12.7 months). The chest and lumbar pain significantly relieved, VAS scores and ODI after operation were significantly lower than those before operation, and further decreased with the extension of postoperative time, with significant differences ( P<0.05). At last follow-up, the ASIA classification of neurological function of the patients was grade A in 3 cases, grade B in 1 case, grade C in 1 case, grade D in 10 cases, and grade E in 13 cases, which was significantly different from preoperative one ( Z=-4.772, P<0.001). Imaging review showed that AVHR, KCA, ISH, VWA, DA, and PFDD significantly improved at 1 week, 3 months and last follow-up ( P<0.05). There was no significant difference between different time points after operation ( P>0.05). At last follow-up, according to the modified Brantigan score, all patients achieved good intervertebral bone fusion, including 22 complete fusion and 6 good intervertebral fusion with a few clear lines. No complications such as internal fixation failure or kyphosis occurred during follow-up. Conclusion: The injured vertebra fixation with inclined-long pedicle screws combined with interbody fusion is an effective treatment for thoracolumbar fracture dislocation with disc injury, which can correct the fracture dislocation, release the nerve compression, restore the injured vertebral height, and reconstruct spinal stabilization.

Is open anterior advantageous to posterior decompression and reconstruction in fresh A3 to C3/AO type thoracolumbar junction fractures? A systematic review.

INTRODUCTION: Surgical outcomes of open anterior and open posterior approaches, for thoracolumbar A3 to C3/AO type fractures, are compared. METHODS: A PubMed search was conducted from 1990 to 2024 related to anterior, posterior, and combined approaches. Inclusion criteria: Fresh traumatic T10 to L2 fractures, age ≥13 years, ≥10 cases, minimum follow-up 6 months. Exclusion criteria: Cadaveric studies, pathological fractures, reviews, thoracoscopy-assisted, mini-open lateral (MOLA) and minimal invasive anterior or posterior approaches. Coleman Methodology Scores (CMS) (modified for spinal trauma) indicated potential selection bias in the selected studies. PRISMA guidelines were adapted. RESULTS: Nineteen studies with 847 participants were selected. The average CMS quality score was fair. The anterior approach, although it better decompresses the compromised spinal canal, it is also associated with increased surgical complications compared to the posterior approach. The neurological outcome, the loss of correction and the reoperation rate, were similar to both approaches. This systematic review favors posterior approach. CONCLUSIONS: The anterior approach is demanding and is associated with a higher rate of surgical complications compared to the posterior approach. The limitations of the selected studies included inconsistence in the: 1) approaches selection, 2) classifications of the fracture types and the neurological status and 3) variety of instrumentations used. PROSPERO ID: CRD42023484222.

Surgeon reported treatment choices for AO type B and C thoracolumbar fractures without neurological deficits: An expert survey.

INTRODUCTION: Less invasive spine surgery (LISS) has become well-established for thoracolumbar burst fractures without neurological deficits. However, notable controversy persists regarding the adequacy of LISS for more unstable AO type B and C injuries, as it does not allow for formal open fusion. MATERIALS AND METHODS: In this cross-sectional survey experienced spine surgeons of the Dutch Spine Society were invited to participate (56 participants). They were asked to indicate the most appropriate treatment for AO type B1, B2 (L1: A1 and L1: A3), B3 and C (L1: A4) injuries at level Th12-L1. Taking into account: age, AO N0-N1, or polytrauma. Specific agreement between participants was obtained applying Variation Ratio (VR). RESULTS: A significant level of overall agreement was observed for AO type-B1 injuries with 73.8% of participants opting for percutaneous short-segment fixation (VR 0.775). For AO type-B3 injuries, 79.4% of participants favored percutaneous long-segment fixation (VR 0.794). for AO type-B2 injuries, there was less overall agreement (VR 0.571-0.657). Nonetheless, when considering all AO type-B injuries combined, percutaneous fixation emerged as the most preferred treatment option with substantial agreement (VR 0.871-0.923). Conversely, for AO type-C injuries, there was less agreement among the participants (VI 0.411), 26.5% of them chose additional open spinal fusion. CONCLUSION: For all AO type-B injuries there was substantial agreement to treat these fractures with percutaneous techniques. For AO type-C injuries, the survey results do not support a consensus. Nevertheless, the responses raise important questions about the necessity of spinal fusion for such injuries.

Multidisciplinary and Coordinated Management of Osteoporotic Vertebral Compression Fractures: Current State of the Art.

Osteoporotic vertebral compression fractures (OVCFs) present a significant health concern, affecting a substantial portion of the older adult population worldwide. This narrative review explores the prevalence, diagnostic challenges and management strategies for OVCFs. Despite the increasing incidence and impact on morbidity and mortality, existing clinical guidelines lack consistency and clear diagnostic and therapeutic recommendations. The review addresses key questions faced by physicians dealing with older adult patients experiencing acute back pain, offering insights into triage, radiological assessments and classification systems. We propose a comprehensive algorithm for clearing OVCF, considering clinical presentation, radiological findings and morphological aspects. Emphasis is placed on the importance of medically treating osteoporosis alongside OVCF management. The review encompasses relevant literature from 1993 to 2023, provides a detailed discussion on triage issues and incorporates a clinically oriented classification system developed by the German Society for Orthopaedics and Trauma. The Material and Methods section outlines the extensive literature search carried out in PUBMED, encompassing clinical and experimental studies, systematic reviews and meta-analyses. The articles retained focused mainly on answering critical questions regarding radiological assessments, imaging modalities and the presence of a specific classification system for OVCFs. The review emphasises that the evaluation and management of OVCFs necessitates a multidisciplinary approach involving spine specialists and bone disease experts. It also addresses the role of conservative versus surgical treatments, with a focus on percutaneous vertebral augmentation. The conclusion summarises the algorithm derived for use in emergency departments and general practice, aiming to streamline OVCF management, reduce unnecessary examinations and ensure optimal patient care. The algorithm recommends primary diagnosis using computed tomography, with magnetic resonance imaging reserved for specific cases. The review advocates a holistic approach, integrating medical and surgical interventions to address the complex challenges posed by OVCFs in ageing populations.

Analysis of factors influencing the intravertebral shell phenomenon after posterior reduction internal fixation of thoracolumbar fracture: a retrospective study.

STUDY DESIGN: A retrospective study. PURPOSE: The study objectives were as follows: 1) to analyze the factors influencing the occurrence of the intravertebral shell phenomenon (ISP) after thoracolumbar spinal fracture surgery and the evolutionary outcome of this phenomenon; and 2) to make recommendations for the clinical prevention and treatment of ISP. METHODS: We retrospectively analyzed 331 patients with single-segment fractures of the thoracolumbar spine treated with internal fixation via a pedicle screw-rod system. Univariate and multivariate logistic regression were used to analyze factors influencing ISP. RESULTS: A total of 260 patients (78.5%) developed ISP after surgery. Reduced bone mineral density, screw insertion depth, degree of vertebral body injury, and excessive vertebral body spreading were significantly associated with the occurrence of ISP (P < 0.05). A total of 166 of the 260 patients were reviewed via CT at 1 year postoperatively. Among them, 104 patients (62.6%) showed shrinkage or healed vertebral cavities, and 62 patients (37.4%) showed enlarged vertebral cavities or collapsed endplates. CONCLUSION: In clinical management, surgeons need to focus on risk factors for ISP, which include decreased bone density, preoperative vertebral overcompression, intraoperative vertebral overextension, screw insertion depth, and the degree of vertebral repositioning. At the 1-year postoperative follow-up, some of the vertebrae with ISP failed to heal or even showed vertebral cleft enlargement, which would affect the stability of the internal fracture fixation device and the quality of the patient's daily life.

Straight Leg Raise Cannot Replace Computed Tomography in the Detection of Spinal Column Fractures.

INTRODUCTION: An active straight leg raise (SLR) is a weight bearing test which assesses pain upon movement and a patient's ability to load their pelvis, lumbar, and thoracic spine. Since many stable patients undergo computed tomography (CT) scanning solely for spinal tenderness, our hypothesis is that performing active straight leg raising could effectively rule out lumbar and thoracic vertebral fractures. METHODS: Blunt trauma patients ≥18 years of age with Glasgow Coma Scale 15 presenting in hemodynamically stable condition were screened. Patients remaining in the supine position were asked to perform SLR at 12, 18, and 24 inches above the bed. The patient's ability to raise the leg, baseline pain, and pain at each level were assessed. Patients also underwent standard CT scanning of the chest, abdomen and pelvis. The clinical examination results were then matched post hoc with the official radiology reports. RESULTS: 99 patients were screened, 65 males and 34 females. Spinal fractures were present in 15/99 patients (16%). Mechanisms of injury included motor vehicle collision 51%, pedestrian struck 25%, fall1 9%, and other 4%. The median pain score of patients with and without significant spinal fractures at 12, 18, 24 inches was 7.5, 7, 6 and 5, 5, 4, respectively. At 24 inches, active SLR had sensitivity of 0.47, a specificity of 0.59, a positive predictive value of 0.17, and an negative predictive value of 0.86. CONCLUSIONS: Although SLR has been discussed as a useful adjunct to secondary survey and physical exam following blunt trauma, its positive and more importantly negative predictive value are insufficient to rule out spinal column fractures. Liberal indications for CT based upon mechanism and especially pain and tenderness are necessary to identify all thoraco-lumbar spine fractures.

Factors Associated with Intradiscal Vacuum Phenomenon after Traumatic Thoracolumbar Fracture.

Introduction Posttraumatic kyphosis of the thoracolumbar spine is a possible cause of deterioration of activities of daily living. Thus, postoperative kyphosis is an important issue in treating traumatic thoracolumbar fractures. The intradiscal vacuum phenomenon (IVP) after a traumatic thoracolumbar fracture is considered an important predictor of severe kyphosis after implant removal. However, the associated factors are not yet clear. Methods The study included data from 94 intervertebral discs on the cephalocaudal side of 47 fractured vertebrae of 45 patients for traumatic thoracolumbar fracture due to high-energy trauma. We assessed the demographics of patients (age, sex, cause of injury, location of injured vertebra, fracture type, cephalocaudal side), imaging finding (kyphosis angle of fractured vertebra at the injury, endplate fracture on computed tomography [CT], intervertebral injury on magnetic resonance image [MRI]), and IVP on CT conducted more than 6 months after surgery. We divided the intervertebral discs into an IVP group and a non-IVP group. To identify factors associated with an IVP, univariate analysis and multivariate logistic regression analysis were conducted. Results IVP was observed in 27 (29%) of 94 intervertebral discs on CTs conducted at an average of 14.0 months postoperatively. In univariate analysis, the IVP group ( n = 27) had a significantly more cephalic side of the injured vertebra, endplate fracture on CT, and disc injury on MRI compared with the non-IVP group ( n = 67). A multivariate logistic regression analysis was conducted to identify factors associated with IVP. The cephalic side (odds ratio [OR] = 4.183, 95% confidence interval [CI] = 1.269-13.785) and endplate fracture on CT (OR = 9.564, 95% CI = 1.940-47.143) were identified as independent factors associated with IVP. Conclusions IVP was observed in 27 (29%) of 94 intervertebral discs. The cephalic side and endplate fracture on CT were identified as independent factors associated with IVP.

[Analysis of the clinical effect of percutaneous pedicle screw fixation combined with transpedicular bone grafting in the treatment of thoracolumbar fracture].

OBJECTIVE: To investigate the clinical efficacy of percutaneous screw fixation combined with minimally invasive transpedicular bone grafting and non-bone grafting in the treatment of thoracolumbar fractures. METHODS: From Janury 2021 to June 2022, 40 patients with thoracolumbar fracture were divided into the experimental group and the control group. There were 26 patients in the experimental group, including 21 males and 5 females with an aberage age of (47.3±12.3) years old, who underwent percutaneous pedicle screw fixation combined with transpedicular autogenous bone grafting. In the control group, 14 patients received percutaneous pedicle screw fixation only. including 7 makes and 7 females with an average age of (50.2±11.2) years old. The operative time, intraoperative blood loss, anterior height ratio of injured vertebrae, Cobb angle, visual analogue score (VAS), MacNab scores, loosening or broken of the implants. were compared and analyzed. RESULTS: There was no significant difference in operation time, intraoperative blood loss, VAS and anterior height ratio of injured vertebrae between the two groups. Compared with the preoperative results, VAS and anterior height ratio of injured vertebrae were improved statistically(P<0.05). For Cobb angle of injured vertebra, there was no significant difference between the two groups before surgery (P=0.766). While at 1 week, 3 months and 12 months after surgery, there were statistically differences between the two groups (P values were 0.042, 0.007 and 0.039, respectively). The Cobb angle of injured vertebrae one year after operation was statistically decreased in both groups compared with that before surgery (P<0.001). One year after surgery, the excellent and good rate of Macnab scores was 96.15% in the experimental group and 92.86% in the control group, and there was no statistical differences between the two groups (P=0.648). There was one patient in the control group suffering superficial wound infection on the third day, which was cured by dressing change and anti-infection treatment. There were no postoperative screw loosening and broken in both groups. CONCLUSION: The two surgical methods have the advantages of less trauma, less pain and quicker recovery, which can restore the height of the injured vertebra, reconstruct the spinal sequence and reduce the fracture of the vertebral body. Transpedicular autogenous bone grafting can increase the stability of the fractured vertebra and maintain the height of the vertebra better after surgery, thus reducing the possibility of complications such as kyphosis, screw loosening and broken.

TINAVI robot-assisted one-stage anteroposterior surgery in lateral position for severe thoracolumbar fracture dislocation: A case report.

BACKGROUND: The combined anterior/posterior approach appears to be capable of reconstructing spinal stability, correcting thoracolumbar deformity, and promoting neural recovery in severe thoracolumbar fracture dislocation. However, this type of operation requires changing the body position during the procedure, resulting in a lengthy operation time. As a universal surgical robot, TINAVI robot has achieved good surgical results in clinical surgery. But to our knowledge, no reports describing TINAVI robot-assisted single lateral position anteroposterior surgery for thoracolumbar fracture dislocation. CASE SUMMARY: We describe a case of a 16-year-old female patient with severe thoracolumbar fracture and dislocation underwent surgery assisted by the TINAVI robot. A one-stage combined anterior and posterior operation was performed on a severe thoracolumbar fracture dislocation using the TINAVI robot, and the operation was completed in right lateral position. CONCLUSION: The TINAVI robot-assisted one-stage anterior and posterior surgery in right lateral position for severe thoracolumbar fracture and dislocation is both safe and effective.

Finite element study of sagittal fracture location on thoracolumbar fracture treatment.

Background: Posterior internal fixation is the main method used for the treatment of thoracolumbar fractures. Fractures often occur in the upper 1/3 of the vertebral body. However, they can also occur in the middle or lower 1/3 of the vertebral body. At present, there is no report discussing the potential effects of sagittal location on instrument biomechanics or surgical strategy. The object of this study was to investigate the effect of the sagittal location of the fracture region of the vertebral body on the biomechanics of the internal fixation system and surgical strategy. Methods: A finite element model of the T11-L3 thoracolumbar segment was established based on a healthy person's CT scan. Different sagittal fracture location finite element models were created by resection of the upper 1/3, middle 1/3, and lower 1/3 of the L1 vertebral body. Three surgical strategies were utilized in this study, namely, proximal 1 level and distal 1 level (P1-D1), proximal 2 level and distal 1 level (P2-D1), and proximal 1 level and distal 2 levels (P1-D2). Nine fixation finite element models were created by combining fracture location and fixation strategies. Range of motion, von Mises stress, and stress distribution were analyzed to evaluate the effects on the instrument biomechanics and the selection of surgical strategy. Results: In all three different fixation strategies, the maximum von Mises stress location on the screw did not change with the sagittal location of the fracture site; nevertheless, the maximum von Mises stress differed. The maximum rod stress was located at the fracture site, with its value and location changed slightly. In the same fixation strategy, a limited effect of sagittal location on the range of motion was observed. P2D1 resulted in a shorter range of motion and lower screw stress for all sagittal locations of the fracture compared with the other strategies; however, rod stress was similar between strategies. Conclusion: The sagittal location of a fracture may affect the intensity and distribution of stress on the fixation system but does not influence the selection of surgical strategy.

A Clinical Comparative Study on Percutaneous and Open Approaches for Screw Internal Fixation in Treating Thoracolumbar Fractures.

OBJECTIVE: Conventional open internal fixation surgery for thoracolumbar fractures has many complications and long recovery time. There are few clinical studies on the minimally invasive percutaneous injured vertebrae screw internal fixation. The purpose of this paper is to evaluate the application value of minimally invasive percutaneous injured vertebrae screw internal fixation in the treatment of thoracolumbar fractures (TF). METHODS: A total of 98 patients with TF admitted to our hospital from January 2019 to December 2021 were retrospectively enrolled. According to the surgical method, the patients were divided into the study group (n = 49, treated with minimally invasive percutaneous injured vertebrae screw internal fixation) and the control group (n = 49, treated with traditional open internal fixation surgery). The two groups were compared in the perioperative period, the degree of pain at different periods, the percentage of the height of the anterior edge of the injured vertebra, the Cobb angle of the injured vertebra body and the wedge angle of the injured vertebra body at the first week and the last follow-up, and the postoperative complications and the occurrence of the cone shell after the operation were recorded. Then, statistical analysis such as Student's t test or Chi-Square test was performed. RESULTS: The operation time (p = 0.002), intraoperative blood loss (p < 0.001), postoperative drainage volume (p = 0.011), and length of hospital stay (p = 0.003) in the study group were significantly lower than that in the control group. The VAS in the study group (3.38 ± 1.02) was significantly lower than that in the control group (4.56 ± 1.04) on the 7th day after the operation, with a significant difference (p < 0.001). The correction values of the percentage of leading edge height (LEH), Cobb angle, wedge angle in the study group were significantly lower than that in the control group at 1 week after surgery (all ps < 0.001). The incidence of postoperative complications in the study group (one case, 2.04%) was significantly lower than that in the control group (seven cases, 14.29%) (p = 0.031). At 1 month, 6 months, 10 months, and the last follow-up, the incidence of "empty shell" on CT scan in the study group were lower than that in the control group with a significant difference (all ps < 0.05). CONCLUSION: Applying minimally invasive percutaneous injured vertebrae screw internal fixation is more beneficial to shorten the operation time and hospital stay, with fewer postoperative complications.

A Comparison of Outcomes between the Wiltse Approach with Pedicle Screw Fixation and the Percutaneous Pedicle Screw Fixation for Multi-Segmental Thoracolumbar Fractures.

OBJECTIVE: Multi-segmental thoracolumbar fracture (MSF) generally refers to fractures occurring in two or more segments of the thoracolumbar spine. With the development of minimally invasive concept, there is little research on its application in the field of MSF. The purpose of this study is to compare two minimally invasive surgical techniques and determine which one is more suitable for treating patients with neurologically intact MSF. METHODS: We retrospectively analyzed the clinical data of 49 MSF patients with intact nerves who were admitted from January 2017 to February 2019. Among them, 25 cases underwent percutaneous pedicle screw fixation (PPSF), and 24 cases underwent Wiltse approach pedicle screw fixation (WAPSF). The operation time, number of fixed segments, blood loss, length of incision, postoperative ambulation time, accuracy of pedicle screw placement, facet joint violation (FJV), number of C-arm exposures, as well as pre- and postoperative visual analogue scale (VAS), Oswestry disability index (ODI), local Cobb's angle (LCA), and percentage of anterior vertebral body height (PAVBH) were recorded for both groups. Paired sample t-test was used for intra-group comparison before and after surgery while independent sample t-test was used for inter-group comparison. RESULTS: The differences in the number of fixed segments, intraoperative bleeding, postoperative bed time, accuracy rate of pedicle screw placement, VAS, and ODI between the two groups were not statistically significant (p > 0.05). However, the operative time and total surgical incision length were significantly shorter in the WAPSF group than in the PPSF group (p < 0.05), and the FJV was significantly higher in the PPSF group than in the WAPSF group (p < 0.05). Also, the PPSF group received more intraoperative fluoroscopy (p < 0.05). The result of LCA and PAVBH in the WAPSF group were significantly better than in the PPSF group (p < 0.05). CONCLUSIONS: Both PPSF and WAPSF were found to be safe and effective in the treatment of MSF without neurological deficits through our study. However, considering radiation exposure, FJV, vertebral height restoration, correction of kyphosis, and learning curve, WAPSF may be a better choice for neurologically intact MSF.