Outcomes for standalone anterolateral corpectomy for thoracolumbar burst fractures.

There is a paucity of data available on the context preceding anterior fusion failure or the need for a posterior fusion, the timing of the second operation, or any correlation between the different instrumentation and failure rates. A retrospective chart review was performed of 131 identified patients who underwent anterolateral corpectomy and fusion for a thoracolumbar burst fracture from 2000 to 2012 in a single institution. 96 patients had clinical and radiographic follow up of greater than two months. Mean kyphosis correction from preoperative (14.1°) to postoperative kyphosis (6.3°) was 7.7° and 37% had loss of kyphotic correction at follow-up. In a univariate analysis, use of a bone strut graft (OR 3.2, p = 0.01), point-loaded graft position (OR 4.9, p = 0.005), end plate damage/subsidence (OR 6.7, p < 0.0001), and graft to endplate width ratio of ≤ 45% on AP x-ray (OR 3.0, p = 0.02) were associated with loss of kyphotic correction. 41% demonstrated scoliosis of ≥ 5° at follow-up. Graft location towards the left of midline (OR 8.6, p < 0.0001), point-loaded graft position (OR 3.8, p = 0.01), and end plate damage/subsidence (OR 5.5, p = 0.0001) were also associated with scoliosis at the time of final follow-up. Five patients required posterior fusion and fifteen patients continued to have daily pain, only one of which was determined to be related to kyphosis. Use of a bone strut graft versus expandable cage, graft location, graft position, presence of early or late subsidence and width of the graft may be associated with loss of kyphotic correction and scoliosis.

Effect of screw insertion depth into fractured vertebrae in the treatment of thoracolumbar fractures.

PURPOSE: The study's objective was to assess the effect of the screw insertion depth into fractured vertebrae in treating thoracolumbar fractures. MATERIALS AND METHODS: This was a retrospective analysis of 92 patients with thoracolumbar fractures from December 2018 to February 2020. Patients had AO type A2, A3 thoracolumbar fractures. The patients were divided into two groups according to the screw insertion depth. The vertebral wedge angle (VWA), Cobb angle (CA), anterior vertebral body height (AVBH), middle vertebral body height (MVBH), visual analog scale (VAS) score, and Oswestry Disability Index (ODI) were compared preoperatively and at one week and 12 months postoperatively. The correlation between Vertebral height loss and potential risk factors, such as sex, age, BMD and BMI was evaluated. RESULTS: Compared with the preoperative data, the postoperative clinical and radiographic findings were significantly different in both groups, But no significant difference between the two groups at 1 week. At 1 year postoperatively, there was a significant difference in the CA (p < 0.0001), VWA (p = 0.047), AVBH (p < 0.0001), MVBH (p < 0.0001), VAS score (p < 0.0001), and ODI (p < 0.0001) between the two groups, Except for age, bone density and other influencing factors the long screw group had better treatment results than the short screw group. CONCLUSION: A longer screw provides greater grip on the fractured vertebral body and stronger support to the vertebral plate. The optimal screw placement depth exceeds 60% of the vertebral body length on the lateral view.

Using QCT for the prediction of spontaneous age- and gender-specific thoracolumbar vertebral fractures and accompanying distant vertebral fractures.

PURPOSE: To investigate the value and age- and gender-specific threshold values of bone mineral density (BMD) by quantitative computed tomography (QCT) for the prediction of spontaneous thoracolumbar vertebral fractures and thoracolumbar junction fractures accompanying distant vertebral fractures. METHODS: Among the 556 patients included, 68 patients had thoracolumbar vertebral fractures (12 patients with distant vertebral fractures, 56 patients without distant vertebral fractures) and 488 patients had no vertebral fractures. All patients were grouped by gender and age. According to the principle of Youden index, the threshold values were calculated from receiver operating characteristic (ROC) curves. RESULTS: The threshold values for predicting thoracolumbar vertebral fractures were 89.8 mg/cm3 for all subjects, 90.1 mg/cm3 for men, and 88.6 mg/cm3 for women. The threshold values for men aged < 60 years old and ≥ 60 years old were 117.4 mg/cm3 and 87.5 mg/cm3, respectively. The threshold values for women aged < 60 years old and ≥ 60 years old were 88.6 and 68.4 mg/cm3, respectively. The threshold value for predicting spontaneous thoracolumbar junction fractures with distant vertebral fractures was 62.7 mg/cm3. CONCLUSIONS: QCT provides a good ability to predict age- and gender-specific spontaneous thoracolumbar vertebral fractures, and to further predict spontaneous thoracolumbar junction fractures with distant vertebral fractures.

Feasibility study in quantitative identification of fresh and old osteoporotic vertebral compression fracture by vertebral CT value and CT value difference.

BACKGROUND: This study aims to assess the diagnostic utility of vertebral CT value and CT value difference in distinguishing between fresh and old osteoporotic vertebral compression fractures (OVCF). METHODS: A retrospective analysis was conducted on 118 patients with OVCF who underwent both MRI and CT examinations at our hospital. The nature of the fractured vertebra was determined according to MRI. The CT value of the fractured vertebrae and the mean CT value of the adjacent normal vertebrae were measured separately, and the differences between these values were calculated. Independent samples t-tests were used to compare CT value and CT value difference among all groups. The receiver operating characteristic (ROC) curve was employed to determine the optimal cut-off value for both CT value and CT value difference in differentiating fresh and old fractures. RESULTS: The study included a total of 163 fractured vertebrae from 118 patients. The CT value of fresh fractured vertebrae was significantly higher than those of adjacent normal vertebrae, which was statistically different (P < 0.001). In contrast, the difference between CT value of old fractured vertebrae and those of adjacent normal vertebrae was not statistically significant (P > 0.05). There were significant differences in CT value and CT value difference between fresh fractured vertebrae and old fractured vertebrae (P < 0.001). The ROC curve analysis showed that the optimal cut-off value of CT value for fresh fractures and old fractures was 103.40 HU. The optimal cut-off value of CT value difference was 39.81 HU. CONCLUSION: Vertebral CT value and CT value difference offer a certain reference value for distinguishing between fresh and old OVCF. These parameters can serve as a rapid diagnostic tool when MRI is unavailable or impractical, aiding in the timely assessment of OVCF.

Traumatic multiple-level continuous and noncontinuous thoracolumbar spinal fractures management in adult patients: A single-center experience.

BACKGROUND: This study aimed to describe our clinical experience with surgical approaches and patient management for traumatic multiple-level continuous and noncontinuous thoracolumbar spinal fractures. METHODS: We retrospectively evaluated patients with continuous and noncontinuous multiple-level thoracolumbar fractures who were operated on by the same surgical team from 2019 to 2021. These patients were divided into two groups: Group 1 (n=12, continuous fractures) and Group 2 (n=14, noncontinuous fractures). We assessed the patients' age, gender, fracture levels, fracture type, classification according to the AO (Arbeitsgemeinschaft für Osteosynthesefragen) Spine Thoracolumbar Fracture Classification, status of posterior ligament damage, presence of additional traumatic pathology, status of decompression via laminectomy, levels of stabilization and fusion, preoperative and postoperative neurological status, presence of cervical trauma, duration of operation, amount of blood loss, duration of hospitalization, and lordosis and kyphosis angles in terms of fusion status and postoperative follow-up over two years. The study excluded patients over the age of 65, those with single-level fractures, and pathological fractures caused by osteoporosis, infection, or spinal tumors. RESULTS: Gender, age, neurological status, application of laminectomy, surgical complications, status of cervical fracture, duration of operation, amount of blood loss, duration of hospitalization, lordosis, and kyphosis angles were uniformly distributed between the groups. All patients underwent fusions, ranging from three to eight, with a median of two (range 2-4) fracture levels, and a median of five instrumented vertebrae, ranging from four to seven. Significant differences between the two groups were observed in terms of operation duration (p=0.001), blood loss (p=0.010), duration of hospitalization (p=0.003), number of fusions (p<0.001), and instrumented vertebral segments (p=0.011). CONCLUSION: Thus, a surgical approach involving decompression, vertebral fusion screws, allografts, and bone substitutes can enhance surgical outcomes for patients with continuous and noncontinuous vertebral fractures.

A novel unilateral extrapedicular approach applied to percutaneous vertebral augmentation to treat thoracic and lumbar Osteoporotic Vertebral Compression Fracture: a retrospective study.

OBJECTIVE: To design and apply a novel puncture method, named P TO P technique, and to evaluate its efficacy and safety. METHOD: The data of patients treated with PVA in medical institution from January 2020 to December 2022 were reviewed and analyzed. The degree of pain relief and recovery from daily activities were evaluated using VAS and LAS scores, and radiological parameters were evaluated using local kyphosis angle and excellent cement distribution. Complications such as cement leakage and recurrent vertebral fractures were also recorded. RESULTS: 157 patients with thoracolumbar OVCF were successfully treated with novel puncture techniques. All postoperative clinical and radiological parameters significantly decreased in all patients, except for an increase in local kyphosis angle at the last follow-up compared to postoperative. All other above indicators remained statistically significant at the last follow-up compared to postoperative improvement. Except for 2 patients with poor cement distribution, the remaining 155 patients successfully achieved satisfactory results in unilateral puncture and bilateral cement distribution, achieving an excellent rate of 98.73%. In addition, 18 cases (11.46%) of cement leakage occurred during the operation, fortunately none of them were uncomfortable. During the postoperative follow-up period, 4 cases (2.55%) of recurrent fractures occurred. No other serious complications such as neurologic or named vascular injuries occurred. CONCLUSION: The application of P TO P technology in thoracolumbar OVCF patients is safe and effective. It can not only reduce pain and quickly recover daily activities, but also achieve the perfect effect of unilateral puncture and bilateral cement filling.

Effects of Lumbar Spine Vertebral Fractures on Trabecular Bone Score (TBS): The Manitoba BMD Registry.

Trabecular bone score (TBS) is a BMD-independent risk factor for fracture. During BMD reporting, it is standard practice to exclude lumbar vertebral levels affected by structural artifact. It is uncertain whether TBS is affected by lumbar spine fractures. The current study examined the effect of lumbar spine compression fractures on TBS measurements. We identified 656 individuals with vertebral fractures (mean age 75.8 ± 7.9 years, 90.9% female) who had lumbar spine DXA, TBS measurements from L1-L4 and vertebral fracture assessment (VFA) for identifying vertebral fractures. There were 272 cases with lumbar spine fractures and 384 controls with only thoracic spine fractures. L1 TBS and BMD were significantly greater in those with than without lumbar fractures (p< 0.001) but did not significantly differ for other vertebral levels or for L1-L4 combined. TBS and BMD measurements were then renormalized to remove level-specific differences (denoted rTBS and rBMD). The mean difference (all fractured minus all non-fractured vertebrae) was +0.040 (+3.3%) for rTBS and +0.088 g/cm2 (+9.5%) for rBMD (both p <0.001). The largest effect was for L1 with mean difference +0.058 (+4.9%) for rTBS and +0.098 g/cm2 (+10.6%) for rBMD (both p <0.001). The mean difference between fractured and non-fractured levels for rTBS was +0.028 (+2.4%) for grade 1, +0.036 (+3.0%) for grade 2 and +0.059 (+5.0%) for grade 3 fractures; for rBMD +0.051 (+5.5%), +0.076 (+8.2%) and +0.151 (+16.4%) g/cm2, respectively. The impact of excluding lumbar vertebral levels with fracture from the L1-L4 TBS measurement overall was small (-0.011 [-1.0%]; p<0.001) and was also small for grade 3 fractures (-0.020 [-1.7%]; p<0.001). In summary, TBS is mildly increased by VFA-confirmed lumbar vertebral fractures, but the percentage effect is much smaller (less than half) than seen for BMD and minimally affects TBS measured from L1-L4. This would support the use of L1-L4 without exclusions in individuals with lumbar vertebral fractures.

Suboptimal osteoporosis care in hospitalized patients: a retrospective analysis of vertebral compression fractures detected on computed tomography.

Vertebral compression fractures (VCFs) are the most common osteoporotic fractures. Only 1/3 of patients with VCFs are clinically diagnosed. In our institution, the Fracture Liaison Service (FLS) was launched in 2017 to improve osteoporosis management for hospitalized patients. (1) To assess osteoporosis awareness among medical providers for emergency department (ED)/hospitalized patients aged 50 or greater; (2) To estimate the rate of FLS consults or referrals to primary care providers (FLS/PCP) by primary teams. A centralized radiology system was used to examine all thoracic and lumbar computed tomography (CT) scans conducted between June 1, 2017 and June 1, 2022. 449 studies were identified with the radiologic impression "compression fracture". 182 studies were excluded after manual chart review. 267 hospitalizations/ED visits with lumbar and/or thoracic spine CT scans were included. Referrals to FLS (26) or PCP (27) were made in 53 cases (~ 20% of the total). In the ED subgroup (131 hospitalizations), only 17 patients had FLS/PCP referrals. The "compression fracture" was mentioned in 227 (85%) discharge notes (any part), while "osteoporosis" was mentioned in only 74 (28%) hospitalizations. A statistically significant difference was found between the two groups when "osteoporosis" was mentioned in the "assessment and plan" section (p = 0.02). Our data show that the overall osteoporosis care for affected patients is suboptimal. Medical providers often overlook the presence of osteoporosis, leading to a lack of consultation with the FLS of referral to PCPs for further evaluation and treatment.

Clinical application of a modified wiltse approach in middle and lower thoracic vertebrae: a case-control study of thoracic fracture patients.

BACKGROUND: The Wiltse approach has been extensively employed in thoracolumbar surgeries due to its minimal muscle damage. However, in the middle and lower thoracic spine, the conventional Wiltse approach necessitates the severance of the latissimus dorsi and trapezius muscles, potentially leading to muscular injury. Consequently, we propose a modified Wiltse approach for the middle and lower thoracic vertebrae, which may further mitigate muscular damage. METHODS: From May 2018 to April 2022, 60 patients with spinal fractures in the middle and lower thoracic vertebrae (T5-12) were enrolled in this study. Thirty patients underwent surgery using the modified Wiltse approach (Group A), while the remaining 30 patients received traditional posterior surgery (Group B). The observation indices included operation time, intraoperative blood loss, incision length, number of C-arm exposures, postoperative drainage, postoperative ambulation time, discharge time, as well as preoperative and postoperative Cobb's angle, percentage of anterior vertebral body height (PAVBH), visual analog scale (VAS) Score, and Oswestry disability index (ODI). RESULTS: Compared to the traditional posterior approach, the modified Wiltse approach demonstrated significant advantages in operation time, intraoperative blood loss, length of incision, postoperative ambulation time, postoperative drainage, and discharge time, as well as postoperative VAS and ODI scores. No significant differences were observed between the two groups in terms of number of C-arm exposures, postoperative Cobb's angle, or postoperative PAVBH. CONCLUSION: We propose a modification of the Wiltse approach for the middle and lower thoracic vertebral regions, which may further minimize muscular damage and facilitate the recovery of patients who have undergone surgery in the middle and lower thoracic vertebrae.

A Case of a Cerebrospinal Fluid Leak Secondary to Chiropractic Manipulation of the Thoracic Spine.

Chiropractic spinal manipulation therapy (CSMT) of the cervical spine has been reported to cause mechanical dural injuries that result in cerebrospinal fluid (CSF) leaks. We present a case of symptomatic intracranial hypotension after isolated thoracic CSMT. Initial imaging was unable to definitively localize the CSF leak, but dynamic imaging was able to better identify the defect. Multiple epidural blood patches were attempted, including image-guided approaches and with fibrin sealant, but surgical repair was ultimately required. Our case illustrates the risk of dural tear in the setting of recent CSMT and the challenges of managing such an injury.

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% ±â€…7.5% and 9.9°â€…±â€…3.8°, respectively, the values of the loss were 6.5% ±â€…4.0% and 3.9°â€…±â€…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.

Finite Element Analysis of Bilateral Double Rod Constructs in Thoracolumbar Fractures.

AIM: To evaluate bilateral double rod contructs in thoracolumbar fractures in a Finite Element model MATERIAL and METHODS: A computed tomography of a 35-year old male have been chosen to create a vertebra model and 1/3 of the T12 was removed to create the burst fracture model. In model A, transpedicular polyaxial screws were inserted two levels above and two levels below the burst fracture. On each side the screws were connected with a single rod. In model B, the screws were connected with two rods on each side attached to two lateral connectors. A uniform 150 N axial load and 10 N/m torque was applied on the superior T10. RESULTS: ROM and von Mises stress nephrograms revealed that the bilateral double-rod construct is being the most rigid and that the force on the pedicle screws were significantly lower compared to model A. CONCLUSION: We believe that bilateral double-rod constructs for the stabilization of thoracolumbar fractures have a decreased load on pedicle screws and rods compared to the classic bilateral single rod stabilization system and can lower the risk of implant failure and the risk for secondary complications and revision surgery.

Influence of Hospital Transfer Status on Surgical Outcomes for Traumatic Thoracolumbar Spine Fractures: Insights from a Multicenter Investigation.

OBJECTIVE: Surgical intervention for unstable thoracolumbar spine fractures is common, but delayed management and complications can impact outcomes. This study compares perioperative outcomes between patients directly admitted and those transferred from another facility for thoracolumbar spine surgery, aiming to identify predictors of complications and mortality. METHODS: A multicenter retrospective cohort study used the American College of Surgeons National Surgical Quality Improvement Program database from 2011 to 2021 identified 61,626 patients undergoing fusion surgeries for thoracolumbar spine fractures, excluding spinal cord injury or pathological fractures. Patients were categorized as Direct (admitted from the emergency department) and Transfer (transferred from another facility). Perioperative outcomes, including operative time, length of stay (LOS), 30-day mortality, and complications, were compared. RESULTS: Our patient population (54.3% female, mean age 62.4 ± 12.9 years) comprised 12.2% Transfer and 87.8% Direct patients. Following propensity score matching, Transfer patients had a longer hospital LOS (5.1 ± 5.7 days vs. 4.5 ± 4.6 days, P < 0.001). Transfer exhibited higher rates of superficial incisional surgical site infection (1.7% vs. 1.1%, P = 0.003), sepsis (1.7% vs. 1.3%, P = 0.038), pneumonia (1.7% vs. 1.2%, P = 0.019), postoperative reintubation (0.9% vs. 0.6%, P = 0.036), and failure to wean off ventilator >48 hours postsurgery (0.7% vs. 0.3%, P = 0.005) compared to Direct admissions. Direct group had a higher rate of perioperative transfusion (16.5% vs. 13.4%, P < 0.001). Transfer patients also had a higher 30-day mortality rate compared to Direct admissions (1.1% vs. 0.6%, P = 0.002). CONCLUSIONS: Interhospital transfers significantly affect hospital LOS, postoperative morbidity, and mortality in thoracolumbar spine surgery. Enhancing postoperative monitoring for transfer patients is crucial.

Development and validation of a predictive model for preoperative deep vein thrombosis following traumatic thoracolumbar fractures.

Although a sequential work-up for deep vein thrombosis has reached agreement worldwide, the mysterious nature of DVT following fractures brings challenges to early diagnosis and intervention. The objective of the present study was to develop and validate a nomogram for predicting preoperative DVT risk in patients with thoracolumbar fractures using readily available clinical data. Of the 1350 patients, 930 were randomly assigned to the training cohort. A prediction model was established and visualized as a nomogram based on eight predictors related to preoperative DVT. The performance of the model was tested by the receiver operating characteristic curve, Hosmer-Lemeshow test, calibration curve, and decision curve analysis. We further verified the model in the validation cohort. The AUCs of the prediction model were 0.876 and 0.853 in training and validation cohorts, respectively. The Hosmer-Lemeshow test demonstrated good fitness in the training set (X2 = 5.913, P = 0.749) and the validation set (X2 = 9.460, P = 0.396). Calibration and decision curve analyses performed well in training and validation sets. In short, we developed a prediction model for preoperative DVT risk in patients with thoracolumbar fractures and verified its accuracy and clinical utility.

[Robot-assisted versus traditional fluoroscopy-assisted posterior fixation in treatment of thoracolumbar fractures with ankylosing spondylitis: a retrospective study].

Objective: To compare the effectiveness of robot-assisted (RA) minimally invasive surgery versus traditional fluoroscopy-assisted (FA) open posterior fixation surgery in treating thoracolumbar fractures with ankylosing spondylitis (AS). Methods: A clinical data of 21 cases of thoracolumbar fractures with AS who met the selection criteria between December 2016 and December 2023 was retrospectively analyzed. Ten cases underwent RA minimally invasive surgery group (RA group) and 11 cases underwent FA open posterior fixation surgery (FA group). There was no significant difference in gender, age, fracture segment distribution, fracture type, time from injury to surgery, visual analogue scale (VAS) score, and American Spinal Injury Association (ASIA) grading between RA group and FA group ( P>0.05). The operation time, intraoperative blood loss, radiation exposure time, radiation dose, hospital stay, and complications of the two groups were recorded. According to Gertzbein-Robbins criteria, the accuracy of screw implantation was evaluated by CT within 1 week after surgery. During follow-up, pain and nerve function were evaluated by VAS score and ASIA grading. Results: All patients underwent surgery successfully, and there was no significant difference in operation time ( P>0.05). The intraoperative blood loss and hospital stay in the RA group were significantly less than those in the FA group ( P<0.05), and the radiation exposure time and radiation dose were significantly more than those in the FA group ( P<0.05). A total of 249 pedicle screws were implanted in the two groups, including 118 in the RA group and 131 in the FA group. According to the Gertzbein-Robbins criteria, the proportion of clinically acceptable screws (grades A and B) in the RA group was significantly higher than that in the FA group ( P<0.05). Patients in both groups were followed up 3-12 months, with an average of 6.8 months. The VAS scores of the two groups after surgery were significantly lower than those before surgery, and the differences were significant ( P<0.05). The RA group had lower scores than the fluoroscopy group at 1 week and 3 months after surgery ( P<0.05). There was no significant difference in neurological function grading between groups at 1 week and 3 months after surgery ( P>0.05). In the FA group, 1 case of deep infection and 1 case of deep vein thrombosis of lower extremity occurred, while no complication occurred in the RA group, and there was no significant difference in the incidence of complications between groups ( P>0.05). Conclusion: Both RA minimally invasive surgery and FA open posterior fixation surgery can achieve good effectiveness. Compared with the latter, the former has more advantages in terms of intraoperative blood loss, hospital stay, and accuracy of pedicle screw insertion.

Extent of Traumatic Spinal Cord Injury Is Lesion Level Dependent and Predictive of Recovery: A Multicenter Neuroimaging Study.

Assessing the extent of the intramedullary lesion after spinal cord injury (SCI) might help to improve prognostication. However, because the neurological level of injury impacts the recovery potential of SCI patients, the question arises whether lesion size parameters and predictive models based on those parameters are affected as well. In this retrospective observational study, the extent of the intramedullary lesion between individuals who sustained cervical and thoracolumbar SCI was compared, and its relation to clinical recovery was assessed. In total, 154 patients with subacute SCI (89 individuals with cervical lesions and 65 individuals with thoracolumbar lesions) underwent conventional clinical magnetic resonance imaging 1 month after injury and clinical examination at 1 and 12 months. The morphology of the focal lesion within the spinal cord was manually assessed on the midsagittal slice of T2-weighted magnetic resonance images and compared between cervical and thoracolumbar SCI patients, as well as between patients who improved at least one American Spinal Injury Association Impairment Scale (AIS) grade (converters) and patients without AIS grade improvement (nonconverters). The predictive value of lesion parameters including lesion length, lesion width, and preserved tissue bridges for predicting AIS grade conversion was assessed using regression models (conditional inference tree analysis). Lesion length was two times longer in thoracolumbar compared with cervical SCI patients (F = 39.48, p < 0.0001), whereas lesion width and tissue bridges width did not differ. When comparing AIS grade converters and nonconverters, converters showed a smaller lesion length (F = 5.46, p = 0.021), a smaller lesion width (F = 13.75, p = 0.0003), and greater tissue bridges (F = 12.87, p = 0.0005). Using regression models, tissue bridges allowed more refined subgrouping of patients in AIS groups B, C, and D according to individual recovery profiles between 1 month and 12 months after SCI, whereas lesion length added no additional information for further subgrouping. This study characterizes differences in the anteroposterior and craniocaudal lesion extents after SCI. The two times greater lesion length in thoracolumbar compared with cervical SCI might be related to differences in the anatomy, biomechanics, and perfusion between the cervical and thoracic spines. Preserved tissue bridges were less influenced by the lesion level while closely related to the clinical impairment. These results highlight the robustness and utility of tissue bridges as a neuroimaging biomarker for predicting the clinical outcome after SCI in heterogeneous patient populations and for patient stratification in clinical trials.

A Prediction Nomogram for Fractured Vertebra Recollapse After Posterior Reduction and Pedicle Screw Fixation in Thoracolumbar Fractures.

OBJECTIVE: This study aimed to establish a predictive nomogram model for recollapse of fractured vertebra after posterior pedicle screw fixation in thoracolumbar fractures (TLFs). METHODS: Patients undergoing posterior pedicle screw fixation for TLFs at our hospital between January 2016 and December 2021 were retrospectively reviewed. Patients were divided into 2 groups according to the presence or absence of recollapse of the fractured vertebra at the final follow-up. The predictors for fractured vertebra recollapse were identified by univariate and multivariable logistic regression analysis, and a nomogram model was developed. The prediction performance and internal validation were established. RESULTS: A total of 224 patients were included in this study. Of these, 46 (20.5%) patients developed recollapse of fractured vertebra. Age, thoracic and lumbar injury severity score, screw distribution in the fractured vertebra, and anterior vertebral height compression ratio were associated with vertebral recollapse. These predictors were used to construct a predictive nomogram. The area under the receiver operating characteristic curve of the nomogram model was 0.891. The concordance index was 0.891, and it was 0.877 with bootstrapping validation. The calibration curves and decision curve analysis also suggested that the nomogram model had excellent predictive performances for fractured vertebra recollapse. CONCLUSIONS: A clinical nomogram incorporating 4 variables was constructed to predict fractured vertebra recollapse after posterior pedicle screw fixation for TLFs. The nomogram demonstrated good calibration and discriminative abilities, which may help clinicians to make better treatment decisions.