Biomechanical analysis of adjacent segments after correction surgery for adult idiopathic scoliosis: a finite element analysis.

The biomechanical aspects of adjacent segment degeneration after Adult Idiopathic Scoliosis (AdIS) corrective surgery involving postoperative changes in motion and stress of adjacent segments have yet to be investigated. The objective of this study was to evaluate the biomechanical effects of corrective surgery on adjacent segments in adult idiopathic scoliosis by finite element analysis. Based on computed tomography data of the consecutive spine from T1-S1 of a 28-year-old male patient with adult idiopathic scoliosis, a three-dimensional finite element model was established to simulate the biomechanics. Two posterior long-segment fixation and fusion operations were designed: Strategy A, pedicle screws implanted in all segments of both sides, and Strategy B, alternate screws instrumentation on both sides. The range of motion (ROM), Maximum von Mises stress value of intervertebral disc (IVD), and Maximum von Mises stress of the facet joint (FJ) at the fixation adjacent segment were calculated and compared with data of the preoperative AdIS model. Corrective surgery decreased the IVD on the adjacent segments, increased the FJ on the adjacent segments, and decreased the ROM of the adjacent segments. A greater decrease of Maximum von Mises stress was observed on the distal adjacent segment compared with the proximal adjacent segment. The decrease of Maximum von Mises stress and increment of Maximum von Mises stress on adjacent FJ in strategy B was greater than that in strategy A. Under the six operation modes, the change of the Maximum von Mises stress on the adjacent IVD and FJ was significant. The decrease in ROM in the proximal adjacent segment was greater than that of the distal adjacent segment, and the decrease of ROM in strategy A was greater than that in strategy B. This study clarified the biomechanical characteristics of adjacent segments after AdIS corrective surgery, and further biomechanical analysis of two different posterior pedicle screw placement schemes by finite element method. Our study provides a theoretical basis for the pathogenesis, prevention, and treatment of adjacent segment degeneration after corrective surgery for AdIS.

CT-derived vertebral bone mineral density is a useful biomarker to predict COVID-19 outcome.

The low vertebral bone computed tomography (CT) Hounsfield unit values measured on CT scans reflect low bone mineral density (BMD) and are known as diagnostic indicators for osteoporosis. The potential prognostic significance of low BMD defined by vertebral bone CT values for the coronavirus disease 2019 (COVID-19) remains unclear. This study aimed to assess the impact of BMD on the clinical outcome in Japanese patients with COVID-19 and evaluate the association between BMD and critical outcomes, such as high-flow nasal cannula, non-invasive and invasive positive pressure ventilation, extracorporeal membrane oxygenation, or death. We examined the effects of COVID-19 severity on the change of BMD over time. This multicenter retrospective cohort study enrolled 1132 inpatients with COVID-19 from the Japan COVID-19 Task Force database between February 2020 and September 2022. The bone CT values of the 4th, 7th, and 10th thoracic vertebrae were measured from chest CT images. The average of these values was defined as BMD. Furthermore, a comparative analysis was conducted between the BMD on admission and its value 3 months later. The low BMD group had a higher proportion of critical outcomes than did the high BMD group. In a subanalysis stratifying patients by epidemic wave according to onset time, critical outcomes were higher in the low BMD group in the 1st-4th waves. Multivariable logistic analysis of previously reported factors associated with COVID-19 severity revealed that low BMD, chronic kidney disease, and diabetes were independently associated with critical outcomes. At 3 months post-infection, patients with oxygen demand during hospitalization showed markedly decreased BMD than did those on admission. Low BMD in patients with COVID-19 may help predict severe disease after the disease onset. BMD may decrease over time in patients with severe COVID-19, and the impact on sequelae symptoms should be investigated in the future.

Trabecular bone mineral density as measured by thoracic vertebrae predicts incident hip and vertebral fractures: the multi-ethnic study of atherosclerosis.

We evaluated the relationship of bone mineral density (BMD) by computed tomography (CT), to predict fractures in a multi-ethnic population. We demonstrated that vertebral and hip fractures were more likely in those patients with low BMD. This is one of the first studies to demonstrate that CT BMD derived from thoracic vertebrae can predict future hip and vertebral fractures. PURPOSE/INTRODUCTION: Osteoporosis affects an enormous number of patients, of all races and both sexes, and its prevalence increases as the population ages. Few studies have evaluated the association between the vertebral trabecular bone mineral density(vBMD) and osteoporosis-related hip fracture in a multiethnic population, and no studies have demonstrated the predictive value of vBMD for fractures. METHOD: We sought to determine the predictive value of QCT-based trabecular vBMD of thoracic vertebrae derived from coronary artery calcium scan for hip fractures in the Multi-Ethnic Study of Atherosclerosis(MESA), a nationwide multicenter cohort included 6814 people from six medical centers across the USA and assess if low bone density by QCT can predict future fractures. Measures were done using trabecular bone measures, adjusted for individual patients, from three consecutive thoracic vertebrae (BDI Inc, Manhattan Beach CA, USA) from non-contrast cardiac CT scans. RESULTS: Six thousand eight hundred fourteen MESA baseline participants were included with a mean age of 62.2 ± 10.2 years, and 52.8% were women. The mean thoracic BMD is 162.6 ± 46.8 mg/cm3 (95% CI 161.5, 163.7), and 27.6% of participants (n = 1883) had osteoporosis (T-score 2.5 or lower). Over a median follow-up of 17.4 years, Caucasians have a higher rate of vertebral fractures (6.9%), followed by Blacks (4.4%), Hispanics (3.7%), and Chinese (3.0%). Hip fracture patients had a lower baseline vBMD as measured by QCT than the non-hip fracture group by 13.6 mg/cm3 [P < 0.001]. The same pattern was seen in the vertebral fracture population, where the mean BMD was substantially lower 18.3 mg/cm3 [P < 0.001] than in the non-vertebral fracture population. Notably, the above substantial relationship was unaffected by age, gender, race, BMI, hypertension, current smoking, medication use, or activity. Patients with low trabecular BMD of thoracic vertebrae showed a 1.57-fold greater risk of first hip fracture (HR 1.57, 95% CI 1.38-1.95) and a nearly threefold increased risk of first vertebral fracture (HR 2.93, 95% CI 1.87-4.59) compared to normal BMD patients. CONCLUSION: There is significant correlation between thoracic trabecular BMD and the incidence of future hip and vertebral fracture. This study demonstrates that thoracic vertebrae BMD, as measured on cardiac CT (QCT), can predict both hip and vertebral fractures without additional radiation, scanning, or patient burden. Osteopenia and osteoporosis are markedly underdiagnosed. Finding occult disease affords the opportunity to treat the millions of people undergoing CT scans every year for other indications.

The effect of electromyography triggered electrical stimulation to abdominal muscles on sitting balance, respiratory functions, and abdominal muscle thickness in complete spinal cord injury: a randomized controlled trial.

Complete thoracic spinal cord injury (SCI) results in a loss of innervation to the abdominal muscles, which affects trunk stability and performance of activities of daily living from a sitting position. Respiratory function is also affected, leading to frequent pulmonary complications. Given the importance of trunk stability and respiratory function, we investigated the effects of electromyography triggered electrical stimulation (EMG-ES) applied to the abdominal muscles on sitting balance, respiratory functions and abdominal muscle thickness in individuals with complete thoracic SCI. This randomized controlled study included 34 participants with complete thoracic SCI who were randomly allocated to the experimental group ( n  = 17) and the control group ( n  = 17). During the 4-week intervention period, the experimental group received EMG-ES to their abdominal muscles, while the control group received isometric abdominal exercises three times per week. Both groups continued with their routine rehabilitation program (active or passive range of motion exercises, stretching, and balance coordination exercises). The primary outcome measures were the modified functional reach test (mFRT) and trunk control test (TCT). Secondary outcome measures included a pulmonary function test (PFT) and the bilateral abdominal muscle thicknesses using ultrasonography. At the end of the study, the experimental group showed significantly greater improvements in both primary outcomes. The mean difference in pre-post changes between the groups for the mFRT area was 242.8 cm² [95% confidence interval (CI): 181.3-329.8; effect size 0.92; P  < 0.001] and 5.0 points for TCT (95% CI: 3.9-6.0; effect size 0.98, P  < 0.001). The increase in the abdominal muscle thickness was also significantly greater in the experimental group ( P  < 0.001) without significant differences in the PFT ( P  > 0.05). We conclude that adding EMG-ES of abdominal muscles may further improve sitting balance and abdominal muscle thickness in individuals with complete thoracic SCI.

Effects of 4-week downhill treadmill walking on the vertebral angle and postural muscle activity in participants with thoracic kyphosis and forward head posture: A comparative longitudinal study.

BACKGROUND: Maintaining correct posture and optimal spine function has become an important issue due to the increased use of computers and smartphones. OBJECTIVE: To investigate the effect of a 4-week downhill treadmill exercise (DTWE) program on participants with thoracic kyphosis and forward head posture (FHP). METHODS: Twenty-eight male participants were randomly assigned to the DTWE (n= 14) or standard treadmill walking exercise (STWE) (n= 14) group. They performed 30-minute exercise three times a week for 4 weeks. The vertebral angle was measured using a three-dimensional (3D) motion analysis system. Surface electromyography (EMG) was performed to record muscle activity in the thoracic erector spinae (TES), sternocleidomastoid muscle (SCM), and cervical erector spinae (CES). RESULTS: The DTWE group showed significant increases in the craniovertebral angle (CVA) and TES EMG activity and significant decreases in the thoracic kyphosis angle and SCM and CES EMG activity compared with those shown by the STWE group following the intervention (p< 0.05). However, lumbar lordosis or pelvic tilt angles did not differ significantly between the groups after the intervention (p> 0.05). CONCLUSIONS: DTWE can be effective in reducing thoracic kyphosis and FHP without causing compensatory movements of the lumbar spine and pelvis.

Efficacy analysis of one-stage posterior-only surgical treatment for thoracic spinal tuberculosis in the T4-6 segments with minimum 5-year follow-up.

In recent years, with the in-depth research on spinal tuberculosis, posterior surgery alone has been praised highly by more and more surgeons due to the better correction of kyphosis, better maintenance of spinal physiological curvature, smaller surgical trauma and fewer surgical complications. However, there is currently lack of relevant reports about the efficacy of posterior surgery alone in the treatment of tuberculosis in the T4-6 segments. This study aimed to evaluate the clinical study efficacy and feasibility of one-stage posterior-only surgical treatment for thoracic spinal tuberculosis in the T4-6 segments. 67 patients with tuberculosis in T4-6 segments who underwent one-stage posterior-only surgery were included in this study. The clinical efficacy was evaluated using statistical analysis based on the data about erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), Oswestry Dability Index (ODI) score, Visual Analogue Scale (VAS) score and Cobb angle before surgery, after surgery and at the last follow-up. All patients completed fusion during the follow-up period of 6-9 months. ESR and CRP were returned to normal for all patients at 6 months follow-up. In the meanwhile, among the 27 patients combined with neurological impairment, neurological functions of 22 cases (81.48%) recovered completely at the last follow-up (P < 0.05). Cobb angle of the kyphosis was improved from preoperative 34.8 ± 10.9° to postoperative 9.6 ± 2.8°, maintaining at 11.3 ± 3.2° at the last follow-up, The ODI and VAS scores were improved by 77.10% and 81.70%, respectively. This 5-year follow-up study shows that better clinical efficacy can be achieved for tuberculosis in T4-6 segments using one-stage posterior-only approach by costotransverse debridement in combination with bone graft and internal fixation. The posterior surgical method cannot only effectively accomplish debridement, obtain satisfactory clinical results, but also well correct kyphotic deformity and maintain it.

Correlation of Acetabular Anteversion and Thoracic Kyphosis Postoperatively with Proximal Junctional Failure in Adult Spinal Deformity Fused to Pelvis.

OBJECTIVES: To investigate whether the immediate thoracic kyphosis (TK) and acetabular anteversion (AA) postoperatively are correlated with proximal junctional failure (PJF) in adult spinal deformity (ASD) patients underwent surgical treatment. METHODS: This is a retrospective study. Following institutional ethics approval, a total of 57 patients (49 Female, eight Male) with ASD underwent surgery fused to sacroiliac bone (S1, S2, or ilium) from March 2014 to January 2019 were included. All of those patients were followed up for at least 2 years. Demographic, radiographic and surgical data were recorded. The maximum range of flexion motion (F-ROM) and extension motion (E-ROM) actively of hip joints was measured and recorded at pre- and postoperation. The sum of F-ROM and E-ROM was defined as the range of hip motion (H-ROM). Receiver operating characteristic (ROC) curve analysis was used to obtain the cut off value of parameters for PJF. A Kaplan-Meier curve and log-rank test were used to analyze the differences in PJF-free survival. RESULTS: In all, 14 patients developed PJF during follow-up. Comparisons between patients with and without PJF showed significant differences in immediate TK (P < 0.001) and AA (P = 0.027) postoperatively. ROC curve analysis determined an optimal threshold of 13° for immediate AA postoperatively (sensitivity = 74.3%, specificity = 85.7%, area under the ROC curve [AUC] = 0.806, 95% CI [0.686-0.926]). Nineteen patients with post-AA ≤13° were assigned into the observational group, and 38 patients with post-AA >13° were being as the control group. Patients in the observational group had smaller H-ROM (P = 0.016) and F-ROM (P < 0.001), but much larger E-ROM (P < 0.001). There were 10 patients showing PJF in the observational group and four in the control group (10/9 vs 4/34, P < 0.001). PJF-free survival time significantly decreased in the observational group (P = 0.001, log-rank test). Furthermore, patients in the observational group had much larger TK (post-TK, P = 0.015). The optimal threshold for post-TK (sensitivity = 85.7%, specificity = 76.7%; AUC = 0.823, 95% CI [0.672-0.974]) was 28.1° after the ROC curve was analyzed. In the observational group, those patients with post-TK ≥28.1° had significantly higher incidence of PJF (9/2 vs 1/7, P < 0.001) than those with post-TK < 28.1°. Moreover, PJF-free survival time in those patients significantly decreased (P = 0.001, log-rank test). CONCLUSIONS: ASD patients with acetabular anteversion of ≤13° at early postoperation may suffer significantly restricted hip motion and much higher incidence of PJF during follow-up, moreover, in those patients, postoperative TK ≥28.1° would be a significant risk factor for PJF developing.

Effect of body mass index on bone mineral density is age-specific.

BACKGROUND AND AIMS: Obesity and osteoporosis are two important and growing public health problems worldwide. Body mass index (BMI) has been found to be inversely related to the risk of osteoporotic fracture. We aimed to assess the association of BMI with thoracic vertebral bone mineral density (BMD) measured from a quantitative computed tomography (QCT). METHODS AND RESULTS: We retrospectively evaluated the data from 15,758 consecutive patients (5675 females and 10,083 males) between age 20-90 years, who underwent Coronary Artery Calcium (CAC) scoring. Quantitative data analyses of thoracic trabecular BMD (mg/cm3) was performed with a phantom system or phantomless using validated software. The gender-specific subgroup was divided based on age (<45, 45-55, 55-65, >65 yrs in females; <40,40-60,>60 yrs in Males) and weight by BMI (kg/m2) as < 25 (normal or low weight), >25 - <30 (overweight) and >30 (obesity). Analysis of variance (ANOVA) and Scheffe's post hoc procedure tested the association of body weight/BMI on BMD. A significant positive association between the body weight and BMD existed in obese population in elder groups in both genders (p < 0.05). There was no significant difference in BMD in 40-60 years in men and <55 years in women with normal or low weight compared to overweight or obese cohorts. CONCLUSIONS: We concluded that the effect of weight on BMD is age-specific and the BMD should be monitored routinely with a cardiac CT scan in the senile population.

Effect of thoracic spinal cord injury on forelimb somatosensory evoked potential.

In this paper, we investigate the forelimbs somatosensory evoked potential (SSEP) signals, which are representative of the integrity of ascending sensory pathways and their stability as well as function, recorded from corresponding cortices, post thoracic spinal cord injury (SCI). We designed a series of distinctive transection SCI to investigate whether forelimbs SSEPs change after right T10 hemi-transection, T8 and T10 double hemi-transection and T8 complete transection in rat model of SCI. We used electrical stimuli to stimulate median nerves and recorded SSEPs from left and right somatosensory areas of both cortices. We monitored pre-injury baseline and verified changes in forelimbs SSEP signals on Days 4, 7, 14, and 21 post-injury. We previously characterized hindlimb SSEP changes for the abovementioned transection injuries. The focus of this article is to investigate the quality and quantity of changes that may occur in the forelimb somatosensory pathways post-thoracic transection SCI. It is important to test the stability of forelimb SSEPs following thoracic SCI because of their potential utility as a proxy baseline for the traumatic SCIs in clinical cases wherein there is no opportunity to gather baseline of the lower extremities. We observed that the forelimb SSEP amplitudes increased following thoracic SCI but gradually returned to the baseline. Despite changes found in the raw signals, statistical analysis found forelimb SSEP signals become stable relatively soon. In summary, though there are changes in value (with p > 0.05), they are not statistically significant. Therefore, the null hypothesis that the mean of the forelimb SSEP signals are the same across multiple days after injury onset cannot be rejected during the acute phase.

Large Lytic Defects Produce Kinematic Instability and Loss of Compressive Strength in Human Spines: An in Vitro Study.

BACKGROUND: In patients with spinal metastases, kinematic instability is postulated to be a predictor of pathologic vertebral fractures. However, the relationship between this kinematic instability and the loss of spinal strength remains unknown. METHODS: Twenty-four 3-level thoracic and lumbar segments from 8 cadaver spines from female donors aged 47 to 69 years were kinematically assessed in axial compression (180 N) and axial compression with a flexion or extension moment (7.5 Nm). Two patterns of lytic defects were mechanically simulated: (1) a vertebral body defect, corresponding to Taneichi model C (n = 13); and (2) the model-C defect plus destruction of the ipsilateral pedicle and facet joint, corresponding to Taneichi model E (n = 11). The kinematic response was retested, and compression strength was measured. Two-way repeated-measures analysis of variance was used to test the effect of each model on the kinematic response of the segment. Multivariable linear regression was used to test the association between the kinematic parameters and compressive strength of the segment. RESULTS: Under a flexion moment, and for both models C and E, the lesioned spines exhibited greater flexion range of motion (ROM) and axial translation than the control spines. Both models C and E caused lower extension ROM and greater axial, sagittal, and transverse translation under an extension moment compared with the control spines. Two-way repeated-measures analysis revealed that model E, compared with model C, caused significantly greater changes in extension and torsional ROM under an extension moment, and greater sagittal translation under a flexion moment. For both models C and E, greater differences in flexion ROM and sagittal translation under a flexion moment, and greater differences in extension ROM and in axial and transverse translation under an extension moment, were associated with lower compressive strength of the lesioned spines. CONCLUSIONS: Critical spinal lytic defects result in kinematic abnormalities and lower the compressive strength of the spine. CLINICAL RELEVANCE: This experimental study demonstrates that lytic foci degrade the kinematic stability and compressive strength of the spine. Understanding the mechanisms for this degradation will help to guide treatment decisions that address inferred instability and fracture risk in patients with metastatic spinal disease.

Biomechanical finite element analysis of vertebral column resection and posterior unilateral vertebral resection and reconstruction osteotomy.

BACKGROUND: Regarding the repair of vertebral compression fractures, there is a lack of adequate biomechanical verification as to whether only half of the vertebral body and the upper and lower intervertebral discs affect spinal biomechanics; there also remains debate as to the appropriate length of fixation. METHODS: A model of old vertebral compression fractures with kyphosis was established based on CT data. Vertebral column resection (VCR) and posterior unilateral vertebral resection and reconstruction (PUVCR) were performed at T12; long- and short-segment fixation methods were applied, and we analyzed biomechanical changes after surgery. RESULTS: Range of motion (ROM) decreased in all fixed models, with lumbar VCR decreasing the most and short posterior unilateral vertebral resection and reconstruction (SPUVCR) decreasing the least; in the long posterior unilateral vertebral resection and reconstruction (LPUVCR) model, the internal fixation system produced the maximum VMS stress of 213.25 mPa in a lateral bending motion and minimum stress of 40.22 mPa in a lateral bending motion in the SVCR. CONCLUSION: There was little difference in thoracolumbar ROM between PUVCR and VCR models, while thoracolumbar ROM was smaller in long-segment fixation than in short-segment fixation. In all models, the VMS was most significant at the screw-rod junction and greatest at the ribcage-vertebral body interface, partly explaining the high probability of internal fixation failure and prosthesis migration in these two positions.

Takotsubo syndrome triggered by change in position in a patient with thoracic vertebral fracture: A case report.

RATIONALE: Takotsubo syndrome (TTS) is characterized by recovery of wall motion abnormalities and acute left ventricular dysfunction, which are often caused by acute physical or emotional stressors. It is rarely reported that TTS can be precipitated by change in position in the patient in the operating room. We report a case of a patient with a thoracic vertebral fracture who presented with TTS precipitated by changing from a supine to a prone position before percutaneous kyphoplasty (PKP) under local anesthesia. PATIENT CONCERNS: A 76-year-old man who was diagnosed with a fracture in a thoracic vertebra was sent to the operating room to undergo PKP under local anesthesia. Approximately 5 minutes after changing from a supine to a prone position, which is necessary for PKP, the patient experienced chest pain, headache, and sweating. DIAGNOSIS: A fracture in a thoracic vertebra; TTS. INTERVENTIONS: As a result of 12-lead electrocardiography, echocardiography, left ventriculogram, and cardiac catheterization, the diagnosis of TTS was retained, and supportive therapy was initiated. OUTCOMES: Two hours later, the patient's symptoms mitigated significantly and the ST segment returned to baseline. Four days later, echocardiography showed normal systolic function without wall motion abnormalities and the patient returned to the orthopedics ward for further treatment. LESSONS: It is necessary for anesthetists to recognize TTS which is life-threatening during monitored anesthetic care (MAC). We highlight the importance of being alerted to the possibility of TTS when managing patients with thoracic vertebral fractures undergoing surgery under local anesthesia.

Density-Dependent Material and Failure Criteria Equations Highly Affect the Accuracy and Precision of QCT/FEA-Based Predictions of Osteoporotic Vertebral Fracture Properties.

About 700,000 vertebral fractures occur in the US as a result of bone loss. Quantitative computed tomography (QCT)-based finite element analysis (FEA) is a promising tool for fracture risk prediction that is becoming attractive in the clinical setting. The goals of this study were (1) to perform individual and pooled specimen optimization using inverse QCT/FEA modeling to obtain ash density-elastic modulus equations incorporating the whole vertebral body and accounting for all variables used during FE modeling, and (2) to determine the effect of material equations and failure criteria on the accuracy and precision of mechanical properties. Fifty-four (54) human vertebrae were used to optimize material equations based on experimental outcomes and, together with a previously proposed material equation, were implemented in our models using three different failure criteria to obtain fracture loads. Our robust QCT/FEA approach predicted 78% of the failure loads. Material equations resulted in poor accuracy in the predicted stiffness, yet yielded good precision and, more importantly, strong correlations with fracture loads. Both material and fracture criterion equations are equally important in estimating accurate and precise QCT/FEA predictions. Results suggest that both elastic modulus and fracture criterion equations should be validated against experimental outcomes to better explain the response of the tissue under various conditions.

Efficacy of Intraoperative Intervention Following Transcranial Motor-evoked Potentials Alert During Posterior Decompression and Fusion Surgery for Thoracic Ossification of the Posterior Longitudinal Ligament: A Prospective Multicenter Study of the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research.

STUDY DESIGN: Prospective, multicenter, observational study. OBJECTIVE: The aim of this study was to investigate the efficacy of intervention after an alert in intraoperative neurophysiological monitoring (IONM) using transcranial motor-evoked potentials (Tc-MEPs) during surgery for thoracic ossification of the posterior longitudinal ligament (T-OPLL). SUMMARY OF BACKGROUND DATA: T-OPLL is commonly treated with posterior decompression and fusion with instrumentation. IONM using Tc-MEPs during surgery reduces the risk of neurological complications. METHODS: The subjects were 79 patients with a Tc-MEP alert during posterior decompression and fusion surgery for T-OPLL. Preoperative muscle strength (manual muscle testing [MMT]), waveform derivation rate at the start of surgery (baseline), intraoperative waveform changes; and postoperative motor paralysis were examined. A reduction in MMT score of ≥1 on the day after surgery was classified as worsened postoperative motor deficit. An alert was defined as a decrease in Tc-MEP waveform amplitude of ≥70% from baseline. Alerts were recorded at key times during surgery. RESULTS: The patients (35 males, 44 females; age 54.6 years) had OPLL at T1-4 (n = 27, 34%), T5-8 (n = 50, 63%), and T9-12 (n = 16, 20%). The preoperative status included sensory deficit (n = 67, 85%), motor deficit (MMT ≤4) (n = 59, 75%), and nonambulatory (n = 26, 33%). At baseline, 76 cases (96%) had a detectable Tc-MEP waveform for at least one muscle, and the abductor hallucis had the highest rate of baseline waveform detection (n = 66, 84%). Tc-MEP alerts occurred during decompression (n = 47, 60%), exposure (n = 13, 16%), rodding (n = 5, 6%), pedicle screw insertion (n = 4, 5%), posture change (n = 4, 5%), dekyphosis (n = 2, 3%), and other procedures (n = 4, 5%). After intraoperative intervention, the rescue rate (no postoperative neurological deficit) was 57% (45/79), and rescue cases had a significantly better preoperative ambulatory status and a significantly higher baseline waveform derivation rate. CONCLUSION: These results show the efficacy of intraoperative intervention following a Tc-MEP alert for prevention of neurological deficit postoperatively.Level of Evidence: 2.

Diabetic thoracic radiculopathy: a case of a young woman with clinical improvement following immunotherapy.

Thoracic radiculopathy is a rare cause of thoracic-abdominal or abdominal pain in subjects with poorly controlled diabetes. We present a case of a young woman with type I diabetes and a severe abdominal pain in both lower quadrants. An extensive diagnostic gastroenterological and gynaecological workup did not disclose abnormalities. Electromyography revealed an initial polyneuropathy and significant neurogenic abnormalities in the T10-T12 paravertebral muscles. Following the hypothesis that the radiculopathy-related abdominal pain might have an immuno-mediated pathogenesis, the patient underwent a complex trial of immunotherapy, which was accompanied by a sustained improvement over months to full recovery. This report would support the hypothesis that immune-mediated mechanisms are still active even months after onset of symptoms.

Effects of massage therapy for patients with thoracic facet joint disorders: A protocol for systematic review and meta-analysis.

BACKGROUND: Thoracic facet joint disorder is a common thoracic disorder in clinic, inducing pain and discomfort at the dislocated thoracic vertebrae, radiating to pain of the neck and back. The incidence of thoracic facet joint disorder is higher than the facet disorder of the cervical and lumbar vertebrae. Therefore, an ideal strategy to relieve thoracic facet joint disorder is urgently needed. In recent years, massage therapy has been increasingly accepted by thoracic facet joint disorder patients due to its lower costs, fewer unwanted side effects and safety for clinical use. In this systematic review, we aim to evaluate the effectiveness and safety of massage therapy for patients with thoracic facet joint disorder. METHODS: We will search the following electronic databases for randomized controlled trials to evaluate the effectiveness of massage therapy in treating thoracic facet joint disorder: Wanfang and PubMed Database, CNKI, CENTRAL, CINAHL and EMBASE. Each database will be searched from inception to October 2020. The entire process will include study selection, data extraction, risk of bias assessment and meta-analyses. RESULTS: This proposed study will evaluate the effectiveness of massage therapy for patients with thoracic facet joint disorder. CONCLUSIONS: This proposed systematic review will evaluate the existing evidence on the effectiveness and safety of massage therapy for patients with thoracic facet joint disorder. DISSEMINATION AND ETHICS: The results of this review will be disseminated through peer-reviewed publication. Because all of the data used in this systematic review and meta-analysis has been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/XMEJD.

Thoracolumbar spine kinematics and injuries in frontal impacts with reclined occupants.

OBJECTIVE: Highly automated vehicles may permit alternative seating postures, which could alter occupant kinematics and challenge current restraint designs. One predicted posture is a reclined seated position. While the spine of upright occupants is subjected to flexion during frontal crashes, the orientation of reclined occupants tends to subject the spine to high compressive loads followed by high flexion loads. This study aims to investigate kinematics and mechanisms of loading in the thoracolumbar spine for a reclined seated posture through the use of postmortem human subjects (PMHS). METHODS: Frontal impact sled tests (50 kph delta-v) were conducted on five adult midsize male PMHS seated with the torso reclined to 50 degrees with respect to the vertical. The PMHS were seated on a semi-rigid seat and restrained by a seat-integrated three-point belt with dual lap-belt pretensioners and a shoulder-belt pretensioner with a 3 kN load-limiter. 3-D kinematic trajectories of five chosen vertebrae, and the pelvis were measured relative to the vehicle buck. Intervertebral pressure transducers were installed at three locations in the lumbar column to detect load timing. RESULTS: Three PMHS suffered fractures at L1. Combined compression and flexion of the thoracolumbar spine occurred in all tests, but the magnitude of peak flexion varied across the PMHS. During the PMHS' forward excursion, the pelvis rotated anteriorly in two tests and posteriorly in two tests (lap-belt submarining occurred in one). In one test, the pelvis mount interacted with the seat, but did not affect kinematics. CONCLUSIONS: Anterior rotation of the pelvis caused increased extension of the lumbar spine, which exacerbated lumbar compression in two of the PMHS; the one subject whose pelvis kinematic tracking was lost exhibited similar compression kinematics. Posterior rotation of the pelvis enabled lumbar flexion, which decreased lumbar compression, but lead to lap-belt submarining in one case. Lumbar kinematics for these reclined frontal impacts were sensitive to changes in initial posture of the spine (magnitude of lordosis or kyphosis) and pelvis (pitch angle). To our knowledge, this study is the first to analyze thoracolumbar kinematics and resulting injuries of a reclined seating posture using PMHS.

Comparison of Anterior and Posterior Decompressions in Treatment of Traumatic Thoracolumbar Spinal Fractures Complicated with Spinal Cord Injury.

BACKGROUND For patients with thoracolumbar spinal fractures complicated with spinal cord injury, timely surgery is the first choice. We compared the effects of anterior and posterior decompressions in treatment of these patients. MATERIAL AND METHODS A total of 80 male patients with traumatic thoracolumbar spinal fractures and spinal cord injury were prospectively selected and divided into 2 groups. The control group underwent posterior decompression and internal fixation and the observation group underwent real-time anterior decompression. RESULTS The observation group had longer operative time and length of postoperative hospital stay, larger intraoperative blood loss, remarkably greater immediate postoperative anterior height and middle column height of the fractured vertebrae, and a notably smaller Cobb's angle than in the control group. The total ASIA score was significantly higher in the observation group than in the control group immediately after surgery and at 6 months and 1 year after surgery. The maximal urine flow, maximal detrusor pressure, and bladder compliance were also evidently higher in the observation group than in the control group during 1 year of follow-up. Compared with the control group, the International Index of Erectile Function-5 (IIEF-5) score in the observation group was significantly higher at 3 months, 6 months, and 1 year after surgery. CONCLUSIONS Compared with the posterior approach, anterior decompression in patients with thoracolumbar spinal fractures complicated with spinal cord injury can effectually enhance the surgical efficiency, and restore the physiological anatomy of the fractured vertebrae, thereby improving patient quality of life.

Automated Gait Analysis to Assess Functional Recovery in Rodents with Peripheral Nerve or Spinal Cord Contusion Injury.

Peripheral and central nerve injuries are mostly studied in rodents, especially rats, given the fact that these animal models are both cost-effective and a lot of comparative data has been published in the literature. This includes a multitude of assessment methods to study functional recovery following nerve injury and repair. Besides evaluation of nerve regeneration by means of histology, electrophysiology, and other in vivo and in vitro assessment techniques, functional recovery is the most important criterion to determine the degree of neural regeneration. Automated gait analysis allows recording of a vast quantity of gait-related parameters such as Paw Print Area and Paw Swing Speed as well as measures of inter-limb coordination. Additionally, the method provides digital data of the rats' paws after neuronal damage and during nerve regeneration, adding to our understanding of how peripheral and central nervous injuries affect their locomotor behavior. Besides the predominantly used sciatic nerve injury model, other models of peripheral nerve injury such as the femoral nerve can be studied by means of this method. In addition to injuries of the peripheral nervous systems, lesions of the central nervous system, e.g., spinal cord contusion can be evaluated. Valid and reproducible data assessment is strongly dependent on meticulous adjustment of the hard- and software settings prior to data acquisition. Additionally, proper training of the experimental animals is of crucial importance. This work aims to illustrate the use of computerized automated gait analysis to assess functional recovery in different animal models of peripheral nerve injury as well as spinal cord contusion injury. It also emphasizes the method's limitations, e.g., evaluation of nerve regeneration in rats with sciatic nerve neurotmesis due to limited functional recovery. Therefore, this protocol is thought to help researchers interested in peripheral and central nervous injuries to assess functional recovery in rodent models.

Lumbar spine coordination during axial trunk rotation in adolescents with and without right thoracic idiopathic scoliosis.

Adolescent idiopathic scoliosis (AIS) is a complex deformity that often leads to loss of coordination and dynamic posture. However, there is a lack of understanding on inter-segmental coordination in AIS. The purpose of this study was to compare spinal range of motion (ROM), as well as the relations to coupling angles (CA) in the spinal region during trunk rotation, between AIS and control subjects. There were 14 subjects with right thoracic AIS and 18 control subjects who participated in the study. All subjects were asked to perform five repeated axial trunk rotations in standing while holding a bar. The outcome measures included ROM at the first thoracic spinous process (T1), the seventh thoracic spinous process (T7), the twelfth thoracic spinous process (T12), and the first sacrum spinous tubercle (S1) by the motion capture system. The CA in each spinal region (trunk, lumbar spine, and lower and upper thoraces) were analyzed while considering age and body mass index (BMI). The Cobb angle demonstrated positive moderate relationships with ROM at T7 (r = 0.62, p = 0.04) and the CA in the upper thorax (r = 0.69, p = 0.02) in the AIS group. There was no CA difference at the spinous processes between groups; however, the lumbar spine ROM significantly decreased in the AIS group (t = 2.40, p = 0.02). The BMI demonstrated moderate relationships on the lumbar spine (r = -0.67, p = 0.02) in the AIS group and the lower thorax (r = 0.59, p = 0.01) in the control group. The lumbar spine was significantly dissociated in the AIS group during trunk rotation, although the Cobb angle demonstrated positive relationships with ROM at T7. Collectively, the inter-segmental CA indicated that the AIS group compensated more independently to the right thoracic convexity. MINI ABSTRACT: The coordinated trunk rotations in the adolescent idiopathic scoliosis (AIS) group were compared with the control subjects. The lumbar spine motion was dissociated with the thorax in the AIS group and was negatively correlated with body mass index. Clinicians need to consider thorax convexity and dissociated lumbar motion for compensatory and rehabilitation strategies.