Opportunistic prediction of osteoporosis in patients with degenerative lumbar diseases: a simplified T12 vertebral bone quality approach

BACKGROUND

Osteoporosis is one of the risk factors for screw loosening after lumbar fusion. However, the probability of preoperative osteoporosis screening in patients with lumbar degenerative disease is low. Therefore, the aim of this study was to investigate whether a simplified vertebral bone quality (VBQ) score based on T12 T1-MRI could opportunistically predict osteoporosis in patients with degenerative lumbar spine diseases.

METHODS

We retrospectively analyzed cases treated for lumbar degenerative diseases at a single institution between August 2021 and June 2022. The patients were divided into three groups by the lowest T-score: osteoporosis group, osteopenia group, and normal bone mineral density (BMD) group. The signal intensity based on the T12 vertebral body divided by the signal intensity of the cerebrospinal fluid was calculated to obtain the simplified VBQ score, as well as the CT-based T12HU value and the traditional L1-4VBQ score. Various statistical analyses were used to compare VBQ, HU and DEXA, and the optimal T12VBQ threshold for predicting osteoporosis was obtained by plotting the receiver operating curve (ROC) analysis.

RESULTS

Total of 166 patients were included in this study. There was a statistically significant difference in T12VBQ scores between the three groups (p < 0.001). Pearson correlation showed that there was a moderate correlation between T12VBQ and T-score (r=-0.406, p < 0.001). The AUC value of T12VBQ, which distinguishes between normal and low BMD, was 0.756, and the optimal diagnostic threshold was 2.94. The AUC value of T12VBQ, which distinguishes osteoporosis from non-osteoporosis, was 0.634, and the optimal diagnostic threshold was 3.18.

CONCLUSION

T12VBQ can be used as an effective opportunistic screening method for osteoporosis in patients with lumbar degenerative diseases. It can be used as a supplement to the evaluation of DEXA and preoperative evaluation.

TRIAL REGISTRATION

retrospectively registered number:1502-009-644; retrospectively registered number date:27 oct 2022.

Severe hemothorax due to traumatic fracture of thoracic vertebra

BACKGROUND

Hemothorax occurs in approx. 0.4% of all chest injury patients, but hemothorax due to a thoracic vertebral fracture is rare.

CASE PRESENTATION

A 76-year-old Japanese man was transported to our hospital for right hemothorax due to a car accident. We performed emergency hemostasis surgery and tried to stop the bleeding by several methods, but it was difficult to control the bleeding because the bleeding point was an artery branch that runs in front of the vertebral body.

CONCLUSION

It is important to be aware that a fractured vertebra can damage the aorta's arterial branch and follow a severe course.

Sparganosis of a thoracic vertebra misdiagnosed as bone metastasis from lung cancer

Sparganosis is a rare parasitic infection caused by plerocercoid tapeworm larvae. We described a case of a 27-year-old man presenting with numbness in both legs and masses in the right lung and spine, initially thought to have spinal metastasis from lung cancer. However, after pathological and parasitological examinations, the patient was found to have spinal sparganosis, likely due to a history of consuming raw frogs. The patient was successfully treated with praziquantel, resulting in the recovery of muscle strength in his legs. This case highlights the importance of considering spinal sparganosis as a differential diagnosis in patients with spinal masses, especially those with a history of consuming raw or undercooked frogs. Accurate diagnosis and early treatment are crucial for managing this infection.

[Robot-assisted PVP for the treatment of osteoporotic fractures of the upper thoracic vertebra]

OBJECTIVE

To investigate the clinical effect of "Tianji" orthopedic robot-assisted percutaneous vertebro plasty(PVP) surgery in the treatment of upper thoracic osteoporotic fracture.

METHODS

A retrospective analysis was performed on 32 patients with upper thoracic osteoporotic fracture who underwent PVP surgery in Shenzhen Hospital of Traditional Chinese Medicine from August 2016 to June 2022. There were 8 males and 24 females, ranging in age from 58 to 90 years old, with a mean of (67.75±12.27) years old. Fifteen patients were treated with robot-assisted PVP surgery (robot group), including 3 males and 12 females, with an average age of (68.5±10.3) years. Fracture location:1 case of T2 fracture, 1 case of T3 fracture, 3 cases of T4 fracture, 3 cases of T5 fracture, and 7 cases of T6 fracture. The follow-up period ranged from 1.0 to 3.0 months, with a mean of (1.6±0.7) months. Seventeen patients underwent routine PVP surgery (conventional group), including 5 males and 12 females, with an average age of (66.8±11.6) years old. Fracture location:1 case of T1 fracture, 5 cases of T4 fracture, 2 cases of T5 fracture and 9 cases of T6 fracture. The follow-up period ranged from 0.5 to 4.0 months, with a mean of (1.5±0.6) months. Preoperative and postoperative visual analogue scale(VAS) and Oswestry disability index(ODI) scores were compared between the two groups, and the number of punctures, perspective times, operation time, intraoperative blood loss, bone cement distribution, bone cement leakage, and intraoperative radiation dose were compared between the two groups.

RESULTS

Number of punctures times, perspective times, operation time, intraoperative blood loss, bone cement distribution, bone cement leakage and intraoperative radiation dose in the robot group were all significantly better than those in the conventional group(P<0.05). VAS of 2.03±0.05 and ODI of (22.16±4.03) % in the robot group were significantly better than those of the robot group before surgery, which were (8.67±0.25) score and (79.40±7.72)%(t=100.869, P<0.001;t=25.456, P<0.001). VAS of 2.17±0.13 and ODI of (23.88±6.15)% in the conventional group were significantly better than those before surgery, which were (8.73±0.18) score and (80.01±7.59)%(t=121.816, P<0.001;t=23.691, P<0.001). There was no significant difference in VAS and ODI between the two groups after operation (t=-3.917, P=0.476;t=-0.922, P=0.364).

CONCLUSION

Robot-assisted PVP in the treatment of upper thoracic osteoporotic fractures can further improve surgical safety, reduce bone cement leakage, and achieve satisfactory clinical efficacy.

[Effectiveness of TiRobot-assisted and free-hand percutaneous kyphoplasty via pedicle of vertebra in treatment of osteoporotic vertebral compression fracture of thoracic vertebra]

Objective

To compare the effectiveness of TiRobot-assisted and C-arm X-ray fluoroscopy assisted percutaneous kyphoplasty (PKP) via pedicle of vertebra in the treatment of osteoporotic vertebral compression fracture (OVCF) of thoracic vertebrae.

Methods

The clinical data of 85 patients with OVCF of thoracic vertebrae who were admitted between January 2020 and March 2023 and met the selection criteria was retrospectively analyzed including 40 patients (50 vertebrae) undergoing PKP assisted by TiRobot (group A) and 45 patients (50 vertebrae) undergoing PKP assisted by C-arm X-ray fluoroscopy (group B). There was no significant difference in the comparison of baseline data such as gender, age, body mass index, bone mineral density T-value, fracture segment, trauma history, and preoperative numerical rating scale (NRS) score, Oswestry disability index (ODI), and Cobb angle of injured vertebra between the two groups ( P>0.05). The effectiveness evaluation indexes of the two groups, including the operation time, the volume of injected cement, the times of fluoroscopies, the length of hospital stay, and the occurrence of postoperative complications were collected and compared. Anteroposterior and lateral X-ray films and CT of the injured vertebra were reviewed at 1 day after operation to observe whether there was cement leakage and to evaluate the distribution of cement in the injured vertebra. Before and after operation, pain was assessed using the NRS score, dysfunction was assessed using the ODI, and vertebral height recovery was assessed by measuring the Cobb angle of the injured vertebrae by X-ray films.

Results

Both groups of patients successfully completed the operation, the operation time, the volume of injected cement, the times of fluoroscopies, and the length of hospital stay in group A were significantly less than those in group B ( P<0.05). The patients in two groups were followed up 4-12 months (mean, 9.6 months). Bone cement leakage occurred in 5 vertebrae in group A and 15 vertebrae in group B after operation, all of which leaked to the intervertebral space and around the vertebral body, and the patients had no obvious clinical symptoms. The difference of bone cement leakage between the two groups was significant ( P<0.05). No severe complication such as intraspinal leakage, infection, or vascular embolism was found in the two groups. At 1 day after operation, the distribution index of bone cement in group A was mostly grade Ⅴ, which was well dispersed; while in group B, it was mostly grade Ⅱ and grade Ⅴ; the difference of bone cement distribution index between the two groups was significant ( P<0.05). The NRS score, ODI, and Cobb angle of injured vertebra in both groups were significantly improved at 1 day after operation when compared with preoperative ones ( P<0.05). There was no significant difference in the difference of the above indexes between the two groups before and after operation ( P>0.05).

Conclusion

TiRobot-assisted unilateral PKP in the treatment of OVCF of thoracic vertebrae is safe and effective, which can reduce the X-ray transmission times during operation, shorten the operation time, reduce the volume of bone cement injection, and thus decrease incidence of bone cement leakage.

Pure uniportal video-assisted thoracic surgery for treating thoracic tuberculous spondylitis: an initial case series of seven patients

BACKGROUND

The development of thoracic surgical techniques has provided a new avenue for treating thoracic tuberculosis. Moreover, microscopic treatment of spinal tuberculosis has attracted increasing attention, as it affords good visual access and reduces trauma. Traditional thoracoscopic treatment of spinal tuberculosis usually requires 2-3 passages, accompanied by a corresponding number of incisions. With a large number of conventional thoracoscopic surgeries performed, improved resolution of the microscopic field of view, effective hemostasis of the peripheral vessels using the ultrasonic knife, and many reports in the literature, thoracic tuberculosis can now be treated microscopically by creating a single channel. The aim of this study was to explore the feasibility and surgical technique for thoracic tuberculous spondylitis treatment via debridement and bone graft fusion surgery employing pure uniportal video-assisted thoracic surgery (VATS), combined with posterior internal fixation.

METHODS

Seven patients with relatively complete documentation were included in this study. All patients underwent lesion removal and bone graft reconstruction via uniportal VATS with posterior internal fixation. The mean patient age was 39.6 years. Surgical duration, blood loss volume, postoperative recovery time, and thoracic kyphosis angle were recorded.

RESULTS

The surgeries were successful with no severe postoperative complications. All patients were followed-up, and no recurrence of tuberculosis was observed. Imaging data, including computed tomography scans, confirmed the complete removal of the lesions. Additionally, bone fusion at the graft site was successful, no loss of the thoracic kyphosis angle was noted postoperatively, and the thoracic kyphosis angle improved.

CONCLUSIONS

Pure uniportal VATS yields satisfactory results and inflicts less trauma than previous surgical techniques. This technique also offers a reference value for treating thoracic tuberculous spondylitis.

[Intraoperative ultrasound assisted circumferential decompression for multilevel ossification of the posterior longitudinal ligament in thoracic vertebrae]

OBJECTIVE

To analyze the effect of short-segment circumferential decompression and the nerve function improvement in 30 cases of multilevel thoracic OPLL assisted by intraoperative ultrasound.

METHODS

A total of 30 patients with multilevel thoracic OPLL from January 2016 to January 2021 were enrolled, all of whom were located by intraoperative ultrasound and underwent circumferential decompression. There were 14 males and 16 females, with an average age of (49.3±11.4) years. The initial symptoms were mainly numbness and weakness of lower limbs (83.3%), and the mean duration of symptoms was (33.9±42.9) months (1-168 months). Neurological function was assessed by the Modified Japanese Orthopedic Association (mJOA) score (0-11) preoperative and at the last follow-up, in which the rate of neurological improvement was calculated by the Harabayashi method. The patients were divided into excellent improved group and poor improved group according to the improvement of neurological function. The age, body mass index (BMI), duration of symptoms, operation time, blood loss, mJOA score, surgical level, and cerebrospinal fluid leakage of the two groups were collected and analyzed for statistical differences. The factors influencing the improvement of neurological function were analyzed by univariate and multivariate Logisitic regression analysis.

RESULTS

The mean operation time was 137.4±33.8 (56-190) min, and the mean blood loss was (653.7±534.2) mL (200－3 000 mL). The preoperative mJOA score was 6.0±2.1 (2－9), and the last follow-up mJOA score was 7.6±1.9 (4－11), which was significantly improved in all the patients (P < 0.001). The average improvement rate of neurological function was 38.1%±24.4% (14.3%－100%), including 75%－100% in 4 cases, 50%－74% in 3 cases, 25%－49% improved in 14 cases, and 0%－24% in 9 cases. There was significant difference in intraoperative blood loss between the excellent improved group and the poor improved group (P=0.047). Intraoperative blood loss was also an independent risk factor in regression analysis of neurological improvement.

CONCLUSION

Thoracic circumferential decompression assisted with intraoperative ultrasound can significantly improve the neurological function of patients with multilevel OPLL and achieve good efficacy. The improvement rate of nerve function can be improved effectively by controlling intraoperative blood loss.

The Role of Classifications and Measurements of Kyphotic Angle in the Treatment Methods of Upper and Middle Thoracic Vertebral Fractures after Trauma

BACKGROUND AND AIM

Thoracic fractures can lead to death and disability. This retrospective study aimed to evaluate cases of upper and middle thoracic vertebral fractures due to trauma that had been treated, to determine the fracture type and treatment method according to age, sex, cause of injury, neurological status, fracture level, kyphotic angles, and classification methods and to discuss the results regarding that reported in the literature.

PATIENTS AND METHODS

This study included 238 patients who were evaluated for post-traumatic upper and middle thoracic vertebral fractures between January 2012 and December 2020. We classified each patient according to the Dennis, TLICS, ATLICS, and ASIA classifications using neurological examination, radiography, computed tomography, and magnetic resonance imaging. We statistically evaluated the data obtained.

RESULTS

Fifty-five percent of total patients were male. The average age was 51.11. Traffic accidents were the most common causes of trauma, with 67.2%. T8 was most affected. The ASIA classification, the Dennis, TLICS, and ATLICS classifications showed a significant increase in the severity of neurological deficits as the fracture scores increased (p < 0.001). We observed that the increase in the preoperative kyphotic angle caused an increase in the number of deficits according to the classifications (p < 0.001).

CONCLUSION

The ATLICS classification yielded more accurate results than that of the other classifications. In addition, the kyphotic angle was evaluated for upper and middle thoracic fractures, and we concluded it is important in surgical decision making.

Comparison of DNA preservation between ribs and vertebrae

The choice of skeletal element types and their intra-bone parts is important because of differences in DNA preservation, and this must be considered when sampling bones for DNA testing. When incomplete skeletons are found, ribs and vertebrae have been shown to be the most suitable for genetic identification of bones from the torso. This study compares the preservation of DNA between 12th thoracic vertebrae and first ribs to determine which bone type is more suitable for genetic typing. The study analyzed 35 12th thoracic vertebrae and 29 first ribs from one mass grave from the Second World War with commingled skeletal remains excavated. Bone DNA preservation was estimated by measuring nuclear DNA concentration and its degradation and through short tandem repeat (STR) typing success. Previous studies performed on aged skeletal remains have shown that the DNA content of the first ribs and 12th thoracic vertebrae has high intra-bone variability, and this was considered when sampling the bones. After full demineralization extraction, the PowerQuant System (Promega) was used to measure the quantity and quality of DNA, and the GlobalFiler kit (Applied Biosystems) was used for STR typing. The results showed that DNA yield and degradation and STR typing success exhibited no statistically significant difference between first ribs and 12th thoracic vertebrae, and there was no intra-individual difference when comparing only paired bones from the same individuals. Consequently, with intra-bone DNA variability considered, the first ribs or the 12th thoracic vertebrae can be selected when sampling to genetically identify the skeletal remains of highly degraded torsos. HIGHLIGHTS: The first ribs and thoracic vertebrae are the most suitable bones for sampling from the torso. The proximal part of first rib and posterior vertebral column of the 12th thoracic vertebrae yielded the most DNA. The first ribs were compared with the 12th thoracic vertebrae, and the sampling process considered intra-bone DNA variability. The quality and quantity of nuclear DNA and success of STR typing were measured. The first ribs yielded the same DNA yields as well as STR typing success as the 12th thoracic vertebrae. When only the torso is present, it is not of high importance whether the first ribs or the 12th thoracic vertebrae are collected.

Foot drop as the initial symptom caused by thoracic disc herniation

BACKGROUND

Foot drop is a syndrome resulting from weakness or paralysis of the tibialis anterior muscle. Some patients with thoracic disc herniation seek medical help complain of foot drop as the initial symptom. The study investigated the clinical characteristics of these patients and clarified the clinical efficacy after treatment.

METHODS

A total of 13 patients with foot drop as the initial symptom arising from thoracic disc herniation were collected from January 2015 to December 2020. The average follow-up period was 20.5 months. We recorded neurological functions, the tibialis anterior muscle strength, Japanese Orthopedic Association score (JOA), location of the lesion, and occupation rate of herniation in the spinal canal preoperatively and at the final follow-up.

RESULTS

None pathological reflex was found in the patients. Surgical treatment was performed in 12 of the 13 patients, and tibialis anterior functional recovery was observed in 83.4% (10/12) of the cases, with an average recovery rate of 52.8 ± 18.5%. The mean JOA score increased from 6.8 ± 1.9 points preoperatively to 8.9 ± 1.3 points postoperatively (p < 0.05), achieving a mean recovery rate of 52.3 ± 13.1%. The MRI showed the conus medullaris was obviously compressed at the level of T11-L1, and the occupation rate of herniation was more than 40% in all patients, with an average of 65.4 ± 16.3%. CT indicated that 84.6% of the cases had calcification in intervertebral discs.

CONCLUSION

Foot drop can be the initial symptom caused by thoracic disc herniation at the T11-L1 level, especially for the calcified disc herniation. A satisfactory recovery rate can be achieved by surgical decompression with fixation.

Thoracic vertebra interbody fusion surgery with robotic assisted system in a swine model

Minimally invasive procedures have been increasing in spine surgery, and interest in robotic systems has inclined. In this study, we aimed to evaluate feasibility of a robotic-assisted thoracic spine interbody fusion in a swine model. Neurosurgeons performed the surgical procedures with robotic surgery certificates on the Da Vinci Xi Surgical System. Surgical approaches were applied using four ports while the swine was in the left lateral position. The surgical procedure was accomplished in 70 min including positioning and preparation of robotic system (20 min), placement of ports and thoracic dissection and confirmation of level with the C-arm system (10 min), discectomy and cage insertion (15 min), control of cage position via the C-arm system and closure (10 min). This study showed the anterior thoracic approach with robotic surgery is safe and feasible with providing a wide working area and high image quality.

Intra-bone nuclear DNA variability and STR typing success in Second World War 12th thoracic vertebrae

Bones are an important source of DNA for identification in forensic medicine, especially when the remains are skeletonized, which is the case when dealing with victims of the Second World War. Often the amount of bone available for sampling is limited, and therefore it is crucial to sample the bone segment with the highest adequate DNA quantity for identification. Studies performed on all representative skeletal element types of the human body showed that the amount of DNA obtained from different skeletal elements of different body regions varies greatly. When bones from torso were analyzed, thoracic vertebrae outperformed other vertebrae (cervical and lumbar) and, alongside the first ribs, were among the most appropriate bone elements for identification purposes. It was also shown that the quantity of DNA varies significantly within a single bone type. This study focused on exploring intra-bone DNA variability between five parts of 12th thoracic vertebrae (laminae + spinous process, pedicles + transverse processes, and corpus right, left, and middle). The research was based on the theory that the distribution of body weight and consequently bone remodeling, as well as the ratio between cancellous and cortical bone, contribute to different quantities of DNA in different parts of vertebra sampled. The vertebrae were cleaned and cut into five parts, and each part was completely ground to obtain homogenous bone powder. Half a gram of powder from each part was decalcified using a full demineralization extraction method. The DNA was purified in a Biorobot EZ1 machine (Qiagen). DNA quantity and quality were determined using the PowerQuant System (Promega) and autosomal STR typing success using the GlobalFiler Amplification Kit (Applied Biosystems). Thirty-five 12th thoracic vertebrae were sampled from a single Second World War mass grave. The best results with the highest DNA quantity were found in laminae and the spinous process, and among them all vertebrae analyzed yielded full STR profiles except three, where only a few dropouts occurred. The second-ranked bone part was the pedicles and transverse processes. The comparison of DNA degradation in the vertebral segments analyzed does not show statistically significant differences. Considering our research, when only the torso is available for identification, the 12th thoracic vertebra should be collected and the vertebral arch should be sampled for genetic analyses.

Functional anatomy and adaptation of the third to sixth thoracic vertebrae in primates using three-dimensional geometric morphometrics

The morphology of the cranial thoracic vertebrae has long been neglected in the study of primate skeletal functional morphology. This study explored the characteristics of the third to sixth thoracic vertebrae among various positional behavioural primates. A total of 67 skeletal samples from four species of hominoids, four of cercopithecoids, and two of platyrrhines were used. Computed tomography images of the thoracic vertebrae were converted to a three-dimensional (3D) bone surface, and 104 landmarks were obtained on the 3D surface. For size-independent shape analysis, the vertebrae were scaled to the same centroid size, and the normalised landmarks were registered using the generalised Procrustes method. Principle components of shape variation among samples were clarified using the variance-covariance matrix of the Procrustes residuals. The present study revealed that the transverse processes were more dorsally positioned in hominoids compared to non-hominoids. The results showed that not only a dorsolaterally oriented but also a dorsally positioned transverse process in relation to the vertebral arch contribute to the greater dorsal depth in hominoids than in monkeys. The thoracic vertebrae of Ateles and Nasalis show relatively dorsoventrally low and craniocaudally long vertebrae with craniocaudally long zygapophyses and craniocaudally long base/short tip of the caudally oriented spinous process, accompanied by a laterally oriented and craniocaudally long base of the transverse process. Despite being phylogenetically separated, the vertebral features of Ateles (suspensory platyrrhine with its prehensile tail's aid) are similar to those of Nasalis (arboreal quadrupedal/jumping/arm-swing colobine). The morphology of the third to sixth thoracic vertebrae tends to reflect the functional adaptation in relation to positional behaviour rather than the phylogenetic characteristics of hominoids, cercopithecoids, and platyrrhines.

Is it an asymptomatic tracheal injury or misdiagnosis in treatment of vertebral fracture: A case report

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Pedicle screws are durable and safe tools that are frequently used in the treatment of vertebral fractures.

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The most important complications of the use of pedicle screws are vascular injuries, internal organ injuries and spinal cord injuries.

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Imaging methods, navigation systems, and cannulated pedicle screws should be used more frequently to reduce visceral organ injuries in the surgery of thoracic vertebral fractures.

Introduction

Pedicle screws are durable and safe instruments frequently used to treat vertebra injuries and deformities. There is also a possibility of medulla spinalis and visceral organ injury when the pedicle screws are delivered in unsuitable positions or dimensions. In this case, the authors want to draw attention to one of the visceral organ injuries during the thoracic pedicle screw placement.

Presentation of case

A 31 years old man underwent posterior instrumentation and fusion for T4 vertebra fractures. The patient was not symptomatic in the postoperative period. Tracheal pressure was observed at the 3rd thoracic vertebra level on the second day after the operation. No complications were encountered in the 3-year follow-up of the patient, who did not accept a second surgery recommended for screw replacement.

Discussion

During surgery for thoracic vertebral fractures, the shoulder joint makes it difficult to imagine as the shoulder bones enter the field of view. Therefore, the number of misplaced screws increases. Moreover, it increases the risk of internal organ injury.

Conclusion

The use of navigation systems or cannulated pedicle screws to treat thoracic vertebral fractures reduces internal organ injuries.

A finite element analysis on comparing the stability of different posterior fixation methods for thoracic total en bloc spondylectomy

Objective

To compare the spinal stability with different fixation methods after thoracic TES using finite element analysis

Methods

The spinal finite element model was established from a healthy volunteer, and the validity was verified. The models of T8 thoracic total en bloc spondylectomy (TES) with and without artificial vertebral body were established combination with different fixation methods: the first was long segment fixation with fixed segments T5–7, T9–11; the second was short segment fixation with fixed segments T6–7, T9–10; the third was modified short segment with a pair of vertebral body screws on T7 and T9 added on the basis of short segment fixation. The motions of each model in standing state were simulated in software. The range of motion (ROM) and internal fixation stress changes were analyzed.

Results

When anterior support was effective, the three fixation methods could effectively maintain the stability of the spine. However, when anterior support failed, the ROM of the long segment fixation group and the short segment fixation group in the flexion-extension directions was significantly higher than that of when the anterior support existed, while the modified short segment fixation group had no significant changes. Meanwhile, the stress of internal fixation in the long segment fixation group and the short segment fixation group were greatly increased. However, there were no significant changes in modified short segment fixation group.

Conclusion

After TES, the presence of the thoracic cage gives partial anterior stabilization. When the anterior support failed, the modified short segment fixation method can provide better stability.

Design, application, and evaluation of a novel method for determining optimal trajectory of thoracic pedicle screws

Background

This is an experimental study performed on 15 adult cadavers. In this cadaveric study, we designed and evaluated a novel methodology for determining the optimal trajectory for the placement of thoracic pedicle screws. The accuracy of thoracic pedicle screw placement is critical to the spinal surgery. The concept, implement method, and significance of the optimal thoracic pedicle trajectory have not been reported.

Methods

The experimental study was performed on 15 adult cadavers. The Mimics software was used to design optimal trajectory through the pedicle central axis. Using three-dimensional (3D) printing, a navigation module with a locating facet and a stabilizing facet was developed. The thoracic pedicle screws were inserted with the help of the navigation module. The three-dimensional coordinates for the entry and the exit points of the screws were compared between the planned trajectories and the postoperative trajectories. The differences in coordinates were analyzed to evaluate the precision of the screw placement.

Results

The trajectories through the pedicle central axis showed an excellent symmetry between the single segments and for all thoracic vertebrae. Out of a total of 358 screws that were inserted, 15 (4.2%) screws breached the pedicle cortex with a breach distance of <2 mm. The qualifying rate was 98.6% (353/358) for the entry point precision of ≥3.2 mm, and 98.9% (354/358) for the exit point precision of ≥6.4 mm. In comparison to the designed qualified rate of 100% (358/358), the χ² was 3.22 and 2.26, respectively (P>0.05).

Conclusions

The optimal trajectory was obtained through the pedicle central axis, which significantly reduced the risk of cortex breach. A high degree of precision was obtained for the entry and the exit points of the screws when the postoperative trajectory was compared with the designed trajectory.

Morphometric analysis of the costal facet of the thoracic vertebrae

Various studies have examined morphometric features of the vertebrae to understand the functional aspects of the spine. Geometric analysis of vertebral zygapophyseal facets has also been related to functional and clinical aspects of the spine, but no quantitative investigation of the costotransverse joint facet is found in the literature. The costal facet geometry may partly determine the mechanical interaction between the rib cage and spine for trunk stabilization during functional tasks and during breathing. Therefore, the present study proposes a method for estimating the 3D geometric features of the costal facets of the first 10 thoracic vertebrae (Th1-Th10). Series of landmarks (95 ± 43) were placed on 258 costal facets from a sample of 14 asymptomatic individuals to determine their 3D location and orientation. The relative location of the costal facet was used to investigate symmetry and asymmetry components of the overall vertebrae shape variation among thoracic levels using 3D geometric morphometric methods. Results showed significant variation in sagittal orientation (inclination angle) between levels with a gradual cephalic orientation in the lower levels. No significant difference was observed on transverse orientation (declination angle). The shape of the costal facet was flatter at Th1 and from Th5 to Th10 and more concave from Th2 to Th4. An average difference of 7° between right and left facet orientation in both sagittal and transverse plane was demonstrated. Asymmetry of costal facet relative location was also detected and significantly influenced by the thoracic level. Nevertheless, location and orientation of the costal facets seem to be independent features of vertebrae morphology.

Primary bone lymphoma of the thoracic vertebra in a patient with metastatic lung cancer

We present a rare case of primary diffuse large B-cell lymphoma of the thoracic vertebra in a patient with metastatic lung cancer.

Thoracic vertebrae fracture: Is it an indicator of abdominal injury?

PURPOSE

Traumatic vertebral fracture accounts for 10-15% of trauma related admissions. While the correlation between lumbar vertebral fractures and abdominal injuries is well established, the relationship between thoracic vertebral fractures (TVF) and abdominal injuries is comparatively less well elucidated. Using a large national trauma database, we aimed to examine the incidence and severity of associated abdominal injuries in blunt trauma patients suffering from TVF.

METHODS

A retrospective cohort study using the Israeli National Trauma Registry was conducted. Patients with thoracic vertebrae spine fractures following blunt mechanisms of trauma between 1997 and 2018 were examined, comparing the incidence and severity of associated intraabdominal organs injuries with and without TVF. Demographics and outcomes between the two cohorts were compared.

RESULTS

From 362,924 blunt trauma patients, 4967 (1.37%) had isolated TVF. Mean age was 49.8 years and 61.9% were males. The most common mechanism of injury was fall following by MVC. The patients with TVF had significantly higher rates of increased ISS score (ISS > 16, 28.45% vs. 10.42%, p < 0.001) and higher mortality rate (3.5% vs. 2%, p < 0.0001). Patients with TVF had 2-3 times more intraabdominal organ injuries (p < 0.001). The most commonly injured organ was spleen (3.28%); followed by liver (2.64%) and kidney (1.47%). An analysis of non-isolated thoracic spine fractures showed same distribution in age, ISS, mechanisms, patterns of intra-abdominal injury, mortality rate and laparotomy rate.

CONCLUSION

Clinicians should have an elevated suspicion for intra-abdominal injuries when a thoracic spine fracture is identified, which may necessitate further evaluation.

[Clinical application of vertebral arch-transverse pathway in pedicle screw implantation]

Objective

To investigate the safety and effectiveness of pedicle screw implantation via vertebral arch-transverse pathway in clinical application by a prospective randomized controlled trial.

Methods

Twenty-four patients who were admitted between May 2015 and June 2017 and met the selection criteria for thoracic pedicle screw fixation were included in the study. According to the random number table method, they were divided into the trial group (screw implantation via vertebral arch-transverse pathway) and the control group (traditional screw implantation technology), with 12 patients in each group. There was no significant difference between the two groups in age, gender, cause of injury, injured segment, and the interval between injury and operation (P>0.05). The time of screw implantation was recorded and compared between the two groups. The acceptable rate of screw implantation and the penetration rate of pedicle wall were calculated after operation.

Results

The time of screw implantation of trial group was (5.08±1.74) minutes, which was significantly shorter than that of control group [(5.92±1.66) minutes], and the difference was significant (t=4.258, P=0.023). Patients in both groups were followed up 1-2 years, with an average of 1.5 years. During the follow-up, no failure of internal fixation occurred. At 1 week after operation, the screw implantation in trial group was rated as gradeⅠin 54 screws, gradeⅡ in 3 screws, and grade Ⅲ in 2 screws, with the acceptable rate of 93.61%. The screw implantation in control group was rated as gradeⅠin 40 screws, grade Ⅱin 10 screws, grade Ⅲ in 8 screws, and grade Ⅳ in 1 screw, with the acceptable rate of 84.75%. There was significant difference in the acceptable rate of screw implantation between the two groups (χ²=3.875, P=0.037). The penetration rate of pedicle wall in trial group was 8.47% (5/59), which was significantly lower than that in the control group [32.20% (19/59); χ²=4.125, P=0.021].

Conclusion

Compared with the traditional technique, the pedicle screw implantation via vertebral arch-transverse pathway can obtain a good position of the screw canal with higher accuracy and simpler operation.

Bilateral thoracic paravertebral block combined with general anesthesia vs. general anesthesia for patients undergoing off-pump coronary artery bypass grafting: a feasibility study

BACKGROUND

Whether thoracic paravertebral block (PVB) is useful in patients undergoing off-pump coronary artery bypass grafting (OPCABG) remains unknown. This study aimed to investigate the feasibility of bilateral PVB combined with general anesthesia (GA) in patients undergoing OPCABG.

METHODS

This feasibility study assessed 60 patients scheduled for OPCABG at the Qingdao Municipal Hospital in 2016-2017. Patients were randomly assigned to receive nerve stimulator-guided bilateral PVB combined with GA (PVB + GA) or GA alone (n = 30/group). Patients were asked to rate rest and cough pain hourly after the surgery. The primary endpoint was the visual analogue scale (VAS) pain score within 48 h postoperatively. Secondary endpoints were rescue analgesia and morphine consumption, fentanyl dose within 48 h postoperatively, as well as operative time, time to extubation, intensive care unit (ICU) stay, hospital stay and other postoperative adverse events.

RESULTS

Both rest and cough pains were lower in the PVB + GA group at 12, 24, 36, and 48 h after surgery compared with the GA group. There were fewer patients who needed rescue analgesia in the PVB + GA group at 12 and 24 h than in the GA group. Morphine consumptions at 24 and 48 h were lower in the PVB + GA group compared with the GA group. Time to extubation (P = 0.035) and ICU stay (P = 0.028) were shorter in the PVB + GA group compared with the GA group. AEs showed no differences between the two groups.

CONCLUSIONS

Nerve stimulator-guided bilateral thoracic PVB combined with GA in OPCABG is associated with a reduced rescue analgesia and morphine consumption, compared to GA.

Thoracic cryptococcal osteomyelitis mimicking tuberculosis: A case report

Background:

Isolated cryptococcal osteomyelitis of the spine is extremely uncommon; there have been only seven cases identified in literature. The majority were originally misdiagnosed as tuberculosis. Here, we present a patient with cryptococcal osteomyelitis of the thoracic spine with associated fungal retinal deposits.

Case Description:

A 45-year-old, type II diabetic female presented with a 5-month history of severe back pain. Her magnetic resonance imaging (MRI) revealed osteomyelitis involving the T4 vertebral body with epidural and prevertebral extension; notably, the intervertebral disc spaces were not involved. Although the fine-needle aspiration cytologic examination was inconclusive, the patient was empirically placed on antitubercular drug therapy. One month later, she became fully paraplegic. The MRI now demonstrated osteolytic lesions involving the T4 vertebral body with cord compression. She underwent biopsy of the T4 vertebral body and a transfacet T4 decompression with T2-T6 pedicle screw fixation. Culture and histopathological examinations both documented a cryptococcal infection, and she was placed on appropriate antifungal therapy. Notably, 3 weeks after surgery, she developed a sudden loss of vision loss due to retinal fungal endophthalmitis. She recovered vision in one eye after the administration of intravitreal voriconazole but lost vision in the other eye despite a vitrectomy. Over the next 8 months, she gradually recovered with motor function of 4/5 in both lower extremities without evidence of recurrent disease.

Conclusion:

Cryptococcal infection should be among the differential diagnostic considerations for patients with vertebral osteomyelitis. Notably, diagnostic delay can lead to devastating neurological deficits and involvement of other organ systems.

Aortic Injury by Thoracic Pedicle Screw. When Is Aortic Repair Required? Literature Review and Three New Cases

PURPOSE

Aortic injury by pedicle screw is rare but can cause serious complications. It has not been clearly determined when aortic repair is necessary in cases of screw impingement without perforation of the aortic wall. In this article, we review the treatment and clinical course of pedicle screw aortic impingement and attempt to clarify this issue.

METHODS

Cases of aortic injury during thoracic screw procedures were found using a MEDLINE search and analyzed together with 3 new cases that we present.

RESULTS

Nineteen cases collected from the literature and 3 new cases were included in the study. In 7 of the cases, aortic impingement by the pedicle screw was detected during postoperative follow-up (day 1) radiologic examinations. In the other cases, time to presentation of aortic impingement ranged between 2 weeks and 60 months after fixation. The main indications for thoracic spinal fixation were post-traumatic vertebral fracture and kyphoscoliosis/scoliosis. Repair of the aortic damage ranged from primary repair to stent and tube graft placement by the thoracic endovascular aortic repair method.

CONCLUSIONS

In cases in which the screw impinges less than 5 mm into the aortic wall, hardware revision without aortic repair may be sufficient if recognized early and there are no sign of aortic leakage in vascular imaging. However, cases with more than 5 mm of screw impingement should undergo aortic repair first, even in the absence of aortic leakage, following by screw revision.

Biomechanical Evaluation of an Anterior Upper Thoracic Plate Fixation System: An In Vitro Human Cadaveric Study

OBJECTIVE

This study aimed to evaluate the biomechanical characteristics of the anterior upper thoracic plate fixation system (AUTP).

METHODS

Twelve specimens were divided into 2 groups: the AUTP group and the anterior cervical locking plate (ACLP) group. Bone mineral density was assessed in all specimens. The specimens were loaded with pure bending moments of ±4 Nm to move toward extension/flexion, right/left lateral tilt, and right/left axial rotation. Each specimen was tested in 3 load cycles under 3 conditions (native, destabilized, and torsion). The tightening moments were assessed in every screw using a torsion meter.

RESULTS

The tightening moment of the AUTP screws was more pronounced than the ACLP (P < 0.05). Significant decreases after stabilization with the AUTP compared with the native situation were observed in the AUTP group (P < 0.05). In terms of the direction of lateral tilt and torsion, the neutral zone increased significantly after stabilization with the AUTP compared with the native situation (P < 0.05).

CONCLUSIONS

The AUTP was shown to provide more rigidity to the destabilized spine than the ACLP.

[A clinic analysis of thoracolumbar vertebral fracture cascade]

Objective: To observe the clinical characteristics of thoracolumbar vertebral fracture cascade, analyze the relationship between the baseline fractures and the subsequent fractures and compare the distribution differences of subsequent fractures following vertebral augmentation or non-operation. Methods: From July 2012 to August 2016, 1 363 patients admitted to the First Affiliated Hospital of Soochow University with vertebral augmentation for the treatment of vertebral fractures were retrospectively analyzed.There were 190 cases of vertebral fracture cascade, 160 females and 30 males, with an average age of (74±9) years.The location and sequence of all vertebral fractures were recorded.The relationships between the baseline and the subsequent fractures were analyzed.According to different treatment on the baseline vertebral fractures, 190 cases were divided into vertebral augmentation group and non-operation group.The distribution differences of the subsequent fractures following vertebral augmentation and non-operation were compared with chi-square test. Results: Vertebral fracture cascade mainly located in the thoracolumbar spine T(11)-L(2) with an incidence of 52.0%.According to the direction of fracture development, the fracture cascade could be divided into up, down, centrifugation and concentration, and the incidence was 39.8%, 39.2%, 8.4% and 12.6%, respectively.The closer the vertebral body to the baseline fractures, the subsequent fractures incidence was higher.For distance with zero, one, two, three and four vertebrae, the incidence of subsequent vertebral fractures was 36.5%, 26.2%, 15.2%, 11.5% and 3.7%, respectively.A linear relationship was found between the subsequent fractures and the baseline fractures with a correlation coefficient of 0.90.The distribution difference of subsequent fractures between vertebral augmentation and non-operation group was not significant (χ(2)=17.16, P>0.05). Conclusions: The main directions of vertebral fracture cascade is up or down spiral development.The closer the vertebral body to the baseline fractures, the subsequent fractures incidence is higher.Vertebral augmentation doesn't affect the distribution of subsequent fractures.

Rosai-dorfman disease in thoracic spine: a rare case of compression fracture

Sinus histiocytosis with massive lymphadenopathy known as Rosai-Dorfman disease is characterized by painless bilateral cervical lymphadenopathy. Extranodal manifestations are uncommon and spinal involvement is rare. A 15-year-old man presented with intermittent midthoracic back pain only. He had no specific findings on neurologic examinations, hematologic and biochemical laboratory tests. Radiological examination of thoracic spine revealed collapse of T6 vertebrae with thoracic kyphosis and osteolytic lesion of T12 vertebra body. He underwent a removal of bone tumor, anterior reconstruction with mesh and pedicle screw fixation via posterior approach for pathologic confirmation and stabilization. Histopathologic study of the lesion revealed focal infiltration of large histiocytes showing emperipolesis. Immunochemistry stain of histiocytes was positive for CD68 and S-100 but negative for CD1a. This report presents a rare case and literature review of extranodal Rosai-dorfman disease in thoracic spine.