A study on the vertebral column of the dice snake Natrix tessellata (Serpentes, Natricidae) from Denizli (western Anatolia, Turkey)

The vertebral anatomy of snakes has attracted the attention of researchers for decades and numerous studies have been made for extinct and extant species. The present study investigated the morphological variations in vertebral structure among different vertebral regions in the dice snake Natrix tessellata, and provides a detailed anatomical and microstructural description of the vertebral column. Vertebrae were analyzed and compared using x-ray imaging, scanning electron microscopy, micro-computed tomography, and histological techniques. The vertebral column of N. tessellata is divided into three regions: precloacal, cloacal, and caudal. Unlike in many other tetrapods and snakes, the atlas of N. tessellata does not form a complete ring. It has a flat and roughly trilobate shape with a prominent middle lobe. The axis has two hypapophyses. The anterior precloacal region of the vertebral column has longer and more paddle-shaped hypapophyses, distinguishing it from the posterior and mid-trunk vertebrae. The anterior cloacal vertebrae have a short hypapophysis rather than a hemal keel, and the lymphapophysis extends outward, curving slightly. The cotyle and condyle of the caudal vertebrae exhibited a closer resemblance to a rounded shape, while the pleurapophysis extended ventrolaterally and curved ventrally near its distal end. Paired hemapophyses were present at the posterior-most point of the centrum instead of a hypapophysis. In light of previous fossil findings, our anatomical comparison of the vertebral and transverse processes indicates that the extant Natrix has a more flexible and less rigid spine than its ancestors. Overall, the vertebral differences among snake anatomical regions or taxa are a testament to the remarkable diversity and adaptability of these fascinating reptiles.

Modeling the Effect of Annulus Fibrosus Stiffness on the Stressed State of a Vertebral L1 Body and Nucleus Pulposus

The investigation examines the transference of stiffness from intervertebral discs (IVDs) to the lumbar body of the L1 vertebra and the interactions among adjacent tissues. A computational model of the vertebra was developed, considering parameters such as cortical bone thickness, trabecular bone elasticity, and the nonlinear response of the nucleus pulposus to external loading. A nonlinear dynamic analysis was performed, revealing certain trends: a heightened stiffness of the annulus fibrosus correlates with a significant reduction in the vertebral body's ability to withstand external loading. At a supplied displacement of 6 mm, the vertebra with a degenerative disc reached its yielding point, whereas the vertebrae with a healthy annulus fibrosus exhibited a strength capacity exceeding 20%. The obtained findings and proposed methodology are potentially useful for biomedical engineers and clinical specialists in evaluating the condition of the annulus fibrosus and predicting its influence on the bone components of the spinal system.

The effect of temporomandibular joint dysfunction on the craniocervical mandibular system: A retrospective study

BACKGROUND

Temporomandibular disorders are the most common condition affecting the orofacial region, resulting in pain and dysfunction.

OBJECTIVE

This study aimed to elucidate the ambiguous association between cervical features and temporomandibular disorders by measuring the rotations between the skull-atlas, atlas-axis and mandible-atlas and examining the relationship between these rotations and temporomandibular disorders.

METHODS

Cone-beam computed tomography (CBCT) images from 176 patients, 97 females and 79 males with an average age of 25.7 years were used in this study. The patients were divided into two groups: those with joint dysfunction (n = 88) and those without (n = 88). The study employed various methods to determine rotations in the skull-atlas, atlas-axis and mandible atlas based on anatomical landmarks and measurements. These methods include the use of specific planes, angles and distances to identify and measure rotation. Data analysis was performed using the TURCOSA statistical software (Turcosa Analytics Ltd Co, Turkey, www.turcosa.com.tr).

RESULTS

The results showed that the degree of rotation between the skull and the atlas was higher in the TMD group than in the control group (p < .001). Similarly, Atlas-axis rotation was significantly higher in the TMD group (p < .001). However, no significant difference was found between mandible atlas rotations in the two groups (p = .546). The study also found a significant difference between the direction of rotation between the atlas and axis and the direction of mandible atlas rotation (p < .001) as well as between skull and atlas rotations and mandible-atlas rotations (p < .001).

CONCLUSION

Overall, the study suggests that there is a relationship between the skeletal structures of the cranio-cervico-mandibular system and TMD. Skull-atlas and atlas-axis rotations may play an important role in the aetiology of TMD in individuals with TMD. Therefore, it is important to evaluate rotations in the skull-atlas-axis region for the treatment of TMD.

Development of the vertebra and fin skeleton in the lamprey and its implications for the homology of vertebrate vertebrae

BACKGROUND

Although vertebrae are the defining character of vertebrates, they are found only in rudimentary form in extant agnathans. In addition, the vertebrae of agnathans possess several unique features, such as elastin-like molecules as the main matrix component and late (post-metamorphosis) differentiation of lamprey vertebrae. In this study, by tracing the developmental process of vertebrae in lamprey, we examined the homology of vertebrae between lampreys and gnathostomes.

RESULTS

We found that the lamprey somite is first subdivided mediolaterally, with myotome cells differentiating medially and non-myotome cells emerging laterally. Subsequently, collagen-positive non-myotome cells surround the myotome. This pattern of somitogenesis is rather similar to that in amphioxi and sheds doubt on the presence of a sclerotome, in terms of mesenchyme cells induced by a signal from the notochord, in lamprey. Further tracing of non-myotome cell development revealed that fin cartilage develops in ammocoete larvae approximately 35 mm in body length. The development of the fin cartilage occurs much earlier than that of the vertebra whose development proceeds during metamorphosis.

CONCLUSION

We propose that the homology of vertebrae between agnathans and gnathostomes should be discussed carefully, because the developmental process of the lamprey vertebra is different from that of gnathostomes.

Fast field echo resembling CT using restricted echo-spacing (FRACTURE) MR sequence can provide craniocervical region images comparable to a CT in dogs

Magnetic resonance imaging (MRI) is essential for evaluating cerebellar compression in patients with craniocervical junction abnormalities (CJA). However, it is limited in depicting cortical bone because of its short T2 relaxation times, low proton density, and organized structure. Fast field echo resembling a computed tomography (CT) scan using restricted echo-spacing (FRACTURE) MRI, is a new technique that offers CT-like bone contrast without radiation. This study aimed to assess the feasibility of using FRACTURE MRI for craniocervical junction (CCJ) assessment compared with CT and conventional MRI, potentially reducing the need for multiple scans and radiation exposure, and simplifying procedures in veterinary medicine. CT and MRI of the CCJ were obtained from five healthy beagles. MRI was performed using three-dimensional (3D) T1-weighted, T2-weighted, proton density-weighted (PDW), single echo-FRACTURE (sFRACTURE), and multiple echo-FRACTURE (mFRACTURE) sequences. For qualitative assessment, cortical delineation, trabecular bone visibility, joint space visibility, vertebral canal definition, overall quality, and artifacts were evaluated for each sequence. The geometrical accuracy, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were quantified. Both sFRACTURE and CT images provided significantly higher scores for cortical delineation and trabecular bone visibility than conventional MRI. Joint space visibility and vertebral canal definition were similar to those observed on CT images, regardless of the MR sequence. In the quantitative assessment, the distances measured on T2-weighted images differed significantly from those measured on CT. There were no significant differences between the distances taken using T1-weighted, PD-weighted, sFRACTURE, mFRACTURE and those taken using CT. T1-weighted and sFRACTURE had a higher SNR for trabecular bone than CT. The CNR between the cortical bone and muscle was high on CT and FRACTURE images. However, the CNR between the cortical and trabecular bones was low in mFRACTURE. Similar to CT, FRACTURE sequences showed higher cortical delineation and trabecular bone visibility than T2-weighted, T1-weighted, and PDW CCJ sequences. In particular, sFRACTURE provided a high signal-to-noise ratio (SNR) of the trabecular bone and a high CNR between the cortical bone and muscle and between the cortical and trabecular bones. FRACTURE sequences can complement conventional MR sequences for bone assessment of the CCJ in dogs.

Vertebral pattern and morphology is determined during embryonic segmentation

BACKGROUND

The segmented nature of the adult vertebral column is based on segmentation of the paraxial mesoderm during early embryogenesis. Disruptions to embryonic segmentation, whether caused by genetic lesions or environmental stress, result in adult vertebral pathologies. However, the mechanisms linking embryonic segmentation and the details of adult vertebral morphology are poorly understood.

RESULTS

We induced border defects using two approaches in zebrafish: heat stress and misregulation of embryonic segmentation genes tbx6, mesp-ba, and ripply1. We assayed vertebral length, regularity, and polarity using microscopic and radiological imaging. In population studies, we find a correlation between specific embryonic border defects and specific vertebral defects, and within individual fish, we trace specific adult vertebral defects to specific embryonic border defects.

CONCLUSIONS

Our data reveal that transient disruptions of embryonic segment border formation led to significant vertebral anomalies that persist through adulthood. The spacing of embryonic borders controls the length of the vertebra. The positions of embryonic borders control the positions of ribs and arches. Embryonic borders underlie fusions and divisions between adjacent spines and ribs. These data suggest that segment borders have a dominant role in vertebral development.

The ups and downs of bone-marrow adipose tissue in space

Knowledge is rapidly accumulating on basic roles and modulation of bone-marrow adipose tissue (BMAT). Among key modulators are physical forces on bones as exerted by gravity and exercise. Studying humans returning from space has revealed that, in addition to physical forces, local energetics within the bone marrow can play modulatory roles.

Endoscopic view of the vertebra during laser balloon ablation of paroxysmal atrial fibrillation

Key Clinical Message

Left atrial posterior wall on the vertebra is often difficult to obtain stable tissue contact with ablation-catheter. Laser balloon ablation is effective because the compression from the vertebra can be visualized through endoscopy.

Abstract

When performing pulmonary vein isolation (PVI) with radiofrequency, left atrial posterior wall on the vertebra is often difficult to obtain stable tissue contact with ablation-catheter because of the movement of the ablation point. Laser balloon ablation is effective for the achievement of durable PVI in cases with such anatomical characteristics because the compression from the vertebra can be visualized through endoscopy.

The Osteoblast Transcriptome in Developing Zebrafish Reveals Key Roles for Extracellular Matrix Proteins Col10a1a and Fbln1 in Skeletal Development and Homeostasis

Zebrafish are now widely used to study skeletal development and bone-related diseases. To that end, understanding osteoblast differentiation and function, the expression of essential transcription factors, signaling molecules, and extracellular matrix proteins is crucial. We isolated Sp7-expressing osteoblasts from 4-day-old larvae using a fluorescent reporter. We identified two distinct subpopulations and characterized their specific transcriptome as well as their structural, regulatory, and signaling profile. Based on their differential expression in these subpopulations, we generated mutants for the extracellular matrix protein genes col10a1a and fbln1 to study their functions. The col10a1a-/- mutant larvae display reduced chondrocranium size and decreased bone mineralization, while in adults a reduced vertebral thickness and tissue mineral density, and fusion of the caudal fin vertebrae were observed. In contrast, fbln1-/- mutants showed an increased mineralization of cranial elements and a reduced ceratohyal angle in larvae, while in adults a significantly increased vertebral centra thickness, length, volume, surface area, and tissue mineral density was observed. In addition, absence of the opercle specifically on the right side was observed. Transcriptomic analysis reveals up-regulation of genes involved in collagen biosynthesis and down-regulation of Fgf8 signaling in fbln1-/- mutants. Taken together, our results highlight the importance of bone extracellular matrix protein genes col10a1a and fbln1 in skeletal development and homeostasis.

Finite element analysis of vertebroplasty in the osteoporotic T11-L1 vertebral body: Effects of bone cement formulation

Vertebral compression fractures are one of the most severe clinical consequences of osteoporosis and the most common fragility fracture afflicting 570 and 1070 out of 100,000 men and women worldwide, respectively. Vertebroplasty (VP), a minimally invasive surgical procedure that involves the percutaneous injection of bone cement, is one of the most efficacious methods to stabilise osteoporotic vertebral compression fractures. However, postoperative fracture has been observed in up to 30% of patients following VP. Therefore, this study aims to investigate the effect of different injectable bone cement formulations on the stress distribution within the vertebrae and intervertebral discs due to VP and consequently recommend the optimal cement formulation. To achieve this, a 3D finite element (FE) model of the T11-L1 vertebral body was developed from computed tomography scan data of the spine. Osteoporotic bone was modeled by reducing the Young's modulus by 20% in the cortical bone and 74% in cancellous bone. The FE model was subjected to different physiological movements, such as extension, flexion, bending, and compression. The osteoporotic model caused a reduction in the average von Mises stress compared with the normal model in the T12 cancellous bone and an increment in the average von Mises stress value at the T12 cortical bone. The effects of VP using different formulations of a novel injectable bone cement were modeled by replacing a region of T12 cancellous bone with the materials. Due to the injection of the bone cement at the T12 vertebra, the average von Mises stresses on cancellous bone increased and slightly decreased on the cortical bone under all loading conditions. The novel class of bone cements investigated herein demonstrated an effective restoration of stress distribution to physiological levels within treated vertebrae, which could offer a potential superior alternative for VP surgery as their anti-osteoclastogenic properties could further enhance the appeal of their fracture treatment and may contribute to improved patient recovery and long-term well-being.

Modular incorporation of deformable spine and 3D neck musculature into a simplified human body finite element model

Spinal injuries are a concern for automotive applications, requiring large parametric studies to understand spinal injury mechanisms under complex loading conditions. Finite element computational human body models (e.g. Global Human Body Models Consortium (GHBMC) models) can be used to identify spinal injury mechanisms. However, the existing GHBMC detailed models (with high computational time) or GHBMC simplified models (lacking vertebral fracture prediction capabilities) are not ideal for studying spinal injury mechanisms in large parametric studies. To overcome these limitations, a modular 50th percentile male simplified occupant model combining advantages of both the simplified and detailed models, M50-OS + DeformSpine, was developed by incorporating the deformable spine and 3D neck musculature from the detailed GHBMC model M50-O (v6.0) into the simplified GHBMC model M50-OS (v2.3). This new modular model was validated against post-mortem human subject test data in four rigid hub impactor tests and two frontal impact sled tests. The M50-OS + DeformSpine model showed good agreement with experimental test data with an average CORrelation and Analysis (CORA) score of 0.82 for the hub impact tests and 0.75 for the sled impact tests. CORA scores were statistically similar overall between the M50-OS + DeformSpine (0.79 ± 0.11), M50-OS (0.79 ± 0.11), and M50-O (0.82 ± 0.11) models (p > 0.05). This new model is computationally 6 times faster than the detailed M50-O model, with added spinal injury prediction capabilities over the simplified M50-OS model.

Left-Side Contrast-Injection-Induced Pseudopathologic Vertebral Enhancement in Oncology Patients without Venous Obstruction: A Report of Two Cases

The appearance of sclerotic bone lesions in contrast-enhanced computed tomography (CT) scans is often a significant concern for the possible presence of metastatic disease, especially in individuals with a known history of cancer. Prior research has demonstrated that in cases where patients suffer from thrombosis in major veins like the superior vena cava or the brachiocephalic vein, vertebral venous congestion can create imaging patterns on CT scans that resemble sclerotic bone metastases. However, instances of such imaging findings in patients without any form of venous obstruction are not commonly reported. In this study, we present cases of pseudopathologic vertebral enhancement observed consistently following left-side contrast injections in cancer patients devoid of venous obstruction. We aim to discuss and propose a potential mechanism for this phenomenon, drawing attention to a less commonly recognized diagnostic consideration in oncological imaging.

A Zebrafish Mutant in the Extracellular Matrix Protein Gene efemp1 as a Model for Spinal Osteoarthritis

Osteoarthritis is a degenerative articular disease affecting mainly aging animals and people. The extracellular matrix protein Efemp1 was previously shown to have higher turn-over and increased secretion in the blood serum, urine, and subchondral bone of knee joints in osteoarthritic patients. Here, we use the zebrafish as a model system to investigate the function of Efemp1 in vertebrate skeletal development and homeostasis. Using in situ hybridization, we show that the efemp1 gene is expressed in the brain, the pharyngeal arches, and in the chordoblasts surrounding the notochord at 48 hours post-fertilization. We generated an efemp1 mutant line, using the CRISPR/Cas9 method, that produces a severely truncated Efemp1 protein. These mutant larvae presented a medially narrower chondrocranium at 5 days, which normalized later at day 10. At age 1.5 years, µCT analysis revealed an increased tissue mineral density and thickness of the vertebral bodies, as well as a decreased distance between individual vertebrae and ruffled borders of the vertebral centra. This novel defect, which has, to our knowledge, never been described before, suggests that the efemp1 mutant represents the first zebrafish model for spinal osteoarthritis.

Automatic generation of subject-specific finite element models of the spine from magnetic resonance images

The generation of subject-specific finite element models of the spine is generally a time-consuming process based on computed tomography (CT) images, where scanning exposes subjects to harmful radiation. In this study, a method is presented for the automatic generation of spine finite element models using images from a single magnetic resonance (MR) sequence. The thoracic and lumbar spine of eight adult volunteers was imaged using a 3D multi-echo-gradient-echo sagittal MR sequence. A deep-learning method was used to generate synthetic CT images from the MR images. A pre-trained deep-learning network was used for the automatic segmentation of vertebrae from the synthetic CT images. Another deep-learning network was trained for the automatic segmentation of intervertebral discs from the MR images. The automatic segmentations were validated against manual segmentations for two subjects, one with scoliosis, and another with a spine implant. A template mesh of the spine was registered to the segmentations in three steps using a Bayesian coherent point drift algorithm. First, rigid registration was applied on the complete spine. Second, non-rigid registration was used for the individual discs and vertebrae. Third, the complete spine was non-rigidly registered to the individually registered discs and vertebrae. Comparison of the automatic and manual segmentations led to dice-scores of 0.93-0.96 for all vertebrae and discs. The lowest dice-score was in the disc at the height of the implant where artifacts led to under-segmentation. The mean distance between the morphed meshes and the segmentations was below 1 mm. In conclusion, the presented method can be used to automatically generate accurate subject-specific spine models.

Early experience with percutaneous balloon kyphoplasty for treatment of osteoporotic vertebral compression fracture in Nepal: A case report

Key Clinical Message

Balloon kyphoplasty is a promising treatment option for osteoporotic vertebral compression fractures with posterior cortical defect, offering pain relief, vertebral height restoration, and low risk of cement leakage.

Abstract

Millions of people worldwide suffer from osteoporotic vertebral compression fractures (OVCFs) annually, which cause pain and functional limitations, particularly in the elderly. Conservative treatments such as pain management, rest, and medication are frequently used, while surgical options such as vertebroplasty and kyphoplasty are considered. We present a case of 68-year-old female with vertebral compression fracture of L1 vertebra with posterior cortical defect and posterior wall retropulsion. She was treated successfully with balloon kyphoplasty. Kyphoplasty appears to be a better option than vertebroplasty in cases with posterior cortical defect due to lower chance of cement leakage.

Clinical outcomes after bracing for vertebral compression fractures: a systematic review and meta-analysis of randomized trials

Background

Vertebral compression fractures are common and result in significant pain and loss of function. Treatment strategy, however, remains controversial. We conducted a meta-analysis of randomized trials to elucidate the impact of bracing on these injuries.

Methods

A comprehensive literature review utilizing Embase, OVID MEDLINE, and the Cochrane Library was performed to identify randomized trials evaluating brace therapy for adult patients with thoracic and lumbar compression fractures. Two independent reviewers assessed the eligibility of studies and risk of bias. The primary assessed outcome was pain after injury. Secondary outcomes were function, quality of life, opioid use, and kyphotic progression [anterior vertebral body compression percentage (AVBCP)]. Continuous variables were analyzed using mean differences and standardized mean differences, and dichotomous variables were analyzed using odds ratios in random-effects models. GRADE criteria were applied.

Results

Of 1,502 articles, a total of 3 studies with 447 patients (96% female) were included. Fifty-four patients were managed without a brace, and 393 with a brace (195 rigid, 198 soft). At 3 to 6 months post-injury, rigid bracing resulted in significantly less pain compared to no brace (SMD =-1.32, 95% CI: -1.89 to -0.76, P<0.05, I2=41%), though this diminished at long-term follow-up of 48 weeks. Radiographic kyphosis, opioid use, function, or quality of life were not significantly different at any timepoint.

Conclusions

Moderate quality evidence demonstrates rigid bracing of vertebral compression fractures may decrease pain up to 6 months post-injury, though there is no difference in radiographic parameters, opioid use, function, or quality of life at short- or long-term follow-up. No difference was found between rigid and soft bracing; therefore, soft bracing may be an adequate alternative.

Ethanol Sclerosis Therapy for Aggressive Vertebral Hemangioma of the Spine: A Narrative Review

Vertebral hemangiomas of the spine are rare benign tumors. They occur primarily in the thoracic region and are often asymptomatic and found incidentally on radiological examination; however, some are symptomatic, aggressive, and gradually increase in size. Various therapeutic approaches have been proposed for their management. This study aimed to review the therapeutic management, focusing on ethanol sclerosis therapy. The PubMed database was searched from inception to January 2023 using the keywords "hemangioma", "spine OR vertebra", and "ethanol". Twenty studies were retrieved, including two letters. The first report of spinal therapy was published in 1994. Ethanol sclerosis therapy is effective in treating vertebral hemangiomas. It is performed independently or in combination with other techniques, such as vertebroplasty using cement and surgery. The therapy is performed under local or general anesthesia with fluoroscopic or computed tomography guidance. A total of 10-15 mL of ethanol is slowly injected via unilateral or bilateral pedicles. Complications of the therapy include hypotension and arrhythmia during the procedure, paralysis immediately after the procedure, and delayed compression fractures. This review could enable the refinement of knowledge regarding ethanol sclerosis therapy, which is a treatment option that could be adopted.

The changing landscape of spinal injuries: A narrative review

In the past, spinal trauma was frequent in high- and middle-income regions of the world with high rates of automobility and was considered a "young men's disease." However, over the last 2 decades, both of these factors have changed dramatically. This has had important implications for our methods of diagnosis, treatment, and the organization of care.

Effect of hormone replacement therapy on intervertebral disc height

OBJECTIVE

Intervertebral discs act as shock absorbers, thereby helping to reduce the risk of vertebral body fractures. Previous studies have shown that estrogen loss following menopause is associated with disc height reduction whereas treatment with hormone replacement therapy (HRT) helps to maintain disc height. This study reports the effect of HRT on disc height from a post hoc analysis of a prospective randomized clinical trial of the effect of HRT on bone density.

METHODS

A total of 355 healthy postmenopausal women aged (mean ± standard deviation) 55.4 ± 4.8 years were randomized to HRT with oral 1 mg or 2 mg estradiol plus dydrogesterone or placebo. Dual-energy X-ray absorptiometry measurements (Lunar DPX) were obtained at baseline and following 2 years of treatment. Intervertebral disc height was measured in discs between T12 and L3 using the bone densitometer ruler.

RESULTS

Compared with baseline, treatment with HRT resulted in a significant increase in total disc height with 1 mg estradiol (0.16 ± 0.65 cm, p = 0.015) and with 2 mg estradiol (0.21 ± 0.86 cm, p = 0.006) whilst there was no significant increase with placebo (0.13 ± 0.65 cm, p = 0.096). Between-group differences were not statistically significant.

CONCLUSIONS

These results are consistent with previous findings of a beneficial effect of estrogen on discs. This may be in part responsible for the anti-fracture efficacy of HRT on vertebral fractures.

Statistical multi-level shape models for scalable modeling of multi-organ anatomies

Statistical shape modeling is an indispensable tool in the quantitative analysis of anatomies. Particle-based shape modeling (PSM) is a state-of-the-art approach that enables the learning of population-level shape representation from medical imaging data (e.g., CT, MRI) and the associated 3D models of anatomy generated from them. PSM optimizes the placement of a dense set of landmarks (i.e., correspondence points) on a given shape cohort. PSM supports multi-organ modeling as a particular case of the conventional single-organ framework via a global statistical model, where multi-structure anatomy is considered as a single structure. However, global multi-organ models are not scalable for many organs, induce anatomical inconsistencies, and result in entangled shape statistics where modes of shape variation reflect both within- and between-organ variations. Hence, there is a need for an efficient modeling approach that can capture the inter-organ relations (i.e., pose variations) of the complex anatomy while simultaneously optimizing the morphological changes of each organ and capturing the population-level statistics. This paper leverages the PSM approach and proposes a new approach for correspondence-point optimization of multiple organs that overcomes these limitations. The central idea of multilevel component analysis, is that the shape statistics consists of two mutually orthogonal subspaces: the within-organ subspace and the between-organ subspace. We formulate the correspondence optimization objective using this generative model. We evaluate the proposed method using synthetic shape data and clinical data for articulated joint structures of the spine, foot and ankle, and hip joint.

Different Requirements of CBFB and RUNX2 in Skeletal Development among Calvaria, Limbs, Vertebrae and Ribs

RUNX proteins, such as RUNX2, regulate the proliferation and differentiation of chondrocytes and osteoblasts. Haploinsufficiency of RUNX2 causes cleidocranial dysplasia, but a detailed analysis of Runx2+/- mice has not been reported. Furthermore, CBFB is required for the stability and DNA binding of RUNX family proteins. CBFB has two isoforms, and CBFB2 plays a major role in skeletal development. The calvaria, femurs, vertebrae and ribs in Cbfb2-/- mice were analyzed after birth, and compared with those in Runx2+/- mice. Calvarial development was impaired in Runx2+/- mice but mildly delayed in Cbfb2-/- mice. In femurs, the cortical bone but not trabecular bone was reduced in Cbfb2-/- mice, whereas both the trabecular and cortical bone were reduced in Runx2+/- mice. The trabecular bone in vertebrae increased in Cbfb2-/- mice but not in Runx2+/- mice. Rib development was impaired in Cbfb2-/- mice but not in Runx2+/- mice. These differences were likely caused by differences in the indispensability of CBFB and RUNX2, the balance of bone formation and resorption, or the number and maturation stage of osteoblasts. Thus, different amounts of CBFB and RUNX2 were required among the bone tissues for proper bone development and maintenance.

Genetics of non-isolated hemivertebra: A systematic review of fetal, neonatal, and infant cases

Hemivertebra is a congenital vertebral malformation caused by unilateral failure of formation during embryogenesis that may be associated with additional abnormalities. A systematic review was conducted to investigate genetic etiologies of non-isolated hemivertebra identified in the fetal, neonatal, and infant periods using PubMed, Cochrane database, Ovid Medline, and ClinicalTrials.gov from inception through May 2022 (PROSPERO ID CRD42021229576). The Human Phenotype Ontology database was accessed May 2022. Studies were deemed eligible for inclusion if they addressed non-isolated hemivertebra or genetic causes of non-isolated hemivertebra identified in the fetal, neonatal, or infant periods. Cases diagnosed clinically without molecular confirmation were included. Systematic review identified 23 cases of non-isolated hemivertebra with karyotypic abnormalities, 2 cases due to microdeletions, 59 cases attributed to single gene disorders, 18 syndromic cases without known genetic etiology, and 14 cases without a known syndromic association. The Human Phenotype Ontology search identified 49 genes associated with hemivertebra. Non-isolated hemivertebra is associated with a diverse spectrum of cytogenetic abnormalities and single gene disorders. Genetic syndromes were notably common. Frequently affected organ systems include musculoskeletal, cardiovascular, central nervous system, genitourinary, gastrointestinal, and facial dysmorphisms. When non-isolated hemivertebra is identified on prenatal ultrasound, the fetus must be assessed for associated anomalies and genetic counseling is recommended.

Spondylolysis

Spondylolysis is a bony defect of the pars interarticularis and most often results from repetitive stress. Although spondylolysis is usually asymptomatic, symptomatic spondylolysis is the most common cause of identifiable back pain in children and adolescent athletes. A thorough history and physical exam, as well as appropriate imaging studies are helpful in diagnosis. General first-ine therapy for spondylolysis is conservative and consists of rest from sports, core strengthening, as well as spinal bracing. Patients who have failed conservative therapy may consider surgical repair. This article aims to review the epidemiology, pathophysiology, presentation, and treatment options of spondylolysis.

Age-based differences in the disability of spine injuries in pediatric and adult motor vehicle crash occupants

OBJECTIVE

The objective was to develop a disability-based metric for quantifying disability rates as a result of motor vehicle crash (MVC) spine injuries and compare functional outcomes between pediatric and adult subgroups.

METHODS

Disability rate was quantified using Functional Independence Measure (FIM) scores within the National Trauma Data Bank-Research Data System for the top 95% most frequent Abbreviated Injury Scale (AIS) 3 spine injuries (14 unique injuries). Pediatric (7-18 years), young adult (19-45 years), middle-aged adult (46-65 years), and older adult (66+ years) MVC occupants with FIM scores available and at least one of the 14 spine injuries were included. FIM scores of 1 or 2 at time of discharge were used to define disability and correspond to full functional or modified dependence in self-feeding, locomotion, and/or verbal expression. Disability rate was evaluated on a per injury basis for each AIS 3 spine injury and calculated as the proportion of cases associated with disability (i.e. FIM of 1 or 2) out of the total cases of that particular injury. Disability rates were calculated with and without the exclusion of cases with severe co-injuries (AIS 4+) to minimize bias from additional non-spinal injuries that could have contributed to disability. Associations between adjusted disability rates and existing mortality rates were investigated.

RESULTS

Locomotion impairment alone was the most frequent disability type for the top 14 AIS 3 spine injuries (7 cervical, 4 thoracic, and 3 lumbar) across all age groups and spine regions. Adjusted and unadjusted disability rates ranged from 0-69%. Adjusted disability rates increased with age: 14.8 ± 10% (mean ± SD) in pediatrics to 16.2 ± 6.6% (young adults), 29.2 ± 10.9% (middle-aged adults), and 45.0 ± 12.2% (older adults). Among all adult populations, adjusted mortality and disability rates were positively correlated (R²>0.24), with disability rates consistently greater than corresponding mortality rates.

CONCLUSIONS

Older adults had significantly greater disability rates associated with MVC spine injuries across all spinal regions. MVC disability rates for pediatrics were considerably lower. Overall, rates of mortality were significantly lower than rates of disability. The adjusted disability rates developed can supplement existing injury metrics by accounting for age- and location-specific functional implications of MVC spine injuries.

Microstructure and energy dispersive diffraction reconstruction of 3D patterns of crystallographic texture in a shark centrum

Purpose: Tomography using diffracted x-rays produces reconstructions mapping quantities such as crystal lattice parameter(s), crystallite size, and crystallographic texture, information quite different from that obtained with absorption or phase contrast. Diffraction tomography is used to map an entire blue shark centrum with its double cone structure (corpora calcerea) and intermedialia (four wedges). Approach: Energy dispersive diffraction (EDD) and polychromatic synchrotron x-radiation at 6-BM-B, the Advanced Photon Source, were used. Different, properly oriented Bragg planes diffract different x-ray energies; these intensities are measured by one of ten energy-sensitive detectors. A pencil beam defines the irradiated volume, and a collimator before each energy-sensitive detector selects which portion of the irradiated column is sampled at any one time. Translating the specimen along X , Y , and Z axes produces a 3D map. Results: We report 3D maps of the integrated intensity of several bioapatite reflections from the mineralized cartilage centrum of a blue shark. The c axis reflection's integrated intensities and those of a reflection with no c axis component reveal that the cone wall's bioapatite is oriented with its c axes lateral, i.e., perpendicular to the backbone's axis, and that the wedges' bioapatite is oriented with its c axes axial. Absorption microcomputed tomography (laboratory and synchrotron) and x-ray excited x-ray fluorescence maps provide higher resolution views. Conclusion: The bioapatite in the cone walls and wedges is oriented to resist lateral and axial deflections, respectively. Mineralized tissue samples can be mapped in 3D with EDD tomography and subsequently studied by destructive methods.

Supine correction index as a predictor for brace outcome in adolescent idiopathic scoliosis

Aims

The aim of this study was to assess the ability of morphological spinal parameters to predict the outcome of bracing in patients with adolescent idiopathic scoliosis (AIS) and to establish a novel supine correction index (SCI) for guiding bracing treatment.

Methods

Patients with AIS to be treated by bracing were prospectively recruited between December 2016 and 2018, and were followed until brace removal. In all, 207 patients with a mean age at recruitment of 12.8 years (SD 1.2) were enrolled. Cobb angles, supine flexibility, and the rate of in-brace correction were measured and used to predict curve progression at the end of follow-up. The SCI was defined as the ratio between correction rate and flexibility. Receiver operating characteristic (ROC) curve analysis was carried out to assess the optimal thresholds for flexibility, correction rate, and SCI in predicting a higher risk of progression, defined by a change in Cobb angle of ≥ 5° or the need for surgery.

Results

The baseline Cobb angles were similar (p = 0.374) in patients whose curves progressed (32.7° (SD 10.7)) and in those whose curves remained stable (31.4° (SD 6.1)). High supine flexibility (odds ratio (OR) 0.947 (95% CI 0.910 to 0.984); p = 0.006) and correction rate (OR 0.926 (95% CI 0.890 to 0.964); p < 0.001) predicted a lower incidence of progression after adjusting for Cobb angle, Risser sign, curve type, menarche status, distal radius and ulna grading, and brace compliance. ROC curve analysis identified a cut-off of 18.1% for flexibility (sensitivity 0.682, specificity 0.704) and a cut-off of 28.8% for correction rate (sensitivity 0.773, specificity 0.691) in predicting a lower risk of curve progression. A SCI of greater than 1.21 predicted a lower risk of progression (OR 0.4 (95% CI 0.251 to 0.955); sensitivity 0.583, specificity 0.591; p = 0.036).

Conclusion

A higher supine flexibility (18.1%) and correction rate (28.8%), and a SCI of greater than 1.21 predicted a lower risk of progression. These novel parameters can be used as a guide to optimize the outcome of bracing.

Cite this article: Bone Joint J 2022;104-B(4):495–503.

Retrospective stable isotopes of vertebrae reveal sexual ontogenetic patterns and trophic ecology in oceanic whitetip shark, Carcharhinus longimanus

There is a common phenomenon in nature whereby some animals have differences in their ontogenetic changes in dietary preferences between sexes, especially apex predators. These reflect changes in the needs of development during their lifetimes. Apex predators potentially have diverse dietary niches and a large impact on the trophic dynamics within ecosystems. However, the difference in life history between males and females often leads to increased difficulty in management and conservation. In this study, 25 oceanic whitetip sharks, Carcharhinus longimanus, were collected from the central and eastern tropical Pacific. Retrospective stable isotope analysis of vertebrae was used to evaluate the potential ontogenetic differences in feeding habits and niche width between sexes. Results showed that C. longimanus had a wide range of δ13C values (-18.1 to -12.3‰) and δ15N values (8.9-14.8‰). However, males and females had similar trophic positions with large niche overlap at similar growth stages. Both sexes had increasing δ13C values but relatively constant δ15N values along the vertebrae. These results indicated that male and female C. longimanus may share similar feeding strategies and movement patterns. The results presented in this study enhance our understanding of sexual ontogenetic patterns and ecological role of C. longimanus and highlighted the applicability of vertebrae for characterizing shark life-history traits.

Single-center outcomes of image-guided radiotherapy in the management of vertebral hemangioma with daily kilovoltage cone-beam computerized tomography

Background

Vertebral hemangiomas are defined as benign proliferation of blood vessels. Vertebral hemangiomas are generally found incidentally by computerized tomography or magnetic resonance imaging; however, they may also cause pain and quality-of-life impairment in some circumstances with reference to their location and association with the spinal cord. In this study, we assessed the utility of image-guided radiation therapy (IGRT) in the management of patients with painful vertebral hemangioma.

Materials and Methods

Patients receiving IGRT for the management of painful vertebral hemangioma were evaluated. The total dose was 24 Gy delivered in 12 daily fractions. The verbal numeric scale (VNS) was used for the assessment of pain relief. The median follow-up duration was 13 months (range: 6-24 months).

Results

Median preradiotherapy VNS score was 8 (range: 6-10) and median postradiotherapy VNS score was 1 (range: 0-2) for the total 135 patients treated with IGRT at our department for painful vertebral hemangioma. Reduction in VNS scores after IGRT was statistically significant (P < 0.05).

Conclusion

Our single-center study revealed that IGRT resulted in substantial relief of pain from vertebral hemangioma. Randomized prospective multicenter trials are needed to shed light on the optimal management of patients suffering from pain due to vertebral hemangioma.

Low Anterior Cervical Approach Without Sternotomy or Clavicle Resection for Upper Thoracic Vertebra Corpectomy

The spine is the third most common site for metastatic disease following the lung and the liver. Approximately 60-70% of patients with metastatic cancer will have metastasis to the spine, but only 10% of these will be symptomatic. Metastases to the spine may involve the bone, epidural space, or the spinal cord. While chemotherapy and radiation therapy are the primary treatments for metastatic disease, spinal cord compression is an indication for surgical intervention. For vertebral body lesions, anterior vertebral reconstruction and stabilization also have the advantage of providing immediate stability to the vertebral column, but this anterior surgical approach to the upper thoracic spine is fraught with complications. The approach typically involves some combination of thoracotomy, sternotomy, or clavicle resection with anterior dissection into the superior mediastinum. To avoid unnecessary sternotomy and its associated complications, surgical access without sternotomy can be performed in certain cases. A sagittal MRI scan of the spine can be used to evaluate the level of the sternal notch in relation to the upper thoracic spine. If a tangential line can be drawn superior to the sternal notch and inferior to the level of the involved vertebra, surgical access without sternotomy can be performed. We present a case of a 52-year-old female with metastases to the upper thoracic vertebrae who underwent successful T2 corpectomy and T1-3 anterior fusion via a low anterior cervical approach, without sternotomy or clavicle resection.

MRI features of canine hemangiosarcoma affecting the central nervous system

Hemangiosarcoma is the most common metastatic tumor involving the brain in dogs but detailed published descriptions of the magnetic resonance imaging (MRI) features are lacking. The objective of this multi-center, retrospective case series study was to describe MRI characteristics of canine hemangiosarcoma affecting the central nervous system (CNS). Medical records of seven referral institutions were retrospectively reviewed. Dogs were included if they had a histopathologically confirmed diagnosis of hemangiosarcoma affecting the CNS and undergone an MRI of the brain and/or vertebral column. Lesions were independently evaluated by two observers. Twenty dogs met the inclusion criteria and one dog had both intracranial and intramedullary hemangiosarcoma. Consistent MRI features included heterogeneous (17/21) lesions in all sequences with mainly mixed signal intensity (12/21), presence of susceptibility artifact on T2*w (15/16), associated moderate to severe perilesional edema (21/21), and moderate to strong (20/21) heterogeneous (14/21) or ring-like (6/21) contrast enhancement. Intracranial hemangiosarcoma was frequently multiple and intra-axial, affecting consistently the telencephalon and no differences in MRI features were found between primary and metastatic hemangiosarcoma. This is the first MRI description of primary intracranial hemangiosarcoma and primary intracranial epithelioid hemangiosarcoma. Vertebral hemangiosarcomas were segmental poorly marginated polyostotic and highly aggressive lesions invading the thoracic vertebral canal and paraspinal tissues. Epidural hemangiosarcomas were single and well-marginated lesions in the thoracolumbar and/or lumbar region. Intramedullary hemangiosarcomas were cervical, metastatic in origin, and frequently (3/4) accompanied by intracranial lesions. These described MRI features will aid early identification of hemangiosarcoma guiding subsequent diagnostics and therapeutics.

Effects Induced by Osteophytes on the Strain Distribution in the Vertebral Body Under Different Loading Configurations

The mechanical consequences of osteophytes are not completely clear. We aimed to understand whether and how the presence of an osteophyte perturbs strain distribution in the neighboring bone. The scope of this study was to evaluate the mechanical behavior induced by the osteophytes using full-field surface strain analysis in different loading configurations. Eight thoracolumbar segments, containing a vertebra with an osteophyte and an adjacent vertebra without an osteophyte (control), were harvested from six human spines. The position and size of the osteophytes were evaluated using clinical computed tomography imaging. The spine segments were biomechanically tested in the elastic regime in different loading configurations while the strains over the frontal and lateral surface of vertebral bodies were measured using digital image correlation. The strain fields in the vertebrae with and without osteophytes were compared. The correlation between osteophyte size and strain alteration was explored. The strain fields measured in the vertebrae with osteophytes were different from the control ones. In pure compression, we observed a mild trend between the size of the osteophyte and the strain distribution (R² = 0.32, p = 0.15). A slightly stronger trend was found for bending (R² = 0.44, p = 0.075). This study suggests that the osteophytes visibly perturb the strain field in the nearby vertebral area. However, the effect on the surrounding bone is not consistent. Indeed, in some cases the osteophyte shielded the neighboring bone, and in other cases, the osteophyte increased the strains.

Generation of Vertebra Micro-CT-like Image from MDCT: A Deep-Learning-Based Image Enhancement Approach

This paper proposes a deep-learning-based image enhancement approach that can generate high-resolution micro-CT-like images from multidetector computed tomography (MDCT). A total of 12,500 MDCT and micro-CT image pairs were obtained from 25 vertebral specimens. Then, a pix2pixHD model was trained and evaluated using the structural similarity index measure (SSIM) and Fréchet inception distance (FID). We performed subjective assessments of the micro-CT-like images based on five aspects. Micro-CT and micro-CT-like image-derived trabecular bone microstructures were compared, and the underlying correlations were analyzed. The results showed that the pix2pixHD method (SSIM, 0.804 ± 0.037 and FID, 43.598 ± 9.108) outperformed the two control methods (pix2pix and CRN) in enhancing MDCT images (p < 0.05). According to the subjective assessment, the pix2pixHD-derived micro-CT-like images showed no significant difference from the micro-CT images in terms of contrast and shadow (p > 0.05) but demonstrated slightly lower noise, sharpness and trabecular bone texture (p < 0.05). Compared with the trabecular microstructure parameters of micro-CT images, those of pix2pixHD-derived micro-CT-like images showed no significant differences in bone volume fraction (BV/TV) (p > 0.05) and significant correlations in trabecular thickness (Tb.Th) and trabecular spacing (Tb.Sp) (Tb.Th, R = 0.90, p < 0.05; Tb.Sp, R = 0.88, p < 0.05). The proposed method can enhance the resolution of MDCT and obtain micro-CT-like images, which may provide new diagnostic criteria and a predictive basis for osteoporosis and related fractures.

Effect of captivity on the vertebral bone microstructure of xenarthran mammals

Captive specimens in museum collections facilitate study of rare taxa, but the lifestyles, diets, and lifespans of captive animals differ from their wild counterparts. Trabecular bone architecture adapts to in vivo forces, and may reflect interspecific variation in ecology and behavior as well as intraspecific variation between captive and wild specimens. We compared trunk vertebrae bone microstructure in captive and wild xenarthran mammals to test the effects of ecology and captivity. We collected μCT scans of the last six presacral vertebrae in 13 fossorial, terrestrial, and suspensorial xenarthran species (body mass: 120 g to 35 kg). For each vertebra, we measured centrum length; bone volume fraction (BV.TV); trabecular number and mean thickness (Tb.Th); global compactness (GC); cross-sectional area; mean intercept length; star length distribution; and connectivity and connectivity density. Wild specimens have more robust trabeculae, but this varies with species, ecology, and pathology. Wild specimens of fossorial taxa (Dasypus) have more robust trabeculae than captives, but there is no clear difference in bone microstructure between wild and captive specimens of suspensorial taxa (Bradypus, Choloepus), suggesting that locomotor ecology influences the degree to which captivity affects bone microstructure. Captive Tamandua and Myrmecophaga have higher BV.TV, Tb.Th, and GC than their wild counterparts due to captivity-caused bone pathologies. Our results add to the understanding of variation in mammalian bone microstructure, suggest caution when including captive specimens in bone microstructure research, and indicate the need to better replicate the habitats, diets, and behavior of animals in captivity.

Age-related change in shear elastic modulus of the thoracolumbar multifidus muscle in healthy Beagle dogs using ultrasound shear wave elastography

Background

Multifidus muscle stiffness decreases in patients with lumbar intervertebral disk herniation; however, age-related changes in humans have not been reported.

Objectives

The reliability of ultrasound shear wave elastography in dogs, and changes in the shear elastic modulus of the thoracolumbar multifidus muscle with aging in dogs, were investigated.

Methods

Twelve beagle dogs were divided into 2 groups based on the age of onset of intervertebral disk herniation: young (aged not exceeding 2 years; 1.3 ± 0.6 years old, n = 5) and adult (4.9 ± 1.2 years old, n = 7). The shear elastic modulus of the multifidus muscle, from the thirteenth thoracic spine to the fourth lumbar spine, was measured using ultrasound shear wave elastography. The length, cross-sectional area and muscle to fat ratio of the multifidus muscle, and the grade of intervertebral disk degeneration, were assessed using radiographic and magnetic resonance imaging examinations.

Results

The length and cross-sectional area of the multifidus muscle increased caudally. In the young group, the shear elastic modulus of the multifidus muscle of the thirteenth thoracic spine was less than that of the third lumbar spine. In the adult group, the shear elastic modulus of the multifidus muscle of first and third lumbar spine was lower than that of the same site in the young group.

Conclusions

Ultrasound can be used to measure shear wave elastography of the thoracolumbar multifidus in dogs. If the multifidus muscle stiffness decreases, we should consider age-related change.

Morphometric analysis of cervical vertebrae in some marine and land mammals

Bones or skeletal remains can be used to answer a number of questions related to species, sex, age or cause of death. However, studies involving vertebrae have been limited as most were performed on skulls or long bones. Here, we have stated the hypothesis that the morphometry of cervical vertebrae can be used for species identification and body size estimation among marine and land mammals. The cervical vertebrae from eight and 14 species of marine and land mammals were used to collect morphometric data. Cluster dendrogram, principal component analysis, discriminant analysis and linear regression were used to analyse the data. The results indicate that, based on an index of C4 to C7, there were 13 out of 22 species for which identity could be correctly predicted in 100% of the cases. The correlations between cervical vertebrae parameters (height, width and length of centrum) in marine (average R^2 =  0.87, p < .01) and land (average R^2 =  0.51, p < .01) mammals were observed. These results indicate that vertebral morphometrics could be used for species prediction and verification of body weight in both marine and land mammals.

Dual-Energy Computed Tomography in Spine Fractures: A Systematic Review and Meta-Analysis

BACKGROUND

The purpose of this study was to perform a systematic literature review and meta-analysis to evaluate the sensitivity, specificity, and accuracy of dual-energy computed tomography (DE-CT) of bone marrow edema and disc edema in spine injuries.In vertebral injuries, prompt diagnosis is essential to avoid any delays in treatment. Conventional radiography may only reveal indirect signs of fractures, such as when it is displaced. Therefore, to detect the presence of bone marrow or disc edemas, adjunctive tools are required, such as magnetic resonance imaging (MRI) or DE-CT.

METHODS

Search terms included ((DECT) OR (DE-CT) OR (dual-energy CT) OR "Dual energy CT" OR (dual-energy computed tomography) OR (dual energy computed tomography)) AND ((spine) OR (vertebral)), and the PubMed, EMBASE, and MEDLINE databases and the Cochrane Library and Google were used. We found 1233 articles on our preliminary search, but only 13 articles met all criteria. Data were extracted to calculate the pooled sensitivity, specificity, and diagnostic odds ratio for analysis using R software.

RESULTS

Within the 13 studies, 515 patients, 3335 vertebrae, and 926 acute fractures (27.8%) defined by MRI were included. The largest cohort included 76 patients with 774 vertebrae. In 12 publications, MRI was reported for comparison. For DE-CT, the overall sensitivity was 86.2% with a specificity of 91.2% and accuracy of 89.3%. Furthermore, 5 studies reported the accuracy of CT with an overall sensitivity of 81.3%, specificity of 80.7%, and accuracy with 80.9%. Significant differences were found for specificity (P < .001) and accuracy (P = .023). However, significant interobserver differences were reported.

CONCLUSIONS

DE-CT seems to be a promising diagnostic tool to detect bone marrow and disc edemas, which can potentially replace the current gold standard, the MRI.

LEVEL OF EVIDENCE

2.

CLINICAL RELEVANCE

This study shows that DE-CT seems to be a promising diagnostic tool with an accuracy of 89.3%.

Imaging of Spinal Bone Tumors: Principles and Practice

Age, location of the tumor, and detailed patient history can narrow the differential diagnosis of spinal bone lesions, including metastasis and primary benign and malignant bone tumors. Computed tomography and magnetic resonance imaging are both crucial in evaluating the characteristics of spinal bone tumors. Growth speed and Lodwick margin description can differentiate malignant from benign tumors to a certain degree. Positron emission tomography has a limited ability to differentiate malignant from benign tumors. Biopsy is often required for a definitive diagnosis. To select the optimal treatment for spinal metastasis, neurological status by epidural spinal cord compression grade (axial T2-weighted magnetic resonance image), radiosensitivity of tumor histology, mechanical instability by Spine Instability Neoplastic Score (sagittal and axial computed tomography image), and systemic disease should be evaluated by a multidisciplinary team. This review article summarizes the role of imaging for diagnosis and treatment of spinal bone tumors.

Functional Outcome of Kyphoplasty in Osteoporotic Vertebral Fractures in Patients with Severe Disability Above 60 Years of Age: Mid to Long Term Follow up

BACKGROUND

 Vertebral osteoporotic fractures are a worldwide problem and can cause significant morbidity.

MATERIAL AND METHODS

retrospective analysis reviewing functional outcome of 70 patients who underwent balloon-kyphoplasty(BK). Inclusion criteria, a-patients above 60 years of age b-symptomatic patients who failed conservative treatment c-radiological diagnosis of vertebral compression fracture(VCF). Primary outcome was evaluation of functional outcome in mid- (1-3 years) and long term (&gt;3 years). Secondary outcomes a-analysis of the functional outcome of patients with severe disability or worse in mid- and long-term b-comparison of functional outcome between mid-term and long term follow-up c-correlate number of levels operated on with functional outcome.

RESULTS

There were 70 patients with average age of 74 years. Lumbar and thoracic VCFs were included. Average follow-up was 2.7 years. Twenty-eight patients had long-term follow-up of ≥ 3 years and the remaining 42 had mid-term follow-up of &gt; 1 year and &lt; 3 years. All patients experienced clinical and statistically significant improvement in their Oswestry Disability Index score. This was the case in mid-term and long-term follow-up. This was also the case for patients presenting with severe disability. There was no correlation between the number of levels and functional outcome.

CONCLUSIONS

1. Osteoporotic vertebral compression fractures are fragility fractures and can be associated with significant morbidity. 2. Surgical treatment can help improve functional outcome on failure of conservative treatment. 3. Balloon kyphoplasty can significantly improve pa-tients' functional outcome in mid-term and long-term follow-up including patients presenting with severe disability or worse. 4. This study is of value in consenting kyphoplasty patients as they can expect an improvement in their disability in the mid-to-long term.

Differentiating Between Multiple Myeloma and Metastasis Subtypes of Lumbar Vertebra Lesions Using Machine Learning-Based Radiomics

Objective

To determine whether machine learning based on conventional magnetic resonance imaging (MRI) sequences have the potential for the differential diagnosis of multiple myeloma (MM), and different tumor metastasis lesions of the lumbar vertebra.

Methods

We retrospectively enrolled 107 patients newly diagnosed with MM and different metastasis of the lumbar vertebra. In total 60 MM lesions and 118 metastasis lesions were selected for training classifiers (70%) and subsequent validation (30%). Following segmentation, 282 texture features were extracted from both T1WI and T2WI images. Following regression analysis using the least absolute shrinkage and selection operator (LASSO) algorithm, the following machine learning models were selected: Support‐Vector Machine (SVM), K-Nearest Neighbor (KNN), Random Forest (RF), Artificial Neural Networks (ANN), and Naïve Bayes (NB) using 10-fold cross validation, and the performances were evaluated using a confusion matrix. Matthews correlation coefficient (MCC), sensitivity, specificity, and accuracy of the models were also calculated.

Results

To differentiate MM and metastasis, 13 features in the T1WI images and 9 features in the T2WI images were obtained. Among the 10 classifiers, the ANN classifier from the T2WI images achieved the best performance (MCC = 0.605) with accuracy, sensitivity, and specificity of 0.815, 0.879, and 0.790, respectively, in the validation cohort. To differentiate MM and metastasis subtypes, eight features in the T1WI images and seven features in the T2WI images were obtained. Among the 10 classifiers, the ANN classifier from the T2WI images achieved the best performance (MCC = 0.560, 0.412, 0.449), respectively, with accuracy = 0.648; sensitivity 0.714, 0.821, 0.897 and specificity 0.775, 0.600, 0.640 for the MM, lung, and other metastases, respectively, in the validation cohort.

Conclusions

Machine learning–based classifiers showed a satisfactory performance in differentiating MM lesions from those of tumor metastasis. While their value for distinguishing myeloma from different metastasis subtypes was moderate.

Epithelioid Hemangioma of Vertebra Mimicking Metastasis on FDG PET/CT in a Patient With Renal Cell Cancer

ABSTRACT

Vertebral epithelioid hemangioma is a rare vascular tumor composed of the many vessels lined by distinct epithelioid endothelial cells. We present the case of a patient with renal cell cancer (RCC) and suspicious vertebral metastasis presenting with back pain, who was later found to have epithelioid hemangioma. FDG PET/CT demonstrated uptake of FDG not only in RCC, but also in the sixth thoracic vertebral body. The SUVmax of the vertebra was more than twice as high as RCC. This report indicates importance of quantitative assessment of FDG uptake, as well as combined use of MRI.

A Case of Diastematomyelia Presenting With Minimal Neurologic Deficits in a Middle-Aged Patient

Diastematomyelia is a rare congenital deformity of the spine in which the spinal cord is split into two hemicords along the sagittal plane. This condition belongs to the group of spinal dysraphisms, is more common in females, and is usually diagnosed prenatally or during childhood; rarely is it diagnosed in adults. We report a male patient in his 50s in which diastematomyelia of the thoracic spine was incidentally encountered after receiving a CT scan of the chest for shortness of breath. Although most patients with this condition are symptomatic, the patient did not display any significant acute neurological complaints at the time. The patient had a history of spina bifida and is paraplegic, both of which are commonly associated with diastematomyelia. The lack of progressive neurologic symptoms, diagnosis in the patient’s adult life, and the presence of the anomaly solely in the thoracic spine make this a rare and unusual case. Early recognition and diagnosis of this condition, by prenatal ultrasound or MRI, can help to prevent further damage to the spinal cord and allow affected patients to seek treatment sooner, thus improving quality of life.

Quantitative evaluation of bone marrow infiltration using dual-energy spectral computed tomography in patients with multiple myeloma

OBJECTIVE

To explore the potential value of quantitative parameters derived from dual-energy spectral computed tomography (DESCT) as comparing to the parameters derived from magnetic resonance imaging (MRI) in detecting bone marrow (BM) infiltration and distinguishing different patterns of BM infiltration in patients diagnosed with Multiple myeloma (MM).

METHODS

This study involved 35MM patients and 15 healthy control subjects who had undergone spinal DESCT and MRI. Pattern assignment was based on visual assessment of MR images, and the regions of interest were defined on both DESCT and apparent diffusion coefficient maps. Quantitative values of DESCT parameters were measured and compared between infiltrated and healthy bone marrow. Receiver operating characteristic (ROC) analysis was performed to determine potential utility of DESCT parameters in identifying BM infiltration and different patterns defined by MRI. Sensitivity and specificity under the optimal thresholds determined by the Youden Index were also calculated.

RSULTS

Statistical differences were observed between the DESCT parameters including Ca(Water), Water(Ca), HAP(Fat), Fat(HAP) and Effective atomic number (Eff-Z) but not for the 70-keV CT value between the infiltrated and healthy BM (all P < 0.001). The 70keV CT value and Ca(Water), HAP(Fat) and Eff-Z values were also found to be statistically different in comparing different infiltration patterns (all P < 0.05). Performance of the model-based parameter Ca/Water was superior in differentiating between infiltrated and healthy BM in which the area under ROC curve, AUC = 0.856 [95% CI, 81.4-89.1%] with sensitivity = 0.841 and specificity = 0.768, as well as between MM patients and control subjects (AUC = 0.910 [95% CI, 79.5-97.3%], sensitivity = 0.829 and specificity = 1.000).

CONCLUSIONS

Analysis of DESCT offers potential as a quantitative method to detect infiltrated BM and evaluate infiltration patterns of BM in patients diagnosed with MM.

Spondylodiscitis in Children: A Retrospective Study and Comparison With Non-vertebral Osteomyelitis

Objectives: The aim of this study is to provide new data on pediatrics spondylodiscitis for an optimal clinical management of this site-specific osteomyelitis. Methods: We reported 48 cases of pediatric spondylodiscitis and made three comparisons between: (1) tubercular and non-tubercular cases; (2) patients aged more or less than 5 years; (3) children with spondylodiscitis and 62 controls with non-vertebral osteomyelitis. Results: A higher rate of sequelae was reported in patients with tubercular spondylodiscitis, but no significant differences were noted at the cut-off of 5 years of age. Compared to non-vertebral osteomyelitis, pediatric spondylodiscitis affects younger children of both genders, usually presenting with afebrile back pain, and requiring longer time to admission, hospitalization, and antibiotic therapy. Conclusion: Pediatric spondylodiscitis is an insidious disease with a non-specific presentation in childhood and peculiarities of its own. However, when clinical remission is obtained by an early start of broad-spectrum antibiotics, prolonging the therapy does not improve, nor worsens, the outcome. Surgical management is mandatory in case of vertebral instability and neurological signs but can be avoided when the infection is promptly treated with antibiotic therapy.

Primary multiple angiosarcoma of vertebra: A case report

RATIONALE

Angiosarcoma is a rare malignant tumors. The objective of this study is to report a patient who suffered from a progressive low back pain and left lower extremities radiation pain for about 8 months, After diagnoses, this was identified as an extremely rare case of primary multiple angiosarcoma of vertebra.

PATIENT CONCERNS

A 54-year-old man with a history of 2-year hypertension and 8-year diabetes, both of which were well controlled by drug management. Lately, he suffered from a progressive low back pain and left lower extremities radiation pain for about 8 months.

DIAGNOSES

Magnetic resonance imaging of lumbar showed a clear pathological fracture and primary multiple angiosarcoma of all vertebra. Postoperative pathology and High-throughput sequencing confirmed the diagnosis of primary multiple angiosarcoma of vertebra.

INTERVENTIONS

The patient underwent minimally invasive pedicle screw fixation combined with bone cement augmentation for the purpose of stabilizing the damaged vertebrae. Following operation, he received both radiotherapy and chemotherapy for a period of time.

OUTCOMES

The operation has achieved positive results in relieving pain and stabilizing the spine. No wound problem or operative complications occurred after operation. The patient reported an obvious remission of low back pain and was only capable to perform restricted physiological activities. A long-term palliative radiotherapy and chemotherapy were performed after operation. Unfortunately, the patient died 18 months later.

CONCLUSION

This article emphasizes primary multiple angiosarcoma of vertebra. Despite being rare, it should be part of the differential when the patient manifested back pain and radiculopathy. We recommended the minimally invasive pedicle screw fixation for angiosarcoma of vertebra. Osteoplasty by bone cement augmentation was also an ideal choice for surgical treatment. It also advocates the use of specific targeted radiotherapy drugs based on gene analysis of tumors.

Eikenella Corrodens Vertebral Osteomyelitis in a Young Patient With Type I Diabetes Mellitus

Vertebral osteomyelitis is an uncommon variant of osteomyelitis. Although Staphylococcus and/or Streptococcus are commonly associated, alternate pathogens have been implicated in vertebral osteomyelitis, especially in endemic areas and/or immunocompromised patients. Here, we present a case of a young African American female with type I diabetes mellitus who presented to us with worsening back pain. The MRI lumbar spine was suggestive of vertebral osteomyelitis involving the right facet joint of the fifth lumbar (L5) and the first spinal (S1) joint and a significant narrowing of the thecal sac at the L4-L5 vertebral level with an anterior epidural abscess. The patient was started on empirical antibiotics, and surgical intervention was performed with L4-L5 laminectomy and extraction of the epidural abscess. Her pus culture showed Eikenella corrodens as a possible cause of vertebral osteomyelitis. She had an uneventful recovery after two weeks of antibiotics (intravenous ceftriaxone) therapy.

Assessing the Mechanical Weakness of Vertebrae Affected by Primary Tumors: A Feasibility Study

Patients spend months between the primary spinal tumor diagnosis and the surgical treatment, due to the need for performing chemotherapy and/or radiotherapy. During this period, they are exposed to an unknown risk of fracture. The aim of this study was to assess if it is possible to measure the mechanical strain in vertebrae affected by primary tumors, so as to open the way to an evidence-based scoring or prediction tool. We performed biomechanical tests on three vertebrae with bone tumor removed from patients. The tests were designed so as not to compromise the standard surgical and diagnostic procedures. Non-destructive mechanical tests in combination with state-of-the-art digital image correlation allowed to measure the distribution of strain on the surface of the vertebra. Our study has shown that the strains in the tumor region is circa 3 times higher than in the healthy bones, with principal strain peaks of 40,000/-20,000 microstrain, indicating a stress concentration potentially triggering vertebral fracture. This study has proven it is possible to analyze the mechanical behavior of primary tumor vertebrae as part of the clinical treatment protocol. This will allow building a tool for quantifying the risk of fracture and improving decision making in spine tumors.

Bone histology and microanatomy of Edaphosaurus and Dimetrodon (Amniota, Synapsida) vertebrae from the Lower Permian of Texas

Here we describe the histology and microanatomy of vertebral centra of the iconic pelycosaur-grade synapsids Edaphosaurus boanerges and Dimetrodon spp. Vertebrae from different axial positions and, in the case of Dimetrodon, from different ontogenetic stages were selected. For the histological description, we produced histological petrographic thin sections ground to a thickness of 50-80 μm of the vertebrae in the sagittal and transversal cutting planes. After the preparation process, the thin sections were examined under transmitted and cross-polarized light in a polarized microscope. The analyzed vertebrae reveal similar bone tissues, where both taxa have cortical parallel-fibered bone (PFB). PFB and lamellar bone (LB) forms in the cancellous part. However, in juvenile Dimetrodon, woven-fibered bone (WFB) is also deposited and shows a high degree of vascularity. This suggests that Dimetrodon had slightly faster bone growth than Edaphosaurus, which is mainly made of PFB and LB and shows poorly developed vascular canals. In addition, one specimen of Dimetrodon displays the preservation of an ossified notochord, which can be assumed to be indicative of how the intervertebral tissues were developed. Historically, evidence of how the joint between Dimetrodon vertebral centra was built was lacking until this specimen appeared. If the notochord ran persistently through the vertebrae, it would have possibly increased the stiffness of the vertebral column and would have affected the limbs and locomotion. Furthermore, the organization of trabeculae and relative thickness of the vertebral cortex gives insights into how the animals were adapted to their habitat.

Proximal Descending Thoracic Aortic Pseudoaneurysm Secondary to Pott's Spine

Tuberculous pseudoaneurysm of the descending thoracic aorta is quite rare, life-threatening, and fatal if not diagnosed in time. This lesion exposes patients to a very high risk of unpredictable rupture. We describe a case of tuberculous pseudoaneurysm of the aorta in association with tuberculosis of the spine (Pott's spine). A 73-year-old man presented with a 2-month history of back pain. Chest roentgenography and contrast-enhanced computed tomography showed a descending thoracic aortic pseudoaneurysm with destruction of the fourth and fifth thoracic vertebrae (T4-T5). We suspected that the pseudoaneurysm was due to direct extension of tuberculous vertebral osteomyelitis. The patient was managed with antituberculous chemotherapy. The post-antitubercular therapy course was uneventful and he remained well 12 months after completion of treatment.

Optimizing computational methods of modeling vertebroplasty in experimentally augmented human lumbar vertebrae

Vertebroplasty has been widely used for the treatment of osteoporotic compression fractures but the efficacy of the technique has been questioned by the outcomes of randomized clinical trials. Finite-element (FE) models allow an investigation into the structural and geometric variation that affect the response to augmentation. However, current specimen-specific FE models are limited due to their poor reproduction of cement augmentation behavior. The aims of this study were to develop new methods of modeling the vertebral body in both a nonaugmented and augmented state. Experimental tests were conducted using human lumbar spine vertebral specimens. These tests included micro-computed tomography imaging, mechanical testing, augmentation with cement, reimaging, and retesting. Specimen-specific FE models of the vertebrae were made comparing different approaches to capturing the bone material properties and to modeling the cement augmentation region. These methods significantly improved the modeling accuracy of nonaugmented vertebrae. Methods that used the registration of multiple images (pre- and post-augmentation) of a vertebra achieved good agreement between augmented models and their experimental counterparts in terms of predictions of stiffness. Such models allow for further investigation into how vertebral variation influences the mechanical outcomes of vertebroplasty.