Vertebral Spine Research Articles

Why Is There Always a Remnant Rib Hump Deformity after Spinal Operations in Idiopathic Scoliosis: Aetiological Implications and Recognition of the Proper Rib Level for Costoplasty.

The aim of this report is to review the literature dealing with the postoperative correction of rib hump (RH) after spinal operations for adolescent idiopathic scoliosis (AIS) and its aetiological implications of hump postoperative fate for IS. Recommendations related to RH deformity for the follow-up of younger asymmetric but not scoliotic children are provided, and the concept that clinical monitoring of the chest deformity is more important than merely an initially negative radiographic examination (curve less than 10°) is underlined. Additionally, guidelines are provided based on the segments T1-T12 rib index (RI) in the existing lateral preoperative radiographs for the optimal selection of the rib level for a successfully costoplasty. This review is based on the collected articles that used either the RI method, derived from the double rib contour sign (DRCS) at the lateral spinal radiographs, or alternative methods for the assessment of the RH deformity and presented the results of the operative treatment of the scoliotic spine on RH. A total of 19 relevant articles published from 1976 to 2022 were found in PubMed. Findings: All the above articles show that not only is the hump incompletely corrected, but it recurs and worsens during the follow-up and even more intensively in skeletally immature operated scoliosis children. Conclusions and Future Directions: Surgery straightens the spine, yet the RH is corrected approximately only as much as the spinal derotation. The only way to correct the RH more is with costoplasty, which, however, is not performed in most cases for many reasons. The key reason for this phenomenon is the fact that the RH deformity (RHD) is mainly due to the asymmetric development of the ribs and much less so due to the rotation of the vertebrae in the thoracic spine. Surgery on the spine cannot limit the asymmetry of the ribs or stop the mechanism that causes their asymmetrical growth. The results presented in all the reviewed articles support the important protagonistic role of RHD on scoliogenesis, which precedes the subsequent formed spinal deformity.

Coccidioidomycosis Osteoarticular Dissemination.

Valley fever or coccidioidomycosis is a pulmonary infection caused by species of Coccidioides fungi that are endemic to California and Arizona. Skeletal coccidioidomycosis accounts for about half of disseminated infections, with the vertebral spine being the preferred site of dissemination. Most cases of skeletal coccidioidomycosis progress to bone destruction or spread to adjacent structures such as joints, tendons, and other soft tissues, causing significant pain and restricting mobility. Manifestations of such cases are usually nonspecific, making diagnosis very challenging, especially in non-endemic areas. The lack of basic knowledge and research data on the mechanisms defining susceptibility to extrapulmonary infection, especially when it involves bones and joints, prompted us to survey available clinical and animal data to establish specific research questions that remain to be investigated. In this review, we explore published literature reviews, case reports, and case series on the dissemination of coccidioidomycosis to bones and/or joints. We highlight key differential features with other conditions and opportunities for mechanistic and basic research studies that can help develop novel diagnostic, prognostic, and treatment strategies.

Automatic type Identification of Sub - Axial Vertebral Column Fractures using Deep learning Technique

Traumas like falls, sports injuries, or vehicle accidents are the main causes of Vertebral Column Fracture(VCFs) or spine fracture. The symptoms of VCF include back pain, swelling, numbness, and height decrease. VCF causes extreme pain, paralysis, difficulty in movement, etc. CT scans are inexpensive and effective in providing precise and quick VCF type detection. The determination of type VCF, however subject to inter-observer variability. To address this limitation this work introduces an automatic system for the detection of VCF type based on an ensemble of deep fine tuned models. This can assist the orthopaedicians in type identification of VCF which decreases the image interpretation time and increases the patient care time. For type identification, a total of two fine-tuned CNN architectures are used. Then, to further enhance the type identification performance, we developed an ensemble model of fine tuned VGG16 and ResNet50 deep learning models, which average the outputs of the models during final prediction. We used a dataset of 2820 CT images from eight different VCF types that were collected from Kasturba Medical college, Manipal Academy of Higher education, Manipal. The results shows that the ensemble model performs well compare to individual fine-tuned models with accuracy of 82%, precision of 0.84, recall of 0.82 and F1-score of 0.81 for VCF type identification from CT scans. This study shows that type identification of VCF in CT scans may be successfully accomplished using an ensemble deep transfer learning system with various fine tuned CNN architectures.

Rethinking U-Net Deep Neural Network for Spine Radiographic Images-Based Spine Vertebrae Segmentation

Rethinking U-Net Deep Neural Network for Spine Radiographic Images-Based Spine Vertebrae Segmentation

Extended Field Radiosurgery of Spinal Metastases with MRI-Guided Adaptive Planning: A Dosimetric Study

Spinal metastases occur in ∼40% of cancer patients. Stereotactic body radiotherapy (SBRT) precisely delivers high doses of RT to enhance local control and reduce chronic pain. Eligibility for spine SBRT can depend on number of spine vertebrae involved. For example, RTOG 0631 was limited to two contiguous levels due to concerns about spinal cord (SC) tolerance when aligning to long targets in the mobile spine. The purpose of this study was to determine whether adaptive replanning on an MRI-Linear Accelerator could permit SBRT of longer spinal segments. We randomly selected ten patients treated in the abdomen on a 0.35T MRI-Linac with MRI including L2-T8. For each patient, their simulation MRI was used to generate six distinct plans starting at 2 spinal levels incrementing to 7 spinal levels. Coverage was 90% at 16 Gy to the entire vertebrae including processes and TG-101 constraints were used for SC and other nearby organs at risk (OAR). Each plan was then rigidly fused in 6-dimensions to a treatment MRI obtained on another day (non-adaptive) and evaluated. An adaptive plan was then generated for each non-adaptive plan. Target coverage between non-adaptive and adaptive techniques was compared using paired t tests. McNemar's tests were used to compare proportions of dose objective failures for OAR between sets. The target-coverage and number of patients meeting V10 Gy <0.35 and Dose max <14 Gy are shown in the table below with respective p-values. Statistically significant p-values (<0.05) were obtained for all criteria analyzed, especially above 4 vertebral body (VB) levels. This dosimetric analysis suggests that adaptive replanning using a hybrid MR/Linac platform has the potential to safely extend spine SRS beyond the currently accepted practice of 2-3 consecutive VB levels. Future directions include applying this innovative approach in a clinical trial.

Neurologic pathologies of the vertebral spine.

At some institutions, musculoskeletal and general radiologists rather than neuroradiologists are responsible for reading magnetic resonance imaging (MRI) of the spine. However, neurological findings, especially intrathecal ones, can be challenging. Intrathecal neurological findings in the spine can be classified by location (epidural, intradural extramedullary, and intramedullary) or etiology (tumor, infection, inflammatory, congenital). In this paper, we provide a succinct review of the intrathecal neurological findings that can be seen on MRI of the spine, primarily by location and secondarily by etiology, in order that this may serve as a helpful guide for musculoskeletal and general radiologists when encountering intrathecal neurological pathologies.

Biomechanical Evaluation of an Adaptive-Motion Pedicle Screw Fixation System: Experimental and Numerical Analysis.

Rigid fixation is mostly used in thoracolumbar spine surgery, which restricts the thoracolumbar spine segments moving and is not conducive to postoperative rehabilitation. We developed an adaptive-motion pedicle screw and established a finite element model of the T12-L3 segments of the thoracolumbar spine in osteoporosis patients based on the CT image data. A variety of internal fixation finite element models were established for mechanical simulation analysis and comparison. The simulation results showed that compared with the conventional internal fixation system, the mobility of the new adaptive-motion internal fixation system was improved by about 13.8% and 7.7% under the classic conditions such as lateral bending and flexion. in vitro experiments were conducted simultaneously with fresh porcine thoracolumbar spine vertebrae, and the axial rotation condition was taken as an example to analyze the mobility. The in vitro results showed that the mobility of the adaptive-motion internal fixation system had better mobility characteristics under axial rotation conditions, which was consistent with the finite element analysis. The adaptive-motion pedicle screws can preserve a certain degree of vertebral mobility, and avoid excessive vertebral restriction. It also increases the stress value of the intervertebral disk, which is closer to the normal mechanical transmission of the human body, avoiding stress masking and slowing down the degeneration of the intervertebral disk. The adaptive-motion pedicle screws can reduce the peak stress of the implant and avoid surgical failure due to implant fracture.

Plane invariant segmentation of computed tomography images through weighted cross entropy optimized conditional GANs in compressed formats.

Computed tomography (CT) scan provides first-hand knowledge to doctors to identify an ailment. Deep neural networks help enhance image understanding through segmentation and labeling. In this work, we implement two variants of Pix2Pix generative adversarial networks (GANs) with varying complexities of generator and discriminator networks for plane invariant segmentation of CT scan images and subsequently propose an effective generative adversarial network with a suitably weighted binary cross-entropy loss function followed by image processing layer necessary for getting high-quality output segmentation. Our conditional GAN is powered by a unique set of an encoder-decoder network that coupled with the image processing layer produces enhanced segmentation. The network can be extended to the complete set of Hounsfield units and can also be implemented on smartphones. Furthermore, we also demonstrate effects on accuracy, F-1 score, and Jaccard index by using the conditional GAN networks on the spine vertebrae dataset, thus achieving an average of 86.28 % accuracy, 90.5 % Jaccard index score, and 89.9 % F-1 score in predicting segmented maps for validation input images. In addition, an overall lifting of accuracy, F-1 score, and Jaccard index graph for validation images with better continuity has also been highlighted.

Bone analysis using an aggregation‐induced emission‐active iridium complex

AbstractFluorescent analysis of bone provides valuable insights into bone structures. However, conventional dyes suffer from low specificity on bone tissue, small stokes shift, short fluorescent lifetime, and aggregation‐caused quenching effect, which result in low efficacy and artifacts. In this work, we design an aggregation‐induced emission (AIE)‐active iridium(III) complex (Ir‐BP2) as a highly selective, convenient, nondestructiveness, and dual‐mode staining agent for bone analysis. Ir‐BP2 containing phosphonate groups selectively binds to hydroxyapatites, the main component of bone matrix, and exhibits turn‐on AIE phosphorescence with prolonged lifetime. Ir‐BP2 exhibits promising biosafety and offers higher accuracy in staining calcium deposits than conventional Alizarin Red S staining assay when it is employed in real‐time monitoring of osteogenesis differentiation process. A ready‐to‐use staining spray of Ir‐BP2 is fabricated. By using fluorescent imaging and lifetime imaging, Ir‐BP2 staining provides valuable insights into bone microstructure analysis, microdamage diagnosis, and bone growth state identification. Further, Ir‐BP2 is successfully applied on a human spine vertebra for diagnosing bone invasiveness of eosinophilic granuloma, validating its clinical practice. This work presents a powerful tool in bone analysis and will lead to new approaches for the diagnosis and treatment of bone‐related diseases.

Extramedullary plasmacytoma presenting as a rapidly growing lateral neck mass: A case report

Introduction: We detail the rare clinical presentation of an extramedullary plasmacytoma as a rapidly growing lateral neck mass. The pathology and its management are discussed. A rapidly growing extramedullary plasmacytoma infiltrating the cervical spine. Case Report: A 53-year-old male presented to our emergency room with a one-month history of worsening left-sided neck pain and an enlarging lateral neck mass. Evaluation with cervical imaging and laboratory analysis were performed. The patient underwent a soft tissue biopsy with subsequent spinal cord decompression and an occipital-cervical fusion. Pathology revealed the diagnosis of plasmacytoma. The patient was referred to oncology and radiation therapy for adjuvant treatment. Conclusion: This case represents the unusual presentation of a rapidly growing extramedullary plasmacytoma to the soft tissues of the neck with subsequent erosion of the base of the skull and upper cervical vertebral spine. It was treated effectively with posterior cervical decompression, arthrodesis, and adjuvant radiation and chemotherapy.

Functional division and age differences in cervical spine of males and females

Introduction. The cervical spine from osteopathy point of view, taking into account spine functional division, includes vertebrae of the cervical-thoracic junction, and the approach requires additional coordination. The X-ray examination experience with the entire spine integrity suggests that both cervical vertebrae and vertebrae of cervical-thoracic junction are the place of the greatest age-related changes. The study of gender difference in cervical spine vertebra positions and its age-related dynamics requires additional attention. The purpose of the work: on the basis of digital radiographs to develop an integral indicator for assessing the position of the vertebrae of the middle cervical spine; research objectives: to quantify vertebra positions from CIII–VI; to propose a characteristic of transition smoothness from vertebral CIII–VI group to the vertebral CVII–TIII group; to study the male/female features of age trend in cervical spine shape.Materials and methods. Radiographs of all spine parts in sagittal plane were examined for 141 patients with dorsopathies (57 males and 84 females). The cohort of patients is divided into 4 groups: I (n=31) — 21–44 years (average age 33,1 years); II (n=39) — 45–59 years (average age 52,6 years); III (n=50) — 60–74 years (average age 66,8 years); IV (n=21) — 75–88 years (average age 81,1 years). A single digital X-ray spine image in sagittal plane was obtained for each patient. On the combined digital radiograph, the occipital vertical was drawn along all spine parts, starting from the external tubercle of occipital bone, and anteroposterior axes for CIII–TIII vertebrae (r axes) were drawn. The angles between the occipital vertical and the perpendiculars restored to the axes at the points of their intersection with the occipital vertical were measured. Statistical processing of the data obtained was carried out.Results. The St integral indicator has been developed to quantify the vertebra position of middle cervical spine. It was calculated by formula St = (rCIII+rCIV+rCV +rCVI)/4. Using St the type boundaries are determined, and four displacement types for the cervical vertebra group (from CIII–VI) are identifi ed: I — low start; II — medium start; III — high start; IV — ultra-high start. An age-related trend of changes in CIII–VI vertebra position was detected. The correlation between the position indicator St of the middle cervical vertebrae and indicator ArCT for the vertebrae of cervical-thoracic junction CVII–TIII was proved. Gender differences depending on age were revealed in transition smoothness between these spine parts.Conclusion. Some arguments have been obtained confi rming the validity of attributing the vertebra group of cervical-thoracic junction from CVII to TIII to the functional unity of cervical spine. Quantitative smoothness assessment of transition from the middle cervical spine to the vertebra group of cervical-thoracic junction can be carried out by calculating the difference between the ArCT and St indicators. The difference demonstrates age-related shape features of the spine part for males and females.

Predicting the anterior slippage of vertebral lumbar spine using Densenet-201

Lumbar spine illnesses have become more widespread in recent years due to sedentary lifestyles, accidents, and lifestyle changes. Spondylolisthesis is the most common illness, accounting for 5% of all cases worldwide. Both abnormalities can occur in children while they are very young and, if disregarded, can progress to agonizing pain. As a result, early detection can facilitate the implementation of therapies and interventions and halt the disease's spread. This investigation uses radiography scans to determine if any anterior slippage of the lumbar spine's vertebrae exists. This paper suggests a sequential approach to processing data and classifying lumbar spine pictures using deep learning's DenseNet 201, which can efficiently distinguish between normal and Lumbar Spine Anterior Slippage radiography images. Lumbar spine radiograph images are processed with is proven by comparing with conventional preprocessing. The Shah Orthopedic Hospital in Miraj is where the datasets were gathered, which consisted of both the front and side radiological images of the lumbar spine. The result with 30 epochs demonstrates that the DenseNet201 model produces the highest accuracy. The method's Accuracy, Sensitivity, Specificity, & precision are 95.17%, 96.51%, 89.23%, and 93.51%, respectively. According to the comparative data, our technique got the maximum accuracy compared to the other methods.

Joint effects of phenol, chlorophenol pesticide, phthalate, and polycyclic aromatic hydrocarbon on bone mineral density: comparison of four statistical models.

Exposure to phenols, phthalates, pesticides, and polycyclic aromatic hydrocarbons (PAHs) can harm the skeleton. However, data about the joint effects of these chemicals' mixture on bone health are limited. The final analysis involved 6766 participants aged over 20 years recruited from the National Health and Nutrition Examination Survey. Generalized linear regression, weighted quantile sum (WQS) regression, Bayesian kernel machine regression (BKMR), and quantile g-computation (qgcomp) were performed to investigate the association of the urinary levels of chemicals (three phenols, two chlorophenol pesticides, nine phthalates, and six polycyclic aromatic hydrocarbon [PAH] metabolites) with bone mineral density (BMD) measurements and osteoporosis (OP) risk. Generalized linear regression identified that benzophenone-3, 2,4-dichlorophenol, mono-n-butyl phthalate, 1-napthol, 3-fluorene, 2-fluorene, and 1-phenanthrene were significantly associated with lower BMD and increased OP risk. The WQS index was negatively associated with total femur, femoral neck, and lumbar spine vertebra 1 (L1) BMD among all the participants, with corresponding β (95% confidence interval) values of -0.028 g/cm2 (-0.040, -0.017), -0.015 g/cm2 (-0.025, -0.004), and -0.018 g/cm2 (-0.033, -0.003). In the BKMR analysis, the overall effect of the mixture was significantly associated with femoral neck BMD among males and OP risk among females. The qgcomp model found a significant association between co-exposure and L1 BMD among all the participants and among males. Our study presents compelling epidemiological evidence that co-exposure to phenols, chlorophenol pesticides, phthalates, and PAHs is associated with reduced BMD and elevated OP risk. It provides epidemiologic evidence for the detrimental effects of these chemicals on bone health.

Osteosarcopenia in acromegaly: reduced muscle quality and increased vertebral fat deposition.

Musculoskeletal disorders are among the most disabling comorbidities in patients with acromegaly. This study examined muscle and bone quality in patients with acromegaly. Thirty-three patients with acromegaly and nineteen age- and body mass index-matched healthy controls were included in the study. Body composition was determined using dual-energy X-ray absorptiometry. The participants underwent abdominal magnetic resonance imaging (MRI) for cross-sectional evaluation of muscle area and vertebral MRI proton density fat fraction (MRI-PDFF). Muscular strength was measured using hand grip strength (HGS). Skeletal muscle quality (SMQ) was classified as weak, low, or normal, according to HGS/ASM (appendicular skeletal muscle mass) ratio. Groups had similar lean tissues, total body fat ratios, and total abdominal muscle areas. Acromegalic patients had lower pelvic BMD (p = 0.012) and higher vertebral MRI-PDFF (p = 0.014), while total and spine bone mineral densities (BMD) were similar between the groups. The SMQ score rate was normal only 57.5% in the acromegaly group, and 94.7% of the controls had a normal SMQ score (p = 0.01). Subgroup analysis showed that patients withactive acromegaly (AA) had higher lean tissue and lower body fat ratios than controlled acromegaly (CA) and control groups. Vertebral MRI-PDFF was higher in the CA group than that in the AA and control groups (p = 0.022 and p = 0.001, respectively). The proportion of participants with normal SMQ was lower in the AA and CA groups than that in the control group (p = 0.012 and p = 0.013, respectively). Acromegalic patients had reduced SMQ and pelvic BMD, but greater vertebral MRI-PDFF. Although lean tissue increases in AA, this does not affect SMQ. Therefore, increased vertebral MRI-PDFF in controlled acromegalic patients may be due to ectopic adiposity.

Prediction of low DEXA T-scores by routine computed tomography body scans at different kilovoltage peaks.

Previous studies have demonstrated positive correlations between computed tomography (CT) attenuation of lumbar spine vertebrae and their bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DEXA). However, these studies were performed using a standard 120 kilovoltage peak (kVp) setting. As radiation attenuation in mineralised tissues varies by the tube voltage applied, we determined the diagnostic accuracy of CT attenuation at identifying individuals with low BMD at different kVp settings. Single centre retrospective study of adults who had CT and DEXA scans within 6 months of each other. CT scans were performed at either 100 kVp, 120 kVp or dual energy (80 kVp/140 kVp). Attenuation was measured in axial cross-sections of L1-4 vertebrae and correlated with the results of DEXA. Receiver operated characteristic (ROC) curves were generated to determine diagnostic cut-off thresholds. Analysis included 268 subjects (169 females; mean age: 70, range: 20-94 years). CT attenuation values at L1 or mean L1-4 correlated positively with DEXA-derived T-scores. At L1, the optimal Hounsfield units (HU) thresholds for predicting DEXA T-scores of -2.5 or less at 100 kVp, 120 kVp and dual-energy scans were <170, <128 and <164, with corresponding AUCs of 0.925, 0.814 and 0.743 respectively. For mean L1-4, the HU thresholds were <173, <134 and <151, with corresponding AUCs of 0.933, 0.824 and 0.707 respectively. CT attenuation thresholds differ depending on the tube voltage used. We provide voltage-specific, probability-optimised thresholds for the identification of persons likely to have low BMD on DEXA scanning.

Accuracy of Ultrasound-Guided Needle Placement on the L5 Lumbar Nerve Root: A Cadaveric Study.

The aims of the study are to analyze and describe the accuracy of an ultrasound-guided approach to target the L5 root in cadaveric specimens and evaluate whether gender differences exist. A cross-anatomical study on 40 cadaver L5 nerve roots was performed. A needle was introduced until contacting the L5 nerve root using ultrasound guidance. After that, specimens were frozen and studied by a cross-anatomical view to see the needle's path. The angulation, length, distance from the vertebral spine, the relevant ultrasound anatomical references, and the accuracy of the procedure were evaluated. The needle tip reached the L5 root at a 72.5% rate. The mean angulation degrees of the needle relative to the skin surface were 75.53 ± 10.17 degrees, the length of the needle inserted was 5.83 ± 0.82 cm, and the distance from the vertebral spine to the point of entry of the needle was 5.39 ± 1.44 cm. An ultrasound-guided technique can potentially be an accurate technique to perform invasive procedures on the L5 root. There were statistically significant differences between males and females in the length of the needle introduced. If the L5 root is not clearly visualized, ultrasound will not be the technique of choice.

Craniofacial Microsomia: New Updates in Spinal Anomalies.

Craniofacial microsomia (CFM) involves anomalies of the first and second pharyngeal arches, mainly of the mandible, maxilla, ears, and vertebral spine. This study aimed to identify the frequency and morphology of spinal anomalies of individuals with clinical diagnoses of CFM. In addition, the correlation between spinal anomalies and craniofacial involvement was performed. This study was a retrospective review of individuals with a clinical diagnosis of craniofacial microsomia. The inclusion criteria were a clinical diagnosis of CFM with no overlap with any other syndromes of first and second pharyngeal arches and radiograph availability in the hospital's database. Prevalence and morphology of spinal anomalies were calculated and clinical details were recorded: types of spinal anomalies and correlations according to OMENS score. The sample consisted of 46 individuals with a clinical diagnosis of CFM, 24 (52,2%) female and 22 (47,8%) male (1M:1F). Twenty-one (45,7%) had unilateral craniofacial involvement and 25 (54,3%), bilateral. Twenty-eight (60,9%) individuals presented spinal anomalies. Those with unaltered spinal morphology showed a slight preference toward OMENS scores under 5: 7 patients did, only one of which had spinal alterations (14,3%); 68,8% (22) in the group with scores 5 to 9 (n=32) and 71,4% (5) in the 10 to 15 group (n=7) did as well. Spinal anomalies in individuals with CFM are more common than usually reported in medical literature, mainly when associated with radial anomalies and correlate with statistical significance to facial features, mainly the OMENS score.

Sweeping Surfaces according to Type-3 Bishop Frames in Euclidean 3-Space

The aim of this work is to investigate sweeping surfaces and their local singularities due to type-3 Bishop frames in Euclidean 3-space, E3. A sweeping surface a is surface that is designed from a section curve positioned along a path, which acts as the vertebral column or spine curve, and it has symmetrical characteristics. In this work, we have specified a sweeping surface and have examined its geometry and singularity. Thereafter, we deduced the circumstances required for this surface to be a developable surface. In great detail, we concentrated on the fundamental discussion on whether the resulting developable surface is a cylindrical, cone or tangent surface. Meanwhile, examples are detailed to explain the applications of the notional outcomes.

Clinical outcomes of the traditional dual growing rod technique combined with apical pedicle screws in the treatment of early-onset scoliosis: preliminary results from a single center.

Limited control of an apical deformity is a major disadvantage in the traditional dual growing rod (TDGR) technique. Previous literature has reported the results of apical pedicle screw placement (APS) as an apical control technique in patients with early-onset scoliosis (EOS). However, the clinical outcomes, indications, and complications of the TDGR technique combined with APSs have not been well described. The purpose of this study was to evaluate the preliminary clinical outcomes of the TDGR technique combined with APSs in EOS patients. Clinical data of 12 patients with EOS who were treated with the TDGR technique combined with APSs at the index surgery at the authors' center from January 2010 to January 2020, with a minimum 2-year follow-up, were retrospectively reviewed. Indications for the use of APSs included 1) no vertebral segmentation failure, fused ribs, or multiple hemivertebrae at the apex; 2) at least 2 normal discs around the apex; and 3) proper development of apical pedicles on the convex side. Etiology, age at index surgery, number of lengthening procedures, follow-up duration, and complications were recorded. Radiographic measurements included Cobb angle, apical vertebral translation (AVT), apical vertebral rotation (AVR), thoracic kyphosis, lumbar lordosis, spine height, and space available for the lung (SAL). The mean follow-up period was 4.0 ± 1.4 years, with a mean of 4.8 lengthening procedures per patient. The mean Cobb angle improved from 61.7° ± 10.4° to 19.9° ± 9.0° after the index surgery (19.6° ± 9.4° at the latest follow-up). The mean postindex AVT decreased to 16.8 ± 8.9 mm from a preindex AVT of 56.3 ± 9.7 mm and further improved to 13.6 ± 10.0 mm at the latest follow-up. The mean annual increases in T1-12 and T1-S1 height were 9.0 ± 4.7 mm and 13.9 ± 6.5 mm, respectively. The SAL improved from 0.91 to 1.04 at the latest follow-up. AVR improved significantly after the index surgery (p = 0.013), while minor deterioration was observed after repeat lengthening procedures. Five complications (2 implant related and 3 alignment related) occurred in 4 patients. For EOS patients with good flexibility (without segmentation failure or multiple hemivertebrae at the apex), the TDGR technique combined with APSs can improve primary curve correction, maintain good correction results, and allow continuous spine growth, which may reduce the risks of complications during lengthening treatment. More multicenter prospective studies with larger samples are needed to further validate the findings of this study.

Predicting spinal column profile from surface topography via 3D non-contact surface scanning.

3D Non-Contact surface scanning (3DSS) is used in both biomechanical and clinical studies to capture accurate 3D images of the human torso, and to better understand the shape and posture of the spine-both healthy and pathological. This study sought to determine the efficacy and accuracy of using 3DSS of the posterior torso, to determine the curvature of the spinal column in the lateral lying position. A cohort of 50 healthy adults underwent 3DSS and Magnetic Resonance Imaging (MRI) to correlate the contours of the external spine surface with the internal spinal column. The correlation analysis was composed of two phases: (1) MRI vertebral points vs MRI external spine surface markers; and (2) MRI external spine surface markers vs 3DSS external spine surface markers. The first phase compared the profiles of fiducial markers (vitamin capsules) adhered to the skin surface over the spinous processes against the coordinates of the spinous processes-assessing the linear distance between the profiles, and similarity of curvature, in the sagittal and coronal planes. The second phase compared 3DSS external spine surface markers with the MRI external spine surface markers in both planes, with further qualitative assessment for postural changes. The distance between the MRI vertebral points and MRI external spine surface markers showed strong statistically significant correlation with BMI in both sagittal and coronal planes. Kolmogorov-Smirnov (KS) tests showed similar no significant difference in curvature, k, in almost all participants on both planes. In the second phase, the coronal 3DSS external spine surface profiles were statistically different to the MRI external spine surface markers in 44% of participants. Qualitative assessment showed postural changes between MRI and 3DSS measurements in these participants. These study findings demonstrate the utility and accuracy of using anatomical landmarks overlaid on the spinous processes, to identify the position of the spinal bones using 3DSS. Using this method, it will be possible to predict the internal spinal curvature from surface topography, provided that the thickness of the overlaying subcutaneous adipose layer is considered, thus enabling postural analysis of spinal shape and curvature to be carried out in biomechanical and clinical studies without the need for radiographic imaging.