Thoracic Cage Deformity Correction in Patients with Lenke Type 1 Adolescent Idiopathic Scoliosis.

Whether the thoracic cage deformity in adolescent idiopathic scoliosis (AIS) can be sufficiently treated with vertebral derotation alone, has been quite controversial. Our aim is to control the hypothesis that the rib cage deformity (RCD) may be adequately corrected when only vertebral derotation is applied. We studied retrospectively patients treated for AIS with posterior spinal fusion without costoplasty. The RCD was assessed on lateral radiographs by rib index (RI). The correction of RI after surgery was calculated. Of the 103 patients that were finally included in our study, 29 patients (22 females and 7 males; mean age, 14.5 ± 2.1 years) represented Group A (Harrington rod instrumentation - no derotation), while 74 patients (61 females and 13 males; mean age, 14.1 ± 2.4 years) were operated with either a full pedicle screw system or a hybrid construct with hooks and pedicle screws (Group B-derotation). RI was significantly corrected after surgery in both groups. RI was significantly greater in Group A after surgery. Whatsoever, the correction of RI, thereby the RCD correction, did not significantly differ among groups. In conclusion, it cannot be suggested by the present study that vertebral derotation alone can offer an absolute correction of the deformity of the thoracic cage in patients with Lenke Type 1 AIS, and it seems also that the development of RCD may not exclusively result from the spinal deformity, thus questions can be further raised regarding scoliogeny per se.

Assessment of a fully-parametric thoraco-lumbar spine model generator with articulated ribcage.

The present paper describes a novel user-friendly fully-parametric thoraco-lumbar spine CAD model generator including the ribcage, based on 22 independent parameters (1 posterior vertebral body height per vertebra + 4 sagittal alignment parameters, namely pelvic incidence, sacral slope, L1-L5 lumbar lordosis, and T1-T12 thoracic kyphosis). Reliable third-order polynomial regression equations were implemented in Solidworks to analytically calculate 56 morphological dependent parameters and to automatically generate the spine CAD model based on primitive geometrical features. A standard spine CAD model, representing the case-study of an average healthy adult, was then created and positively assessed in terms of spinal anatomy, ribcage morphology, and sagittal profile. The immediate translation from CAD to FEM for relevant biomechanical analyses was successfully demonstrated, first, importing the CAD model into Abaqus, and then, iteratively calibrating the constitutive parameters of one lumbar and three thoracic FSUs, with particular interest on the hyperelastic material properties of the IVD, and the spinal and costo-vertebral ligaments. The credibility of the resulting lumbo-sacral and thoracic spine FEM with/without ribcage were assessed and validated throughout comparison with extensive in vitro and in vivo data both in terms of kinematics (range of motion) and dynamics (intradiscal pressure) either collected under pure bending moments and complex loading conditions (bending moments + axial compressive force).

Real-time changes in rib cage expansion and use of abdominal mechanical stimulation in newborns: a quasi-experimental study.

OBJECTIVE: To assess the rib cage expansion and respiratory rate in newborns using an abdominal stabilization band. METHODS: The study included 32 newborns of both genders, with gestational age between 35 and 41 weeks. The abdominal stabilization band was used for 15 minutes between the xiphoid process and the anterosuperior iliac crest, with an abdominal contention 0.5cm smaller than the abdominal circumference. The rib cage expansion was evaluated by a breathing transducer (Pneumotrace II™) three minutes before using the band, during the use (15 minutes), and ten minutes after removing the band. The Shapiro-Wilk test verified data normality, and the Wilcoxon test compared the variables considering rib cage expansion and respiratory rate. Significance was set to p<0.05. RESULTS: There was an increase in respiratory rate when comparing before and ten minutes after removing (p=0.008) the abdominal stabilization band, as well as when comparing during its use and ten minutes after its removal (p=0.001). There was also an increase in rib cage expansion when comparing before and during the use of the abdominal stabilization band (p=0.005). CONCLUSIONS: The use of the abdominal stabilization band promoted an increase in the rib cage expansion and respiratory rate in the assessed newborns and may be a viable option to improve the respiratory kinematics of this population.

Does in-brace correction affect coronal spinal and thoracic cage parameters in individuals with idiopathic scoliosis? A retrospective cohort study.

The aim of the study is to identify the effects of in-brace correction on coronal spinal and thoracic cage parameters in individuals with idiopathic scoliosis (IS). The coronal spinal parameters [Cobb angle, apical vertebral rotation (AVR), lateral trunk shift, coronal alignment, biacromial slope and pelvic asymmetry] and the thoracic cage parameters [T1- 12 height, T1-S1 height, thoracic transverse diameter, and apical vertebral body-rib ratio (AVB-R)] of 89 child and adolescent patients were measured on posterior-anterior full-spine radiographs at pre-brace and in-brace conditions using Surgimap software. The initial in-brace correction (IBC) was calculated as a percentage decrease in the Cobb angle on the in-brace radiographs. The mean IBC rate for the primary curve was 37% (range = 10-100%). In the in- brace condition, the Cobb angle (p<0.001), AVR (p<0.001) and lateral trunk shift (p<0.001) decreased significantly; no statistically significant difference was found in the biacromial slope (p=0.713) and the coronal alignment (p=0.074). The T1-12 height and the T1-S1 height increased significantly (p<0.001) whereas the thoracic transverse diameter and the AVB-R decreased significantly (p<0.001). Unlike IBC rate was below 30% as IBC rate was above 30%, the T1-12 height (p<0.001) increased and the AVB-R decreased (p<0.001). The bracing improved the lateral trunk shift, the AVB-R, the thoracic and spine heights, but decreased the thoracic transverse diameter. The thoracic cage parameters may be better when the IBC rate is above 30%.

Pulmonary and chest wall function in obese adults.

Obesity is frequently associated with breathing disorders. To investigate if and how the highest levels of obesity impact respiratory function, 17 subjects with obesity (median age: 49 years; BMI: 39.7 kg/m2, 8 females) and 10 normal-weighted subjects (49 years; 23.9 kg/m2, 5 females) were studied. The abdominal volume occupied 41% in the obese group, being higher (p < 0.001) than the normal-weighted group (31%), indicating accumulation of abdominal fat. Restrictive lung defect was present in 17% of subjects with obesity. At rest in the supine position, subjects with obesity breathed with higher minute ventilation (11.9 L/min) and lower ribcage contribution (5.7%) than normal weighted subjects (7.5 L/min, p = 0.001 and 31.1%, p = 0.003, respectively), thus indicating thoracic restriction. Otherwise healthy obesity might not be characterized by a systematic restrictive lung pattern. Despite this, another sign of restriction could be poor thoracic expansion at rest in the supine position, resulting in increased ventilation. Class 3 obesity made respiratory rate further increased. Opto-electronic plethysmography and its thoraco-abdominal analysis of awake breathing add viable and interesting information in subjects with obesity that were complementary to pulmonary function tests. In addition, OEP is able to localize the restrictive effect of obesity.

Crystal ribcage: a platform for probing real-time lung function at cellular resolution.

Understanding the dynamic pathogenesis and treatment response in pulmonary diseases requires probing the lung at cellular resolution in real time. Despite advances in intravital imaging, optical imaging of the lung during active respiration and circulation has remained challenging. Here, we introduce the crystal ribcage: a transparent ribcage that allows multiscale optical imaging of the functioning lung from whole-organ to single-cell level. It enables the modulation of lung biophysics and immunity through intravascular, intrapulmonary, intraparenchymal and optogenetic interventions, and it preserves the three-dimensional architecture, air-liquid interface, cellular diversity and respiratory-circulatory functions of the lung. Utilizing these capabilities on murine models of pulmonary pathologies we probed remodeling of respiratory-circulatory functions at the single-alveolus and capillary levels during disease progression. The crystal ribcage and its broad applications presented here will facilitate further studies of nearly any pulmonary disease as well as lead to the identification of new targets for treatment strategies.

Effect of thoracic cage width on surgery time and postoperative outcome in minimally invasive esophagectomy.

INTRODUCTION: Minimally invasive esophagectomy (MIE) for esophageal cancer is a complex procedure that reduces postoperative morbidity in comparison to open approach. In this study, thoracic cage width as a factor to predict surgical difficulty in MIE was evaluated. METHODS: All patients of our institution receiving either total MIE or robotic-assisted MIE (RAMIE) with intrathoracic anastomosis between February 2016 and April 2021 for esophageal cancer were included in this study. Right unilateral thoracic cage width on the level of vena azygos crossing the esophagus was measured by the horizontal distance between the esophagus and parietal pleura on preoperative computer tomography. Patients' data as well as operative and postoperative details were collected in a prospective database. Correlation between thoracic cage width with duration of the thoracic procedure and postoperative complication rates was analyzed. RESULTS: Overall, 313 patients were eligible for this study. Thoracic width on vena azygos level ranged from 85 to 149 mm with a mean of 116.5 mm. In univariate analysis, a small thoracic width significantly correlated with longer duration of the thoracic procedure (p = 0.014). In multivariate analysis, small thoracic width and neoadjuvant therapy were identified as independent factors for long duration of the thoracic procedure (p = 0.006). Regarding postoperative complications, thoracic cage width was a significant risk factor for occurrence of postoperative pneumonia in the multivariate analysis (p = 0.045). Dividing the cohort into two groups of patients with narrow (≤ 107 mm, 19.5%) and wide thoraces (≥ 108 mm, 80.5%), the thoracic procedure was significantly prolonged by 17 min (204 min vs. 221 min, p = 0.014). CONCLUSION: A small thoracic cage width is significantly correlated with longer operation time during thoracic phase of a MIE in Europe, which suggests increased surgical difficulty. Patients with small thoracic cage width may preferably be operated by MIE-experienced surgeons.

Costal margin injuries and trans-diaphragmatic intercostal hernia: Presentation, management and outcomes according to the Sheffield classification.

BACKGROUND: Costal margin rupture (CMR) injuries are under-diagnosed and inconsistently managed, while carrying significant symptomatic burden. We hypothesized that the Sheffield Classification system of CMR injuries would relate to injury patterns and management options. METHODS: Data were collected prospectively between 2006 and 2023 at a major trauma center in the United Kingdom. Computed tomography scans were interrogated and injuries were categorized according to the Sheffield Classification. Clinical, radiologic, management and outcome variables were assessed. RESULTS: Fifty-four patients were included in the study. Intercostal hernia (IH) was present in 30 patients and associated with delayed presentation ( p = 0.004), expulsive mechanism of injury (i.e. such as occurs with coughing, sneezing, or retching), higher body mass index ( p < 0.001), and surgical management ( p = 0.02). There was a bimodal distribution of the level of the costal margin rupture, with IH Present and expulsive mechanism injuries occurring predominantly at the ninth costal cartilage, and IH Absent cases and other mechanisms at the seventh costal cartilage ( p < 0.001). There were correlations between the costal cartilage being thin at the site of the CMR and the presence of IH and expulsive etiology ( p < 0.001). Management was conservative in 23 and surgical in 31 cases. Extrathoracic mesh IH repairs were performed in 3, Double Layer Mesh Repairs in 8, Suture IH repairs in 5, CMR plating in 8, CMR sutures in 2, and associated Surgical Stabilization of Rib Fractures in 11 patients. There was one postoperative death. There were seven repeat surgical procedures in five patients. CONCLUSION: The Sheffield Classification is associated statistically with presentation, related chest wall injury patterns, and type of definitive management. Further collaborative data collection is required to determine the optimal management strategies. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Tumor de células gigantes óseo en arco costal, tratado con denosumab. Reporte de un caso / Giant cell tumour of bone in the rib cage treated with denosumab. A case report

El tumor de células gigantes óseo (TCGO) representa el 4-5% de los tumores óseos primarios, se localiza en la epífisis de huesos largos, cuerpos vertebrales y huesos planos, y es más frecuente en el sexo femenino entre los 20 y 45 años. Presentamos el caso de una mujer de 31 años con dolor torácico de un mes de evolución. En la exploración física se palpó un nódulo en mama derecha y semiología de derrame pleural ipsilateral. El estudio mediante TAC torácica evidenció una masa infiltrante. La lesión fue biopsiada, permitiendo el diagnóstico de TCGO. Debido a la localización y a la morfología, se planteó un amplio diagnóstico diferencial. Adicionalmente, se detectó la mutación del gen de la histona H3F3A, reforzando el diagnóstico. Recibió tratamiento neoadyuvante con denosumab, haciendo posible la posterior resección quirúrgica de la lesión. En la pieza quirúrgica se observaron cambios histológicos, fuente de pitfalls diagnósticos.(AU)

Giant cell tumour of bone (GCTOB) accounts for 4-5% of all primary bone tumours and occurs most frequently in females between 20 and 45 years old. It is found in the epiphyses of the long bones, vertebral bodies and flat bones.We report the case of a 31-year-old woman who presented with a one month history of thoracic pain. On examination, a mass was found in the right breast with signs of an ipsilateral pleural effusion. A thoracic CAT scan revealed an infiltrating mass which was subsequently biopsied and a GCTOB was diagnosed. Due to the localization and the morphology, a wide range of differential diagnoses were considered. Genetic studies detected a mutation of the gene H3F3A, supporting the original diagnosis. The patient underwent treatment with denosumab followed by surgical resection of the mass. The histopathology of the tumour revealed various histological changes which were a source of diagnostic pitfalls.(AU)

Conventional chondrosarcoma of the rib cage and sternum: clinicopathological and molecular analysis of 27 patients treated at a single institution.

Conventional chondrosarcoma of the chest wall is rare, accounting for 15% of cases. Our purpose was to document clinicopathological, imaging and outcome results from a novel set of chest wall chondrosarcomas, and to analyze for IDH mutations and novel molecular alterations. Gross and microscopic pathology, imaging and clinical charts were reviewed. Targeted next-generation sequencing was performed to identify somatic mutations and copy number alterations. The cohort consisted of 27 patients: 16 men and 11 women (mean age 51 years; range 23-76). Palpable mass was the most common presentation. Five were discovered incidentally. Among 20 tumors with complete imaging, 15 arose from a rib and 5 from the sternum. Seven rib tumors were central/intramedullary, 5 were periosteal, 2 were secondary peripheral chondrosarcomas, and one was indeterminate. Among sternal tumors, 4 were central/intramedullary and one was periosteal. Half the periosteal tumors arose from the costochondral junctional cartilage (CCJ). Periosteal chondrosarcomas were sometimes mistaken for extraskeletal masses on initial clinical or radiological examinations. Fifty-nine percent of all tumors were grade 1 and 41% were grade 2. None were dedifferentiated chondrosarcomas. Heterozygous IDH1 mutation was detected in one tumor and heterozygous RAD50 mutation in another. Local recurrence(s) happened in 41% and metastasis in 41%. Grade had strong association with local recurrence (25% grade 1 vs. 64% grade 2 [P = .0447]), metastatic recurrence (19% grade 1 vs. 73% grade 2 [P = .0058]), and survival. Although chest wall chondrosarcomas share morphologic and molecular features with other chondrosarcomas, there is a much higher incidence of periosteal chondrosarcomas. IDH mutant tumors are uncommon. Early diagnosis and margin-negative resection is treatment of choice since chondrosarcomas are chemo- and radioresistant.

Efficacy of ultrasound-guided bilateral costal margin block in laparoscopy-assisted gastrectomy: A double-blind randomized trial.

BACKGROUND: Ultrasound-guided costal margin block (CMB) is a superficial and easily applicable technique. The current study aims to investigate its analgesic efficacy in patients undergoing laparoscopy-assisted gastrectomy and describe its feasibility. METHODS: Forty-two patients undergoing laparoscopy-assisted gastrectomy were enrolled in this prospective, double-blind, randomized clinical trial. Patients were randomized to receive standard general anesthesia with (block group, n = 21) or without (control group, n = 21) ultrasound-guided bilateral CMB. The primary outcome was 24-h intravenous morphine equivalents after surgery. Secondary outcomes included consumption of titrated morphine, 24-48 h morphine equivalents, consumption of intraoperative remifentanil, numerical pain rating scale scores, time to first opioid dose, patient satisfaction, adverse effects, and recovery events. RESULTS: The postoperative 24-h morphine equivalents in the block group were significantly reduced compared to the control group (14.4 ± 7.4 mg vs. 29.9 ± 9.8 mg, p < 0.001). Both the titrated morphine consumption in the post-anesthesia care unit (PACU) and intraoperative remifentanil consumption were lower in the block group than in the control group. Patients in the block group had relatively lower average pain scores in PACU and reported more satisfaction with pain relief. Adverse effects and hospital length of stay after surgery were comparable between the two groups (p > 0.05). CONCLUSION: As a novel and easily-performed technique, ultrasound-guided bilateral CMB can reduce opioid consumption in patients undergoing laparoscopy-assisted gastrectomy.

The anatomical growth of the thoracic cage in adolescents with specific reference to axial growth comparing the right and left hemithorax.

This study has demonstrated the changing volume of both the anterior and posterior thorax in normal adolescents (without spinal or thoracic deformity), differentiating for both sex and age, to further understand how the thorax grows, along with the differences in growth between the anterior and posterior thorax. The thorax was measured on axial CT slices at every vertebral level from T3 to T12 in a series of scans previous taken for routine clinical care. Measurements taken were the anteroposterior thoracic distance and the area of the anterior and posterior rib prominences on either side of the thorax. Data was analyzed per vertebral level, differentiating for age and sex. There were 486 CT scans analyzed (257 males and 229 females) between the ages of 8 and 18 years. The analysis identified that for the anterior thorax, there are three phases of growth with an initial slow increase in volume, followed by a stabilization of little growth, followed by another phase of a more rapid increase in volume. For the posterior thorax, there was a gradual increase in area with increasing age. This study demonstrates that the shape of the thorax is age and sex dependent, with males having both a greater width and depth of thorax compared to females. Of particular note is the difference in patterns of growth between the anterior and posterior thorax. This information will add to the understanding of normal growth, which will aid in the management of conditions where that growth is disturbed.

A rare unreported bilateral thoracic muscle on the inferior and posteromedial aspect of the rib cage: case report and literature review.

Thoracic wall muscles are essential for respiration. Few anatomical variations in thoracic wall muscles have been reported. Such variants must be considered during surgical procedures that involve the thorax muscles. During routine dissection of a 65-year-old male cadaver as part of a fourth-year clinical anatomy elective, additional muscle strips were found in the inner and inferior aspect of the rib cage closer to the posteromedial body wall. The muscle consisted of two strips of narrow muscle fibres originating from the inferior borders of ribs 11 and 12 that radiated to insert on the transverse processes of the T11 and T12 vertebrae. The case report describes an unusual, novel medial thoracic wall muscle that has not been previously described in the literature. Variations in thoracic muscles can affect respiratory function and surgical interventions like chest tube placement and needle therapy for local anaesthesia, therefore, it is important for clinicians to be aware of such variants.

Tuberculosis of the ribcage by dissemination of Koch bacilli.

INTRODUCTION: Tuberculosis (TB) is an infectious, transmissible and immune disease caused by the Mycobacterium tuberculosis-complex (MTBC). Although osteoarticular tuberculosis (OATB) has been widely described, the ribcage variety remains a rare form. CASE REPORT: A thirteen-month-old male and a twenty-month-old female, both with pain and increased volume of anterolateral left rib cage were described. Physical examination revealed the presence of a soft consistent mass at the level of the 9th and 5th costal arches in the male and female patients respectively. Upon clinical evaluation, tuberculosis was suspected, which was confirmed by X-ray and histopathological studies. After confirmation, the management, based on anti-tuberculosis therapy was started as follows: nine months of anti-tuberculosis therapy for the male patient and fourteen months for the female. The outcomes were favorable for both patients. However, further interventions, consisting of abscess drainage in the male patient and excisional biopsy in the female patient were necessary. With these therapeutic interventions, to date, the patients are without any evidence of active TB.

Experience of the Wang procedure in treating pectus excavatum in two hundred fifty-six paediatric patients.

INTRODUCTION: To analyze and summarize the orthopaedic effect and application experience of the Wang procedure in the treatment of pectus excavatum in paediatric patients. METHODS: The clinical data of 256 children ranging from 0.83~14 years (4.89±2.83 years) who underwent the Wang procedure for pectus excavatum from January 2017 to September 2020 in our hospital were analyzed retrospectively. A 1~2-cm incision was made in front of the xiphoid, and a tunnel was constructed on the deep surface of the thoracic cage. Steel wires were inserted through the bilateral costal arch and the lower sternum, and a steel bar was placed in the tunnel. The wires were pulled taut and fixed to the bar, and the incision was sutured. RESULTS: All the procedures were performed using one steel bar. The range of the procedure duration, the intra-operative bleeding volume, and the hospitalization stays of the patients were 18 to 45 (24.02±4.89) minutes, one to ten (2.16±1.68) mL, and three to nine days (5.71±1.35 days) respectively. Post-operative pneumothorax occurred in three cases without other complications. All the cases received follow-up for one to 45 months after discharge, during which six cases experienced poor wound healing, removed steel plate in 82 cases, and three cases of pectus excavatum recurrence. CONCLUSIONS: The Wang procedure is a good option for treating pectus excavatum, secondary pectus excavatum, or recurrent pectus excavatum in paediatric patients.

A deep look into the rib cage compression technique in mechanically ventilated patients: a narrative review. / Desvendando a técnica de compressão torácica em pacientes em ventilação mecânica: uma revisão narrativa.

Defective management of secretions is one of the most frequent complications in invasive mechanically ventilated patients. Clearance of secretions through chest physiotherapy is a critical aspect of the treatment of these patients. Manual rib cage compression is one of the most practiced chest physiotherapy techniques in ventilated patients; however, its impact on clinical outcomes remains controversial due to methodological issues and poor understanding of its action. In this review, we present a detailed analysis of the physical principles involved in rib cage compression technique performance, as well as the physiological effects observed in experimental and clinical studies, which show that the use of brief and vigorous rib cage compression, based on increased expiratory flows (expiratory-inspiratory airflow difference of > 33L/minute), can improve mucus movement toward the glottis. On the other hand, the use of soft and gradual rib cage compression throughout the whole expiratory phase does not impact the expiratory flows, resulting in ineffective or undesired effects in some cases. More physiological studies are needed to understand the principles of the rib cage compression technique in ventilated humans. However, according to the evidence, rib cage compression has more potential benefits than risks, so its implementation should be promoted.

O manejo deficiente das secreções é uma das complicações mais frequentes em pacientes em ventilação mecânica invasiva. A depuração das secreções por meio da fisioterapia respiratória é um aspecto crítico do tratamento desses pacientes. A compressão torácica manual é uma das técnicas de fisioterapia respiratória mais praticadas em pacientes ventilados, mas seu impacto nos desfechos clínicos permanece controverso devido a questões metodológicas e ao pouco conhecimento sobre sua ação. Nesta revisão, apresenta-se uma análise detalhada dos princípios físicos envolvidos na execução da técnica de compressão torácica. Também investigam-se os efeitos fisiológicos observados em estudos experimentais e clínicos, que mostram que o uso de compressão torácica curta e vigorosa, baseada no aumento de fluxos expiratórios (diferença de fluxo aéreo inspiratório-expiratório > 33L/minuto), pode melhorar o movimento do muco em direção à glote. Por outro lado, o uso de compressão torácica suave e gradual ao longo de toda a fase expiratória não afeta os fluxos expiratórios, resultando em efeitos ineficazes ou indesejados em alguns casos. Mais estudos fisiológicos são necessários para entender os princípios da técnica de compressão torácica em pacientes ventilados. No entanto, de acordo com as evidências, a compressão torácica tem mais benefícios potenciais do que riscos, o que incentiva sua implementação.

The rib cage: a new element in the spinopelvic chain.

INTRODUCTION: This study analyzes anatomical variations of the thoracic cage (TC) according to spinopelvic alignment, age and gender using stereoradiography in erect position. METHODS: This retrospective multicentric study analyzed computed parameters collected from free-standing position bi-planar radiographs, among healthy subjects. Collected data were: age, gender, pelvic parameters (Pelvic Incidence, Pelvic Tilt (PT) and Sacral Slope), T1-T12 Kyphosis (TK), L1-S1 Lordosis (LL), curvilinear spinal length, global TC parameters (maximum thickness and width, rib cage volume, mean Spinal Penetration Index (SPI)), 1st-10th rib parameters (absolute and relative (to the corresponding vertebra) sagittal angles). RESULTS: Totally, 256 subjects were included (140 females). Mean age was 34 (range: 8-83). Significant correlations were found between TK and TC thickness (0.3, p < 0.001) and with TC Volume (0.3, p = 0.04), as well as rib absolute sagittal angle for upper and middle ribs (0.2, p = 0.02). Conversely, a -0.3 correlation has been exhibited between SPI and TK. Similar correlations were found with LL. PT significantly correlated with TC thickness (0.4, p = 0.003), SPI (-0.3, p = 0.03), and all rib relative sagittal angles. Among global TC parameters, only thickness and SPI significantly changed after 20 years (respectively, 0.39 and -0.52, p < 0.001). Ribs relative sagittal angle showed negative correlation with age in skeletally mature subjects (p < 0.001). CONCLUSION: This study demonstrates the correlation between TC anatomy and spinopelvic parameters, confirming its part of the spinopelvic chain of balance. Indeed, higher spinal curvatures were associated with lower SPI and higher TC thickness, TC volume and rib absolute sagittal angles.

Development of a Finite Element Model of the Pediatric Thoracic and Lumbar Spine, Ribcage, and Pelvis With Orthotropic Region-Specific Vertebral Growth.

Finite element (FE) modeling of the spine has increasingly been applied in orthopedic precision-medicine approaches. Previously published FE models of the pediatric spine growth have made simplifications in the geometry of anatomical structures, material properties, and representation of vertebral growth. To address those limitations, a comprehensive FE model of a pediatric (10-year-old) osteo-ligamentous thoracic and lumbar spine (T1-L5 with intervertebral discs (IVDs) and ligaments), ribcage, and pelvis with age- and level-specific ligament properties and orthotropic region-specific vertebral growth was developed and validated. Range of motion (ROM) measures, namely, lateral bending, flexion-extension, and axial rotation, of the current 10 YO FE model were generally within reported ranges of scaled in vitro adult ROM data. Changes in T1-L5 spine height, as well as kyphosis (T2-T12) and lordosis (L1-L5), angles in the current FE model for two years of growth (from ages 10 to 12 years) were within ranges reported from corresponding pediatric clinical data. The use of such comprehensive pediatric FE models can provide clinically relevant insights into normative and pathological biomechanical responses of the spine, and also contribute to the development and optimization of clinical interventions for spine deformities.