How to make a digital reconstruction of the human ribcage.

Up to now, there have been no publication standardizing the digital reconstruction of the modern human ribcage from commingled costo-vertebral material. Consequently, we designed a validated protocol based on anatomical features observed in the literature and the CT scanned ribcages of 10 adult European individuals. After quantifying the shape of these ribcages using 3D geometric morphometrics, we split each vertebra and rib within their corresponding (semi)landmarks. Subsequently, individual bones + (semi)landmarks were imported to LhpFusionBox, commingled and 3D reconstructed. To validate the accuracy of the protocol, we first reconstructed a randomly chosen ribcage three times and then compared these reconstructions to the rest of the sample. Since these reconstructions were closer to their original counterpart than to the others, the remaining sample was reconstructed once. Next, we tested the intra-observer error during reconstructing using the Procrustes distances among the original ribcages and the reconstructions. We observed that first each ribcage reconstruction was clustered to its original counterpart and second there was a learning curve showing an improvement in the reconstruction process over time. Subsequently, we explored general size and shape differences among the original and reconstructed ribcages through a study of centroid size and a permutation test on the Procrustes distances (10,000 permutations), respectively. Specific shape differences between both groups were further examined through a principal component analysis in shape space. None of these analyses found statistical differences between the original and reconstructed ribcages (p > 0.05). Eventually, we extracted the mean shapes of the original ribcages and the reconstructions in order to visualize potential deviations caused by the anatomical considerations of the researcher. These results demonstrate that the protocol is accurate enough to be used when reconstructing a disarticulated human ribcage.

Morphological patterns of the rib cage and lung in the healthy and adolescent idiopathic scoliosis.

The morphology of the rib cage affects both the biomechanics of the upper body's musculoskeletal structure and the respiratory mechanics. This becomes particularly important when evaluating skeletal deformities, as in adolescent idiopathic scoliosis (AIS). The aim of this study was to identify morphological characteristics of the rib cage in relation to the lung in patients with non-deformed and scoliotic spines. Computed tomography data of 40 patients without any visible spinal abnormalities (healthy group) and 21 patients with AIS were obtained retrospectively. All bony structures as well as the right and left lung were reconstructed using image segmentation. Morphological parameters were calculated based on the distances between characteristic morphological landmarks. These parameters included the rib position, length, and area, the rib cage depth and width, and the rib inclination angle on either side, as well as the spinal height and length. Furthermore, we determined the left and right lung volumes, and the area of contact between the rib cage and lung. Differences between healthy and scoliotic spines were statistically analysed using the t-test for unpaired data. The rib cage of the AIS group was significantly deformed in the dorso-ventral and medio-lateral directions. The anatomical proximity of the lung to the ribs was nearly symmetrical in the healthy group. By contrast, within the AIS group, the lung covered a significantly greater area on the left side of the rib cage at large thoracic deformities. Within the levels T1-T6, no significant difference in the rib length, depth to width relationship, or area was observed between the healthy and AIS groups. Inferior to the lung (T7-T12), these parameters exhibited greater variability. The ratio between the width of the rib cage at T6 and the thoracic spinal height (T1-T12) was significantly increased within the thoracic AIS group (1.1 ± 0.08) compared with the healthy group (1.0 ± 0.05). No statistical differences were found between the lung volumes among all the groups. While the rib cage was frequently strongly deformed in the AIS group, the lung and its surrounding ribs appeared to be normally developed. The observed rib hump in AIS appeared to be formed particularly by a more ventral position of the ribs on the concave side. Furthermore, the rib cage width to spinal height ratio suggested that the spinal height of the thoracic AIS-spine is reduced. This indicates that the spine would gain its growth-related height after correcting the spinal deformity. These are the important aspects to consider in the aetiology research and orthopaedic treatment of AIS.

Utility of thoracic cage width in assessing surgical difficulty of minimally invasive esophagectomy in left lateral decubitus position.

BACKGROUND: This study aimed to assess the surgical difficulty of minimally invasive esophagectomy in the left lateral decubitus position for patients with esophageal cancer from the perspective of short-term outcomes, including operation time, blood loss, and morbidity. MATERIALS AND METHODS: The initial 44 consecutive patients with esophageal cancer who underwent minimally invasive esophagectomy were statistically analyzed retrospectively. Thoracic cage area was measured from preoperative computed tomography as a factor affecting the surgical difficulty of minimally invasive esophagectomy, as well as other patient characteristics. Correlations with short-term outcomes including chest operation time, blood loss, and morbidity rate were then examined. RESULTS: In univariate analyses, smaller area of the upper thoracic cage width correlated with prolonged thoracic procedure time (p = 0.0119) and greater blood loss during thoracic procedures (p = 0.0283), but area of the lower thoracic cage showed no correlations. History of respiratory disease was associated with thoracic procedure time (p < 0.0001), but not blood loss. In multivariate analysis, small area of the upper thoracic cage was independently associated with prolonged thoracic procedure time (p = 0.0253). Small upper thoracic cage area was not directly correlated with morbidity rate, but prolonged thoracic procedure time was associated with increased blood loss (p < 0.0001) and morbidity rate (p = 0.0204). Empirical time reduction (p = 0.0065), but not blood loss, was associated with thoracic procedure time. However, area of the upper thoracic cage did not correlate with empirical case number. In multivariate analysis, area of the upper thoracic cage (p = 0.0317) and empirical case number (p = 0.0193) correlated independently with thoracic procedure time. CONCLUSION: A small area of the upper thoracic cage correlated significantly with prolonged thoracic procedure time and increased thoracic blood loss for minimally invasive esophagectomy in the left lateral decubitus position, suggesting the surgical difficulty of minimally invasive esophagectomy in the left lateral decubitus position.

Improved Dynamics of Thoracic Cage and Exercise Capacity after Nuss Repair for Pectus Excavatum.

BACKGROUND: Pectus excavatum (PE) reduces the dynamics of the thoracic cage, with a negative impact on exercise capacity. We aimed to evaluate the effects of Nuss repair for PE on the dynamics of the thoracic cage and exercise capacity in adults. METHODS: This was a prospective observational study of 46 adults (mean age, 26.2 years) who underwent PE correction using the Nuss procedure between September 2016 and August 2017. Cirtometry was used to obtain measures of thoracic cage circumference at two levels (axillary level [AL] and xyphoid level [XL]), at the end points of inspiration and expiration. Circumference measures were obtained before surgery and at 1, 3, and 6 months after surgery. Exercise capacity was also evaluated using the 6-minute walk test (6MWT). The association between the 6MWT data and cirtometry measures was evaluated using Pearson's correlation. RESULTS: The circumference at maximum inspiration increased from baseline to 3 months after surgery (p < 0.01), at both the AL (84.5 ± 4.9 vs. 88.5 ± 5.1 cm) and XL (80.1 ± 4.8 vs. 83.7 ± 5.1 cm). The 6MWT also significantly improved from baseline to 3 months after surgical correction (544.7 ± 64.1 vs. 637.3 ± 59.4 m, p < 0.01), with this improvement being correlated to the increase in thoracic circumference on maximal inspiration at both the AL and XL (0.8424 and 0.7951, respectively). CONCLUSION: Improved dynamics of the thoracic cage were achieved after Nuss repair for PE in adults. This increase in thoracic circumference at maximum inspiration was associated with an improvement in exercise capacity at 3 months after surgery.

Quadrangular Fixation of Pectus Bars to Prevent Displacement in Nuss Procedure.

BACKGROUND: Double pectus bars are sometimes inserted to correct pectus excavatum. Method of double-bar fixation to prevent bar displacement has been rarely reported. We have used quadrangular fixation of the double pectus bars. The objective of this study was to compare results of the quadrangular fixation procedure with those of the classic separate fixation procedure. METHODS: From September 2011 to January 2016, 86 patients underwent Nuss procedure with double-bar insertion. In 44 patients, each bar was fixed separately (group A). In 42 patients, quadrangular fixation of the bars was performed with metal plates (group B). Patient demographics, Haller index (HI), bar displacement index (BDI), and reoperation rate were compared between the two groups. RESULTS: The mean patient age was 17.2 years (range: 3-40 years) in group A and 17.8 years (range: 4-30 years) in group B. There was no significant difference in preoperative or postoperative HIs between the two groups (all p >0.05). Early complication rates were 15.9% in group A and 9.5% in group B (p > 0.05). In group A, three patients underwent surgery to correct bar displacement (6.8% of reoperation rate), whereas there was no corrective surgery in group B. BDIs of the two groups were significantly different (p < 0.01). CONCLUSIONS: When quadrangular fixation was performed with upper and lower pectus bars bilaterally fixed by connecting each bar with plates, bar displacement was prevented more effectively than separate fixation, thus minimizing reoperation.

Rib Cage Measurement Reproducibility Using Biplanar Stereoradiographic 3D Reconstructions in Adolescent Idiopathic Scoliosis.

BACKGROUND: A reproducibility study of preoperative rib cage three-dimensional (3D) measurements was conducted for patients with Adolescent Idiopathic Scoliosis (AIS). No prior reliability study has been performed for preoperative 3D reconstructions of the rib cage by using stereoradiography in patients with preoperative AIS. Our objective was to assess the reliability of rib cage 3D reconstructions using biplanar stereoradiography in patients with AIS before surgery. METHODS: This series includes 21 patients with Lenke 1 or 2 scoliosis (74±20 degrees). All patients underwent low-dose standing biplanar radiographs. Two operators performed reconstructions twice each. Intraoperator repeatability, interoperator reproducibility, and intraclass coefficients (ICC) were calculated and compared between groups. RESULTS: The average rib cage volume was 4.71 L (SD±0.75 L). Two SD was 0.19 L with a coefficient of variation of 4.1%; ICC was 0.968. The thoracic index was 0.6 (SD±0.1). Two SD was 0.03 with a coefficient of variation of 4.7% and a ICC of 0.820. As for the Spinal Penetration Index (6.4%; SD±2.4), 2SD was 0.9% with a coefficient of variation of 14.3% and a ICC of 0.901. The 3D rib hump 2SD (average 27±8 degrees) was 1.4 degrees. The coefficient of variation and ICC were respectively 5.1% and 0.991. CONCLUSIONS: Three-dimensional reconstruction of the rib cage using biplanar stereoradiography is a reliable method to estimate preoperative thoracic parameters in patients with AIS. LEVEL OF EVIDENCE: Level IV-diagnostic study.

Dynamic 3D Reconstruction of Thoracic Cage and Abdomen in Children and Adolescents With Scoliosis: Preliminary Results of Optical Reflective Motion Analysis Assessment.

BACKGROUND: In patients with untreated scoliosis or in those with posterior spinal instrumented fusion (PSF), the movements of neither the thoracic cage (ThC) nor the abdomen (ABD) during quiet and deep breathing have been well defined in the literature. The purpose of this study was to evaluate kinematic variations in the ThC and ABD during quiet and deep breathing by optical reflective motion analysis (ORMA) in children with scoliosis. METHODS: The study included 6 healthy children (group A), 7 subjects with untreated scoliosis over 50 degrees (group B), and 8 patients with scoliosis treated by PSF (group C). After anthropometric measurements (standing height, sitting height, arm span, chest perimeter, body weight, body mass index, T1-T12, and L1-L5 length) were obtained, the movements of subjects during quiet and deep breathing were measured with a 10-camera 3-dimensional ORMA system (82 markers) with the subjects in a standard standing position. RESULTS: No significant differences were observed in sex, age, weight, height, or arm span (P>0.05). Significant differences were observed in the chest perimeter, Cobb angle, and body mass index (P<0.05). ThC and ABD movements during quiet and deep breathing decreased significantly in group B and C when compared with group A (P<0.05). Group B showed decreased expansion of the ThC (-52.4% to -58.3%) and relatively increased motion of the ABD compared with groups A and C (P<0.001). However, ABD expansion remained lower in group B than in groups A and C (-32.8% and -5.7%). PSF does not completely eliminate transverse plane kinematics, although a greater reduction was observed at instrumented than noninstrumented levels (-60.8% vs. -35.1%; P<0.05). CONCLUSIONS: ORMA is a useful tool for assessing alterations in the kinematics of the ThC and ABD caused by severe scoliosis and/or PSF. Compared with normal subjects, patients with severe scoliosis had poorer and less effective kinematics of the ThC and ABD. In contrast, operated subjects had better and more effective kinematics of the ThC and ABD, breathing curves, thoracic expansion, and abdominal movements closer to normal compared with patients with severe, untreated deformity. LEVEL OF EVIDENCE: Level III.

Biplanar stereoradiography predicts pulmonary function tests in adolescent idiopathic scoliosis: a cross-sectional study.

PURPOSE: Various spinal and rib cage parameters measured from complex examinations were found to be correlated with preoperative pulmonary function tests (PFT). The aim was to investigate the relationship between preoperative rib cage parameters and PFT using biplanar stereoradiography in patients with severe adolescent idiopathic scoliosis. METHODS: Fifty-four patients, 45 girls and nine boys, aged 13.8 ± 1.2 years, with Lenke 1 or 2 thoracic scoliosis (> 50°) requiring surgical correction were prospectively included. All patients underwent preoperative PFT and low-dose biplanar X-rays. The following data were collected: forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, residual volume, slow vital capacity (SVC), total lung capacity (TLC), rib cage volume (RCV), maximum rib hump, maximum width, mean thoracic index, spinal penetration index, apical vertebral rotation, main curve Cobb angle (MCCA), T4-T12 kyphosis. The primary outcome was the relationship between rib cage parameters and PFT. The secondary outcome was the relationship between rib cage parameters and spine parameters. Data were analyzed using Spearman's rank test. A multivariable regression analysis was performed to compare PFTs and structural parameters. Significance was set at α = 0.05. RESULTS: The mean MCCA was 68.7° ± 16.7°. RCV was highly correlated with all pulmonary capacities: TLC (r = 0.76, p < 0.0001), SVC (r = 0.78, p < 0.0001) and FVC (r = 0.77, p < 0.0001). RCV had a low correlation with FEV1/FVC (r = - 0.34, p = 0.014). SPI was not correlated with any pulmonary parameters. CONCLUSION: Rib cage volume measured by biplanar stereoradiography may represent a prediction tool for PFTs. LEVEL OF EVIDENCE: Non-randomized cross-sectional study among consecutive patients, Level 2. These slides can be retrieved under Electronic Supplementary Material.

3D spinal and rib cage predictors of brace effectiveness in adolescent idiopathic scoliosis.

BACKGROUND: Scoliotic braces are the standard of curve for management of moderate spinal deformities in pediatric patients. The effectiveness of this treatment method has been shown; however, the spinal and rib cage parameters, in the three anatomical planes, that are associated with bracing outcome in adolescent idiopathic scoliosis (AIS) are not fully identified. METHODS: A total number of 45 right thoracic AIS patients who had received a thoraco-lumbo-scaral brace for the first time were included retrospectively. For each patient, radiographic images at three visits, pre-brace, in-brace, and at least 1 year after the first brace fit were included. Age, sex, Risser sign, and curve type at pre-brace, and thoracic and lumbar frontal and sagittal Cobb angles, thoracic and lumbar apical rotations, sagittal and frontal balances at pre-brace and in-brace were determined. Two sagittal curve types (hypothoracolumbar and normal/hyperthoracolumbar kyphosis), two rib cage types based on the costovertebral joints (drooping and horizontal), and two axial shapes of the spine (S shaped and V shaped) were used to stratify the patients. Feature selection and linear regression with regularization determined the parameters and the interaction terms that predicted the brace effectiveness significantly. RESULTS: Smaller in-brace thoracic Cobb and larger in-brace lordosis predicted brace effectiveness, p < 0.05. Impact of the out of brace lordosis on the brace success increased as the in brace kyphosis angle decreased, p = 0.046. A larger out of brace lordosis in hypothoracolumbar sagittal profile type patients improved the outcomes, p = 0.031. A smaller out of brace thoracic rotation improved the bracing outcomes in patients with horizontal ribs, p = 0.040. CONCLUSION: Both 3D patient specific parameters (lordosis, thoracic rotation, shape of the rib cage, and sagittal profile) and brace design (which allows larger in brace lordosis, better in brace Cobb correction) are important predictors of the brace effectiveness in AIS.

Thoracic cage volume and dimension assessment by optoelectronic molding in normal children and adolescents during growth.

PURPOSE: The thoracic spine, the chondral and osseous ribs, and the sternum together make up the thoracic cage. These elements are strictly correlated, although their growth is not synchronous. The purpose of this study is to provide a comprehensive data set of thoracic dimensions and non-invasive volumetric assessment in a large cohort of males and females from early childhood to young adult age. METHODS: In all, 622 healthy individuals (406 girls, 216 boys) aged 6-18 years were consecutively enrolled between 2006 and 2016. All had to be healthy with no history of spinal deformity, or any lung, cardiovascular, systemic or neuromuscular disease. The optical ORTEN system for trunk surface data acquisition was used to calculate thoracic cage volume (V) and perimeter (Pe), anterior-posterior depth (AP) and transverse diameter (TD), AP/TD ratio, sternal length (St), and T1-T12 distance (Tle) in all patients. RESULTS: The overall average age was 11.1 ± 2.5 years (4-18) for girls and 11.0 ± 3.1 years (4-18) for boys. Average growth parameters were: standing height 146.2 ± 14.6 cm (103-172) for girls and 146.4 ± 20.0 cm (94-192) for boys, sitting height 75.4 ± 8.6 cm (61-91) for girls and 75.5 ± 10.3 cm (60-99) for boys, weight 37.6 ± 10.4 kg (16-65) for girls and 38.3 ± 14.3 kg (13.7-104) for boys, BMI 16.7 ± 3.7 (18.5-26) for girls and 17.0 ± 3.3 (18.7-34.3) for boys. At age 6-8 years: V was 52.5% of its final size in girls and 44.9% in boys; Pe was 80.2% its final length in girls and 76.8% in boys; St reached 68% of its final size in girls and 66.9% in boys; Tle reached 73.3% of its final length in girls and 71.2% in boys. At skeletal maturity, thoracic cage volume in boys was 19.4% greater than in girls (p < 0.05). AP/TD ratio remained < 1 in all age groups and did not differ between genders (p > 0.05). CONCLUSION: Growth of the thoracic cage is shown to be a gradual process that is more linear than previously reported. Only small increases in annual growth rates were observed during the pubertal growth spurt. The most important events characterizing thoracic cage development occurred during the first few years of postnatal growth. The circular cross-section of the very young child's thorax reached adult-like proportions together with its ovoid shape before age 6 years.

Eco-geographic adaptations in the human ribcage throughout a 3D geometric morphometric approach.

OBJECTIVES: According to eco-geographic rules, humans from high latitude areas present larger and wider trunks than their low-latitude areas counterparts. This issue has been traditionally addressed on the pelvis but information on the thorax is largely lacking. We test whether ribcages are larger in individuals inhabiting high latitudes than in those from low latitudes and explored the correlation of rib size with latitude. We also test whether a common morphological pattern is exhibited in the thorax of different cold-adapted populations, contributing to their hypothetical widening of the trunk. MATERIALS AND METHODS: We used 3D geometric morphometrics to quantify rib morphology of three hypothetically cold-adapted populations, viz. Greenland (11 individuals), Alaskan Inuit (8 individuals) and people from Tierra del Fuego (8 individuals), in a comparative framework with European (Spain, Portugal and Austria; 24 individuals) and African populations (South African and sub-Saharan African; 20 individuals). RESULTS: Populations inhabiting high latitudes present longer ribs than individuals inhabiting areas closer to the equator, but a correlation (p < 0.05) between costal size and latitude is only found in ribs 7-11. Regarding shape, the only cold adapted population that was different from the non-cold-adapted populations were the Greenland Inuit, who presented ribs with less curvature and torsion. CONCLUSIONS: Size results from the lower ribcage are consistent with the hypothesis of larger trunks in cold-adapted populations. The fact that only Greenland Inuit present a differential morphological pattern, linked to a widening of their ribcage, could be caused by differences in latitude. However, other factors such as genetic drift or specific cultural adaptations cannot be excluded and should be tested in future studies.

[Giant Cell Tumor of the Rib;Report of a Case].

We report a rare case of giant cell tumor of the rib. A 33-year-old man was admitted to our hospital because of a recently appearing mass and pain in the right chest wall. Chest computed tomography and magnetic resonance imaging revealed a heterogeneous mass of 8-cm in diameter arising from and destroying the right 7th rib. The tumor was resected together with the 6th, 7th, and 8th ribs and the adjacent muscle and diaphragm. The pathological diagnosis was giant cell tumor of the bone. The patient has been free from recurrence or metastasis for 4 years after the operation.

Cardiothoracic Ratio and All-Cause Mortality and Cardiovascular Disease Events in Hemodialysis Patients: The Q-Cohort Study.

BACKGROUND: Cardiothoracic ratio by chest radiography is commonly used to assess volume status. Little is known about the relationships between cardiothoracic ratio and the incidence of clinical outcomes in patients undergoing hemodialysis (HD). STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: 3,436 participants in the Q-Cohort Study 18 years or older who underwent maintenance HD in Japan. PREDICTOR: Cardiothoracic ratio. OUTCOMES & MEASUREMENTS: All-cause mortality and cardiovascular disease (CVD) events. RESULTS: During a 4-year follow-up period, 564 (16.4%) patients died of any cause and 590 (17.2%) developed CVD events. From baseline cardiothoracic ratios, participants were categorized into sex-specific quartiles because cardiothoracic ratio distribution differed by sex. The 4-year event-free survival rate, in terms of all-cause mortality and CVD events, was significantly lower with higher cardiothoracic ratios. Compared to the lowest cardiothoracic ratio (quartile 1), multivariable-adjusted HRs for all-cause mortality were 0.89 (95% CI, 0.66-1.20), 1.41 (1.08-1.86), and 1.52 (1.17-2.00) in patients from quartiles 2, 3, and 4, respectively. Similarly, in comparison to quartile 1, multivariable-adjusted HRs for CVD events were 1.00 (95% CI, 0.77-1.31), 1.18 (0.92-1.53), and 1.37 (1.07-1.76) in patients from quartiles 2, 3, and 4, respectively. Furthermore, the combination of higher cardiothoracic ratio and normohypotension (systolic blood pressure < 140mmHg and diastolic blood pressure < 90mmHg) was associated with higher risk for CVD events. LIMITATIONS: Single measurement of all variables, potentially less-heterogeneous patient population, and limited ascertainment of cardiac parameters and the outcomes. CONCLUSIONS: Higher cardiothoracic ratio is associated with higher risk for both all-cause mortality and CVD events in patients undergoing HD.

Scapulothoracic Joint Dysfunction.

Scapulothoracic derangements are often overlooked and hidden within the clinical fog created by complex back, shoulder, and rib symptoms. This study reviewed 200 magnetic resonance imaging and computed tomography studies dedicated for scapular imaging between January 2010 and May 2016. This article discusses scapulothoracic pathologies and imaging findings.

Estimating pulmonary function after surgery for adolescent idiopathic scoliosis using biplanar radiographs of the chest with 3D reconstruction.

AIMS: This study addressed two questions: first, does surgical correction of an idiopathic scoliosis increase the volume of the rib cage, and second, is it possible to evaluate the change in lung function after corrective surgery for adolescent idiopathic scoliosis (AIS) using biplanar radiographs of the ribcage with 3D reconstruction? METHODS: A total of 45 patients with a thoracic AIS which needed surgical correction and fusion were included in a prospective study. All patients underwent pulmonary function testing (PFT) and low-dose biplanar radiographs both preoperatively and one year after surgery. The following measurements were recorded: forced vital capacity (FVC), slow vital capacity (SVC), and total lung capacity (TLC). Rib cage volume (RCV), maximum rib hump, main thoracic curve Cobb angle (MCCA), medial-lateral and anteroposterior diameter, and T4-T12 kyphosis were calculated from 3D reconstructions of the biplanar radiographs. RESULTS: All spinal and thoracic measurements improved significantly after surgery (p < 0.001). RCV increased from 4.9 l (SD 1) preoperatively to 5.3 l (SD 0.9) (p < 0.001) while TLC increased from 4.1 l (SD 0.9) preoperatively to 4.3 l (SD 0.8) (p < 0.001). RCV was correlated with all functional indexes before and after correction of the deformity. Improvement in RCV was weakly correlated with correction of the mean thoracic Cobb angle (p = 0.006). The difference in TLC was significantly correlated with changes in RCV (p = 0.041). It was possible to predict postoperative TLC from the postoperative RCV. CONCLUSION: 3D rib cage assessment from biplanar radiographs could be a minimally invasive method of estimating pulmonary function before and after spinal fusion in patients with an AIS. The 3D RCV reflects virtual chest capacity and hence pulmonary function in this group of patients. Cite this article: Bone Joint J 2022;104-B(1):112-119.

Three-dimensional reconstruction image by biplanar stereoradiography reflects pulmonary functional states inadolescent idiopathic scoliosis.

This study investigated whether the rib cage parameters estimated based on reconstructed three-dimensional (3D) images with biplanar stereoradiography reflect pulmonary functional states in adolescent idiopathic scoliosis (AIS) patients. A total of 67 Lenke type 1 or 2 AIS patients (59 females and 8 males, mean age 14.4 years) were enrolled. All patients underwent preoperative pulmonary functional tests (PFT) and biplanar stereoradiography. Vital capacity (VC) and forced vital capacity (FVC) pulmonary functional data were collected. Rib-cage parameters (maximum thickness, maximum width, thoracic index (TI), rib hump (RH), rib-cage volume (RCV), spinal penetration index (SPI), endothoracic hump ratio (EHR), vertebra-sternum angle (VSA), rib vertebral angle difference (RVAD), and vertebral lateral decentering (VLD)) were quantified from 3D images. Patients were divided into two groups: restrictive lung disorder (RLD) (%FVC < 80%) and non-RLD (%FVC ≥ 80%). The maximum width and RCV were significantly correlated with VC (p < 0.0001), and FVC (p < 0.0001). RH, EHR, and VSA were negatively correlated with %FVC (p < 0.01). TI, SPI, and RVAD were not correlated with any pulmonary parameters. The maximum widths of RLD patients were significantly shorter than those of the non-RLD patients (218.3 mm vs. 229.7 mm, p < 0.01). The RCV of RLD patients was significantly smaller than that of the non-RLD patients (3.94 L vs. 4.49 L, p < 0.0001). The maximum width and RCV measured by 3D images with biplanar stereoradiography reflected pulmonary functional variables in patients with AIS.

Three-Dimensional Analysis of Preoperative and Postoperative Rib Cage Parameters by Simultaneous Biplanar Radiographic Scanning Technique in Adolescent Idiopathic Scoliosis: Minimum 2-Year Follow-Up.

STUDY DESIGN: Prospective study. OBJECTIVE: This study aimed to investigate the changes in rib cage deformity in adolescent idiopathic scoliosis (AIS) by comparing the preoperative and postoperative three-dimensional (3D) reconstruction images using simultaneous biplanar radiographic scanning technique (EOS) (EOS Imaging, Paris, France). SUMMARY OF BACKGROUND DATA: EOS data are limited for the analyses of preoperative and postoperative rib cage deformity. METHODS: A total of 67 Lenke type 1 or 2 AIS patients who underwent surgery (59 females and 8 males) were enrolled in this study. The mean patient age was 14.4 years (range: 11-17 yr). In all patients, posterior corrective fusion was performed with a rod rotation maneuver based on segmental pedicle fixation. Spinal parameters (scoliosis and kyphosis) and rib cage parameters (max thickness, thoracic index (TI), rib hump (RH), surface spinal penetration index (sSPI), end thoracic hump ratio, vertebra-sternum angle, rib vertebral angle difference at the apex, and vertebral lateral decentering), were measured. 3D images were assessed preoperatively and postoperatively at 2-year follow-up. RESULTS: Both main thoracic (MT) and proximal thoracic scoliosis were significantly corrected (51° to 15°, 30° to 17°, P < 0.0001). The rotation of MT apical vertebrae was also significantly corrected (12° to 5°, P < 0.0001). Thoracic kyphosis (T4-T12) significantly increased (13° to 18°, P < 0.0001). Besides, max thickness, TI, and RH demonstrated significant differences between preoperative and postoperative images (P < 0.01). T8-10 sSPI and end thoracic hump ratio decreased significantly postoperatively (P < 0.05). Although surgery significantly decreased vertebra-sternum angle (P < 0.0001), no significant difference was observed between the preoperative and postoperative rib vertebral angle difference (P = 0.32). Following the surgery, vertebral lateral decentering and rib cage volume were significantly increased (P < 0.0001). CONCLUSIONS: 3D reconstruction of the rib cage using biplanar standing stereoradiography is useful to evaluate preoperative and postoperative rib cage deformity in patients with AIS.Level of Evidence: 2.

Reinforcing the vascular disruption theory of the genesis of Poland's syndrome: a rare association of diaphragmatic eventration in a preterm infant with severe musculoskeletal defects.

A preterm female infant was admitted at birth with respiratory distress. On examination, she had an asymmetric right chest wall and ipsilateral small hand. Air entry was reduced over the right chest. A clinical diagnosis of Poland's syndrome was made based on the hypoplasia of the right pectoral muscles, absent nipple, deformed ribs and symbrachydactyly of the ipsilateral hand. Chest X-ray suggested and ultrasound confirmed eventration of the right hemidiaphragm. 'Subclavian artery supply disruption sequence' (SASDS) theory by Bavnick and Weaver remains the most accepted pathogenic mechanism in Poland's syndrome. This case reinforces SASDS theory associated with the genesis of Poland's syndrome that relates to the pathogenicity of vascular disruption of subclavian artery, characteristics of which are unilateral pectoral defects, symbrachydactyly and eventration of the diaphragm. At 2 months, she underwent diaphragm plication. She is under review by our multidisciplinary surgical team for reconstruction of the chest deformity.