Chest Wall Shape Research Articles

Rib Reduction Technique in Patients with Isolated Chondrocostal Chest Wall Prominence Undergoing Breast Augmentation.

When planning for breast augmentation, it is important to consider not only implant choice, surgical technique and patient desires, but also the chest wall shape and deformities or irregularities, which remain often underestimated. They can be responsible for implant malposition and breast asymmetry after augmentation. Chondrocostal junction prominence is a minor but frequent chest wall deformity. The aim of this study is to report a new technique for sculpturing isolated chondrocostal prominence deformities in patients undergoing breast augmentation. A retrospective study was conducted to review surgical outcomes of a novel technique for costal prominence sculpturing and reshaping in patients undergoing breast augmentation. After reaching the subpectoral space, an inferiorly-based perichondral-periosteal flap is harvested just above the prominence. Once the deformity is corrected, the perichondral flap is repositioned over the sculpted rib. A total of six patients presenting with isolated chondrocostal prominence underwent bilateral breast implant placement and costal reduction using the described technique. Three patients were primary augmentations while the remaining patients were two secondary breast augmentation and one augmentation mastopexy. No complications were reported. No additional pain was referred at the side of rib remodelling in comparison with the contralateral breast. All the patients were satisfied with cosmetic results. The described technique for contouring of isolated chondrocostal deformities is fast, easy reproducible and offers advantages over the standard partial rib reduction technique. It can prevent implant malposition and projection asymmetry, eventually enhancing breast augmentation outcomes. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

New Insights Into Breast and Chest Wall Asymmetry in the Aesthetic Patient

Abstract Background Asymmetry, a prevalent phenomenon throughout the human body, prompts this retrospective study, in which the authors aim at discerning potential patterns in its manifestation. Building upon our previous investigations in which left-sided chest wall and pelvic bone width surpassed their right-sided counterparts, a hypothesis is formulated suggesting the likelihood of the right breast being narrower and longer compared with the left. Objectives Our objective in this study is to investigate the correlation between the left-sidedness phenomenon in the chest wall and breast shape and appearance, with the aim of understanding its potential impact on outcomes in breast aesthetic surgery. Methods A random selection of pictures from 600 female patients undergoing various aesthetic breast procedures formed the basis of this study. Exclusion criteria involved the elimination of 254 pictures with nonstandard photography. Horizontal and vertical parameters of breasts and chest walls were measured, and the results on both sides were systematically compared to validate our hypothesis. Results On the left side, the chest wall, the distance between the nipple and the midline, and that of the nipple and the anterior axillary line were significantly wider. Vertical measurements, including the sternal notch to the nipple, the clavicle to the nipple, and the clavicle to inferior breast distance, although longer, did not exhibit statistical significance. Conclusions Approximately 77% of patients displayed wider breasts and chest walls on the left side. However, this observed asymmetry did not yield a statistically significant impact on the length of the breasts. Level of Evidence: 3 (Diagnostic)

Modified Haller index is inversely correlated with true positive exercise stress echocardiographic results.

The influence of chest wall shape on exercise stress echocardiography (ESE) results has been poorly investigated. We aimed at evaluating the main predictors of true positive (TP)-ESE in a population of subjects with suspected coronary artery disease (CAD), categorized according to chest wall conformation, assessed by modified Haller index (MHI, chest transverse diameter over the distance between sternum and spine). All consecutive patients with suspected CAD referred to our EchoLab for performing ESE between September 2011 and October 2021 were retrospectively enrolled. Preliminary assessment of both pretest probability (PTP) and MHI was performed. All patients with positive ESE underwent coronary angiography. Obstructive CAD was diagnosed by ≥70% stenosis in any epicardial coronary artery. Outcome was TP ESE result. One thousand two hundred and seventy-five consecutive patients (64.9 ± 13.0 years) entered the study. Subjects with concave-shaped chest wall (MHI > 2.5) (10.7%) and those with normal chest shape (MHI ≤ 2.5) (89.3%) were separately analyzed. PTP was similar in both groups (21.8 ± 13.2 vs. 23.5 ± 13.3%, P = 0.15). One hundred and seventy patients were diagnosed with positive ESE: 129 (75.9%) had obstructive CAD (TP), whereas the remaining 41 (24.1%) had no CAD. Only 2.3% of TP ESE was detected in subjects with MHI >2.5. PTP [odds ratio (OR) 1.03, 95% confidence interval (CI) 1.01-1.04], dyslipidemia (OR 4.37, 95% CI 2.81-6.80), dyssynergy in the left anterior descending territory (OR 8.21, 95% CI 5.07-13.3) were linearly correlated with TP ESE, whereas MHI >2.5 (OR 0.25, 95% CI 0.14-0.67) was inversely associated with outcome. Subjects with MHI >2.5 have low prevalence of TP ESE, regardless of PTP. Preliminary MHI assessment may reduce overestimation of PTP of CAD.

Surgical approach to treatment of asymmetric pectus excavatum in children

Objective. To improve the outcomes in patients with asymmetric pectus excavatum (APE) by developing and implementing our own differentiated modified Nuss procedure to correct different variants of this deformity; to analyse the treatment outcomes. Materials and methods. An original modified Nuss procedure to correct the following pectus excavatum (PE) types is described: asymmetric eccentric focal (ІІА1 according to Park) type; asymmetric eccentric broad-flat (Park ІІА2) type; asymmetric eccentric long canal (the Grand Canyon type or Park IIA3) type; asymmetric unbalanced (Park IIB) type; asymmetric combined (Park IIC) type. The essence of the proposed technique is that at the beginning of the operation, a gradual elevation of the anterior chest wall is carried out to a maximally approximated physiological position using two or more traction ligatures applied to the sternum and ribs. In the future, a horizontal position of the fixation bar is used for asymmetric eccentric focal, asymmetric eccentric broad-flat, and asymmetric eccentric long canal types; and an oblique position with a more dorsal location of the bar end on the less depressed side is used for asymmetric unbalanced and asymmetric combined types. In both bar position variants, the rigid subperiosteal fixation of the bar stabilizers to two ribs bilaterally is used. The results of treatment according to this modification were analysed in 24 patients with different variants of asymmetric PE. Results. The proposed differentiated approaches to performing the Nuss procedure made it possible to obtain excellent and good cosmetic and functional results. There were three postoperative complications: one case of delayed pneumothorax and two cases of asymmetric manubriocostal pectus carinatum: one case after treatment of an asymmetric unbalanced PE (Park IIB) type and one - after correction of an asymmetric combined (Park IIC) type. Both patients with pectus carinatum underwent non-surgical treatment using an individually tailored dynamic compression brace system with excellent cosmetic and functional outcomes. Conclusions. The several-point traction of the anterior chest wall allows to shape its physiological form in most cases; the rigid bar fixation according to the proposed schemes ensures the retention of the chest wall shape. In the vast majority of cases, the placement of one corrective bar is sufficient. For the asymmetric combined (Park IIC) type correction, the implantation of two corrective bars or the “sandwich technique” is indicated if the defect is significant. In case of postoperative pectus carinatum, successful non-surgical treatment using an individually tailored dynamic compression brace system is possible. The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Keywords: Nuss procedure, asymmetric pectus excavatum, sternum elevation.

Impact of Chest Wall Conformation on the Outcome of Primary Mitral Regurgitation due to Mitral Valve Prolapse.

Background:The possible influence of chest wall conformation on cardiovascular (CV) outcome of patients with mitral regurgitation (MR) due to mitral valve prolapse (MVP) has never been previously investigated.Methods:This retrospective study included all consecutive symptomatic patients with MVP and moderate MR who underwent exercise stress echocardiography at our institution between February 2014 and February 2021. Modified Haller Index (MHI; chest transverse diameter over the distance between sternum and spine) was noninvasively assessed. During the follow-up, we evaluated the occurrence of any of the following: (1) CV hospitalization, (2) mitral valve (MV) surgery, and (3) cardiac death or sudden death.Results:Four hundred and twenty-four consecutive patients (66.8 ± 11.5 years, 48.3% men) were retrospectively analyzed. Overall, MVP patients had concave-shaped chest wall (MHI = 2.55 ± 0.34) and were found with small cardiac chamber dimensions. During a mean follow-up time of 3.2 ± 1.7 years, no patients died, 55 patients were hospitalized due to CV events, and 20 patients underwent MV surgery. On multivariate Cox analysis, age (heart rate [HR] 1.05, 95% confidence interval [CI] 1.03–1.06), diabetes mellitus (HR 3.26, 95% CI 2.04–5.20), peak exercise-E/e' ratio (HR 1.07, 95%CI 1.05–1.09), and peak exercise-effective regurgitant orifice area (HR 2.53, 95% CI 1.83–3.51) were directly associated to outcome, whereas MHI (HR 0.15, 95%CI 0.07-0.33) and beta-blocker therapy (HR 0.26, 95% CI 0.19–0.36) showed strong inverse correlation. An MHI ≥2.7 showed 80% sensitivity and 100% specificity for predicting event-free survival (area under the curve = 0.98).Conclusions:Symptomatic patients with moderate MR due to MVP and MHI ≥2.7 have an excellent prognosis over a medium-term follow-up. Noninvasive chest wall shape assessment should be encouraged in clinical practice.

Tips and Tricks in Gender-Affirming Mastectomy.

Gender-affirming mastectomy has become a highly sought-after procedure for the treatment of gender dysphoria and has been shown to improve quality of life in transgender and gender-nonbinary individuals. Aesthetic outcomes after double-incision mastectomy can be influenced by several factors; however, certain operative variables can be controlled to obtain aesthetic and reproducible results. Chest wall contour is arguably the most critical component of these procedures and requires highlighting the definition of the pectoralis muscle. Planning incisions within the inferior and lateral borders of the pectoralis major rather than the inframammary fold, and ensuring removal of all breast tissue in the lateral and medial chest and the axillary tail, will help obtain an aesthetically pleasing chest wall shape while concealing scars. Finally, attention to nipple resizing and repositioning inferiorly and laterally relative to the borders of the pectoralis muscle are critical to an aesthetic outcome. The authors have found that appropriate preoperative planning to control these three factors-(1) contour, (2) nipple position, and (3) scars-and critical analysis and adjustment of on-table results will help achieve the goals of creating an aesthetic and gender-congruent chest.

Prevalence of pectus excavatum in an adult population-based cohort estimated from radiographic indices of chest wall shape.

Pectus excavatum is the most common chest wall skeletal deformity. Although commonly evaluated in adolescence, its prevalence in adults is unknown. Radiographic indices of chest wall shape were analyzed for participants of the first (n = 2687) and second (n = 1780) phases of the population-based Dallas Heart Study and compared to clinical cases of pectus (n = 297). Thoracic computed tomography imaging studies were examined to calculate the Haller index, a measure of thoracic axial shape, and the Correction index, which quantitates the posterior displacement of the sternum relative to the ribs. At the level of the superior xiphoid, 0.5%, 5% and 0.4% of adult Dallas Heart Study subjects have evidence of pectus excavatum using thresholds of Haller index >3.25, Correction index >10%, or both, respectively. Radiographic measures of pectus are more common in females than males and there is a greater prevalence of pectus in women than men. In the general population, the Haller and Correction indices are associated with height and weight, independent of age, gender, and ethnicity. Repeat imaging of a subset of subjects (n = 992) demonstrated decreases in the mean Haller and Correction indices over seven years, suggesting change to a more circular axial thorax, with less sternal depression, over time. To our knowledge, this is the first study estimating the prevalence of pectus in an unselected adult population. Despite the higher reported prevalence of pectus cases in adolescent boys, this study demonstrates a higher prevalence of radiographic indices of pectus in adult females.

Adaptation of lung, chest wall, and respiratory muscles during pregnancy: preparing for birth.

A plethora of physiological and biochemical changes occur during normal pregnancy. The changes in the respiratory system have not been as well elucidated, in part because radioimaging is usually avoided during pregnancy. We aimed to use several noninvasive methods to characterize the adaptation of the respiratory system during the full course of pregnancy in preparation for childbirth. Eighteen otherwise healthy women (32.3 ± 2.8 yr) were recruited during early pregnancy. Spirometry, optoelectronic plethysmography, and ultrasonography were used to study changes in chest wall geometry, breathing pattern, lung and thoraco-abdominal volume variations, and diaphragmatic thickness in the first, second, and third trimesters. A group of nonpregnant women were used as control subjects. During the course of pregnancy, we observed a reorganization of rib cage geometry, in shape but not in volume. Despite the growing uterus, there was no lung restriction (forced vital capacity: 101 ± 15% predicted), but we did observe reduced rib cage expansion. Breathing frequency and diaphragmatic contribution to tidal volume and inspiratory capacity increased. Diaphragm thickness was maintained (1st trimester: 2.7 ± 0.8 mm, 3rd trimester: 2.5 ± 0.9 mm; P = 0.187), possibly indicating a conditioning effect to compensate for the effects of the growing uterus. We conclude that pregnancy preserved lung volumes, abdominal muscles, and the diaphragm at the expense of rib cage muscles.NEW & NOTEWORTHY Noninvasive analysis of the kinematics of the chest wall and the diaphragm during resting conditions in pregnant women revealed significant changes in the pattern of thoracoabdominal breathing across the trimesters. That is, concomitant with the progressive changes of chest wall shape, the diaphragm increased its contribution to both spontaneous and maximal breathing, maintaining its thickness despite its lengthening due to the growing uterus. These results suggest that during pregnancy the diaphragm is conditioned to optimize its active role provided during parturition.

Winged Ribs: An Underestimated Problem That May Compromise Breast Augmentation Outcomes.

Chest wall shape is an important aspect to consider when planning a breast augmentation. Minor chest wall deformities are usually underestimated by the patient and surgeon and may compromise postoperative outcomes. Lower costal cartilage dysmorphia or winged rib is one of these minor underestimated chest wall deformities characterized by a visible and palpable cartilaginous prominence under the inframammary fold and causes discomfort in patients decreasing the satisfaction with the breast augmentation surgery. For these patients, the author utilized an innovative surgical technique that allows resection of the protruding cartilages and placement of breast implants through the same surgical incision. Six patients with winged ribs underwent breast augmentation and costal cartilage resection via this method and there were no intraoperative or early postoperative complications, and all patients were satisfied with the aesthetical result after 6months of follow-up. The presented surgical technique has a short learning curve with excellent postoperative results. Cases are presented to demonstrate the improved postoperative chest wall contour combined with breast augmentation outcome.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

PHOTOGRAMMETRY: A PROPOSAL OF OBJECTIVE ASSESSMENT OF CHEST WALL IN ADOLESCENT IDIOPATHIC SCOLIOSIS.

ABSTRACTObjective: To evaluate the chest wall shape in patients with adolescent idiopathic scoliosis (AIS) in comparison to healthy subjects and the association between the chest wall shape with the spine deformity and lung function in patients with AIS.Methods: This cross-sectional study enrolled 30 AIS patients and 20 healthy subjects aged 11-18 years old. The Cobb angle evaluation was performed in AIS patients. The chest wall shape was assessed by the photogrammetry method, using the Postural Assessment Software (PAS). We created thoracic markers shaped as angles (A) and distances (D), as follows: A2 (right acromion/xiphoid/left acromion), A4L (angle formed between the outer point of the smallest waist circumference and its upper and lower edges on the left side), A7 (angle formed by the intersection of the tangent segments of the upper and lower scapulae angles), D1R/D1L [distance between the xiphoid process and the last false rib on the right (R) and left (L) sides], and D3 (distance between xiphoid process and anterior superior iliac spine).Results: The thoracic markers A2 and A7 were significantly higher, while the A4L and D1R/D1L were significantly reduced in the AIS group compared to the control. Moderate correlations were found between: A2 and the main and proximal thoracic Cobb angles (r=0.50, r=0.47, respectively); D1R/D1L and the main thoracic Cobb angle (r=- 0.40); and the forced expiratory volume in the first second (FEV1) and D3R (r=0.47).Conclusions: The photogrammetry method was able to detect chest wall changes in AIS patients, besides presenting correlation between Cobb angles and lung function.

Computer-Aided Design and Manufacturing Technology for Identification of Optimal Nuss Procedure and Fabrication of Patient-Specific Nuss Bar for Minimally Invasive Surgery of Pectus Excavatum

The Nuss procedure is one of the most widely used operation techniques for pectus excavatum (PE) patients. It attains the normal shape of the chest wall by lifting the patient’s chest wall with the Nuss bar. However, the Nuss bar is for the most part bent by a hand bender according to the patient’s chest wall, and this procedure causes various problems such as the failure of the operation and a decreased satisfaction of the surgeon and patient about the operation. To solve this problem, we proposed a method for deriving the optimal operation result by designing patient-specific Nuss bars through computer-aided design (CAD) and computer-aided manufacturing (CAM), and by performing auto bending based on the design. In other words, a three-dimensional chest wall model was generated using the computed tomography (CT) image of a pectus excavatum patient, and an operation scenario was selected considering the Nuss bar insertion point and the post-operative chest wall shape. Then, a design drawing of the Nuss bar that could produce the optimal operation result was derived from the operation scenario. Furthermore, after a computerized numerical control (CNC) bending machine for the Nuss bar bending was constructed, the Nuss bar prototype was manufactured based on the derived design drawing of the Nuss bar. The Nuss bar designed and manufactured with the proposed method has been found to improve the Haller index (HI) of the pectus excavatum patient by approximately 37% (3.14 before to 1.98 after operation). Moreover, the machining error in the manufacturing was within ±5% compared to the design drawing. The method proposed and verified in this study is expected to reduce the failure rate of the Nuss procedure and significantly improve the satisfaction of the surgeon and patient about the operation.

Changes in training posture induce changes in the chest wall movement and respiratory muscle activation during respiratory muscle training.

Postural changes induce changes in chest wall kinematics and eventually pulmonary function, and affect chest wall shape and chest motion. This study aimed to examine the effects of postural change on changes in the chest wall during respiratory muscle training. Using a repeated measures design, this study followed 13 healthy adults (13 men; mean age, 23.73 years). All participants performed four postures (neutral, full trunk rotation, half-range trunk rotation, and lateral ribcage shift postures) during respiratory muscle training. The chest wall movement during the four postures was measured using a three-dimensional motion-analysis system during respiratory muscle training. Surface electromyography data were collected from the diaphragm and sternocleidomastoid muscles, and the asymmetric ratio of muscle activation was calculated based on the collected data. The chest wall movements of the upper costal and middle costal region were greater in the neutral posture than in the full rotation, half rotation, and lateral ribcage shift postures (P<0.05). The respiratory muscle activation on diaphragm of left was greater in the full rotation posture than in the neutral posture, half rotation, and lateral ribcage shift postures (P<0.05). The asymmetric ratio of muscle activation was greater in the full rotation posture than in the neutral posture, half rotation, and lateral ribcage shift postures (P<0.05). This study verified that postural change during respiratory muscle training may affect chest wall movement and muscle activation. Thus, this study recommends respiratory muscle training to be performed in neutral posture.

Both Bilateral Breast Volume Discrepancy and Asymmetric Anterior Chest Wall Shape Contribute to the Unsightly Breast Contour in Female Right Thoracic Idiopathic Scoliosis.

A retrospective radiographic study. To evaluate the asymmetry of breast volume (BV) and shape in female adolescent idiopathic scoliosis (AIS) patients and to define their relationship with deformed components of the anterior chest wall and curved spine. The higher incidence of asymmetric breast development in AIS was described by prior studies. However, the interplay between scoliosis curve magnitude and severity of breast asymmetry (BA) are unknown. A total of 73 surgically treated female right thoracic AIS patients classified as Lenke type I were enrolled in this study, with the average Cobb angle being 52.08±11.68 degrees. The Image J software was utilized to calculate BV. Both concave and convex radiographic parameters of breast shape were measured including the extraversion angle (EA), the coverage angle (CA), the axial breast height, the vertical breast height (VBH), and the nipple-to-sternum distance. The inclination angles of the concave and convex anterior chest wall were also assessed. BA was calculated according to the formula as follows: BA=(concave-convex)×BV/[(concave+convex)×BV]/2. The measurements of spinal deformity parameters included the Cobb angle, the RAsag angle, and the RAml angle. Paired t test was performed to analyze the asymmetry of breast shape, and Pearson correlation analysis was utilized to define the correlation between the breast shape, spinal deformity, and the inclination of anterior chest wall. The concave BV, EA, axial breast height, and vertical breast height were significantly larger than those of the convex side (P<0.05), whereas the concave CA and the inclination angle of the anterior chest wall were significantly smaller than those of the convex side (P<0.05). No difference was detected between the concave and the convex nipple-to-sternum distance (P>0.05). The averaged BA was 11.4%, with the ratio of asymmetry beyond 10% being 52.1%. No statistically significant relationships between BA and Cobb angle, RAsag angle, RAml angle were detected (P>0.05). The inclination angle of the anterior chest wall demonstrated significant correlation with EA (P<0.001) and CA (P<0.001), respectively. The incidence of BA in AIS is notable, with the concave breast being larger, more extroversive, and more concentrated than the convex breast. The discrepancy between concave and convex anterior chest wall inclination bound to scoliosis could have a major influence on breast orientation and profile, suggesting a synergistic role of anterior chest wall deformity and bilateral BV discrepancy in the formation of BA.

Thoracic wall reconstruction with bioabsorbable plates in pediatric malignant thoracic wall tumors

AimChildhood malignant chest wall tumors may require extensive surgical resection and reconstruction with musculoskeletal flaps or non-resorbable prosthetic materials. Implant-related complications and scoliosis often occur. This study analyzes the outcomes of chest wall reconstruction using resorbable plates as an alternative approach. MethodsRetrospective review (2007–2015) of patients who underwent resection of malignant primary chest wall tumors in 2 tertiary pediatric centers. Reconstruction was performed using copolymer (l-lactic and glycolic acid) plates, fixed to the ribs and surrounding structures with copolymer screws and/or polyglactin sutures. ResultsEight patients aged 10.6+2.6years were treated. There were no operative complications, and implant removal was not required in any case. Six patients received postoperative radiotherapy. Over follow-up (39.6months, range 9.4–78), chest wall shape was maintained in all, and there were no radiological artifacts. Three patients developed scoliosis (Cobb 17°–33°), but treatment was needed only in one, who had undergone hemivertebrectomy. There were no cases of local tumor relapse. One patient died because of metastatic spread. ConclusionsImplantation of bioabsorbable l-lactic and glycolic acid copolymer plates with a relatively simple technique provided a rigid, stable reconstruction with only mild mid-/long-term complications. Resorbable plates may be a good alternative for pediatric chest wall reconstruction.Level of evidence: IV.

A biomechanical hypothesis for the pathophysiology of apical lung disease

ObjectiveA hypothesis is presented suggesting that the pathogenesis of apical lung disease is due to progression of subclinical congenital apical bullae in people with low Body Mass Index (BMI), a combination present in 15% of the population, due to high pleural stress levels present in the antero-posteriorly flattened chests of these individuals. DesignThe hypothesis was tested for validity in two apical lung pathologies with widespread epidemiological literature, namely tuberculosis (TB) and primary spontaneous pneumothorax (PSP), assessing whether the hypothesis could identify high-risk populations, explain exceptional cases like apical lower lobe disease and confirm predictions. ResultsThe biomechanical hypothesis can explain the high-risk factors of apical location, age, gender and low-BMI build, as well as the occurrence of disease in the apex of the lower lobe, in both TB and PSP patients. A predicted common pathogenesis for apical lung disease was confirmed by the higher-than-expected incidence of concomitant TB and PSP. ConclusionPleural stress levels depend on chest wall shape, but are highest in the apex of young males with low BMI, leading to growth of congenital bullae that can eventually limit clearance inhaled material, superinfect or burst. This hypothesis suggests that low-dose computerized tomography may be used to screen for TB eradication. This paper is the first to propose a biomechanical mechanism for all apical lung disease pathophysiology.

PO-0881: Patient selection for DIBH technique for left sided breast cancers: Impact of chest wall shape

PO-0881: Patient selection for DIBH technique for left sided breast cancers: Impact of chest wall shape

Mechanism of sternotomy dehiscence.

Biomechanical modelling of the forces acting on a median sternotomy can explain the mechanism of sternotomy dehiscence, leading to improved closure techniques. Chest wall forces on 40 kPa coughing were measured using a novel finite element analysis (FEA) ellipsoid chest model, based on average measurements of eight adult male thoracic computerized tomography (CT) scans, with Pearson's correlation coefficient used to assess the anatomical accuracy. Another FEA model was constructed representing the barrel chest of chronic obstructive pulmonary disease (COPD) patients. Six, seven and eight trans-sternal and figure-of-eight closures were tested against both FEA models. Comparison between chest wall measurements from CT data and the normal ellipsoid FEA model showed an accurate fit (P < 0.001, correlation coefficients: coronal r = 0.998, sagittal r = 0.991). Coughing caused rotational moments of 92 Nm, pivoting at the suprasternal notch for the normal FEA model, rising to 118 Nm in the COPD model (t-test, P < 0.001). The threshold for dehiscence was 84 Nm with a six-sternal-wire closure, 107 Nm with seven wires, 127 Nm with eight wires and 71 Nm for three figure-of-eights. The normal rib cage closely fits the ellipsoid FEA model. Lateral chest wall forces were significantly higher in the barrel-shaped chest. Rotational moments generated by forces acting on a six-sternal-wire closure at the suprasternal notch were sufficient to cause lateral distraction pivoting at the top of the manubrium. The six-sternal-wire closure may be successfully enhanced by the addition of one or two extra wires at the lower end of the sternotomy, depending on chest wall shape.

Is there a biomechanical cause for spontaneous pneumothorax?

Primary spontaneous pneumothorax has long been explained as being without apparent cause. This paper deals with the effect of chest wall shape and explains how this may lead to the pathogenesis of primary spontaneous pneumothorax. Rib cage measurements were taken from chest radiographs in 12 male pneumothorax patients and 12 age-matched controls. Another group of 15 consecutive male thoracic computerised tomography (CT) were investigated using paramedian coronal and sagittal CT reconstructions to assess apical lung shape. A finite element analysis (FEA) model of a lung apex was constructed, including indentations for the first rib guided by CT scan data, to assess pleural stress. This model was tested using different anteroposterior diameter ratios, producing a range of thoracic indexes. The pneumothorax patients had a taller chest (P = 0.03), wider transversely (P = 0.009) and flatter (P = 0.03) when compared with controls, resulting in a low thoracic index. Prominent rib indentations were found anteriorly and posteriorly on the lung surface, especially on the first rib on CT. FEA of the lung revealed significantly higher stress (×5-×10) in the apex than in the rest of the lung. This was accentuated (×4) in low thoracic index chests, resulting in 20-fold higher stress levels in their apex. The FEA model demonstrates a 20-fold increase in pleural stress in the apex of chests with low thoracic index typical of spontaneous pneumothorax patients. Mild changes in thoracic index, as occurring in females or with aging, reduce pleural stress. Spontaneous pneumothorax occurring in young male adults may have a biomechanical cause.

Role of Anatomical Implant in Augmentation of Glandular Ptotic Breast

Breast augmentation of ptotic micromastia is relatively difficult procedure than simple augmentation. Surgeon must make into account many variables, ptosis degree, chest wall size, shape, asymmetry, nipple and inframammary fold level, soft tissue characteristic etc. One-stage mastopexy augmentation procedure has higher patient acceptance because this limits the number of sick days and the need for hospital care, and it is also less expensive. Because of two procedures that has opposite effect to soft tissue be done in the same time, there can be high incidence of unfavorable outcomes and complications. Some well known doctors recommend that 2-step procedure of mastopexy folllowed by augmentation can be much better option. It can make more predictable result and it is also safe in soft tissue problem and vascularity. In one stage augmentation mastopexy, high and extrahigh projection implants have often been promoted for augmenting glandular ptotic breast, emphasizing the role of implant projection to the sagging parenchyma and skin of lower pole of breast anteriorly to "lift" the breast and "correct" the ptosis. High and extra high profile implants may contribute projection, but they are not the best choice for correction of glandular ptosis. It has several negatives, additional parenchymal atrophy, lower pole skin stretch and thinning and visible and palpable rippling. All of these tissue consequences are irreversible and uncorrectable. Optimal implant design for augmentation of glandular ptotic breast is full height, moderate profile, shaped, textured, form stable implant. Keywords: Breast implants, Silicone gels, Anatomical models, Mammoplasty

Peri‐diaphragmatic lung volume assessed by computed tomography correlates with quality of life in patients with chronic obstructive pulmonary disease

Health-related quality of life (HRQoL) is important in the management of chronic obstructive pulmonary disease (COPD). In patients with emphysema, lung hyperinflation identified radiologically as shortening and flattening of the diaphragm is associated with impaired HRQoL. It remains unclear whether shortening of the diaphragm and/or alteration in chest wall shape are associated with reduced pulmonary function and HRQoL. Pulmonary function testing and chest computed tomography (CT) were performed, and the St. George's Respiratory Questionnaire (SGRQ) was administered to 123 patients with COPD. Using CT images, the ratio of volume of lung region adjacent to the diaphragm dome to total lung volume (DLV%) was evaluated as a novel CT index, and conventional indices, including percent low attenuation volume (LAV%), wall area percent (WA%), total lung volume and diaphragm length (Ldi) were calculated. DLV% was significantly correlated with Ldi. DLV% and Ldi were inversely correlated with lung hyperinflation, assessed as the ratio of residual volume to total lung capacity, independent of LAV% and WA%. Unlike Ldi, DLV% was inversely associated with all components and total scores for the SGRQ, independent of the severity of emphysema and airflow limitation. Reduced lung volume around the diaphragm correlated with lung hyperinflation and HRQoL, independent of emphysema severity. This needs to be verified in additional studies.