Complications due to ultrasound transthoracic cutting biopsy of peripheral pulmonary lesions and lesions in the chest wall and mediastinum.

INTRODUCTION: Evaluation of patients with peripheral lung lesions and lesions of the chest wall and mediastinum is challenging. The nature of the lesion identified by imaging studies can be determined by histological evaluation of biopsies. An important place in this direction is the ever-increasing popularity among thoracic surgeons of the transthoracic biopsy with a cutting needle under ultrasound control (US-TTCNB).

A preliminary study on the normal values of the thoracic Haller index in children.

OBJECTIVES: The Haller index (HI) is widely utilized as a quantitative indicator to assess the extent of the pectus excavatum (PE) deformity, which is the most common chest wall abnormality in children. Both preoperative correction planning and postoperative follow-up need to be based on the standard of normal thoracic growth and development. However, there is currently no established reference range for the HI in children. Consequently, the goal of this study was to conduct a preliminary investigation of normal HI values among children to understand thoracic developmental characteristics. METHODS: Chest computed tomography images obtained from January 2012 to March 2022 were randomly selected from the imaging system of the Children's Hospital of Chongqing Medical University. We divided the images of children into a total of 19 groups: aged 0-3 months (1 group), 4-12 months (1 group) and 1 year to 17 years (17 groups), with 50 males and 50 females, totaling 100 children in each group. HI was measured in the plane where the lowest point of the anterior thoracic wall was located and statistically analysed using SPSS 26.0 software. RESULTS: A total of 1900 patients were included in the study. Our results showed that HI, transverse diameter and anterior-posterior diameter were positively correlated with age (P < 0.05). Using age as the independent variable and HI as the dependent variable, the best-fit regression equations were HI-male = 2.047 * Age0.054(R2 = 0.276, P<0.0001) and HI-female = 2.045 * Age0.067(R2 = 0.398, P<0.0001). Males had significantly larger thoracic diameters than females, and there was little difference in the HI between the 2 sexes. CONCLUSIONS: The HI rapidly increases during the neonatal period, slowly increases during infancy and stops increasing during puberty, with no significant differences between the sexes.

A 25-Year-Old Man with a History of Substance Abuse Presenting with Pneumomediastinum Due to Methamphetamine Vapor Inhalation.

BACKGROUND There has been an increase in the use of inhalation methods to abuse drugs, including freebasing crack cocaine (alkaloid) and inhaling methamphetamine vapor. This report is of a 25-year-old man with a history of substance abuse presenting with pneumomediastinum due to methamphetamine vapor inhalation. Acute pneumomediastinum is an extremely rare complication of methamphetamine use. CASE REPORT A 25-year-old man was treated for polysubstance abuse following 9 days of methamphetamine abuse. EKG did not show any ST &T change. D-dimer was normal, at 0.4 mg/L, so we did not do further work-up for pulmonary embolism. His chest pain worsened in the Emergency Department (ED), and a physical exam demonstrated crepitation of the posterior neck, trapezius, and right scapula. A portable chest X-ray revealed subcutaneous air over the right scapular region, in addition to pneumomediastinum. The urine drug screen test was positive for methamphetamine. A chest CT was ordered, which showed a moderate-volume pneumomediastinum with soft-tissue air tracking into the lower neck and along the right chest wall. The patient underwent an esophagogram, which showed no air leak, and Boerhaave's syndrome was ruled out. His symptoms improved and he did not require any surgical intervention. CONCLUSIONS Considering the higher rates of illicit substance use, especially methamphetamine, it is important to pay attention to the associated pathologies and to keep spontaneous pneumomediastinum on the list of differentials for patients using methamphetamine, particularly those who inhale it, which can cause pneumomediastinum, even without Boerhaave's syndrome.

Breast Pain Differential: Mondor's Disease of the Breast.

Breast pain is a common concern among women in primary care clinics. A rare cause of breast pain is Mondor's disease (MD), which can present as an acute, painful, erythematous, cord-like induration on the breast or anterior chest wall. The disorder is caused by sclerosing superficial thrombophlebitis of the anterolateral thoracoabdominal wall veins. There does not appear to be a racial or ethnic propensity for this condition; however, it is important to understand that it may be more difficult to see in darker skin types (Fitzpatrick skin types IV-VI) and requires close attention on physical exam. The cause of MD is poorly understood but may be related to direct trauma, strenuous exercise, or hormone changes. We review a case of a 54-year-old woman who presented with an anterior chest wall palpable cord, better visualized with adequate lighting and skin traction, ultimately diagnosed as MD based on clinical findings and imaging studies. Mondor's disease often resolves spontaneously with supportive care, as in this patient's case; however, clinicians should be aware of this rare cause of breast pain and its association with hypercoagulable state, vasculitis, and breast cancer.

Chest Wall Motion Model of Cardiac Activity for Radar-Based Vital-Sign-Detection System.

An increasing number of studies on non-contact vital sign detection using radar are now beginning to turn to data-driven neural network approaches rather than traditional signal-processing methods. However, there are few radar datasets available for deep learning due to the difficulty of acquiring and labeling the data, which require specialized equipment and physician collaboration. This paper presents a new model of heartbeat-induced chest wall motion (CWM) with the goal of generating a large amount of simulation data to support deep learning methods. An in-depth analysis of published CWM data collected by the VICON Infrared (IR) motion capture system and continuous wave (CW) radar system during respiratory hold was used to summarize the motion characteristics of each stage within a cardiac cycle. In combination with the physiological properties of the heartbeat, appropriate mathematical functions were selected to describe these movement properties. The model produced simulation data that closely matched the measured data as evaluated by dynamic time warping (DTW) and the root-mean-squared error (RMSE). By adjusting the model parameters, the heartbeat signals of different individuals were simulated. This will accelerate the application of data-driven deep learning methods in radar-based non-contact vital sign detection research and further advance the field.

Reconstruction method for massive lateral chest wall sarcoma using titanium plates and mesh: a case report.

BACKGROUND: Very large chest wall resections can lead to acute thoracic insufficiency syndrome due to the interdependence of lung expansion and thoracic volume. Chest wall tumor surgeries often encounter complications, with the size of the chest wall defect being a significant predictor. Several methods for large chest wall reconstruction have been described, aiming to provide stability, prevent flail chest, and ensure airtight closure. However, no single method fulfills all requirements. Composite chest wall reconstruction using titanium plates and Gore-Tex patches has shown the potential to minimize physiologic abnormalities caused by extensive defects. CASE PRESENTATION: A 42-year-old man with myxofibrosarcoma underwent multiple surgeries, chemotherapies, and radiation therapies due to repeated local recurrences. After right arm amputation and resection of the right third to fifth ribs, a local recurrence was detected. A 30 × 40 cm chest wall defect was resected en bloc, and a titanium plate was used for three-dimensional formability, preventing flail chest and volume loss. The Gore-Tex patch was then reconstructed into an arch shape, allowing lateral thoracic mobility. The patient recovered well and did not experience respiratory dysfunction or local recurrence but later succumbed to distant metastasis. CONCLUSIONS: In this case, the combination of a titanium plate and a Gore-Tex patch proved effective for reconstructing massive lateral chest wall defects. The approach provided stability, preserved thoracic volume, and allowed for lateral mobility. While the patient achieved a successful outcome in terms of local recurrence and respiratory function, distant metastasis remained a challenge for myxofibrosarcoma patients, and its impact on long-term prognosis requires further investigation. Nevertheless, the described procedure offers promise for managing extensive chest wall defects.

A Single-center Experience of Radiotherapy in Pediatric Ewing Sarcoma/Primitive Neuroectodermal Tumor of the Chest Wall.

AIM: To evaluate the treatment results, prognostic parameters, and treatment-related toxicity in patients with Ewing sarcoma (ES)/primitive neuroectodermal tumor (PNET) of the chest wall who underwent surgery, chemotherapy, and radiotherapy (RT) in a tertiary referral center. METHODS: The data of 24 patients under 18 years of age with a histologic diagnosis of ES/PNET in the chest wall that received RT in our department between February 2003 and July 2020 were retrospectively evaluated. RT was applied to the primary site±whole involved chest wall and to the whole lung in patients with lung metastasis. RESULTS: The median age was 8.5 years (range: 1.5 to 17 y), 15 (63%) patients were female and 9 were male (37%). The tumor localization was extrathoracic in 18 (75%) and intrathoracic in 6 (25%) patients. Mediastinal lymph node and distant metastasis (DM) was present in 5 (21%) and 4 (16%) cases at diagnosis, respectively. The median follow-up after RT was 47 months (range: 11 to 162 mo). The 2-year and 5-year overall survival, event-free survival, local recurrence-free survival, and pleural recurrence-free survival were 83% and 48%, 48% and 42%, 74% and 48%, and 61% and 52%, respectively. The overall local control rate was 83% and the pleural control rate was 67%. RT was well tolerated, with 1 case of grade 3 acute dermatitis and 1 case of grade 3 subacute radiation pneumonitis. Late toxicity was observed in 3 (13%) cases. CONCLUSION: Long-term survival can be achieved with extended-field RT even in patients with ES/PNET of the chest wall with DM. The low toxicity rates allow us to draw the conclusion that RT with modern techniques is an effective and safe treatment modality for these patients.

Surgical Resection of Giant Chest Wall Chondrosarcoma Combined with Sandwich Chest Wall Reconstruction in One Case.

INTRODUCTION: Primary chest wall tumors account for 5% of all thoracic neoplasms and 1% of all primary tumors. Chondrosarcoma is a rare solid tumor, with an annual incidence of <0.5 per million people per year. It predominantly occurs in the pelvis and femur, occasionally occurs in flat bones such as the sternum and ribs, and rarely invades lung tissue. Chest wall chondrosarcomas represent only 5-15% of all chondrosarcomas. Radical surgery often leads to a large range of chest wall defects, especially when the range exceeds 6 cm × 6 cm and involves the sternum, spine, or multiple consecutive ribs. The reconstruction of the chest wall bone should be considered to restore the integrity and stability of the chest, prevent chest wall softening and abnormal breathing, and ensure the stability of respiratory circulation. Chest wall reconstruction can help restore thoracic hardness and integrity, prevent lung hernia and abnormal breathing, while also ensuring a positive aesthetic outcome. The chest wall reconstruction includes reconstruction of the pleura, bony structures, and soft tissues. CASE REPORT: In our case of an adult male, after the resection of the third and fourth anterior rib chondrosarcoma, the common anatomical plate was shaped and fixed to the stump of the third rib with screws to ensure the stability of the thorax while retaining the mobility of the thorax. After applying hernia mesh pruning, the chest wall defect was stitched to complete the pleural reconstruction of the defect area. This procedure can effectively maintain the stability of the pleural cavity, provide more effective support for the chest wall soft tissue, and promote the recovery of upper limb function and lung function. CONCLUSION: The radical surgery of giant chest wall chondrosarcoma often leads to a large range of chest wall defects. Chest wall reconstruction needs to be carried out at the same time to restore the integrity and stability of the chest wall, to avoid chest wall softening and abnormal breathing, and to ensure the stability of respiratory circulation. Using the "sandwich" method for chest wall reconstruction, in which an anatomical plate is combined with hernia mesh and muscle soft tissue, and during which pleura, bony structure, and soft tissues are reconstructed, can provide more effective support for chest wall soft tissue, effectively prevent postoperative muscle tissue collapse, avoid postoperative abnormal breathing, and promote the recovery of postoperative upper limb function and lung function. It is a very effective method for chest wall reconstruction.

[Analysis of Influencing Factors of Complications for CT-guided 
Percutaneous Lung Biopsy].

BACKGROUND: Computed tomography guided percutaneous lung biopsy (CT-PLB) is a widely used method for the diagnosis of lung lesions. However, it is invasive, and the most common complications are pneumothorax and pulmonary hemorrhage, which can be life-threatening in severe cases. Therefore, the aim of this study is to analyze the independent risk factors affecting the occurrence of different complications of CT-PLB, so as to reduce the incidence of complications. METHODS: The 605 patients with complete clinical data who underwent CT-PLB in our hospital from May 2018 to December 2019 were retrospectively analyzed. According to the location of the lesions, they were divided into subpleural group and non-subpleural group. The patients were divided into pneumothorax group, pulmonary hemorrhage group, pneumothorax with pulmonary hemorrhage group and non-pneumothorax/pulmonary hemorrhage group according to the complications. The risk factors affecting the incidence of different complications and the independent risk factors of each complication were analyzed. RESULTS: The incidence of pneumothorax was 34.1%, the incidence of pulmonary hemorrhage was 28.1%, and the incidence of pneumothorax complicated with pulmonary hemorrhage was 10.8% (63 cases). The independent risk factor affecting the incidence of subpleural pneumothorax was lesion size (P=0.002). The independent risk factors affecting the occurrence of pneumothorax in the non-subpleural group were plain scan CT value (P=0.035), length of needle through lung tissue (P=0.003), and thickness of needle through chest wall (P=0.020). Independent risk factors affecting the occurrence of pulmonary hemorrhage in the non-subpleural group were length of needle through lung tissue (P<0.001), △CT value of needle travel area (P=0.001), lesion size (P=0.034) and body position (P=0.014). The independent risk factors affecting the co-occurrence of pneumothorax and pulmonary hemorrhage were the length of needle through lung tissue (P<0.001) and the △CT value of needle travel area (P<0.001). CONCLUSIONS: CT-PLB is a safe and effective diagnostic method, which of high diagnostic value for lung lesions. Selecting the appropriate puncture program can reduce complications such as pneumothorax and pulmonary hemorrhage, and improve diagnosis and treatment efficiency.

Mind the gap! Interdisciplinary approach to anterior chest wall reconstruction after total sternectomy.

BACKGROUND: There are various reconstructive methods after total sternectomy. Reproducibility is scarce due to overall small patient numbers. Therefore we present a standardized, interdisciplinary approach for thoracic and plastic surgery. METHODS: Four patients underwent interdisciplinary chest wall reconstruction with STRATOS® titanium bars and myocutaneous vastus lateralis muscle free flap in our center. RESULTS: All patients reported chest wall stability after reconstruction. They reported good quality of life, no dyspnea, prolonged pain or impairment in lung function from rigid reconstruction. FEV1/FVC was overall better after surgery. Secondary wound healing was not impaired and there was no implant defect in follow up. CONCLUSIONS: We recommend an interdisciplinary surgical approach in chest wall reconstruction after total sternectomy. The combination of rigid reconstruction with titanium bars and a myocutaneous vastus lateralis muscle free flap renders excellent results in patient satisfaction and is objectifiable via spirometry.

Chest wall resection with robotic-assisted thoracoscopic surgery for a Pancoast tumour: a case report.

We describe a rare procedure involving near-total robotic-assisted thoracoscopic surgery resection of a right posterior Pancoast tumour. Four ports and an assistant port were used. The DaVinci X system was used. The lobectomy was performed first to allow for adequate exposure to the apex and spine. The lateral aspect of ribs 1 to 4 was resected next, and the extrathoracic space was entered. Dissection proceeded through this space superiorly up to the level of the scapula and then posteriorly towards the spine. The second to the fifth ribs were dissected off the chest wall and resected medially off the spine at the rib heads. Further postero-superior exploration revealed the tumour to be invading the transverse process of the second rib, with ill-defined margins. Because of this development, and with the support of the spinal surgeons, a small high posterior thoracotomy was performed to complete the procedure and remove the specimen en bloc. The postoperative recovery was uneventful, and the patient was discharged on post-operative day 5. The final histological report confirmed a squamous non-small-cell lung cancer (pT3N0M0) with negative margins (R0). Asymptomatic recurrence was noted near the margin of the second rib resection posteriorly 1 year postoperatively and was successfully treated with radiotherapy.

Microsurgical reconstruction using thoracoacromial vessels as recipients for complicated chest wall defects.

BACKGROUND: Free tissue transfer is often required for the reconstruction of complex and deep anterior chest wall wounds, for which the identification of suitable recipient vessels is crucial. Although the internal mammary arteries (IMAs) are a representative option, identifying secondary options when these vessels are compromised remains a challenge. This report evaluated the efficacy of using the thoracoacromial vessels (TAVs) as recipients for chest wall reconstruction by reviewing our experience. METHODS: We conducted a retrospective review of patients undergoing free-flap-based chest wall reconstruction using TAVs as recipient vessels from February 2020 to March 2023. Patient demographics and surgery-related characteristics data were collected. The primary outcome of interest was the occurrence of flap perfusion-related complications. RESULTS: In total, 12 cases utilized TAVs as recipients, primarily for defects following sternotomy, where bilateral IMA was unavailable due to prior surgery. The TAVs with reliable perfusion were consistently identified beneath the pectoralis major muscle. The anterolateral thigh flap was predominantly employed, with musculocutaneous or chimeric flaps introduced for bony defects. The mean pedicle length of the harvested flap was 7.2 cm (range, 3-13), and in cases with a vascular gap, the pedicle was extended using an arteriovenous interposition graft. This resulted in a mean pedicle length needed to reach recipient vessels of 9.9 cm (range, 6.5-19). All flaps survived, with only one experiencing partial necrosis. CONCLUSIONS: The TAV could be considered as an attractive alternative recipient vessel in microsurgical reconstruction of complicated chest wall defects when the use of IMA is not feasible.

Impact of delayed removal of pectus bar on outcomes following Nuss repair: a retrospective analysis.

BACKGROUND: Usually, pectus bars are removed 3 years after the Nuss procedure in patients with pectus excavatum. However, the optimal timing for postoperative pectus bar removal remains undefined. Our study investigated the effects of delayed pectus bar removal after Nuss repairs. METHODS: Retrospective data were collected on patients who underwent Nuss procedures for pectus excavatum and had their bars removed from August 2014 to December 2020. Patients with correction periods > 3 years were divided into group A (< 6 years) and group B (≥ 6 years). Propensity score matching was used to compare complications and radiological outcomes associated with bar removal. RESULTS: Of the 542 patients who underwent bar removal, 451 (Group A: 419 patients, Group B: 32) had correction duration > 3 years. The average correction duration was 4.5 ± 1.4 years. After propensity score matching analysis, group B [median duration: 8.0 (6.0-16.2) years] exhibited significantly longer median operative times (85 vs. 55 min; P = 0.026), higher callus formation rates (68.8% vs. 46.9%; P = 0.029), and greater median intraoperative blood loss (35 vs. 10 mL; P = 0.017) than group A [median duration: 4.2 (3.0-5.9) years]. However, following bar removal, the groups showed no statistical differences in the surgical complication rates (group A: 6.3% vs. group B: 9.4%; P = 0.648) or median ratio of radiological improvement (an improvement on the Haller index on chest radiography; 21.0% vs. 22.2%; P = 0.308). CONCLUSIONS: Delaying pectus bar removal after Nuss repair presents certain challenges but does not compromise overall outcomes. These findings suggest that a longer correction period may be unnecessary. However, further multicenter studies with long-term follow-up are warranted to assess long-term outcomes.

An innovative reconstruction of an enbloc resected composite giant chest and abdominal wall chondrosarcoma with 3D-composite mesh.

BACKGROUND: Chest wall chondrosarcomas, although common, pose unique challenges due to their aggressive nature, rarity of abdominal wall involvement, and propensity for recurrence. We highlight the critical role of meticulous surgical planning, multidisciplinary collaboration, and innovative reconstruction techniques in achieving optimal outcomes for patients with composite giant chest and abdominal wall chondrosarcoma. CASE PRESENTATION: A 38-year-old female patient presented with progressive left chest and abdominal wall swelling for two years; on evaluation had a large lobulated lytic lesion arising from the left ninth rib, scalloping eighth and tenth ribs measuring 13.34 × 8.92 × 10.71 cm (anteroposterior/transverse/craniocaudal diameter) diagnosed with chondrosarcoma grade 2. A three-dimensional (3D) composite mesh was designed based on computed tomography using virtual surgical planning and computer-assisted design and manufacturing technology. She underwent wide local excision and reconstruction of the chest and abdominal wall with 3D-composite mesh under general anesthesia. The postoperative condition was uneventful, with no recurrence at 12 months follow-up. CONCLUSION: A 3D-composite mesh facilitates patient-specific, durable, and cost-effective chest and abdominal wall reconstruction.

Screening chest wall ultrasound in the mastectomy patient.

BACKGROUND: While there are clear guidelines regarding chest wall ultrasound in the symptomatic patient, there is conflicting evidence regarding the use of ultrasound in the screening of women post-mastectomy. OBJECTIVE: To assess the utility of screening chest wall ultrasound after mastectomy and to assess features of detected malignancies. METHODS: This IRB approved, retrospective study evaluates screening US examinations of the chest wall after mastectomy. Asymptomatic women presenting for screening chest wall ultrasound from January 2016 through May 2017 were included. Cases of known active malignancy were excluded. All patients had at least one year of clinical or imaging follow-up. 43 exams (8.5 %) were performed with a history of contralateral malignancy, 465 exams (91.3 %) were performed with a history of ipsilateral malignancy, and one exam (0.2 %) was performed in a patient with bilateral prophylactic mastectomy. RESULTS: During the 17-month period, there were 509 screening US in 389 mastectomy patients. 504 (99.0 %) exams were negative/benign. Five exams (1.0 %) were considered suspicious, with recommendation for biopsy, which was performed. Out of 509 exams, 3 (0.6 %) yielded benign results, while 2 (0.39 %) revealed recurrent malignancy, with a 95 % confidence interval (exact binomial) of 0.05 % to 1.41 % for screening ultrasound. Both patients who recurred had previously recurred, and both had initial cancer of lobular histology. CONCLUSION: Of 509 chest wall screening US exams performed in mastectomy, 2 malignancies were detected, and each patient had history of invasive lobular carcinoma and at least one prior recurrence prior to this study, suggesting benefit of screening ultrasound in these populations.

Inter-institutional variability of knowledge-based plan prediction of left whole breast irradiation.

PURPOSE: Within a multi-institutional project, we aimed to assess the transferability of knowledge-based (KB) plan prediction models in the case of whole breast irradiation (WBI) for left-side breast irradiation with tangential fields (TF). METHODS: Eight institutions set KB models, following previously shared common criteria. Plan prediction performance was tested on 16 new patients (2 pts per centre) extracting dose-volume-histogram (DVH) prediction bands of heart, ipsilateral lung, contralateral lung and breast. The inter-institutional variability was quantified by the standard deviations (SDint) of predicted DVHs and mean-dose (Dmean). The transferability of models, for the heart and the ipsilateral lung, was evaluated by the range of geometric Principal Component (PC1) applicability of a model to test patients of the other 7 institutions. RESULTS: SDint of the DVH was 1.8 % and 1.6 % for the ipsilateral lung and the heart, respectively (20 %-80 % dose range); concerning Dmean, SDint was 0.9 Gy and 0.6 Gy for the ipsilateral lung and the heart, respectively (<0.2 Gy for contralateral organs). Mean predicted doses ranged between 4.3 and 5.9 Gy for the ipsilateral lung and 1.1-2.3 Gy for the heart. PC1 analysis suggested no relevant differences among models, except for one centre showing a systematic larger sparing of the heart, concomitant to a worse PTV coverage, due to high priority in sparing the left anterior descending coronary artery. CONCLUSIONS: Results showed high transferability among models and low inter-institutional variability of 2% for plan prediction. These findings encourage the building of benchmark models in the case of TF-WBI.

Is pregnancy safe with an implanted pectus bar? An uneventful pregnancy with implanted pectus bar following correction of pectus excavatum.

Limited data are available on the implications on pregnancy following pectus bar implantation for correction of pectus excavatum (Nuss procedure), while the pectus bars are in place. Limited data is also available on long-term reproductive implications following pectus bar removal.Providers at times need to consider the necessity to counsel a woman desiring pectus excavatum correction and pregnancy whether to postpone one of the two in favour of the other.We present the case of a woman of reproductive age with an uneventful pregnancy and delivery while carrying an implanted pectus bar and subsequent uneventful pregnancy and delivery after bar removal.

Blunt mechanism chest wall injury: initial patient assessment and acute care priorities.

Blunt mechanism chest wall injury (CWI) is commonly seen in the emergency department (ED), since it is present in around 15% of trauma patients. The thoracic cage protects the heart, lungs and trachea, thereby supporting respiration and circulation, so injury to the thorax can induce potentially life-threatening complications. Systematic care pathways have been shown to improve outcomes for patients presenting with blunt mechanism CWI, but care is not consistent across the UK. Emergency nurses have a crucial role in assessing and treating patients who present to the ED with blunt mechanism CWI. This article discusses the initial assessment and acute care priorities for this patient group. It also presents a prognostic model for predicting the probability of in-hospital complications following blunt mechanism CWI.

Growth of the brachial nerve plexus with reference to topographical relation of the medianus nerve ansa with the thoracic wall and shoulder: a histologic study using human embryos and fetuses.

BACKGROUND: There is currently no information on positional changes in the brachial nerve plexus during prenatal growth. The subclavian-axillary artery passing through the medianus nerve ansa is considered a good landmark for evaluating the height of the plexus. MATERIALS AND METHODS: We used histologic sections from 9 embryos and 17 fetuses (approximately 6-15 weeks of gestational age) to identify the height of the ansa by referring to the level of the rib and the glenohumeral joint. RESULTS: The nerve ansa was usually (23 plexuses) observed at the level of the first and/or second ribs. However, it was sometimes observed above the first rib, at a distance equal to or more than an intercostal width (7 plexuses). In the latter group, the ansa was usually located below the glenohumeral joint. Thus, the joint was located higher than the first rib, although the upper extremities were in the anatomic position for all specimens. The left-right difference in the height of the plexus corresponded to or was less than the width of the first intercostal space. Despite the synchronized growth between the thorax and shoulder girdle, the brachial plexus showed a considerable variation in comparative height; the range corresponded to twice of an intercostal width. Whether the nerve plexus is located high or low is determined at an early developmental stage and is maintained during the later growth stages. CONCLUSION: The high-positioned plexus might cause nerve injury at delivery, followed by a glenohumeral joint deformity because of the fragility without fixation in the thorax.