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Concept: Scalene muscles


A 29-year-old woman who worked as a KAATSU (a type of body exercise that involves blood flow restriction) instructor visited our emergency room with a chief complaint of swelling and left upper limb pain. Chest computed tomography (CT) showed non-uniform contrast images corresponding to the site from the left axillary vein to the left subclavian vein; vascular ultrasonography of the upper limb revealed a thrombotic obstruction at the same site, leading to a diagnosis of Paget-Schroetter syndrome (PSS). We herein report our experience with a case of PSS derived from thoracic outlet syndrome (TOS), in a patient who was a KAATSU instructor.

Concepts: Veins of the torso, First rib, Scalene muscles, Medical imaging, Axillary artery, Axillary vein, Subclavian artery, Subclavian vein


Congenital anatomic anomalies and variations are frequent in the thoracic outlet and may be associated with clinical symptoms. Arterial thoracic outlet syndrome (TOS) is characterized by subclavian artery compression and vascular pathology, almost always in the presence of a bony abnormality. We describe here a patient with arterial thromboembolism following a fall on the outstretched arm, who was found to have subclavian artery stenosis and post-stenotic dilatation in the absence of a bony abnormality. Surgical exploration revealed a previously undescribed anomaly in which the subclavian artery passed through the costoclavicular space in front of the anterior scalene muscle, where it was subject to bony compression between the first rib and clavicle. Successful treatment was achieved by scalenectomy, first rib resection and interposition bypass graft reconstruction of the affected subclavian artery. This newly acknowledged anatomical variant adds to our understanding of the diverse factors that may contribute to development of TOS.

Concepts: First rib, Scalenus medius, Human anatomy, Subclavian vein, Subclavian artery, Scalene muscles


[Purpose] The purpose of this study is to determine the effect that secondary postural deformities and chronic postural abnormalities have on lung capacity, as well as correlate the activity of the respiratory muscles. The results provide basic objective data about the forward head posture and respiratory muscle activity that can be used in clinical situations. [Subjects and Methods] The subjects used in this study were 24 patients aged 25 to 35 years old who visited a hospital in Jeollanam-do Province, Korea, between September 2015 and January 2016. The patients were diagnosed with forward head posture because the vertical line between the acromion process and the external acoustic meatus was at least 5 cm. We measured the craniovertebral angle, pulmonary functions, and respiratory muscle activity of the subjects for correlation analysis. [Results] A positive correlation was found between the craniovertebral angle and the forced vital capacity (r=0.63), while a negative correlation was found between the craniovertebral angle and the sternocleidomastoid muscle (r=-0.77). The craniovertebral angle and the anterior scalene muscle showed a negative correlation (r=-0.65). There were positive correlations between the forced vital capacity and the sternocleidomastoid muscle (r=0.71), and between the forced vital capacity and the anterior scalene muscle (r=0.59). [Conclusion] Severe forward head posture increased the activities of the sternocleidomastoid muscles and the anterior scalene muscles, and decreased the forced vital capacity. Thus, it is necessary to develop more efficient interventions for managing forward head posture based on pulmonary function and the activity of the respiratory synergist muscles.

Concepts: Respiratory physiology, Scalenus anterior, Spearman's rank correlation coefficient, Pearson product-moment correlation coefficient, Correlation and dependence, Clavicle, Muscular system, Scalene muscles


Totally subcutaneous intravascular portals have been increasingly used to administer long-term chemotherapy and parental nutrition. The reported complications are rare. Accidental endovascular rupture of a fragment of catheter is one of the most formidable complications of the central vein catheterization. The Authors report a case of deployment of a Port-a-Cath catheter and its percutaneous retrieval. The catheter accidentally detached and migrated from the reservoir of the port-a-cath placed in the left subclavian vein to the right heart cavities through the blood stream. A review of the Literature is also given, focusing on the possible factors responsible for this unusual complication.

Concepts: Scalene muscles, Vein, Artery, Subclavian artery, Subclavian vein, Blood, Central venous catheter, Heart


Central venous catheter (CVC) insertion is associated with many potential complications; malposition of the catheter is one of them. A chest X-ray is routinely done to detect the malposition of catheter, but sometimes it has been seen that X-ray is time-consuming and its accuracy is also low for determining the exact position of the catheter tip. In our case, an ultrasonography (USG)-guided CVC was placed into the right internal jugular vein of the patient. As there was no ECG change obtained during insertion of guidewire and catheter, malposition was suspected, which was easily detected by a novel USG-guided saline flush test. We present a case report where USG was used for detection of a misplaced CVC (from right internal jugular vein to right subclavian vein). With ultrasound, the location of the catheter tip can be confirmed in very less time compared with chest X-ray.

Concepts: Scalene muscles, Jugular vein, Catheter, Subclavian artery, Brachiocephalic vein, Subclavian vein, Central venous catheter, Internal jugular vein


A persistent left superior vena cava (PLSVC) is rare, but the most common thoracic venous anomaly. We report a case of PLSVC unrecognized during left subclavian vein catheterization using real-time ultrasound-guided supraclavicular approach.

Concepts: Veins of the torso, Scalene muscles, Vein, Subclavian artery, Subclavian vein, Superior vena cava, Brachiocephalic vein, Inferior vena cava


Neurogenic thoracic outlet syndrome (nTOS) is the most common manifestation of thoracic outlet syndrome (TOS), accounting for more than 95% of cases. It is usually caused by cervical ribs, anomalies in the scalene muscle anatomy or post-traumatic inflammatory changes causing compression of the brachial plexus.

Concepts: Scalene muscles, Case, Thorax, Brachial plexus, Subclavian artery, Human anatomy


Thoracic outlet syndrome (TOS) is a condition arising from compression of the subclavian vessels and/or brachial plexus. Many factors or diseases may cause compression of the neurovascular bundle at the thoracic outlet. We describe the case of a 41-year-old woman with TOS who presented with vascular venous symptoms. Chest computed tomography (CT) scan showed a cystic mass at the level of cervico-thoracic junction, located between the left subclavian artery and vein, which appeared compressed. The cystic mass was removed through a cervical approach and it was found to be a cyst arising from the thoracic duct compressing and anteriorly dislocating the left subclavian vein. After surgery symptoms promptly disappeared.

Concepts: Brachiocephalic artery, Vertebral artery, Thoracic outlet syndrome, First rib, Scalene muscles, Axillary artery, Subclavian vein, Subclavian artery


Maintaining vascular access by means of radiological intervention has become the mainstay of management of patients with central venous stenoses and occlusions (CVO), which can be challenging. We present a case of balloon-assisted percutaneous puncture of an occluded left subclavian vein, through a thrombosed arteriovenous graft, for a tunneled dialysis catheter insertion.

Concepts: Vein, Central venous catheter, First rib, Scalene muscles, Hemodialysis, Subclavian artery, Subclavian vein


We report the case of a 73-year-old man with severe edema of the right upper extremity. Computed tomography, magnetic resonance imaging, and venography revealed an intravenous tumor in the middle portion of the right subclavian vein. The tumor was completely resected, and an accompanying thrombus was also removed using the transmanubrial osteomuscular sparing approach. The patient recovered well without any complications or recurrence. The histopathologic diagnosis was intravenous lobular capillary hemangioma, which is also called pyogenic granuloma. To our knowledge, this is the first reported surgical case involving this type of benign tumor originating in a thoracic vein.

Concepts: Radiology, First rib, Lymphatic system, Scalene muscles, Magnetic resonance imaging, Subclavian artery, Subclavian vein, Medical imaging