Search results
Results From The WOW.Com Content Network
The posterior scalene, (Latin: scalenus posterior) is the smallest and most deeply seated of the scalene muscles. It arises, by two or three separate tendons, from the posterior tubercles of the transverse processes of the lower two or three cervical vertebrae, and is inserted by a thin tendon into the outer surface of the second rib, behind ...
Origin The bone or other structure the muscle is attached to that remains immobile during the action. The term "bone" is omitted from bone names. Insertion The attachment point of the muscle, on a bone or otherwise, that moves during the action. Artery The artery which supplies the muscle with blood.
The long thoracic nerve arises from the anterior rami of cervical spinal nerves C5, C6, and C7. [1] [2] [3] The root from C7 may occasionally be absent. [4]The roots from C5 and C6 pierce through the scalenus medius, while the C7 root passes in front of the muscle.
Sibson muscular part is originated from scalenus medius muscle. Fascial part is originated from Endothoracic Fascia. It attaches to the internal border of the first rib and the transverse processes of vertebra C7.
Its floor is formed from above downward by the Splenius capitis, Levator scapulæ, and the Scalenus medius and posterior. It is covered by the skin, the superficial and deep fasciæ, and by the Platysma below.
The scalene tubercle is a small projection that runs along the medial border of the first rib between two grooves, which travel anteriorly for the subclavian artery and posteriorly for the subclavian vein. It projects outward medially, and is the site of insertion for scalenus anterior. [1] [2]
The number of attachments varies; a slip may extend to the occipital or mastoid, to the trapezius, scalene or serratus anterior, or to the first or second rib. The muscle may be subdivided into several distinct parts from origin to insertion.
On the right side of the neck, the phrenic nerve is separated from the second part of the artery by the scalenus anterior muscle, while on the left side it crosses the first part of the artery close to the medial edge of the muscle. Behind the artery are the pleura and the scalenus medius muscle. Above the artery is the brachial plexus. [4]