Rhomboid major muscle
|Muscles connecting the upper extremity to the vertebral column. (Rhomboideus major visible at upper center right, near shoulder.)|
|Latin||musculus rhomboideus major|
|Gray's||subject #121 434|
|Origin:||spinous processes of the T2 to T5 vertebrae|
|Insertion:||medial border of the scapula, inferior to the insertion of rhomboid minor muscle|
|Artery:||dorsal scapular artery|
|Nerve:||dorsal scapular nerve (C4 and C5)|
|Action:||Retracts the scapula and rotates it to depress the glenoid cavity. It also fixes the scapula to the thoracic wall.|
|Antagonist:||Serratus anterior muscle|
The rhomboid major arises from the spinous processes of the thoracic vertebrae T2 to T5 as well as the supraspinous ligament. It inserts on the medial border of the scapula, from about the level of the scapular spine to the scapula's inferior angle.
The rhomboid major is considered a superficial back muscle. It is deep to the trapezius, and is located directly inferior to the rhomboid minor. As the word rhomboid suggests, the rhomboid major is diamond-shaped. The major in its name indicates that it is the larger of the two rhomboids.
The rhomboid major, like the rhomboid minor, is innervated by the dorsal scapular nerve (C5).
The rhomboid major helps to hold the scapula (and thus the upper limb) onto the ribcage. It also acts to retract the scapula, pulling it towards the vertebral column.
This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.