The rhomboid minor muscle is an extrinsic shoulder muscle located deep to the trapezius and superior to the rhomboid major. It plays an important role in shoulder movements, such as retracting and rotating the scapula. It is innervated by the dorsal scapular nerve and supplied with blood by the dorsal scapular artery.
The rhomboid minor is composed of small muscle fibers that originate from the spinous processes of C7-T1 vertebrae and attach to the medial border of the scapula at the level of its spine.
The major action of the rhomboid minor is to retract the scapula, pulling it medially toward the vertebral column. It also helps to slightly rotate the scapula, bringing its medial border superiorly. This is known as upward rotation of the scapula.
The rhomboid minor is innervated by the dorsal scapular nerve, a branch of the brachial plexus. It is supplied with blood by the dorsal scapular artery, which is a branch of the transverse cervical artery.
The rhomboid minor plays an important role in shoulder movement. Its main action is to retract the scapula, pulling it toward the vertebral column. This retraction is necessary for many shoulder movements, including shoulder abduction, elevation, and flexion. It also helps to stabilize the shoulder blade during dynamic movements such as throwing or pushing.
In addition to shoulder retraction, the rhomboid minor also helps to rotate the scapula. It does this through upward rotation, which brings the medial border of the scapula superiorly and helps to elevate the shoulder. This upward rotation is important for achieving full shoulder elevation.
The rhomboid minor is an important muscle for shoulder movement. Dysfunction of the rhomboid minor can lead to decreased shoulder strength, pain, and difficulty with shoulder abduction and flexion. Weakness in the rhomboid minor can also lead to scapular winging, or when the shoulder blade protrudes from the back of the ribcage due to instability.
Injury to the rhomboid minor can be caused by overuse or trauma. Overuse injuries are more common in athletes who engage in repetitive overhead movements such as throwing or serving. Neck and shoulder trauma, such as a dislocation or fracture, can also lead to rhomboid minor injury.
Treatment for rhomboid minor injury is often non-surgical. Rest, stretches, and strengthening exercises are recommended to improve strength and mobility. A physical therapist can help to assess the injury and develop a rehabilitation program appropriate for the patient’s specific needs.
