What is Rhomboid Muscle?
The rhomboid muscles are a pair of muscles—the rhomboid major and the rhomboid minor—located in the upper back, between the shoulder blades. They are crucial for upper limb movement and maintaining the stability of both the shoulder girdle and scapula (shoulder blade).
- Location: The rhomboids are situated deep to the trapezius muscle, forming parallel bands that run inferolaterally (downward and towards the side).
- Origin and Insertion: The rhomboid minor originates from the spinous processes of the seventh cervical and first thoracic vertebrae (C7-T1), while the rhomboid major originates from the spinous processes of the second to fifth thoracic vertebrae (T2-T5). Both muscles insert onto the medial border of the scapula (shoulder blade).
- Innervation: Both rhomboids are innervated by the dorsal scapular nerve.
- Blood Supply: The dorsal scapular artery provides the blood supply.
- Function: Their primary function is to retract the scapula (pulling the shoulder blades together), rotate it downward, and stabilize it against the thoracic cage. This action is essential for various movements, including arm and shoulder movements.
Rhomboid Muscle Pain
Pain in the rhomboid muscles can result from various causes, including:
- Injury: Direct trauma to the muscles can cause pain and inflammation.
- Strain: Overuse or sudden strenuous activity can strain the rhomboids.
- Poor Posture: Maintaining poor posture for extended periods can lead to muscle imbalances and pain.
Rhomboid muscle pain often manifests as tenderness around the shoulder blade, and it may be accompanied by stiffness and limited range of motion. Treatment typically involves rest, ice, over-the-counter pain relievers, and physical therapy exercises. In severe cases, medical attention may be required.
Clinical Significance
Rhomboid muscle paralysis, a rare condition resulting from dorsal scapular nerve neuropathy, can cause scapular winging (the shoulder blade protrudes from the back). Conversely, the rhomboid major muscle has even been used successfully in surgical procedures such as esophageal repair, demonstrating its robust blood supply and versatility.
