Iliocostalis

Iliocostalis

Diagram of the iliocostalis muscle

The iliocostalis is a muscle that is part of the erector spinae muscle group, which is responsible for the extension and lateral flexion of the vertebral column. It is one of the three muscles that make up the erector spinae, the others being the longissimus and the spinalis.

Anatomy

The iliocostalis muscle is divided into three parts based on their location along the spine:

Iliocostalis lumborum

The iliocostalis lumborum is the most inferior part of the iliocostalis muscle. It originates from the sacrum, the iliac crest, and the spinous processes of the lower lumbar vertebrae. It inserts into the lower six ribs.

Iliocostalis thoracis

The iliocostalis thoracis is located in the thoracic region. It originates from the lower six ribs and inserts into the upper six ribs.

Iliocostalis cervicis

The iliocostalis cervicis is the most superior part of the iliocostalis muscle. It originates from the upper six ribs and inserts into the transverse processes of the lower cervical vertebrae.

Function

The primary function of the iliocostalis muscle is to extend and laterally flex the vertebral column. It plays a crucial role in maintaining posture and allowing for movements such as bending sideways and rotating the spine.

Innervation

The iliocostalis muscle is innervated by the dorsal rami of the spinal nerves. These nerves provide the necessary motor signals for muscle contraction and sensory feedback from the muscle.

Blood supply

The blood supply to the iliocostalis muscle comes from the intercostal arteries and the lumbar arteries, which provide oxygenated blood to the muscle fibers.

Clinical significance

The iliocostalis muscle can be involved in various clinical conditions, such as back pain and muscle strain. Proper functioning of this muscle is essential for maintaining a healthy posture and preventing spinal injuries.

Related pages

• Erector spinae
• Longissimus
• Spinalis
• Vertebral column
• Back pain