Longissimus muscles

The longissimus muscles are a group of muscles that are part of the erector spinae muscle group, which is responsible for the extension and lateral flexion of the spine.

The longissimus muscles are divided into three main parts: longissimus thoracis, longissimus colli muscle (longissimus cervicis), and longissimus capitis muscle. These muscles run longitudinally along the spine and are situated between the iliocostalis and spinalis muscles.

The longissimus thoracis extends from the lumbar region to the thoracic region, the longissimus colli muscle extends from the thoracic to the cervical region, and the longissimus capitis muscle extends from the cervical region to the mastoid process of the skull.

Origin:

• Longissimus capitis: Transverse processes of vertebrae C4-T5

• Longissimus cervicis: Transverse processes of vertebrae T1-T5

• Longissimus thoracis:

  • Lumbar part - Lumbar intermuscular aponeurosis, medial part of sacropelvic surface of ilium, Posterior sacroiliac ligament

  • Thoracic part - Spinous and transverse processes of vertebrae L1-L5,  median sacral crest, posterior surface of sacrum and posterior iliac crest

Insertion:

• Longissimus capitis: Mastoid process of temporal bone

• Longissimus cervicis: Transverse processes of vertebrae C2-C6

• Longissimus thoracis: 

  • Lumbar part - Accessory and transverse processes of vertebrae L1-L5

  • Thoracic part - Transverse process of vertebrae T1-T12, Angles of ribs 7-12

Artery:

• Longissimus capitis and cervicis: vertebral artery, deep cervical artery, occipital artery, transverse cervical artery

• Longissimus thoracis: superior intercostal, posterior intercostal and subcostal arteries; lateral sacral and median sacral arterie

Nerve: Posterior branch of spinal nerve

Antagonist: Rectus abdominis muscle