Dance Anatomy & Kinesiology

86 Dance Anatomy and Kinesiology

Palpation: Sitting on the floor or in a chair, lean forward to relax the abdominal muscles and carefully

press your index and middle fingertips deep into the abdomen about 1 inch (2.5 centimeters) medial

to the front portion of the top of the iliac crest. Then lift the knee toward the chest (hip flexion) on

the same side without leaning back, and you should feel a tightening of the iliopsoas under the more

superficial abdominal wall.

Posterior Muscles of the Spine

The muscles located posterior to the spine (the postvertebral muscles) include muscles that primarily

act on the neck and head (splenius and suboccipital group) and a large number of paired muscles with

the common action of spinal extension. Although many classification schemas exist, this text will use

the classification of these spinal extensors into three groups—the erector spinae, semispinalis, and

deep posterior spinal group. Within these groups, the muscles are arranged from small slips spanning

adjacent vertebrae on the deepest level (deep posterior spinal group) to progressively larger slips with

the semispinalis and erector spinae. This arrangement allows for complex fine coordination with the

smaller slips and yet large force production with the longer slips.

Attachments and Primary Actions of Erector Spinae

Muscle Inferior attachment(s) Superior attachment(s) Primary action(s)

Spinalis

Spinalis cervicis

(spi-NA-lis ser-VIS-us)

Spinous processes of C7

(sometimes T1-2)

Spinous processes

of C2-C4

Spinal extension

Spinal lateral flexion (same)

Spinalis thoracis

(spi-NA-lis tho-RA-sis)

Spinous processes

T11-L2

Spinous processes

of upper thoracic

vertebrae (T1-4 or T8)

Spinal extension

Spinal lateral flexion (same)

Longissimus

Longissimus capitis

(lon-JIS-i-mus kah-PIT-us)

Transverse processes

of T1-4 or T5, articular

processes of C4 or C5-7

Inferior, lateral skull

(mastoid process)

Extension of head

Lateral flexion of head and

C spine (same)

Rotation of head (same)

Longissimus cervicis

(lon-JIS-i-mus ser-VIS-us)

Transverse processes

of T1-4 or T6

Transverse processes

of C2-6

C spinal extension

C spinal lateral flexion

(same)

C spinal rotation (same)

Longissimus thoracis

(lon-JIS-i-mus tho-RA-sis)

Lumbar spinous

processes,

thoracolumbar fascia

Transverse processes

of T1-L5, posteromedial

portion of lower 10 ribs

Spinal extension

Spinal lateral flexion (same)

Spinal rotation (same)

Iliocostalis

Iliocostalis cervicis

(il-ee-o-kos-TA-lis ser-VIS-us)

3rd-6th rib angles Transverse processes

of C4-6

Spinal extension

Spinal lateral flexion (same)

Spinal rotation (same)

Iliocostalis thoracis

(il-ee-o-kos-TA-lis tho-RA-sis)

Upper borders of angles

of lower 6 ribs

Angles of upper 6 ribs,

transverse process of C7

Spinal extension

Spinal lateral flexion (same)

Spinal rotation (same)

Iliocostalis lumborum

(il-ee-o-kos-TA-lis lum-BOR-um)

Spinous processes

of T11-L5, posterior

sacrum, iliac crest

Inferior border of angles

of lower 6 or 7 ribs

Spinal extension

Spinal lateral flexion (same)

Spinal rotation (same)