Deep Back and Suboccipital Triangle

Objectives:1.Describe the structure, attachments, function and

support of:

• splenius capitus and cervicis• erector spinae• transversospinal group• intersegmental group

2.Describe the attachments, actions and support of the suboccipital muscles.

3.Describe the boundaries, contents and relationships of the suboccipital triangle.

Thoracolumbar Fascia

The thoracolumbar fascia:

• surrounds the deep muscles of the back

• superiorly, continuous with deep fascia of the neck

• “deep” to serratus posterior muscles

• medially, attaches to the spines of the vertebrae

• laterally, attaches to the transverse processes

• inferiorly, attaches to lower border of 12th rib and iliac crest

Thoracolumbar Fascia

Deep Back Muscles and Innervation

Rotation of Vertebrae

Splenius Cervicis:Attachments:

Action:

Innervation:

Splenius Capitis:Attachments:

Action:

Innervation:

Splenius Cervicis & Capitis

Erector SpinaeSpinalis

Longissimus

Iliocostalis

Erector Spinae

A 35-year-old male presents with the main complaint of lower back discomfort. Physical exam reveals that L1 – L4 are SBL and RR.

Dysfunction of what muscle is most likely responsible for this finding?

(SBL = side bend to the left…Rr = rotated to the right side)…

Transversospinal Group

Rotatores

Multifidus

Semispinalis

Transversospinal Group

Transversospinal Group

Intersegmental Muscles

Interspinales:

Intertransversarii:

Intersegmental MusclesIntertransversarii: in the thoracic region intertransversarii are

modified to form the levator costarum

Suboccipital Muscles

• situated deep to semispinalis capitis

Rectus capitis posterior major

Rectus capitis posterior minor

Obliquus capitis inferior

Obliquus capitis superior

Contents of the Suboccipital Triangle

Contents of the Suboccipital Triangle