This fascia covers the deep muscle of the back , i.e the erector spinae. It is divided into cervical, thoracic and lumbar parts. The lumbar part is trilaminar with posterior, anterior and intermediate layer..
1. Cervical part - continuous with deep fascia of back
2. Thoracic part- Attached medially to thoracic spines and laterally to costal angles.
3. Lumbar part
Posterior layer is attached to lumbar and sacral spines and supraspinous ligaments. Middle is attached to the lumbar transverse process and intertransverse ligaments and also superiorly to the iliolumbar ligament and inferiorly to the lower border of 12th rib and lumbocostal ligament. Anterior layer is attached medially to the lumbar transverse process and superiorly to the lateral arcuate ligament and below to iliolumbar ligament and iliac crest.
DISTAL ATTACHMENT: As above. The lumbar trilaminar parts join to form the conjoint lamellae of thoracolumbar fascia which provides attachments for transversus abdominis and internal oblique muscle of abdomen.
FUNCTION: Covers the muscles of the back and gives them support through attachment to spine.
JOINT: Vertebrocostal joints