ANAT 315 Lecture Notes - Lecture 4: Semispinalis Muscles, Erector Spinae Muscles, Iliac Crest

• School: Queen's University
• Department: Anatomy and Cell Biology
• Course: ANAT 315
• Professor: Easteal, Ron

Document Summary

Superficial extrinsic muscles are superficial to these erector spinae origin: sacrum, spinous processes of lumbar and lower thoracic vertebrae, iliac crest keep the body erect. 3 sets of muscles from medial to lateral: spinalis attached to the spine runs up the center line longissimus lateral to spinalis sacrum up iliocostalis ilium up. Deep transversospinalis muscles attached to the transverse processes and spinous processes a few levels up approx. 20 of them lie deep the most medial column of erector spinae small slips of muscle running down the spine help with posture and produce localized lateral rotation. Blood supply mutiple pairs of arteries take origin from the thoracic and abdominal aorta. Venous drainage veins form plexuses that allow blood flow. Innervation all vertebral muscles are innervated by the dorsal rami exit from the intervertebral foramina posterior horn dorsal root spinal nerve dorsal ramus ventral ramus anterior horn ventral root. Dorsal root -> sensory information in and to the brain.