Name
Pronunciation
(lon-GIS-I-mus tho-RA-sus)
Origin/Proximal Attachment
Transverse processes of lumbar vertebrae; intermediate continuation of erector spinae
Insertion/Distal Attachment
Transverse processes of all thoracic vertebrae; lower 9 or10 ribs between tubercles & angles; transverse processes of upper lumbar vertebrae
Action/Relevance
Extends & laterally flexes vertebral column; can depress ribs
Innervation
Thoracic & lumbar nerves