Lumbar Spine Flashcards
Multifidus
Origin: Sacrum, origin of erector spinae, posterior superior iliac spine, posterior SIJ ligament, mammillary processes of lumbar vertebrae, transverse processes of thoracic vertebrae and articular processes of lower four cervical vertebrae
Insertion: Base of spinous processes of all verterae from L5 -C2
Innervation: Medial branch of the dorsal rami of segmental spinal nerves
Function: Stabilizes vertebrae in local movements of the vertebral column.
Global movements – Contract bilaterally to extend the vertebral column
Contract unilaterally to produce rotation in opposite direction and lateral flexion in the same direction
Erector Spinae Muscles
Origin: Arise from a broad thick tendon attached to the sacrum,
spinous processes of the lumbar and lower thoracic vertebrae and iliac crest
Insertion: Divide in the up- per lumbar region into three vertical columns of mus- cle, each which is divided regionally depending on its su- perior attachments
Innervation: Segmental
Function: Primary extensors of the vertebral column and head.
Acting bilaterally they straighten the back, returning it upright from a flexed position
Longissimus Thoracis
Origin: Accessory processes and adjacent medial end of the dorsal sur- face of the transverse processes of lumbar vertebrae, ilium
Insertion: Apices of the trans- verse processes of T1 to T12 and the fourth to twelfth ribs between the tu- bercle and angle
Innervation: Segmental
Function: Primary extensors of the vertebral column and head.
Acting bilaterally they straighten the back, returning it upright from a flexed position
Illiocostalis Lumborum
Origin: Sacrum, spinous processes of lumbar and lower two thoracic vertebrae and their supraspinous ligaments, and the iliac crest
Insertion: Angles of the lower six or seven ribs
Innervation: Segmental
Function: Primary extensors of the vertebral column and head.
Acting bilaterally they straighten the back, returning it upright from a flexed position
