Muscle origins, insertions, actions - thoracic cavity Flashcards
Scalenus
Origin: Transverse processes
Insertion: first rib
Action: Inspiration
Serratus ventralis (cervicis, thoracis)
Origin: neck and thorax
Insertion: Serrated face of scapula
Serratus dorsalis (cranialis)
Origin: Aponeurosis deep to the rhomboideus
Insertion: Thorax
Action: Lifts ribs for inspiration
Serratus dorsalis (caudalis)
Origin: Aponeurosis from thoracolumbar fascia
Insertion: caudal borders of last 3 ribs
Action: Draws last 3 ribs caudally in expiration
External intercostal muscle
Action: Draw ribs together (effect depends on fixation of rib cage)
Internal intercostal muscle
Action: Draw ribs together for respiration
External abdominal oblique
Origin: Thoracolumbar fascia
Inserts: Linea alba, aponeurosis of external abdominal oblique forms external lamina
What forms the superficial inguinal ring?
External lamina
What is the inguinal canal?
Canal from deep inguinal ring to superficial inguinal ring
What is located within the vaginal process?
Round ligament of the uterus
Where is the inguinal ligament?
Runs caudal to the external lamina
Internal abdominal oblique
Origin: Superficial leaf of thoracolumbar fascia
Insertion: Aponeurosis on costal arch and linea alba
Transverse abdominus
Origin: Thoracolumbar fascia
Insertion: Linea alba
Forms internal lamina
Rectus abdominus
Extends from pecten of the pubis to the sternum
Action: Flexes thoracolumbar part of vertebral column
