Muscle Anatomy: Abdominal and Pelvic Floor Muscles

Flashcards based on the anatomy and functions of abdominal and pelvic floor muscles.

What are the actions of the Rectus Abdominis?

Flex trunk.

Which muscles contribute to lateral rotation of the thigh?

Obturator internus and Piriformis.

What is the innervation of the Diaphragm?

Phrenic nerve (C3-C5) and lower intercostal nerves (secondarily).

What is the action of the quadratus lumborum when acting unilaterally?

Lateral flexion of the trunk.

Where do the External Abdominal Obliques attach proximally?

Ribs 5-12 and Iliac crest.

What is the distal attachment of the Iliacus?

Lesser trochanter of femur.

Which muscle has the action of aiding in defecation by relaxing?

Levator ani muscles (Puborectalis and Pubococcygeus).

What type of rotation does the Piriformis muscle facilitate?

External/lateral rotation of the hip.

What do the branches of S4 innervate?

Ischiococcygeus and Levator ani muscles.

What stabilizes the lumbar spine and pelvis during bilateral contraction?

Transversus Abdominis.