Abdomen Flashcards
What is the rectus sheath
The aponeurotic attachments of the external oblique, internal oblique and transversus abdominis form a sheath of connective tissue which encases the rectus abdominis muscles
Where does the linea alba run from?
vertically from the xiphoid process to the symphysis pubis
the 2 rectus abdominis muscles are separated by what?
Linea Alba
What is the lateral border of the rectus abdominis and its sheath called?
linea semilunaris
What are the two muscles in the posterior wall?
Psoas Major Quadratus Lumborum (QL)
Quadratus Lumborum
attachments and actions
Sup attach: medial 1/2 of rib 12, TVPs of lumbar vertebrae
Inferior attachment: Iliac crest, iliolumbar ligament
action: bilaterally extends the lumbar spine
action: bilaterally fixes 12th rib during forced expiration
action: stabalizes lumbar spine
action: unilateral lateral flexion and hip hike
What is The region below the pelvic cavity called?
The perineum
What is the floor of the perineum?
What is the roof?
floor: skin
roof: pelvic diaphragm
what muscles are part of the pelvic diaphragm?
levator ani muscles (two) coccygeus muscles (two)
Levator ani attachments
anterior attachment: back of pubis, spine of ischium
posterior attachment: anococcygeal ligament, lower sacrum and coccyx
coccygeus attachments
lateral attachment: pelvic surface of the ischial spine and sacrospinous ligament
medial attachment: lateral margin of coccyx and S5
What are the actions of the pelvic diaphragm?
supports the pelvic viscera, helps maintain control of bodily functions.
Where is the abdomen located?
Between the diaphragm and the pelvis
How many quadrants is the diaphragm divided into?
What are the dividing lines based on?
4 : RUQ: right upper quadrant LUQ: left upper quadrant RLQ: right lower quadrant LLQ: left lower quadrant
Based on the mid-sagital plane and the transumbilical plane (transverse plane passing through the umbilicus or belly button)
What are the 4 anterior abdominal muscles?
Rectus abdominis
external obliques
internal obliques
transversus abdominis
Reclusive abdominis
Attachments, actions, fibre direction
Superior attach: costal cartilage of ribs 5-7, xiphoid process
Inferior attach: pubic symphysis and pubic crest
Action: flexes vertebral column
Action: stabilizes pelvis during lower leg (to allow hip to eccentrically contract)
Action: compresses the viscera
Fibre direction: vertical
External oblique
Most superficial
Superior/lateral attach: ribs 5-12
Inferior/ medial attach: Linea Alba (via abdominal aponeurosis), pubic tubercle, anterior 1/2 of iliac crest
Fibre direction: anteriorly and inferomedially
Action: unilateral rotates column to contralateral side
Action: ipsilateral lateral flexion
Action: bilateral trunk flexion
Action: Bilateral stabilizes pelvis during leg lower
Action: Compress and supports viscera
Reclusive abdominis
Attachments, actions, fibre direction
Superior attach: costal cartilage of ribs 5-7, xiphoid process
Inferior attach: pubic symphysis and pubic crest
Action: flexes vertebral column
Action: stabilizes pelvis during lower leg (to allow hip to eccentrically contract)
Action: compresses the viscera
Fibre direction: vertical
External oblique
Most superficial
Superior/lateral attach: ribs 5-12
Inferior/ medial attach: Linea Alba (via abdominal aponeurosis), pubic tubercle, anterior 1/2 of iliac crest
Fibre direction: anteriorly and inferomedially
Action: unilateral rotates column to contralateral side
Action: ipsilateral lateral flexion
Action: bilateral trunk flexion
Action: Bilateral stabilizes pelvis during leg lower
Action: Compress and supports viscera
Upper fibres interdigitate with serratus anterior
Lower fibres interdigitate with latissimus dorsi
Internal oblique
Attachment
Actions
Fibre direction
Inferior/ Lat attach: anterior 1/2 of iliac crest
Superior/ medial attach: Linea Alba (via aponeurosis), ribs 10-12 (inferior border)
Deep to external oblique
Fibre direction: anteriorly and superomedially
Action: unilateral rotates column to ipsilateral side
Action: ipsilateral lateral flexion
Action: trunk flexion
Action: compress and support viscera
Transversus abdominis
Lateral attach: inner iliac crest, lower 6 costal cartilages, thoracolumbar fascia
Medial attach: Linea Alba (via aponeurosis)
Deep to internal obliques
Fibre direction: medial/ lateral
Action: compress and supports viscera (eg forced expiration, coughing, sneezing, peeing)
Interdigitates with diaphragm
