Exam 3 Flashcards
(202 cards)
psoas origin
transverse processes of all lumbar vertebrae, sides of vertebral bodies and intervertebral discs from T12 to L5
psoas insertion
fibers run inferiorly and laterally; leave abdomen and enter thigh by passing under inguinal ligament; end in a tendon that inserts into lesser trochanter of femur
psoas innervation
ventral rami of L1 to L3 spinal nerves
psoas actions
flexes thigh at hip joint; if thigh is fixed, it flexes trunk
iliacus origin
iliac fossa
iliacus insertion
fibers converge to insert into lateral side of tendon of psoas major muscle, which ends in lesser trochanter of femur (combined muscles are referred to as iliopsoas)
iliacus innervation
femoral nerve
iliacus actions
flexes thigh at hip joint; if thigh is fixed, it flexes trunk
psoas minor
absent in about 40% of individuals
located entirely within abdomen, anterior to psoas major muscle
psoas minor origin
sides of vertebral bodies of T12 and L1 and intervertebral disc between them
psoas minor insertion
muscle fibers give rise to a long flat tendon which inserts into iliopubic eminence
psoas minor innervation
ventral rami of L1 and L2 spinal nerves
psoas minor action
weak flexor of trunk
quadratus lumborum origin
iliolumbar ligament and posterior part of iliac crest
quadratus lumborum insertion
fibers run superiorly and medially and insert into inferior border of 12th rib and transverse processes of upper 4 lumbar vertebrae
quadratus lumborum innervation
ventral rami of T12 to L3 (or L4) spinal nerves
quadratus lumborum actions
depresses and fixes 12th rib, holding it down against traction exerted by diaphragm in inspiration
lateral flexion of trunk to same side of contracting muscle (unilateral contraction)
may extend lumbar part of vertebral column (bilateral contraction)
iliolumbar ligament
extends from transverse process of L5 to posterior part of iliac crest
diaphragm sternal part
smallest part; fibers originate from posterior surface of xiphoid process
diaphragm costal part
fibers originate from internal surface of lower 6 ribs and their costal cartilages
diaphragm lumbar part
medially, it originates from 2 vertical tendinous columns right and left crura
right crus attaches to vertebral bodies of upper 3 or 4 lumbar vertebrae and intervertebral discs in between
left crus (shorter) attaches to vertebral bodies of upper 2 or 3 lumbar vertebrae and intervertebral discs in between
medial borders of right and left crura are connected by median arcuate ligament (crosses over anterior surface of aorta)
lateral to crura, muscle fibers of lumbar part originate from medial and lateral arcuate ligaments
medial arcuate ligament
thickened, upper margin of fascia that covers anterior surface of psoas major muscle; extends from body of L2 to tip of transverse process of L1
lateral arcuate ligament
thickened, upper margin of fascia that covers anterior surface of quadratus lumborum muscle; extends from tip of transverse process of L1 to 12th rib
diaphragm anterior view
diaphragm curves up into right and left domes
right dome is slightly higher than left due to large size of right lobe of liver
during expiration, right dome reaches upper border of 5th rib (or 4th intercostal space) and left dome reaches lower border of 5th rib