MSAK lec - midterm 3 Flashcards
which muscles are found in the 6 layers of the back
layer 1: traps & lats
layer 2: rhomboids & levator scapulae
layer 3: serratus posterior superior & inferior
layer 4: spinotransversales - splenius capitis & splenius cervicis
layer 5 - erector spinae - iliocostalis, longissimus, spinalis
layer 6 - transversospinales - semispinalis, multifidus, rotatores
name the fascias of the back
nuchal (cervical, continuous with nuchal ligament) and thoracolumbar (3 layers, over erector spinae, very strong in lumbar region)
what are the 3 layers of thoracolumbar fascia
posterior (SPs, interspinous ligament, median sacral crest attachments), middle (TPs, intertransverse ligaments, iliac crest to 12th rib), & anterior (attaches to TPs and covers anterior QL. very deep. becomes arcuate ligament of diaphragham and blends with transversus abdominis)
where do the erector spinae muscles sit in the thoracolumbar fascia
between posterior and middle layers
which muscles fill the lamina groove
erector spinae (and also transversospinales)
which erector spinae muscle has a lumborum subdivision
iliocostalis
what is the common origin for erector spinae muscles
aponeurosis - lumbar SPs, supraspinous ligament (T11-L5), median sacral crest, sacrotuberous ligament, posterior sacroiliac ligament, lateral sacral crest, posterior iliac crest
what do the erector spinae muscles assist in
extension, lateral flexion, and ipsilateral rotation of trunk, neck, and head. maintaining the lumbar lordosis (anterior pelvic tilt)
which erector spinae muscles attach to the pelvis
iliocostalis lumborum and logissimus thoracis
which erector spinae muscle does not attach to the common origin
spinalis (does not have a lumborum region)
which erector spinae attaches to the mastoid process of the skull
longissimus
describe the transversospinales (layer 6 muscles)
- they course superiomedially (think christmas tree)
- they become shorter from superficial to deep
- primarily postural
describe how semispinalis attaches to vertebrae
runs superiorly 6 or more vertebrae above origin.
describe how multifidus attaches to vertebrae
runs superiorly 2-4 vertebrae above origin
describe how rotatores attaches to vertebrae
brevis goes from TP to SP IMMEDIATELY above. longus goes from TP to SP 2 vertebrae above. in the transverse plane
which muscle is spinalis capitis considered the deep fibres of
semispinalis capitis
where is multifidus most developped
lumbar spine
which layer 6 muscle has 3 subdivisions and what are they
multifidus. lumborum, thoracis, cervicis
where on the vertebrae does multifidus attach in each of its regions
- lumborum: mamillary processes
- thoracic: TPs
- cervicis: articular processes of C4-C7
what are the spinotransversales muscles
splenius capitis and splenius cervicis
what are the common actions of the spinotransversales muscles
extension of head and neck, lateral flexion, ipsilateral rotation
compare and contrast the actions of the erector spinae group
iliocostalis does the most actions (extension, ipsilateral lateral flexion/rotation). longissimus does the same but rotation is weaker. spinalis just does extension because it’s right in the middle on the spine
what is another name for the erector spinae group
sacrospinalis
describe the different subdivisions of spinalis (in terms of size/strength)
most developed in the thoracis region. infrequent or even absent in the cervicis region. indistinct in the capitis region (blends with semispinalis)
which of the semispinalis regions is most significant
semispinalis capitis. it is thick and powerful and the most developed compared to thoracis and cervicis
true/false multifidus attaches to atlas
false
which muscles make up the posterior abdominal wall
psoas major/minor, iliacus, QL, diaphragham
which muscles make up the anterior abdominal wall
lateral: external & internal obliques, transversus abdominus
medial: rectus abdominis and pyramidalis
describe the anterior abdominal wall
- no direct attachment to spine
- flex, laterally flex, rotate the trunk
- postural
- protect/compress viscera
- increase intraabdominal pressure (coughing, sneezing, elimination, support during lifting)
what is the name of the lateral (vertical) border of rectus abdominus
linea semilunaris
what is the name of the fibrous tissue that forms the medial border of rectus abdominus
linea alba
name the 3 fibrous bands within rectus abdominus (6 pack horizontal dividers) and describe where they sit
tendinous intersections. found in line with xiphoid process, umbilicus and halfway between the 2
Rectus sheath is an aponeurosis of
External and internal obliques and transversus abdomens
What marks the lower limit of the posterior Rectus sheath
Arcuate line
Which oblique does contralateral rotation
External. Both do ipsilateral lateral flexion.
Which muscle’s upper fibres blend with the diaphragm
Transversus abdominis
Between occiput, C1 and C2, these 2 muscles are absent - instead we have suboccipital muscles
Rotatores and multifidi
Why is the suboccipital triangle clinically relevant
Headaches and pain can occur. Vertebral artery and suboccipital nerve run through
Which 3 muscles form the sides of the suboccipital triangle
Obliquus capitis superior and inferior, Rectus capitis poster major
