Muscles of the trunk Back muscles Thoracic wall Diaphragm

Muscles of the trunk Back muscles Thoracic wall Diaphragm

Muscles of the trunk
 Back muscles
 Thoracic wall
 Diaphragm
Muscle: Trunk 1
Back muscles on vertebral column
 1) Erector spinae (Sacrospinalis)
a) Iliocostalis (lateral)
b) Longissimus
c) Spinalis (medial)
 2) Transversospinalis
a) Semispinalis
b) Multifidus
c) Rotatores
 Innervation: dorsal rami of spinal nerve
Muscle: Trunk 2
Iliocostalis
Iliocostalis (Sacrospinalis): aponeurotic origin
Iliocostalis cervics: angles of ribs 3-6 to C4-
6 trans. proc.
Iliocostalis thoracis: angles of ribs 7-12 to
angles of ribs 1-6 and C7 trans. proc.
Iliocostalis lumborum: sacrum, L and T12
spin. proc. , ligaments, iliac crest to angles of
7-12 ribs
Muscle: Trunk 3
Ilocostalis
Aponeurotic origin: Iliac
crest, Post. Sup. Iliac
spine
Cervics: C4-6 trans. proc.
Thoracis: ribs 1-6
Lumborum: ribs 7-12
Muscle: Trunk 4
Longissimus
Aponeurotic origin in iliac
crest
Thoracics: ribs
Cervics: rib, trans. proc.
Capitis: mastoid proc.
Muscle: Trunk 5
Spinalis
Common origin in
sacroiliac joint, and
spinous proc.
Spinous proc. of T,
C- spine, and
nuchal lig.
Muscle: Trunk 6
Transversospinalis group of back muscles
a) Semispinalis: 5 segments: capi., cerv., thor.
b) Multifidus: 3 segments: cerv., thor., lumb.,
sacral
c) Rotatores: adjacent segments
Muscle: Trunk 7
Semispinalis
Origin: C4-T12 (trans.
proc.)
Trans. Proc Insertion: occipital bone,
spinous proc.
Span 5 (4-6) spines
Muscle: Trunk 8
Multifidus
Origin: post. Sacrum
Insertion: spinsou proc.
3 (2-4) segments above
Muscle: Trunk 9
Rotatores
Origin: trans. proc. (esp. at T)
Insertion: trans. proc. or
spinous proc.; spanning 2
spines (long) or 1 spine (short)
Muscle: Trunk 10
betw’ spin. & trans. proc
trans. proc.
rib
paraspinal muscles Muscle: Trunk 11
Paraspinal muscles
 = paravertebral muscles
 Innervated by dorsal rami of spinal nerves
Muscle: Trunk 12
Muscles of thoracic wall
 1) Intercostals: between adjacent ribs
a) External intercostal mm.
b) Internal intercostal mm.
c) Innermost intercostal mm.
 [ 2) Subcostals]
 [ 3) Transversus thoracis]
 [ 4) Small mm. between ribs and vertebrae]
Muscle: Trunk 13
Muscle: Trunk 14
Muscle: Trunk 15
Muscle: Trunk 16
Diaphragm
 Origin: deep xiphistemum, costal margin, lat. and med.
arcuate lig., upper lumbar vertebrae
  central tendon; 3-lobed, central lobe more
anteriorly positioned
 ventral rami of C3-5; phrenic n.
 Major apertures in the diaphragm:
 a) esophageal opening: in right crus; transmits
vagus n., br. of left gastric a.
 b) vena caval opening: pierces the tendinous part
 c) aortic opening; behind median arcuate lig.,
between right and left crura, also for thoracic duct
Muscle: Trunk 17
Muscle: Trunk 18
Muscle: Trunk 19
Review on Muscles for respiration
 Inspiration
Diaphragm
External Intercostal muscles
 Expiration
Internal intercostal muscles
Muscle: Trunk 20