Muscles of Trunk Flashcards
THE BREAST - BLOOD SUPPLY
LATERALLY:
- Thoraco-acromial
- Lateral thoracic
- Subscapular arteries
MEDIALLY:
- Internal thoracic artery branches
- 2nd to 4th Intercostal arteries via branches
THE BREAST - VENOUS DRAINAGE
Axillary
Internal thoracic
Intercostal veins
THE BREAST - INNERVATION
Anterior and Lateral Branches Intercostal Nerves T4-T6
Superiorly by Cutaneous Branches of Cervical Plexus C1-C4
THE BREAST - LYMPHATIC DRAINAGE
75% Axillary Nodes
25% Parasternal Nodes
EXTERNAL INTERCOSTAL (Origin)
Inferomedially…
INSPIRATION!!
Inferior margin ribs
EXTERNAL INTERCOSTAL (Insertion)
INSPIRATION!!
Superior margin ribs below
EXTERNAL INTERCOSTAL (Action)
INSPIRATION!!
Elevate ribs during forced inspiration
EXTERNAL INTERCOSTAL (Innervation)
INSPIRATION!!
Anterior Rami T1- T11
INTERNAL INTERCOSTAL (Origin)
Superomedially…
EXPIRATION!!
Superior margin ribs below
INTERNAL INTERCOSTAL (Insertion)
EXPIRATION!!
Inferior lateral edge of costal groove above
INTERNAL INTERCOSTAL (Action)
EXPIRATION!!
Depresses ribs during forced expiration
INTERNAL INTERCOSTAL (Innervation)
EXPIRATION!!
Anterior Rami T1- T11
INNERMOST INTERCOSTAL (Origin)
Superomedially…
Deep surface ribs below
INNERMOST INTERCOSTAL (Insertion)
Medial edge costal grooves
INNERMOST INTERCOSTAL (Action)
Depress ribs during forced expiration
INNERMOST INTERCOSTAL (Innervation)
Anterior Rami T1-T11
SUBCOSTALES
Internal surface of 1 rib to internal surface of 3 ribs below
Acts to depress ribs
TRANSVERSUS THORACIS (Origin)
Posterior aspect Xiphoid Process
Inferior aspect Sternum
Adjacent costal cartilages lower true ribs
TRANSVERSUS THORACIS (Insertion)
Lower border Costal Cartilages Rib 3-6
TRANSVERSUS THORACIS (Action)
Depresses costal cartilages
TRANSVERSUS THORACIS (Innervation)
Anterior Rami T1-T11
DIAPHRAGM - PERIPHERAL ORIGIN POINTS
Separates Thoracic cavity from Abdominal cavity
- Xiphoid Process of Sternum
- Costal Margin
- Ribs 11 and 12
- Ligaments across Posterior Abdominal Wall
- Vertebrae of Lumbar Region
Fibres converge to join Central Tendon
DIAPHRAGM -CRURA
Right Crus: L1-L3
Left Crus: L1-L2
~Crura Connected by tendinous arch = Median Arcuate Ligament
~L1/L2 and Transverse Process L1, Lateral to crura= Medial Arcuate Ligament
~L1 and Rib 12, covers Quadratus Lumborum = Lateral Arcuate Ligament
DIAPHRAGM - STRUCTURES PASSING THROUGH
AORTIC HIATUS - LEVEL T12
- Thoracic duct
- Azygos vein
- Median arcuate ligament
OESOPHAGEAL HIATUS - LEVEL T10
- Anterior/ Posterior vagal trunks
CAVAL OPENING - LEVEL T8
- Inferior Vena Cava
- Right Phrenic Nerve
DIAPHRAGM - DOMES
Dome appearance left and right side
Left dome= 5th intercostal space
Right dome= Rib 5
DIAPHRAGM - BLOOD SUPPLY
SUPERIOR surface:
~ Pericardiophrenic
~ Musculophrenic
~ Superior phrenic
INFERIOR surface:
~ Inferior phrenic
DIAPHRAGM - INNERVATION
Phrenic Nerve C3,C4, C5
(C3,4,5 keeps the Diaphragm alive)
PSOAS MAJOR (Origin)
Body, Intervertebral Discs and Transverse Processes T12, L1- L5
PSOAS MAJOR (Insertion)
Lesser trochanter Femur
PSOAS MAJOR (Action)
Flex thigh at hip joint when trunk stabilized
Flex trunk when body supine
PSOAS MAJOR (Innervation)
Anterior Rami L1-L3
PSOAS MINOR (Origin)
Body T12 and L1
PSOAS MINOR (Insertion)
Pectineal line and Illiopubic eminence
PSOAS MINOR (Action)
Weak flexor Lumbar vertebral column
PSOAS MINOR (Innervation)
Anterior Rami L1
QUADRATUS LUMBORUMS (Origin)
Psoas Major Medially and Transversus Abdominus Laterally
- Transverse Process L5
- Iliac Crest
- lliolumbar Process
QUADRATUS LUMBORUMS (Insertion)
Transverse Processes L1- L4
Inferior border Rib 12
QUADRATUS LUMBORUMS (Action)
Depresses and Stabilizes Rib 12
Lateral bending of trunk
Both muscles together extend trunk
QUADRATUS LUMBORUMS (Innervation)
Anterior Rami T12, L1-L4
ILIACUS (Origin)
Psoas Major Medially and Transversus Abdominus Laterally
- Iliac fossa
ILIACUS (Insertion)
Joins Psoas Major insert on Iesser trochanter Femur
ILIACUS (Action)
Flexes thigh at hip joint
Flexes trunk when supine
ILIACUS (Innervation)
Femoral Nerve
SUPERFICIAL FASCIA
- SUPERFICIAL layer - Campers Fascia
~ continues over inguinal ligament
~ over penis as Dartos fascia in scrotum
~ retain fat in labia majora
2.DEEP layer - Scarpa’s Fascia
~ little to no fat
~ continues into thigh
~ below inguinal ligament fuses with fascia lata
EXTERNAL OBLIQUE (Origin)
Midline aponeurosis = LINEA ALBA
Fibers run inferomedially
- Lower six rib shafts (T7-T12)
EXTERNAL OBLIQUE (Insertion)
Linea Alba
Pubic Tubercle
EXTERNAL OBLIQUE (Action)
Flexion of torso
EXTERNAL OBLIQUE (Innervation)
Thoracoabdominal Nerves (Anterior Rami T7-T11)
INTERNAL OBLIQUE (Origin)
Fibres run superomedially
- Inguinal ligament
- Iliac Crest
INTERNAL OBLIQUE (Insertion)
Linea Alba
Ribs 10-12
INTERNAL OBLIQUE (Action)
Flexion of trunk
INTERNAL OBLIQUE (Innervation)
Thoracoabdominal Nerves (Anterior Rami T7-T11)
Subcostal Nerve
TRANSVERSALIS ABDOMINUS (Origin)
TRANSVERSALIS FASCIA deep to muscle - attaches to THORACOLUMBAR FASCIA
Thoracolumbar fascia
Iliac Crest
Inguinal ligament
Costal cartilages lower 6 ribs
TRANSVERSALIS ABDOMINUS (Insertion)
Linea Alba
Pubic Crest
Pectineal line
TRANSVERSALIS ABDOMINUS (Action)
Compresses abdominal contents
TRANSVERSALIS ABDOMINUS (Innervation)
Thoracoabdominal Nerve (Anterior Rami T7-T11)
Subcostal Nerve
RECTUS ABDOMINUS (Origin)
3-4 transverse fibrous bands = TENDINOUS INTERSECTIONS
- Pubic Crest
- Pubic Symphysis
RECTUS ABDOMINUS (Insertion)
Costal Cartilages Rib 5-7
Xiphoid Process
RECTUS ABDOMINUS (Action)
Compresses abdominal contents
Flexes vertebral column
Tenses abdominal wall
RECTUS ABDOMINUS (Innervation)
Thoracoabdominal Nerves (Anterior Rami T7-T11)
Subcostal Nerve
PYRAMIDALIS (Origin)
Pubis symphysis
Pubic symphysis
PYRAMIDALIS (Insertion)
Linea Alba
PYRAMIDALIS (Action)
Tenses Linea Alba
PYRAMIDALIS (Innervation)
Subcostal Nerve
RECTUS SHEATH
Aponeurotic layer encloses rectus abdominus
ANTERIOR WALL: Aponeurosis external oblique and internal oblique
POSTERIOR WALL: Aponeurosis internal oblique and transversus abdominus
DERMATOMES
Area of skin supplied by single nerve or spinal card level
Nipple = T4
Umbilicus = T10