Muscles of the trunk Flashcards
The series of ducts and secretory lobes converge to form which ducts?
About 15-20 lactiferous ducts which opens directly onto the nipple
Name a circular pigmented area around the nipple.
Areola
The connective tissue surrounding the ducts and lobules when condensed they form———— which continuous with ———-and support the breast
Connective tissue surrounding ducts and lobules condense to form suspensory ligaments of breast [Coopers ligaments] which are continuous with dermis and supports the breast.
Fats are predominant in ———-female?
non-lactating female
Name the space separating the base of the breast and the pectoralis major
Retromammary space
In which position does the base of the lies in?
Rib 2 to rib 6
Describe blood supply of the breast.
Laterally: Thoraco-acromial, Lateral thoracic and Subscapular arteries.
Medially: Internal thoracic artery branches.
2nd – 4th Intercostal arteries via branches.
Venous Drainage structures of the breast
Axillary, Internal thoracic and Intercostal veins.
The innervation of the breast
Anterior and Lateral Branches of C2-C4.
the lymphatic drainage
About 75% drains to axillary nodes, rest is usually parasternal nodes.
.»Breast in males consist of small ducts.
The function of Intercostal muscle
They provide structural support for intercostal space and can move the ribs.
The direction of the External intercostal Muscles fibers and its pairs
Have 11 pairs.
fibers pass inferior medially.
The origin, insertion of the external intercostal muscle
Origin: inferior margin of the superior ribs
insertion: superior margin of the ribs below
The innervation and action of the external intercoastal muscles
Anterior rami of T1-T11
The muscles work by elevating the rib cage during forced inspiration.
The direction of The internal intercostal muscles fibers and its pairs
11 pairs
fibers run superior medially.
its is intermediate to external and the inner most intercostal muscle
The origin and Action of the internal Intercostal muscle
originate: from the superior margin of the ribs below.
insert: inferior lateral edge of costal groove above.
The innervation and action of internal intercostal
action: depresses the ribs during forced expiration.
innervation: same innervation as the external (anterior rami T1-T11)
The direction of The inner most intercostal muscle fibers and pairs
It has 11 pairs.
the fiber runs superior medially.
The origin and insertion of innermost intercoastal muscle
Origin: Deep surface of ribs below.
Insertion: Medial edge of costal grooves
Innervation and action of innermost intercostal muscle
innervation: anterior rami of T1 and T11
action: to depress the ribs during inspiration.
What is the most evident in lateral thoracic wall?
Neurovascular bundle runs between innermost and internal intercostal muscles.
The origin of subcostal muscles
Run from the internal surface of one rib to the internal surface of another rib bridging several intercostal spaces.
Same plane as innermost intercostal muscles
Span several ribs, more numerous in lower regions of posterior thoracic wall.
what action is provided by the subcostal muscles in relation to ribs?
Acts to depress ribs.
Describe the Transversus thoracis muscles
found in same plane as the innermost costal muscles
found in deep surface of the anterior thoracic wall
The origin and insertion of the transversus muscles
origin: Posterior aspect of xiphoid process and inferior aspect of sternum and adjacent costal cartilages of lower ribs
insertion: lower border of costal cartilages of rib 3-6
Innervation and action of transversus thoracic muscle
by the anterior rami of T1-T11
depresses the costal cartilages during a forced respiration.
What is a Diaphragm?
A diaphragm is thin musculature structure that fills inferior thoracic aperture separating the thoracic and abdominal cavities..
Name the peripheral original points of the diaphragm.
Xiphoid process of the sternum
costal margin
rib11 and 12
ligaments running across structures of posterior abdominal wall.
vertebrae of lumbar region.
Describe the fibers.
runs from the peripheral origin points converging to joint central tendon
The structure that anchors the diaphragm to the lumber vertebrae
crura
Right crus: attached to L1-L3
Left crus: attached to L1-L2
The crura are connected across the midline by a tendinous arch …………
Median arcuate ligament
The attachment of medial arcuate ligament
attachment to L1-2 and transverse of L1
lies lateral to crura and covers the psoas major
The attachment of the lateral arcuate ligament.
attached to rib 12 and L1.
covers Quadratus lumborum.
name the structures the structures passing through the diaphragm..
Aortic hiatus: aorta lies the anterior to the vertebral bodies at T12 and posterior to the median arcuate ligament.
oesophageal hiatus: Oesophagus passes through right crus at T10 just left of the aortic hiatus.
Caval opening: Inferior Vena Cava passes through tendinous part at T10.
what goes through the oartic hiatus?
Descending Aorta, Thoracic Duct and Azygos Vein also pass through here.
Level T12
What goes the oesophageal hiatus ?
oesophagus, Anterior and Posterior Vagal Trunks also pass through here.
level T10
what possess through caval opening and at what level?
inferior vena cava- level T10
right phrenic nerve
level T8
The content of the diaphragm (Domes)
Classic dome appearance on right and left side is due to abdominal contents that pushes the lateral parts upward and the pericardial sac that pushes the central tendon downwards.
During the normal expiration the Domes ……….
On left dome lies at the level of the 5th intercostal space
Right dome at rib 5.
blood supply and innervation of the diaphragm?
Superior surface – Pericardiophrenic, Musculophrenic and superior phrenic arteries.
Inferior surface – Inferior phrenic artery.
innervation: phrenic nerve of C3, C4,C5.
The origin and insertion the Psoas major
the psoas major lies posterior medially to the psoas minor.
covers the anterior lateral surface of lumbar vertebrae
origin: Body, Intervertebral discs and Transverse processes of T12, L1-L5.
insertion: lesser trochanter of femur
The innervation and action the psoas major
anterior rami of L1-L3
flexes the thigh at hip joint- powerful flexors
flexes the trunk when the body is supine
origin and insertion of psoas minor
Lies on psoas major.
Slender muscle with long tendon.
Origin: Body of T12 and L1.
Insertion: Pectineal line and Iliopubic eminence.
the innervation and action the psoas minor
anterior rami of L1
weak flexor of lumbar vertebral column
describe the qruadratus lumborum
Fills space between Rib 12 and Iliac Crest.
Overlapped by Psoas major medially and Transversus abdominus laterally.
The origin and insertion of tyhe quadratus lumborum
Origin: Transverse process of L5, Iliac Crest, Iliolumbar process.
Insertion: Transverse processes of L1-L4, Inferior border of rib 12.
The action and innervation of quadratus lumborum
Depresses and stabilizes Rib 12, lateral bending of trunk, both muscles together extend trunk.
anterior rami T12, L1-L4
the origin and insertion the iliacus
Blends with psoas major which is sometimes collectively referred to as iliopsoas muscle.
Origin: Iliac fossa.
Insertion: Joins with Psoas major to insert on lesser trochanter of Femur.
the origin and insertion the iliacus
Blends with psoas major which is sometimes collectively referred to as iliopsoas muscle.
Origin: Iliac fossa.
Insertion: Joins with Psoas major to insert on lesser trochanter of Femur.
what is the innervation of the iliacus
Innervation: Femoral nerve.
Action: Flexes thigh at hip joint and flexes trunk when supine
what is a fascia?
a single layer of fatty connective tissue that forms two layers below the umbilicus..
Types of fascia.
superficial layer- campers fascia
continuous over inguinal ligament continuous over penis as dartos fascia in scrotum. in female retains fat in labia
deep layer- scarpers facsia
thin membranous, little to no fat
continues over the thigh just below the inguinal ligament it fuses with fascia lata
Describe the external oblique abdominus
Most superficial anterolateral flat muscle, laterally placed muscle, fibres run inferomedially.
Large aponeurotic component that covers anterior part of abdominal wall.
At midline the aponeurosis forms the linea alba which runs from xiphoid process to pubic symphysis.
The origin and insertion of the External obliquus abdominus
Origin: Lower six rib shafts (T7-T12).
insert on the Linea alba and pubic tubercle.
the innervation and action of external oblique muscle
innervation: thoracoabdominal nerve (T7-T11) anterior rami
action: flex torso
which ligament are associated with the external oblique muscle?
Inguinal Ligament
Formed at lower border of external oblique aponeuroses.
Passes between anterior superior iliac spine and pubic tubercle.
Folds under itself forming a trough that helps form inguinal canal.
Fibres of medial end of the ligament form:
Lacunar ligament – between inguinal ligament and pecten pubis
Pectineal ligament – from lacunar ligament to pecten pubis.
The origin and innervation of internal oblique dominus.
Laterally placed muscle, fibers run superomedial.
Smaller and thinner muscle.
Origin: Inguinal ligament, iliac crest.
Insertion: Linea alba, Ribs 10-12.
The action and innervation of the internal oblique muscle.
: Thoracoabdominal nerves (T7-T11 anterior rami) and Subcostal nerve.
Action: Flexion of trunk.
the ORIGIN and the insertion of the transversalis abdominus
Origin: Thoracolumbar fascia, iliac crest, inguinal ligament and costal cartilages of lower 6 ribs.
Insertion: Linea alba, Pubic crest, Pectineal line.
the innervation and action the transversal abdominus muscle.
Innervation: Thoracoabdominal nerves (T7-T11 anterior rami) and Subcostal nerve.
Action: Compresses abdominal contents.
transversalis fascia
deep to this muscle (transversalis abdominus)
lines the abdominal cavity and crosses into the pelvic cavity.
communicates with the fascia on either side of the abdomen, fascia inferior to diaphragm and fascia of the posterior wall.
Transversalis fascia also attaches onto the thoracolumbar fascia.
describe the rectus abdominus muscle.
Long, flat muscle extending length of anterior abdominal wall.
Intersected by 3-4 transverse fibrous bands – Tendinous intersections.
The origin, insertion of rectus abdominus
Origin: Pubic crest and Pubic symphysis.
Insertion: Costal cartilages of Rib 5-7, and xiphoid process.
The innervation and action of the rectus abdominus
Innervation: Thoracoabdominal nerves (T7-T11 anterior rami) and Subcostal nerve.
Action: Compresses abdominal contents, flexes vertebral column and tenses abdominal wall.
the action and insertion of the pyramidalis muscle
Small, triangular muscle, sometimes absent.
Anterior to rectus abdominus, base lies on pubis and apex is attached to linea alba.
Origin: Pubis and Pubic symphysis.
Insertion: Linea alba.
the innervation and action of the pyramidalis
Innervation: Subcostal nerve.
Action: Tenses linea alba.
what is Rectus sheath
is an aponeurotic layer that encloses the abdominus.
formed by the aponeurosis of external oblique, internal oblique and transversalis abdominus.
The wall of the abdomen:
Anterior Wall: Aponeurosis of external oblique and internal oblique.
Posterior Wall: Aponeurosis of internal oblique and transversus abdominus.
Lower one-quarter of rectus sheath – no posterior wall, muscle in direct contact with transversalis fascia.
