Anterolateral abdominal wall Flashcards
Key functions of the abdominal wall
Forms a firm, flexible wall which keeps the abdominal viscera in the abdominal cavity.
Protects the abdominal viscera from injury.
Maintains the anatomical position of abdominal viscera against gravity.
Assists in forceful expiration by pushing the abdominal viscera upwards.
Involved in any action (coughing, vomiting) that increases intra-abdominal pressur
four main layers of teh anterolateral abdominal wall ex to int
; skin, superficial fascia, muscles and associated fascia, and parietal peritoneum
The superficial fascia consists of fatty connective tissue. The composition of this layer depends on its location. what is the composition above the umbilicus
a single sheet of connective tissue. It is continuous with the superficial fascia in other regions of the body.
The superficial fascia consists of fatty connective tissue. The composition of this layer depends on its location. what is the composition below the umbilicus
divided into two layers; the fatty superficial layer (Camper’s fascia) and the membranous deep layer (Scarpa’s fascia).
The superficial vessels and nerves run between these two layers of fascia.
The muscles of the anterolateral abdominal wall can be divided into two main groups. what are they
Flat muscles – three flat muscles, situated laterally on the abdominal wall on either side of the abdomen.stacked upon one and other
Vertical muscles – two vertical muscles, situated near the mid-line of the body.
the three flat muscles fibres run in differing directions and cross each other what does this do
strengthening the wall, and decreasing the risk of herniation.
In the anteromedial aspect of the abdominal wall, each flat muscle forms what
kepeping in mind that this thing covers the vertical rectus abdominis muscle
an aponeurosis
The aponeuroses of all the flat muscles become entwined in the midline, forming what
th linea alba
what is the linea alba
a fibrous structure that extends from the xiphoid process of the sternum to the pubic symphysis
what are the names of the flat muscldes
int. oblique
ext. obique
transversum abdominus
what is the external oblique and in which direction does its fibres run
The external oblique is the largest and most superficial flat muscle in the abdominal wall. Its fibres run inferomedially.
what are the attachments functions and innecvation of the eternal oblique
Attachments: Originates from ribs 5-12, and inserts into the iliac crest and pubic tubercle.
Functions: Contralateral rotation of the torso.
Innervation: Thoracoabdominal nerves (T7-T11) and subcostal nerve (T12).
what are the attachments functions and innecvation of the internal oblique
Attachments: Originates from the inguinal ligament, iliac crest and lumbodorsal fascia, and inserts into ribs 10-12.
Functions: Bilateral contraction compresses the abdomen, while unilateral contraction ipsilaterally rotates the torso.
Innervation: Thoracoabdominal nerves (T6-T11), subcostal nerve (T12) and branches of the lumbar plexus.
what is the internal oblique and in which direction does its fibres run
The internal oblique lies deep to the external oblique. It is smaller and thinner in structure, with its fibres running superomedially (perpendicular to the fibres of the external oblique).
what is the transversus abdomins and in which direction does its fibres run
The transversus abdominis is the deepest of the flat muscles, with transversely running fibres. Deep to this muscle is a well-formed layer of fascia, known as the transversalis fascia.
what are the attachments functions and innecvation of the itransversus abdominis
Attachments: Originates from the inguinal ligament, costal cartilages 7-12, the iliac crest and thoracolumbar fascia. Inserts into the conjoint tendon, xiphoid process, linea alba and the pubic crest.
Functions: Compression of abdominal contents.
Innervation: Thoracoabdominal nerves (T6-T11), subcostal nerve (T12) and branches of the lumbar plexus.
what are the two vertical muscles located in the midline of the anterolateral abdominal wall
rectus abdominis and pyrimidalus
what are the attachments functions and innecvation of the rectus abdominus
Attachments: Originates from the crest of the pubis, before inserting into the xiphoid process of the sternum and the costal cartilage of ribs 5-7.
Functions: As well as assisting the flat muscles in compressing the abdominal viscera, the rectus abdominis also stabilises the pelvis during walking, and depresses the ribs.
Innervation: Thoracoabdominal nerves (T7-T11).
what are the attachments functions and innecvation of the pyramidalis
Attachments: Originates from the pubic crest and pubic symphysis before inserting into the linea alba.
Functions: It acts to tense the linea alba.
Innervation: Subcostal nerve (T12).
what is the pyramialis structure and location
This is a small triangular muscle, found superficially to the rectus abdominis. It is located inferiorly, with its base on the pubis bone, and the apex of the triangle attached to the linea alba.
qhat is the rectus abdominus structure
long, paired muscle, found either side of the midline in the abdominal wall. It is split into two by the linea alba. The lateral border of the two muscles create a surface marking, known as the linea semilunaris.
, the muscle is intersected by fibrous strips,, what is the name of this and what does it do
tendinous intersections. The tendinous intersections and the linea alba give rise to the ‘six pack’ seen in individuals with a well-developed rectus abdominis.
what is the adominal marking of the rectus abdominus
he lateral border of this muscle is indicated by the linea semilunaris, a curved line running from the 9th rib to the pubic tubercle. The linea alba is a fibrous line that splits the rectus abdominis into two. It is visible as a vertical groove extending inferiorly from the xiphoid process.
where is the umbilus located
located midway between the xiphoid process and the pubis symphysis
what are the two horizonal planes of the abdomen
Transpyloric plane – Horizontal line halfway between the xiphoid process and the umbilicus, passing through the pylorus of the stomach.
Intertubercular plane – Horizontal line that joins the iliac crests.
what are the two vertical planes
run from the middle of the clavicle to the mid-inguinal point (halfway between the anterior superior iliac spine of the pelvis and the pubic symphysis). These planes are the mid-clavicular lines.
