The main action for rectus abdominis is flexion of the trunk (flexion of thoracic and lumber spine), while it works by drawing symphysis and Sternum toward each other. Also, it works on posterior pelvic tilt with other abdominal muscles. Diastasis Recti Abdominis is a midline separation at the linea alba.
| Origin | Pubic symphysis, pubic crest |
|---|---|
| Insertion | Xiphoid process, costal cartilages of ribs 5-7 |
| Innervation | Intercostal nerves (T7-T11), subcostal nerve (T12) |
| Blood supply | Inferior epigastric and superior epigastric arteries; contributions from posterior intercostal, subcostal and deep circumflex arteries |
What is the action of the rectus abdominis?
The main function of the rectus abdominis is to move the body between the ribcage and the pelvis. external oblique muscles – these are on each side of the rectus abdominis. The external oblique muscles allow the trunk to twist, but to the opposite side of whichever external oblique is contracting.
What is the origin of rectus abdominis?
The rectus abdominis has two points of origin. The lateral head originates from the crest of the pubis, between the pubic symphysis and the pubic tubercle. The medial head originates from the pubic symphysis, interlacing with the fibres of the muscle on the contralateral side.
What is the origin insertion and action of the external oblique?
External abdominal oblique muscleOriginExternal surfaces of ribs 5-12InsertionLinea alba, pubic tubercle, anterior half of iliac crestActionBilateral contraction - Trunk flexion, compresses abdominal viscera, expiration Unilateral contraction - Trunk lateral flexion (ipsilateral), trunk rotation (contralateral)2 more rows
What is the origin insertion and action of the transversus abdominis?
Transverse abdominal muscleThe Transversus abdominis, Rectus abdominis, and Pyramidalis.DetailsOriginIliac crest, inguinal ligament, thoracolumbar fascia, and costal cartilages 7-12InsertionXiphoid process, linea alba, pubic crest and pecten pubis via conjoint tendon10 more rows
What is the rectus abdominis insertion?
Origin and insertion Inferiorly the rectus abdominis muscle is attached by two tendons; the larger one is attached to the pubic crest, from the pubic tubercle to the pectineal line, while the small, medial tendon is attached to the pubic symphysis.
What is the main action of the rectus abdominis muscle quizlet?
The rectus abdominis flexes the vertebral column in addition to compressing the abdominal wall. The other abdominal muscles compress the abdominal wall and laterally rotate the trunk.
What is the action of the rectus external oblique muscle?
Along with other abdominal wall muscles, the external oblique muscle flexes the trunk, assists expiration by depressing the ribs, and assists to maintain intra-abdominal pressure in evacuation of luminal contents and supports intra-abdominal viscera.
Which is a part of the origin of the transverse abdominis?
The transversus abdominis has several origin points: Lateral one-third of the superior surface of the inguinal ligament and the associated iliac fascia. Anterior two-thirds of the inner lip of iliac crest. Thoracolumbar fascia between the iliac crest and the 12th rib.
Where are the rectus abdominis located?
abdomenRectus abdominis: This pair of muscles goes down the middle of your abdomen from your ribs to the front of your pelvis. The muscles hold your internal organs in place and keep your body stable during movement.
Where does the transverse abdominis muscle insertion?
It attaches at one end (considered the “origin” by some) at the inguinal ligament, the iliac crest, the thoracolumbar aponeurosis and the internal surface of the costal cartilages 7-12.
What is the function of the transverse abdominis quizlet?
Transversus abdominis is the deepest of the abdominal muscles, it is an important core muscle and its primary function is to stabilise the lumbar spine and pelvis before movement of the lower and /or upper limbs occur.
What is the origin and insertion of the internal oblique muscle?
Posterior fibers: originate from the posterior end of the iliac crest and the thoracolumbar fascia. The fibers then ascend superolaterally and insert into the inferior borders and tips of the lower three or four ribs and their cartilages.
What is the origin of the 4 Recti muscles?
The four recti muscles all arise from a connective tissue ring called the common tendinous ring (annulus of Zin). This is located at the apex of orbit, surrounding the optic canal. Respectively, the recti muscles insert onto the superior, inferior, medial and lateral sides of the eyeball.
What is the origin and insertion of the rectus femoris?
The rectus femoris is a fusiform muscle that consists of two heads. It originates from two sites on the ilium; the anterior inferior iliac spine (straight head) and supraacetabular groove (reflected head)....Origin and insertion.OriginAnterior inferior iliac spine, supraacetauluar grooveInnervationFemoral nerve (L2-L4)3 more rows
What is a point of origin of the rectus femoris muscle?
Origin: Straight head from anterior inferior iliac spine; reflected head from groove just above acetabulum. Insertion: Base of patella to form the more central portion of the quadriceps femoris tendon. Action: Extends the knee.
What is the origin of the rectus abdominis muscle in the trunk musculature?
Rectus abdominis The muscle originates from the pubic crest and pubic symphysis. It inserts onto the xiphoid process of the sternum and costal cartilages of the 5th to 7th ribs. Rectus abdominis acts as a flexor of the trunk and an accessory muscle of expiration.
Where is the rectus abdominis muscle located?
The rectus abdominis muscle inserts onto the costal cartilage of the fifth through seventh ribs. The costal cartilage is shown in this picture as the gray extensions at the front ends of the ribs.
What causes the rib cage and pelvis to tilt inward towards the abdomen?
The rectus abdominis causes the rib cage and pelvis to tilt inward towards the abdomen. Think about those late night infomercials and the movements of the people who use these workout machines.
How many ribs are there on each side of the rib cage?
There are 12 total ribs on each side of the rib cage, and the rectus abdominis inserts onto the fifth through seventh ribs. Xiphoid process. The xiphoid process is a small piece of cartilage that extends off the bottom part of the sternum (breastplate).
What is the name of the ab machine?
So next time you're watching TV late at night and see an infomercial for an ab machine, be sure to remember that the true name of the abs is rectus abdominis.
Which muscle has multiple insertion points?
The rectus abdominis muscle also has multiple locations of insertion. The following charts describes these points of insertion. Point of Insertion. Description. Costal cartilage of the fifth through seventh ribs. The costal cartilage are sections of connective tissues that extend from the front ends of the ribs.
Where is the pubic crest located?
The pubic crest is located at the front, middle of the pelvic bone. The pubic symphysis is the cartilage that makes up the mid-line of the front of the pelvic bone. The rectus abdominis originates from the pubic crest and the pubic symphysis, both of which are located at the front, middle of the pelvic bone.
Which bone tilts the rib cage and pelvic bone towards the middle of the abdomen?
The rectus abdominis tilts the rib cage and pelvic bone towards the middle of the abdomen, such as when a person is performing an abdominal crunch.
How many segments does the rectus abdominis have?
Each rectus abdominis muscle is split into three distinct segments by three transverse fibrous intersections, one at the umbilicus, one at the level of the xiphoid process and one halfway between the two.
What is the origin of the rectus abdominis?
Rectus Abdominis: Origin, Insertion, Action & Nerve Supply. Rectus Abdominis Muscle: The rectus abdominis muscle is a long strap muscle that continues the entire length of the anterior abdominal wall. It is broader above and lies close to the midline, being separated from its associated by the linea alba. It arises by two heads from the anterior ...
Which nerves are involved in flexion of the lumbar spine?
The lower six thoracic nerves. Function of the Rectus Abdominis. The rectus abdominis muscle is an essential postural muscle. Besides a fixed pelvis, contraction results in flexion of the lumbar spine. While the ribcage is fixed contraction effects in a posterior pelvic tilt.
Which muscle is inserted between the aponeuroses of the external and internal obliques and trans?
The rectus abdominis muscle is inserted between the aponeuroses of the external and internal obliques and transversus abdominis muscles that form the rectus sheath.
What arteries do the transversus abdominis muscle have?
Blood supply. The transversus abdominis muscle receives its arterial blood supply from the following arteries: Lower posterior intercostal arteries, arising from the descending thoracic aorta. Subcostal arteries, given off by the descending thoracic aorta. Superior epigastric artery, given off by the internal thoracic artery.
What is the transversalis fascia?
Approximately 1.5 cm above the midpoint of the inguinal ligament, the transversalis fascia, contains a round opening called the deep inguinal ring. Along the medial border of the deep inguinal ring, the free lower border of transversus abdominis occasionally gives off a band of fibers called the interfoveolar ligament.
What muscles make up the anterolateral abdominal wall?
Combined with the two anterior abdominal muscles ( rectus abdominis and pyramidalis ), these muscles make up the anterolateral abdominal wall. As its name suggests, the fibers of transversus abdominis are oriented transversely, ...
Why is the transversus abdominis important?
Together with the other abdominal muscles, transversus abdominis is important for maintaining normal abdominal tension and increasing intra-abdominal pressure.
What muscles cause pressure to increase?
The lateral abdominal muscles, including transversus abdominis, also cause compression of the intra-abdominal viscera thereby increasing the intra-abdominal pressure. This action is facilitating expulsive functions such as forced expiration, micturition, defecation and final stages of childbirth.
Where is the thoracolumbar fascia?
Thoracolumbar fascia between the iliac crest and the 12th rib. Internal aspects of the lower six ribs and their costal cartilages. From their origin points, the transversus abdominis fibers course horizontally over the lateral abdominal wall towards the midline, oriented perpendicular to the linea alba.
Which muscle is involved in the transversus abdominis?
The aponeurosis of the transversus abdominis muscle participates in comprising the rectus sheath. This is a multilayered aponeurosis that encloses the biggest portion of the rectus abdominis and pyramidalis muscles on their anterior and posterior sides.
