External abdominal muscle oblique (EO) is a flat superficial ab muscle situated on the lateral side, with anterior ab muscle develops anterolateral abdominal muscle wall. Its fibers directed inferiorly and medially, its fibers overlap through other abdominal muscle muscles; transverse abdominals, and internal obliques that assist support the abdominal wall surface and to decrease the danger of ab herniation.

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It originates indigenous the exterior surface that the lower eight ribs 5-12.



The many posterior yarn directed vertically and also other yarn anteromedially.

The EO proceeds as one aponeurosis at midclavicular line superior and also spinoumblical heat inferiority, whereby inserts right into the linea alba, the anterior fifty percent of iliac crest and the pubic tubercle.


The top two-third that external abdominal oblique offered by reduced intercostal nerves T7-T11 and also subcostal nerve T12.

The lower 3rd supplied by the iliohypogastricL1 from lumbar plexus.


Upper 2/3 obtain blood it is provided from branches of reduced posterior intercostal and subcostal arteries, lower 1/3 indigenous deep circumflex iliac artery.


Bilateral contraction of EO along with rectus abdominis and internal slope flexes the stems by illustration the pubis in the direction of the xiphoid.

Unilateral action: ipsilateral side flexion and also contralateral trunk rotation

External abdominal muscle oblique muscle v other abdominal muscle muscles helps to maintain abdominal muscle tension and support abdominal muscle viscera, rise intraabdominal press that is advantageous in forceful expiration, coughing, defecation.<1>

Clinical Relevance

Weakness that EO muscle v other abdominal muscle muscles boosts the hazard of hernia, umbilical hernia for example.<2>

Bilateral muscle weak decreases the ability of stems flexion, and you have the right to see anterior pelvic tilting from standing place in situations of bilateral weakness.

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Trigger points: abdominal muscle obliques may develop trigger points because of emotional stress, extra load during exercises, or even new exercise, because of incision, direct trauma, or second due to other visceral pathology. The most common sites for obliques cause points:

Lateral lower quadrant of the abdominal wall surface near come ASIS and also refer pain diagonally throughout the abdomen, groin and also genitalia.