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<v ->We're back with our healthy elite athlete.

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We've got an axial morphologic T1 type image on the left,

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and on the right, a more water weighted image.

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I wanna talk a little bit about rectus abdominis anatomy

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and the linea semilunaris.

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Now, this young, otherwise healthy individual,

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with good muscular development

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but he does have sports hernia,

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as you've seen in a prior vignette,

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has two equally sized rectus abdominis muscles

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left and right.

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Now, one thing radiologists often fail to do,

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is simply look at the size of the muscles,

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'cause muscular imbalance by itself

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may be a cause of sports hernia syndrome,

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and this is the one that is correctable

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with physical therapy.

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The tears, the delaminations,

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these do better with surgical intervention

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sooner rather than later,

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so they often end up in the surgical suite.

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The rectus abdominis consists

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of a medial and lateral bundle.

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This particular individual doesn't demarcate the bundles

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as well as some others that you'll see,

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and it's separated in the middle by the linea alba,

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creating the two individual bundles.

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The rectus abdominis has an origin

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from ribs five, six and seven,

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also from the xiphoid up higher,

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and the costoxiphoid ligaments.

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The rectus abdominis also has

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transverse striations called inscriptions,

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and the inscriptions are found up at the xiphoid,

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at the umbilicus and about midway in between.

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There's three on the right and three on the left,

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that's the term six pack,

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but some individuals will have five, two more below.

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So there's the potential to have a 10 pack.

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The rectus abdominis is also invested by aponeurosis.

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The aponeurosis is mostly formed by a split

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in the oblique internus muscle

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or the oblique internus aponeurosis,

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which separates, forms a layer on top,

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a layer in the bottom,

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and the bottom layer will fuse

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with the transverse abdominis muscle

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and the transversalis fascia.

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Now, along the lateral edge,

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perhaps seen a little better right here,

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is an area of coalescent hypointensity,

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right there at the interface between the inguinal ligament

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and the lateral margin of the rectus,

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and this is known as the linea semilunaris.

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It's somewhat curved shape right in this location.

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It's important because

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this is a not uncommon position for tears.

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When surgeons talk about "Defects that need to be repaired,"

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they're talking about micro tears,

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again, nothing is herniating through it,

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micro tears in this region

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that may need to be imbricated or sowed.

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These arise, the linea semilunaris,

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these fibers arise from the ninth rib

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and extend to the pubic tubercle.

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The lunaris is formed by the aponeurosis

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of the oblique internus muscle, the oblique externus muscle,

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and the transverse abdominis muscle,

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the rectus abdominis and the linea semilunaris

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both intimately involved with sports hernia syndrome.

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Dr. PL.