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Alright, so we're, uh, we're continuing on our discussion

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of the rotator cuff and, uh, we're gonna summarize the major

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components of the cuff, of which there are actually six.

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And we're gonna point each one of these out to you.

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We've got the supraspinatus, the infraspinatus,

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the teres minor, the biceps and its long head, the

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coraco humeral ligament, and the capsule itself.

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So those are the six.

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So when you look at the rotator cuff, you're gonna,

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you're gonna work your way right down that checklist.

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So here we have a sagittal drawing of a shoulder.

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This would be anterior.

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This would be posterior.

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So here's the supraspinatus.

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Here's the infraspinatus.

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And this little slit in between is

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known as the posterior interval.

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And then on the next cut, headed from

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lateral to medial, here's the supraspinatus.

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There's the infraspinatus.

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This little slit, this fibroelastic membrane slit, It's the

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interface between the two, and that's the subscapularis,

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and between the subscapularis and the supraspinatus

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will be the anterior interval, which means there also

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has to be a far posterior interval, so some people call

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this the posterior, middle, and anterior intervals.

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But on this cut we have subscapularis, supraspinatus,

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infraspinatus, and if you're very familiar with the

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anatomy, you may note that the biceps is slipping

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down from the intra to the extra-articular space.

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We're going to show it to you a lot

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better when we move on to our actual case.

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So now let's go a little bit more

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medial to the level of the glenoid.

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And there is the coracohumeral ligament.

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This is known as the extra-articular

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portion of the coracohumeral ligament.

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Which contributes the deepest fibers of

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the rotator cuff blending with the capsule.

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Now we're coronal and we're in the back.

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So, since we're in the back, you're

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seeing infraspinatus and teres.

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I also, when I'm looking at the rotator

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cuff, look at the trapezius to see if

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there is weakness of the shrug mechanism.

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And I look at the deltoid to see

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if there is weakness of abduction.

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Usually, patients that aren't picking up their

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arm have a lot of atrophy and fatty replacements.

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Then we move forward.

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We get the back portion of the supraspinatus and its tendon.

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We move forward even more.

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We have the anterior portion of the

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supraspinatus and the subscapularis.

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So then we go to the axial projection.

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We're up high.

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We see the supraspinatus and its

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fibers arcing back a little bit.

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And we have the infraspinatus

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fibers arcing forward a little bit.

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We come down a little more.

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It's hard for me to control.

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There's a little bit of the biceps being volume average.

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We'll focus on that in our cases.

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There's the coracohumeral ligament, which forms

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the anterior boundary of the rotator interval and

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contributes the deepest fibers of the rotator cuff.

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Here's the inps in the back, and then finally

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as we get down low or lower, we see the

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subscapularis very nicely with its tendon.

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That's very broad and the infraspinatus coming

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in from the back, mostly muscular in this position.

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So again, six components of the cuff.

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This is just a very cursory look at them anatomically.

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Supraspinatus.

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Infraspinatus.

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Teres minor.

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Biceps and its long head.

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Labral anchor complex.

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Coracohumeral ligament and capsule.

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Those are the six on your rotator cuff checklist.