<p begin="00:00:07.590" end="00:00:09.232" style="s2">- [Voiceover] A linear array transducer</p>
<p begin="00:00:09.232" end="00:00:11.400" style="s2">with a musculoskeletal exam type</p>
<p begin="00:00:11.400" end="00:00:13.944" style="s2">is used to perform an<br />ultrasound examination</p>
<p begin="00:00:13.944" end="00:00:16.266" style="s2">of the acromioclavicular joint.</p>
<p begin="00:00:16.266" end="00:00:18.252" style="s2">The patient is in a sitting position,</p>
<p begin="00:00:18.252" end="00:00:21.021" style="s2">with the hand resting<br />palm up on the thigh.</p>
<p begin="00:00:21.021" end="00:00:23.733" style="s2">The transducer is placed longitudinally</p>
<p begin="00:00:23.733" end="00:00:25.973" style="s2">over the acromioclavicular area,</p>
<p begin="00:00:25.973" end="00:00:29.385" style="s2">with the orientation marker<br />directed to the patient's right.</p>
<p begin="00:00:29.385" end="00:00:31.893" style="s2">The acromioclavicular<br />joint is seen between</p>
<p begin="00:00:31.893" end="00:00:34.142" style="s2">the bright, hyperechoic acromion,</p>
<p begin="00:00:34.142" end="00:00:36.498" style="s2">and the distal clavicle.</p>
<p begin="00:00:36.498" end="00:00:40.181" style="s2">The supraspinatous muscle<br />is lateral to the acromion.</p>
<p begin="00:00:40.181" end="00:00:42.884" style="s2">The acromioclavicular<br />joint should be scanned</p>
<p begin="00:00:42.884" end="00:00:45.338" style="s2">in an anterior to posterior direction</p>
<p begin="00:00:45.338" end="00:00:47.883" style="s2">to evaluate the entire joint area.</p>
<p begin="00:00:47.883" end="00:00:50.773" style="s2">The patient can move their<br />arm in a cross-chest fashion</p>
<p begin="00:00:50.773" end="00:00:53.799" style="s2">to further evaluate the<br />integrity of the joint.</p>
<p begin="00:00:53.799" end="00:00:56.268" style="s2">Movement of the acromioclavicular joint</p>
<p begin="00:00:56.268" end="00:00:59.351" style="s2">should be minimal with this maneuver.</p>

<p begin="00:00:07.408" end="00:00:09.080" style="s2">- [Voiceover] A linear array transducer</p>
<p begin="00:00:09.080" end="00:00:11.108" style="s2">with a musculoskeletal exam type</p>
<p begin="00:00:11.108" end="00:00:13.650" style="s2">is used to perform an<br />ultrasound examination</p>
<p begin="00:00:13.650" end="00:00:16.429" style="s2">of acromial impingement of the shoulder.</p>
<p begin="00:00:16.429" end="00:00:18.525" style="s2">The patient is in a sitting position</p>
<p begin="00:00:18.525" end="00:00:21.106" style="s2">with the patient's arm flexed 90 degrees,</p>
<p begin="00:00:21.106" end="00:00:23.311" style="s2">and the hand internally rotated.</p>
<p begin="00:00:23.311" end="00:00:25.636" style="s2">The transducer is placed transversely</p>
<p begin="00:00:25.636" end="00:00:27.911" style="s2">over the acromion and humeral head</p>
<p begin="00:00:27.911" end="00:00:31.310" style="s2">with the orientation marker<br />directed to the patient's right.</p>
<p begin="00:00:31.310" end="00:00:34.417" style="s2">The acromion and glenoid<br />tubercle of the humerus</p>
<p begin="00:00:34.417" end="00:00:38.100" style="s2">are seen as superficial,<br />bright, hyperechoic structures.</p>
<p begin="00:00:38.100" end="00:00:41.158" style="s2">The bird-beak shaped<br />supraspinatous and the bursa</p>
<p begin="00:00:41.158" end="00:00:43.667" style="s2">are just superior to the humerus.</p>
<p begin="00:00:43.667" end="00:00:46.494" style="s2">The patient is instructed<br />to slowly abduct the arm</p>
<p begin="00:00:46.494" end="00:00:47.973" style="s2">to evaluate the dynamic movement</p>
<p begin="00:00:47.973" end="00:00:50.305" style="s2">of the supraspinatous tendon and bursa</p>
<p begin="00:00:50.305" end="00:00:51.940" style="s2">under the acromion.</p>
<p begin="00:00:51.940" end="00:00:55.636" style="s2">The structures should pass<br />under the coracoacromial arch</p>
<p begin="00:00:55.636" end="00:00:58.217" style="s2">without the humerus<br />impacting the acromion,</p>
<p begin="00:00:58.217" end="00:01:01.186" style="s2">or without the subacromial<br />subdeltoid bursa</p>
<p begin="00:01:01.186" end="00:01:03.846" style="s2">bunching up with full abduction of the arm</p>
<p begin="00:01:03.846" end="00:01:06.513" style="s2">to exclude acromial impingement.</p>

<p begin="00:00:09.732" end="00:00:12.901" style="s2">- Next we're going to examine<br />the acromioclavicular joint,</p>
<p begin="00:00:12.901" end="00:00:15.431" style="s2">also known as the AC joint.</p>
<p begin="00:00:15.431" end="00:00:18.348" style="s2">Now this structure is<br />very easy to identify</p>
<p begin="00:00:18.348" end="00:00:20.456" style="s2">and I begin by just looking at the patient</p>
<p begin="00:00:20.456" end="00:00:22.798" style="s2">and identifying their bony acromion,</p>
<p begin="00:00:22.798" end="00:00:25.331" style="s2">which you can feel by palpation.</p>
<p begin="00:00:25.331" end="00:00:27.907" style="s2">Next, I'm going to place<br />the probe on the patient,</p>
<p begin="00:00:27.907" end="00:00:31.077" style="s2">again with the notch facing<br />medially towards the patient.</p>
<p begin="00:00:31.077" end="00:00:33.163" style="s2">Now with this structure,<br />it's obviously close</p>
<p begin="00:00:33.163" end="00:00:35.891" style="s2">to the surface, so we can<br />use a very short depth,</p>
<p begin="00:00:35.891" end="00:00:40.051" style="s2">and here we are, which<br />should be adequate at 2.7.</p>
<p begin="00:00:40.051" end="00:00:43.241" style="s2">So here we can visualize<br />the acromioclavicular joint</p>
<p begin="00:00:43.241" end="00:00:46.715" style="s2">and if we suspect pathology<br />with this in a patient,</p>
<p begin="00:00:46.715" end="00:00:49.467" style="s2">we can do a dynamic study<br />and have the patient</p>
<p begin="00:00:49.467" end="00:00:52.118" style="s2">strain his acromioclavicular joint and see</p>
<p begin="00:00:52.118" end="00:00:55.765" style="s2">if there's any separation<br />or ligamentous laxity.</p>
<p begin="00:00:55.765" end="00:00:58.422" style="s2">So what I do is I recommend<br />that the patient slowly takes</p>
<p begin="00:00:58.422" end="00:01:02.102" style="s2">his right arm and reaches it<br />across to his left shoulder</p>
<p begin="00:01:02.102" end="00:01:05.102" style="s2">while maintaining contact<br />over the AC joint.</p>
<p begin="00:01:05.102" end="00:01:08.685" style="s2">You can go ahead and<br />slowly move your left.</p>
<p begin="00:01:10.102" end="00:01:11.917" style="s2">Great, and back.</p>
<p begin="00:01:11.917" end="00:01:14.718" style="s2">And what we look for is if<br />there's an abnormal separation</p>
<p begin="00:01:14.718" end="00:01:18.551" style="s2">between the two acromion<br />and clavicular bones.</p>
<p begin="00:01:19.655" end="00:01:23.333" style="s2">In some cases of degeneration<br />and osteoarthritis,</p>
<p begin="00:01:23.333" end="00:01:26.345" style="s2">we'll see irregular bone<br />formations or even something</p>
<p begin="00:01:26.345" end="00:01:30.013" style="s2">known as the Geyser phenomenon,<br />which is bursal fluid</p>
<p begin="00:01:30.013" end="00:01:34.180" style="s2">extending out of the<br />acromioclavicular joint upwards.</p>