<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="00:00:09.612" end="00:00:12.755" style="s2">- Next we're going to examine<br />the infraspinatus tendon,</p>
<p begin="00:00:12.755" end="00:00:15.965" style="s2">as well as the glenohumeral<br />joint and labrum.</p>
<p begin="00:00:15.965" end="00:00:16.828" style="s2">We look at these together</p>
<p begin="00:00:16.828" end="00:00:19.011" style="s2">because they're in the same window.</p>
<p begin="00:00:19.011" end="00:00:21.627" style="s2">So what I like to do is<br />stand behind the patient,</p>
<p begin="00:00:21.627" end="00:00:26.507" style="s2">in this study, and use the<br />patient's scapular border</p>
<p begin="00:00:26.507" end="00:00:28.705" style="s2">as a landmark and follow their scapula</p>
<p begin="00:00:28.705" end="00:00:31.555" style="s2">across to the acromion that you'll feel.</p>
<p begin="00:00:31.555" end="00:00:34.660" style="s2">To allow the physician to<br />easily identify the structures,</p>
<p begin="00:00:34.660" end="00:00:36.775" style="s2">we recommend that you have the patient</p>
<p begin="00:00:36.775" end="00:00:37.919" style="s2">take their right hand,</p>
<p begin="00:00:37.919" end="00:00:39.384" style="s2">if we're examining the right shoulder,</p>
<p begin="00:00:39.384" end="00:00:42.823" style="s2">and reach across to the opposite shoulder.</p>
<p begin="00:00:42.823" end="00:00:46.199" style="s2">And I place the probe,<br />again facing medially</p>
<p begin="00:00:46.199" end="00:00:50.199" style="s2">towards the patient,<br />always maintaining contact.</p>
<p begin="00:00:52.264" end="00:00:53.895" style="s2">What we're able to do with ultrasound,</p>
<p begin="00:00:53.895" end="00:00:56.680" style="s2">if some of the images appear<br />a bit dark from shadowing</p>
<p begin="00:00:56.680" end="00:00:59.663" style="s2">we can adjust with a feature called gain.</p>
<p begin="00:00:59.663" end="00:01:03.024" style="s2">And there's a control on the<br />bottom of my ultrasound machine</p>
<p begin="00:01:03.024" end="00:01:05.775" style="s2">that will allow me to<br />brighten the lower aspect</p>
<p begin="00:01:05.775" end="00:01:07.791" style="s2">of the patient's shoulder.</p>
<p begin="00:01:07.791" end="00:01:10.199" style="s2">So I'm just going to<br />increase my depth here,</p>
<p begin="00:01:10.199" end="00:01:12.680" style="s2">next I'm visualizing the tendon fibers</p>
<p begin="00:01:12.680" end="00:01:16.688" style="s2">of the infraspinatus in a fibular pattern,</p>
<p begin="00:01:16.688" end="00:01:19.527" style="s2">looking for any abnormalities.</p>
<p begin="00:01:19.527" end="00:01:21.815" style="s2">Oftentimes if I'm suspecting a problem</p>
<p begin="00:01:21.815" end="00:01:23.575" style="s2">with the infraspinatus tendon,</p>
<p begin="00:01:23.575" end="00:01:27.064" style="s2">I'll request the patient to<br />externally rotate their arm.</p>
<p begin="00:01:27.064" end="00:01:30.320" style="s2">I'm going to have you slowly<br />push here, with your palm up.</p>
<p begin="00:01:30.320" end="00:01:33.653" style="s2">Just push your arm out, against my hand.</p>
<p begin="00:01:44.224" end="00:01:45.416" style="s2">So next we're gonna visualize</p>
<p begin="00:01:45.416" end="00:01:47.695" style="s2">the patient's glenohumeral joint,</p>
<p begin="00:01:47.695" end="00:01:49.847" style="s2">as well as their posterior labrum.</p>
<p begin="00:01:49.847" end="00:01:52.903" style="s2">In many patients we can<br />see their posterior labrum</p>
<p begin="00:01:52.903" end="00:01:55.432" style="s2">if they have a thin body habitus.</p>
<p begin="00:01:55.432" end="00:01:57.327" style="s2">And what we're looking for here</p>
<p begin="00:01:57.327" end="00:02:00.111" style="s2">is the posterior labrum that we can see,</p>
<p begin="00:02:00.111" end="00:02:01.671" style="s2">as a triangular pattern</p>
<p begin="00:02:01.671" end="00:02:05.007" style="s2">at the inferior aspect of the screen,</p>
<p begin="00:02:05.007" end="00:02:09.344" style="s2">as well as some cartilage<br />at the glenohumeral joint.</p>
<p begin="00:02:09.344" end="00:02:13.511" style="s2">This is the site of many<br />intra-articular injections.</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>