Two-thirds of people will have shoulder pain in their lifetime, and most of it comes from four places: the long head of the biceps, the AC joint, the subacromial bursa, and the rotator cuff. All four are sitting a centimeter under your linear probe.
The exam is a fixed circuit of stations. Same order every time, both static and dynamic, and compare with the other side when unsure.
Curated from the POCUS 101 Shoulder Ultrasound Made Easy: Step-by-Step Guide and its stepwise protocol (AC joint · biceps · subscapularis · impingement · supraspinatus). The positioning photos there are essential — this exam is all about arm position.
MSK preset. The structures are superficial; depth stays shallow and gain modest.
Patient on a stool or the edge of the bed, arm positions changing per station. Scanning from behind gives you every window without wrestling the patient.
Every structure in short and long axis. The contralateral shoulder is your built-in normal control — use it liberally.
Arm neutral · palpate along the clavicle laterally to the notch · probe in coronal plane
Walk your fingers along the clavicle until you feel the acromioclavicular notch, then lay the probe across it. You'll see the bright cortical lines of clavicle and acromion with the joint gap between.
Arm neutral, palm up on the thigh · probe transverse over the anterior shoulder
The LHBT sits in the bicipital groove between the greater and lesser tubercles — a bright oval in its bony trench. Trace it in short axis up and down the groove, then rotate for long axis.
Elbow at the side, flexed 90° · externally rotate the arm · probe transverse, medial to the groove
External rotation pulls the subscapularis out from under the coracoid and lays it flat for inspection as it inserts on the lesser tubercle. Scan it in both axes; rotate the arm in and out to watch it slide.
Hand toward the back pocket (extension + internal rotation) · probe over the anterolateral shoulder
The back-pocket position (Crass/modified Crass) rolls the supraspinatus out from under the acromion. It should be a smooth, fibrillar "bird's beak" inserting on the greater tubercle, with the thin subacromial-subdeltoid bursa gliding above it.
For the dynamic test: park the probe at the lateral acromion and have the patient abduct. The cuff and bursa should glide smoothly under the acromion — bunching, catching, or pooling bursal fluid suggests impingement.
Probe just below the scapular spine, parallel to it · the ED's favorite view
From behind, image the glenoid, labrum, humeral head, and infraspinatus. This is the money view for two ED questions:
| Finding | Looks like | Means |
|---|---|---|
| Full-thickness cuff tear | Anechoic gap through the tendon, non-visualized tendon, deltoid sag | Ortho referral; large acute tears in young patients move faster |
| Tendinosis / partial tear | Thickened, heterogeneous, hypoechoic tendon without a through-and-through defect | Conservative management track |
| Biceps tenosynovitis | Fluid halo around the LHBT in the groove | Supports anterior shoulder pain source |
| Subacromial bursitis | Thickened, fluid-filled bursa; pooling with dynamic testing | Impingement syndrome; injection target |
| Joint effusion | Distended posterior recess | Tap if infection is on the table |
| Dislocation | Humeral head off the glenoid on the posterior view | Reduce, then rescan to confirm — before and after sedation wears off |
| Calcific tendinopathy | Bright focus within the tendon with shadowing | Common supraspinatus finding; correlates with pain flares |
Tendon fibers only reflect brightly when the beam hits them perpendicular. Angle off by a few degrees and healthy tendon turns hypoechoic — indistinguishable from pathology. Rock the probe (heel-toe) before calling any dark spot a tear.
Every equivocal finding gets cheaper with a ten-second look at the contralateral side. Symmetric "abnormality" is usually anatomy.
Neutral palm-up for biceps, external rotation for subscapularis, back pocket for supraspinatus. If the arm isn't positioned, the structure isn't visible — no amount of probe skill compensates.
Posterior-view confirmation of reduction while the patient is still sedated saves the second x-ray trip and the re-sedation when the first reduction didn't hold.
In neutral position most of the supraspinatus hides under the acromion. If you skipped the back-pocket position, you didn't examine the most commonly torn tendon — you examined its shadow.
Bursitis and tears travel together but aren't the same call. Trace the tendon fibers themselves before upgrading a bursitis to a tear.
A starting template for the POCUS note. Text in brackets [ ] and pick-lists in { } are fields to complete. Save it as a SmartPhrase, then edit every field to match the actual study.
POINT-OF-CARE ULTRASOUND: SHOULDER
Indication: {shoulder pain : suspected cuff tear : dislocation
assessment} [side ***]
Exam type: Focused / limited MSK, bedside
Operator: @ME@ Interpretation: independent, real-time
Probe: linear
FINDINGS ([right : left])
- AC joint: {normal : widened / step-off}
- Long head biceps tendon: {normal : tenosynovitis : dislocated / absent}
- Subscapularis: {intact : abnormal ***}
- Supraspinatus: {intact : tendinosis / partial tear : full-thickness tear}
- Subacromial-subdeltoid bursa: {normal : bursitis}
- Glenohumeral joint: {normal : effusion : dislocated : reduced / relocated}
IMAGE QUALITY: adequate / limited by [***]
Images saved and archived to [PACS / Qpath / ***].
IMPRESSION: [***].
I personally performed and interpreted this study.
Electronically signed: @ME@ @TD@ @NOW@
Sample template only — not a validated institutional SmartPhrase. Verify wording, image-archival, and attestation requirements against your department's POCUS credentialing, coding, and compliance policies before clinical use. Documentation supports, but does not replace, the medical record and QA workflow.