Hydroxyapatite deposits in the rotator cuff (supraspinatus most often): hard, shadowing deposits are formative; soft, non-shadowing ones are resorptive and painful — the phase decides barbotage.
Orient first
- Resorptive phase: acute pain, bursitis, deposit migration into the bursa or bone.
- Deposits over about 5 mm that are symptomatic are candidates for ultrasound-guided lavage (barbotage) — verify local criteria.
- Calcium can erode into the greater tuberosity and mimic a tumour.
Acquire the study
- High-frequency linear probe with standard rotator cuff positions (Crass/modified Crass); power Doppler.
The manoeuvre
- Deposit within the tendon: size in mm, posterior acoustic shadow (hard) vs none (soft, fluid-like).
- Power Doppler hyperaemia around it (resorption).
- Subacromial bursa: thickening or fluid, intrabursal calcium.
- Tendon tear alongside the deposit.
What confirms it
- Calcium within the cuff tendon on radiograph or ultrasound in a patient with shoulder pain.
What licenses you to exclude it
- No calcium on radiographs in two rotations excludes a clinically relevant deposit.
The classic misread
- Barbotage of a formative, asymptomatic deposit.
- Calling intraosseous migration a tumour.