Ultrasonographic and elastographic parameters of the common extensor tendon at the lateral aspect of the elbow
| Parameters | Measurements |
| Maximal tendon thickness* | Centimetres (cm) |
| Tendon echogenicity† | Grade 0: normal Grade 1: hypoechogenicity <30% Grade 2: hypoechogenicity 30%–70% Grade 3: hypoechogenicity>70% and anechoic fissures Grade 4: full-thickness tear or complete tendon detachment |
| Enthesophyte | Grade 0: absent Grade 1: present |
| Tendon calcifications | Grade 0: absent Grade 1: hyperechogenic without acoustic shadowing Grade 2: hyperechogenic with acoustic shadowing |
| Color Doppler ultrasound‡ | Grade 0: no pixel Grade 1: a few pixels Grade 2: ≤50% of the tendon surface Grade 3: >50% of the tendon surface |
| Power Doppler ultrasound‡ | Grade 0: no pixel Grade 1: a few pixels Grade 2: ≤50% of the tendon surface Grade 3: >50% of the tendon surface |
| Radial collateral ligament echostructure | Grade 0: normal Grade 1: hypoechogenic, thickened, irregular or partial tear Grade 2: complete tear |
| ARFI-mode elastography | Mean shear wave velocity
|
*Measured at the base of the lateral epicondyle, perpendicular to tendon with transducer in long axis.
†Determined on a long axis image; degree of hypoechogenicity determined as % of tendon surface.
‡Assessed on long axis image of the tendon.
ARFI, acoustic radiation force impulse; SWV, shear wave velocities.