Greater Trochanteric Syndrome: Gluteal Tendinopathy vs Trochanteric Bursitis on Ultrasound
Clinical Context
Greater trochanteric pain syndrome encompasses pathology of the gluteal tendons and bursitis in the trochanteric region. The core question in differential diagnosis is directly posed in the literature: “bursitis or tendinopathy?” (Ruta S, Quiroz C, Marin J, et al. Ultrasound evaluation of the greater trochanter pain syndrome). Ultrasound is used as a primary assessment method with correlation to MRI, surgical, and histological data (Kong A, Vander Vliet A, Zadow S; Fearon AM, et al.).
Gluteal Tendinopathy
The tendons of the gluteus medius and minimus attach to the greater trochanter. Common ultrasound criteria for tendinopathy (outside the verified Medtrain database) include:
- Thickening of the tendon;
- Hypoechogenicity — diffuse or focal;
- Loss of fibrillar pattern — longitudinal fibers cease to differentiate;
- Calcifications — hyperechoic inclusions in chronic processes;
- Enthesis bone changes — cortical irregularity at the attachment site.
The assessment of MRI and ultrasound signs of gluteal tendinopathy in this syndrome is supported by literature (Kong A, et al. MRI and US of gluteal tendinopathy in greater trochanteric pain syndrome).
Trochanteric Bursitis
Bursitis is visualized as a distended bursa with fluid content. The atlas directly shows an example: “Longitudinal US shows a distended subgluteus medius bursa deep to a normal gluteus medius tendon [and] the greater trochanter” (Griffith JF) — indicating a distended subgluteal bursa with an intact tendon. Such a finding suggests bursitis without accompanying tendinopathy.
The Role of Doppler Imaging
Color Doppler imaging helps confirm active inflammation of the bursa: in acute bursitis, peribursal hyperemia is noted — “significant hyperemia of the peribursal soft tissues, consistent with acute inflammation” (Griffith JF). In severe inflammation, “severe peripheral hyperemia” is described, with subsequent confirmation of the content’s nature upon aspiration.
Comparative Table
| Feature | Gluteal Tendinopathy | Trochanteric Bursitis |
|---|---|---|
| Main Substrate | Tendon (thickening, hypoechogenicity, loss of fibrillarity) | Distended bursa with fluid |
| Tendon Condition | Pathologically altered | May be normal (distended bursa deep to a normal tendon) |
| Color Doppler | [specify] | Peribursal hyperemia in acute inflammation |
Technical Scanning Nuance
When assessing tendons, it is important to exclude anisotropy artifact: when the beam is not perpendicular, the fibrous structure appears falsely hypoechoic, mimicking tendinopathy. To eliminate this, tilt the transducer (heel-toe maneuver, 5–15°); if the “finding” disappears upon tilting, it is an artifact, not pathology.
Frequently asked questions
How to distinguish bursitis from tendinopathy in greater trochanteric syndrome?
Bursitis is visualized as a distended bursa with fluid, often against a background of a normal tendon; in tendinopathy, the tendon itself is altered (thickening, hypoechogenicity, loss of fibrillar pattern).
What does color Doppler imaging reveal in trochanteric bursitis?
In acute inflammation, peribursal hyperemia of the soft tissues is observed, consistent with acute inflammation; in severe cases, severe peripheral hyperemia is noted.
Can the tendon be normal in bursitis?
Yes. The atlas describes an example of a distended subgluteal bursa located deeper than a normal gluteus medius tendon.
How to avoid confusing tendinopathy with anisotropy artifact?
Tilt the transducer 5–15° (heel-toe maneuver): when the beam is perpendicular, the false hypoechogenicity disappears — indicating it is an artifact, not pathology.
Is ultrasound correlated with surgery and histology in this syndrome?
Yes, the literature has evaluated the correlation of ultrasound data with surgical and histological findings (Fearon AM, et al.).