Can a Doppler (Doppler ultrasound) ultrasound detect a tendon rupture?

Doppler Ultrasound for Tendon Rupture Detection

Yes, Doppler ultrasound can detect tendon ruptures, but it has limitations in accuracy compared to MRI, particularly for partial tears.

Diagnostic Capabilities of Ultrasound for Tendon Ruptures

Effectiveness by Tendon Type

• Ultrasound can identify both complete and isolated partial tears of the triceps brachii tendon, though these injuries are rare 1
• For distal biceps tendon injuries, ultrasound has shown varying levels of accuracy:
  • Some studies found a slight statistical advantage of ultrasound over MRI when comparing with surgical findings 1
  • However, ultrasound is at a disadvantage for detecting partial tears and tendinopathy of the biceps tendon 1

Accuracy Metrics

• For complete distal biceps tendon ruptures, ultrasound accuracy (45.5%) is inferior to MRI (86.4%) 1
• For partial biceps tendon tears, ultrasound and MRI have similar accuracy rates of approximately 66.7% 1
• Sensitivity and specificity of ultrasound for biceps tendon tears (62.5% and 20.0%) are inferior to MRI (76% and 50%) 1

Advantages of Doppler Ultrasound

• Doppler imaging is particularly valuable for detecting increased vascularity associated with tendon pathology 1
• Dynamic assessment capabilities allow evaluation of tendon subluxation and dislocation with reported positive predictive value of 100% compared with surgical findings 1
• Can be used to guide interventions such as intrasheath anesthetic injections when a tendon abnormality is detected 1
• More cost-effective and readily available compared to MRI 2

Limitations and Pitfalls

• Ultrasound is highly operator-dependent, requiring expertise for accurate diagnosis 1
• False positive rates can be high - one study showed 33.3% false positives in ultrasound-diagnosed extensor tendon injuries of the knee 3
• Less reliable for detecting partial ruptures, particularly in the Achilles tendon, with a sensitivity of only 0.5 and specificity of 0.81 in one study 4
• Accuracy may be further reduced in obese or very muscular patients 3

Clinical Applications by Anatomical Region

Upper Extremity

• For elbow tendon injuries, ultrasound can detect traumatic ligamentous lesions with the pathology matching clinical symptoms 1
• Hand and wrist tendon pathologies are well visualized with ultrasound, which can determine tear type (complete vs. partial) and assess tendon retraction 5

Lower Extremity

• For quadriceps tendon ruptures, ultrasound has shown reliability in both acute and chronic cases 2, 6
• For Achilles tendon injuries, ultrasound can differentiate full-thickness from partial-thickness tears with 92% accuracy 1

When to Consider MRI Instead

• When ultrasound findings are ambiguous or inconclusive 4
• For partial tears, especially in the proximal Achilles tendon 4
• When precise characterization of tear type is needed for surgical planning 1
• In obese or very muscular patients where ultrasound visualization may be limited 3

In summary, while Doppler ultrasound is a useful first-line tool for detecting tendon ruptures, MRI remains the gold standard for definitive diagnosis, especially for partial tears or in anatomically challenging regions.