Tendinitis, Tears and Bursitis: The Power of Dynamic Musculoskeletal Ultrasound

Dr. Segnini
Dec 18, 2025
3 min read

Updated: Dec 22, 2025

Dr. Segnini Dynamic musculoskeletal ultrasound

The Next Dimension in Injury Diagnosis Dynamic musculoskeletal ultrasound

When there is pain in a shoulder, elbow, or heel, the cause is usually in the soft tissue structures: tendons, muscles, and bursae . While other imaging techniques offer static images, musculoskeletal ultrasound provides a "real-time video ," allowing these structures to be seen in motion. This dynamic capability makes it an irreplaceable tool and the first choice for sports, work-related, and degenerative injuries.

Why is Dynamic Ultrasound Revolutionary?

The key advantage of ultrasound in this area is the ability to assess anatomy in motion . Many injuries only become apparent or worsen with movement.

Direct Interaction: The radiologist can move the joint, ask the patient to contract a muscle, or apply pressure with the transducer to reproduce the exact pain.
Diagnosing " Impingement ": Watch live how a tendon gets caught between two bones during arm elevation.
Identifying Instabilities: Detecting subtle tendon dislocations that occur only in certain positions.
Therapeutic Precision: Guiding infiltrations with millimeter accuracy to the exact area of the injury.

Ultrasound Findings by Injury: The Signature of Each Problem

1. Tendinitis and Tendinosis (Tendon Degeneration)

Normal Appearance: A healthy tendon looks like a fibrillar structure, with hyperechoic (white) parallel lines , like the strings of a violin.
Signs of Pathology:
- Hypoechogenicity : Dark areas (edema, degeneration) that break the fibrillar pattern.
- Diffuse or Focal Thickening: The tendon loses its thin and regular shape.
- Neovascularization ( Doppler) Power ): The appearance of new blood vessels (seen as colored spots on Doppler ultrasound ) within the tendon is a sign of attempted repair and is strongly associated with pain. It is typical in tendinosis. " Achilles tendon " or "tennis elbow" ( epicondylitis ).
- Calcifications: Bright spots or bands ( hyperechoic ) that cast an acoustic shadow.

2. Tendon and Muscle Tears (Ruptures)

Ultrasound clearly differentiates the type and severity of the rupture:

Partial Tear: A discontinuity is observed in some, but not all, of the tendon or muscle fibers. It appears as a cleft or anechoic (black) area that does not extend through the entire thickness. This is critical for conservative treatment decisions.
Complete Tear (Total Rupture): Complete rupture of the fibers. The ends of the ruptured tendon usually retract, leaving a hypoechoic space (hematoma) between them. This is the definitive finding in a "rotator cuff tear" or "Achilles tendon rupture".
Muscle Tear (" Pull " or " Strain "): Visualized as a hypoechoic area (edema/hematoma) between muscle fibers, often with loss of normal architecture. Ultrasound can determine the grade (I, II, or III).

3. Bursitis (Inflammation of the Bursa)

Normal Appearance: A healthy bursa is a thin, virtual cleft, barely visible.
Inflamed Appearance: The bursa becomes distended with fluid, appearing as a well-defined anechoic (black) structure over the joint or tendon. Classic examples:
- Subacromial-Subdeltoid Bursitis (shoulder): Fluid between the rotator cuff and the acromion.
- Olecranon bursitis (elbow): "Chicken egg" at the tip of the elbow.
- Retrocalcaneal bursitis (ankle): Inflammation between the Achilles tendon and the calcaneus.

The Dynamic Exploration Protocol Dynamic musculoskeletal ultrasound

Static Evaluation at Rest: The structures are identified, and signs of thickening, fluid, or rupture are looked for.
Dynamic Assessment: The crucial part. The patient is asked to perform specific movements:
- Shoulder: Abduction and rotation to assess rotator cuff impingement.
- Wrist/Ankle: Resistance movements to tighten specific tendons.
- Knee: Flexion-extension to assess the patellar tendon.
Palpation with the transducer: To accurately locate the point of maximum pain ("reproducible discomfort sign").
Color/ Power Doppler : Activated to detect neovascularization in tendinopathies or increased flow in active bursitis.
Comparison: The healthy side is usually explored to compare echogenicity and thickness.

Advantages over Magnetic Resonance Imaging (MRI)

Both are excellent, but ultrasound offers unique advantages in this context:

Dynamism: The RM is static.
Higher Spatial Resolution: For very shallow structures.
Interactivity and Instant Feedback : Direct relationship with the patient.
Accessibility and Lower Cost.
Real-time guidance for injections.

MRI remains superior for evaluating the interior of joints ( labrum , cartilage) and occult bone lesions.

Conclusion: From Image to Targeted Treatment

Musculoskeletal dynamic ultrasound has transformed the approach to soft tissue injuries. It has evolved from a simple diagnostic method into an interactive clinical-surgical tool . It allows not only for precise identification of the injury ( tendinosis , partial supraspinatus tear, bursitis), but also for minimally invasive treatment guidance (precise injections) and the establishment of a realistic prognosis based on the extent of the damage. For both patient and physician, this translates into certainty, precision, and a clearer path to recovery.