Ultrasound Views for De Quervain's Tenosynovitis
For De Quervain's tenosynovitis, perform a dorsal longitudinal scan over the radial aspect of the wrist, specifically targeting the first dorsal compartment at the radial styloid where the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) tendons are located.
Patient Positioning
- Sitting position with the hand positioned on top of the thigh or on an examining table 1
- The wrist should be in a neutral to slightly ulnar-deviated position to optimally visualize the first dorsal compartment 1
- Dynamic examination with active thumb abduction and extension can help assess tendon gliding and identify areas of stenosis 1
Standard Scanning Technique
Primary View
- Dorsal longitudinal scan (radial) - This is the key view for De Quervain's, scanning along the long axis of the APL and EPB tendons over the radial styloid 1
Complementary View
- Dorsal transverse scan (radial) - Scan perpendicular to the tendons to assess for thickening of the tenosynovial sheath and measure compartment dimensions 1
Critical Diagnostic Features to Identify
Ultrasound is particularly valuable for identifying anatomical variations that affect treatment success:
- Subcompartmentalization - Look for a septum dividing the first dorsal compartment into separate channels for APL and EPB, present in approximately 52% of cases 1, 2, 3
- Thickened, hypoechoic tenosynovial sheath surrounding the tendons 2
- Accessory tendons within the first dorsal compartment 2
- Fluid within the tendon sheath indicating active tenosynovitis 2
Clinical Significance
Identifying subcompartments preoperatively is crucial because it affects both injection technique and surgical planning 1, 2. When multiple subcompartments exist, each must be injected separately for optimal therapeutic effect 3. Studies show that ultrasound-guided injections achieve 97% initial symptom resolution compared to variable results with blind injections 3.
Common Pitfall
The most important pitfall to avoid is failing to identify and inject all subcompartments when performing ultrasound-guided corticosteroid injection 3. Patients with unrecognized subcompartments have a 14% recurrence rate even after injection 3. Always scan thoroughly in both longitudinal and transverse planes to identify any septations before proceeding with injection 3.