A new high-frequency ultrasound classification of De Quervain tenosynovitis.

Purpose: This study aimed to introduce a new high-frequency ultrasound classification of De Quervain tenosynovitis based on a large group of patients. Detailed characteristics of classification are also reported.

Methods: From January 2014 to February 2024, patients diagnosed with De Quervain tenosynovitis were retrospectively reviewed. High-frequency ultrasound (7-14 MHz) scanning was performed to identify the anatomy of the extensor pollicis brevis and abductor pollicis longus tendons, presence of intertendinous septa, and pathologic changes. The affected wrist was compared to the contralateral wrist.

Results: 453 patients were included: 65 male and 388 female; mean age, 46 ± 27 years (range, 24-65 years). Symptom duration was 14 ± 27 weeks. Disease types were type 0 (n = 5), type 1 (n = 195), type 2a (n = 72), type 2b (n = 18), type 2c (n = 50), type 3 (n = 59), type 4 (n = 45), and type 5 (n = 9). Mean retinacular thickness was 2.1 ± 0.5 mm in affected wrists and 0.4 ± 0.1 mm in contralateral wrists (p < 0.01). The intercompartmental septum was significantly thicker on the affected side (1.2 ± 0.7 mm) than on the asymptomatic side (0.1 ± 0.4 mm) (p < 0.01).

Conclusions: This novel classification provides detailed ultrasonographic characteristics of De Quervain tenosynovitis, based on a large population of patients. It may help in selecting treatment and predicting outcome. However, relevance and therapeutic significance remain to be demonstrated.

Level of evidence: Therapeutic study, Level IV.