300 Section - Diagnostic Accuracy of Sonographic Measurements for Trigger Finger

To evaluate the diagnostic accuracy of ultrasonographic measurements in trigger finger and establish standardized cut-off values for sonographic parameters.

Design: This cross-sectional analytical study included fifty-five patients with clinically diagnosed trigger fingers, providing a total of 60 pairs of affected and contralateral unaffected fingers. Ultrasonographic measurements of A1 pulley, flexor tendon, and volar plate thickness, as well as hypervascularity assessment, were compared between the affected and unaffected sides. Diagnostic performance was assessed using receiver operating characteristic (ROC) curve analysis.

Results:

A1 pulley thickness demonstrated excellent diagnostic accuracy (AUC 0.92; cut-off 0.55 mm; sensitivity 71.7%, specificity 96.7%). Flexor tendon and volar plate thickness showed lower diagnostic performance (AUC 0.68 and 0.62, respectively). Hypervascularity was detected exclusively in affected fingers (16.7%), yielding perfect specificity (100%) but low sensitivity. All structural measurements were significantly greater in affected fingers compared to unaffected fingers.

Conclusion: A1 pulley thickness is the most accurate ultrasonographic marker for diagnosing trigger finger. Hypervascularity, despite its low sensitivity, offers perfect specificity and may serve as a confirmatory finding .