Effectiveness of Sonography in Detecting Clinically Occult Femoral Hernias

The aim of this study was to evaluate the accuracy of sonography for femoral hernia diagnosis in patients with suspected hernias that were not evident on clinical examination.

A retrospective analysis was performed for 39 consecutive patients with 40 clinically suspected but occult femoral hernias and subsequent positive sonographic findings for femoral hernias. Clinical records for all patients were reviewed for surgical outcomes and clinical follow-up. Surgical findings of a femoral hernia sac or widened femoral canal requiring repair, with symptomatic relief after the procedure, were considered positive for a femoral hernia.

Among the 40 femoral hernias examined by sonography, 33 of 40 groins underwent surgical exploration, with 32 true-positive findings and 1 false-positive finding on sonography. The false-positive case was an inguinal hernia at surgery. The accuracy of sonography was 96.9% for those with surgical correlations. The remaining 7 patients did not undergo surgery but had clinical follow-up.

This study confirms high diagnostic accuracy of sonography for nonpalpable femoral hernias in symptomatic groins compared to surgical findings.