General Surgery

Femoral Hernia

Abdominal contents push through the narrow, rigid femoral canal below and lateral to the pubic tubercle, and because that canal is tighter and less compliant than the inguinal canal, femoral hernias carry a much higher risk of strangulation and are treated as surgical emergencies until proven otherwise.

In a nutshell

A femoral hernia pushes through the narrow, rigid femoral canal below and lateral to the pubic tubercle. That rigidity gives contents little room to move, so femoral hernias strangulate far more readily than inguinal hernias and are managed urgently even when small and reducible.

Classic presentation

A small, firm groin lump below and lateral to the pubic tubercle, more often in a woman, sometimes already irreducible or tender at first presentation.

Key points

Femoral hernias emerge below and lateral to the pubic tubercle; inguinal hernias emerge above and medial to it: this single landmark is the key discriminator.
The femoral canal's rigid, narrow boundaries give trapped bowel little room, which is why femoral hernias have a substantially higher strangulation risk than inguinal hernias.
Femoral hernias are more common in women, reflecting a proportionally wider female pelvis and femoral canal.
Unlike inguinal hernias, watchful waiting is not appropriate: even an asymptomatic, reducible femoral hernia warrants urgent surgical repair.
A small, unimpressive-looking lump does not equal low risk; danger tracks the tightness of the neck, not the size of the visible swelling.

First-line investigation

Clinical examination localising the lump below and lateral to the pubic tubercle; ultrasound if the diagnosis is uncertain.

Management

Recognise the high-risk anatomy

A lump below and lateral to the pubic tubercle is femoral until assessed otherwise; arrange prompt surgical review even if it is small, painless and reducible.^1,3

Identify obstruction or strangulation

Irreducibility, severe or constant pain, skin inflammation, vomiting, distension, absolute constipation or systemic illness requires emergency hospital and surgical assessment; do not delay for imaging.^1,3

Avoid forceful reduction

Do not repeatedly or vigorously manipulate a tender or systemically unwell lump because non-viable bowel could be reduced and the diagnosis obscured.^1,3

Repair promptly

Use emergency exploration for obstruction or strangulation, including bowel assessment and resection when necessary; arrange expedited repair for a reducible femoral hernia rather than watchful waiting.^1,3

Safety-net after repair

Give wound, pain and activity advice and return precautions for fever, worsening pain, vomiting, distension, wound redness or a recurrent irreducible lump; use current BNF and local surgical protocols for medicines.^3,4

Exam traps

Do not label every groin lump 'inguinal hernia' by default: check the position relative to the pubic tubercle, especially in women.
A small femoral hernia can already be strangulating; size does not correlate with risk the way it might be assumed to.
Watchful waiting, sometimes reasonable for a minimally symptomatic inguinal hernia, is not appropriate for a femoral hernia given its strangulation risk.
A femoral hernia can mimic an enlarged lymph node or saphena varix: reconsider the diagnosis if a 'lymph node' in the groin is tender, enlarging, or associated with bowel symptoms.

Illustrations

Anatomy of the femoral canalDiagram of the femoral triangle showing the femoral canal medial to the femoral vein, bounded by the inguinal ligament, pectineal ligament and lacunar ligament, with the pubic tubercle marked.PassFinals · original

Inguinal versus femoral hernia positionIllustration comparing hernia emergence above and medial to the pubic tubercle (inguinal) against below and lateral to it (femoral).PassFinals · original

Incarcerated femoral hernia on CTAnnotated multiplanar CT showing a right femoral hernia sac below the inguinal ligament, with associated small-bowel dilatation from incarceration and obstruction.Hellerhoff, Wikimedia Commons · CC-BY-SA-4.0

Key sources

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.