femoral hernia
Summary
A femoral hernia occurs when abdominal or pelvic contents protrude through the femoral canal, below the inguinal ligament. It is more common in women (due to a wider femoral canal) but overall less common than inguinal hernias. Femoral hernias carry a high risk of incarceration and strangulation due to the rigid, narrow boundaries of the femoral canal.
Detail
Femoral hernias occur when abdominal contents (often preperitoneal fat, bowel, or omentum) herniate through the femoral canal, which is bounded by the inguinal ligament anteriorly, the lacunar (Gimbernat's) ligament medially, the pectineal ligament (Cooper's ligament) posteriorly, and the femoral vein laterally. This canal is normally a small space that allows for lymphatic drainage from the lower limb (contains Cloquet's lymph node), making it a naturally narrow, rigid opening.
Epidemiology: More common in women than men, primarily due to a wider pelvis and femoral canal, though inguinal hernias are still more common than femoral hernias even in women. Risk factors include increased intra-abdominal pressure (pregnancy, obesity, chronic cough, constipation), prior groin surgery, and aging (loss of tissue tone).
Clinical presentation: Often presents as a mass below the inguinal ligament, medial to the femoral pulse (helps distinguish from femoral artery aneurysm) and lateral to the pubic tubercle (helps distinguish from inguinal hernia, which is above and medial to the pubic tubercle). Because the femoral canal is a rigid, narrow space, femoral hernias have the highest risk of incarceration and strangulation among the groin hernias—this is a key board fact. Patients may present with bowel obstruction, severe groin pain, or a tender, non-reducible mass.
Diagnosis: Primarily clinical exam; ultrasound or CT can confirm the diagnosis and assess for complications like strangulation.
Treatment: Surgical repair (herniorrhaphy) is generally indicated due to the high risk of strangulation, even if asymptomatic. Approaches include open (McVay repair, which specifically addresses the femoral canal by suturing the conjoint tendon to Cooper's ligament) or laparoscopic mesh repair.
Key distinguishing points for boards: - Location relative to inguinal ligament and pubic tubercle (differentiates from inguinal hernia) - Higher risk of strangulation than inguinal hernias - More common in females - Anatomic boundaries of the femoral canal are testable
Sources
- First Aid for the USMLE Step 1
- Sabiston Textbook of Surgery
- Schwartz's Principles of Surgery
- UpToDate: Classification, clinical features, and diagnosis of inguinal and femoral hernias in adults
Reviewed by AnkiBoss editorial — medical student review. Information here is for study reference only and is not medical advice. Spotted an error? Let us know.