What is the recommended approach for assessing and treating an inguinal hernia?

Assessment and Management of Inguinal Hernia

Initial Clinical Assessment

Diagnose inguinal hernia by physical examination alone in the vast majority of patients, reserving imaging only for unclear cases or when complications are suspected. 1, 2

Key Physical Examination Findings

• Examine for an inguinal bulge that increases with crying or straining, which may extend into the scrotum in males or labia in females 1
• Palpate for the "silk sign"—scrotal contents that retract inward on coughing or straining, which is pathognomonic for inguinal hernia with patent processus vaginalis 1
• Always examine both groins bilaterally, as contralateral patent processus vaginalis occurs in 64% of infants younger than 2 months, and failing to do so is a common pitfall 1
• In males, palpate the testis to ensure it is present in the scrotum and not involved in the hernia 1
• Examine for femoral hernias, which have a higher risk of strangulation and are commonly missed 1

Critical Red Flags Requiring Emergency Assessment

Immediately assess for signs of incarceration or strangulation, including:

• Irreducibility of the hernia 1
• Tenderness over the hernia 1
• Erythema, warmth, or swelling over the hernia 1
• Systemic symptoms or signs of SIRS (systemic inflammatory response syndrome) 3

Delayed treatment beyond 24 hours of complicated hernias significantly increases mortality rates, making urgent recognition critical 4, 3

Imaging When Needed

• Use ultrasound when physical examination is inconclusive, particularly in women where diagnosis is more challenging 2, 5
• Ultrasound has 94% accuracy for detecting inguinal hernia presence but only 62% accuracy for differentiating lateral from medial hernias 6
• Reserve MRI for occult hernias when clinical suspicion remains high despite negative ultrasound findings, as MRI has higher sensitivity and specificity than ultrasound 2
• Use CT scanning in emergency settings to assess for complications like bowel obstruction or strangulation, with 56% sensitivity and 94% specificity for reduced wall enhancement indicating strangulation 1

Management Algorithm

For Asymptomatic or Minimally Symptomatic Male Patients

• Watchful waiting is acceptable for asymptomatic primary inguinal hernias in men, as the risk of hernia-related emergencies is low 1, 2
• Counsel patients that the majority will eventually require surgery and discuss surgical risks versus watchful waiting 1
• Advise patients to avoid activities that increase intra-abdominal pressure to prevent incarceration and strangulation 3

For All Other Patients

All inguinal hernias in women should be operated on, as should all symptomatic hernias in men 7, 2

Surgical repair should occur urgently within 1-2 weeks of diagnosis in infants to prevent life-threatening complications including bowel incarceration and gonadal infarction 1

Surgical Approach Selection

• For women and all bilateral hernias, laparoscopic or endoscopic repair (TEP or TAPP) is preferable to open procedures 1, 7
• For primary unilateral hernias in men, either open or laparoscopic repair is appropriate, though laparoscopic approaches result in less chronic pain, faster recovery, and are cost-effective when expertise is available 7, 8
• Mesh-based repair is recommended as first choice over tissue repair, given the pathogenesis involves abnormalities of the extracellular matrix 7, 8
• For femoral hernias, laparoscopic mesh repair is suggested when expertise is available 8

Special Populations

• In preterm infants, repair should occur soon after diagnosis despite higher surgical complication rates, as incarceration risk is also elevated 1
• Preterm infants under 46 weeks corrected gestational age require 12-hour postoperative monitoring due to elevated apnea risk 1
• In pregnant women, watchful waiting is suggested as groin swelling often consists of self-limited round ligament varicosities 8

Common Pitfalls to Avoid

• Not examining both sides for hernias and missing contralateral patent processus vaginalis 1
• Missing femoral hernias, which have higher strangulation risk 1
• Delaying evaluation when any signs of strangulation are present, as symptomatic periods longer than 8 hours significantly affect morbidity 1, 3
• Failing to recognize that physical features of the hernia (size, ease of reduction) do not consistently predict incarceration risk 1