Bilateral Hernia Definition and Diagnosis
A bilateral hernia refers to the presence of hernias on both sides of the body, which requires special consideration in diagnosis and treatment, with an increased injury grade classification compared to unilateral hernias according to the AAST diaphragm injury scale. 1
Definition
- Bilateral hernias occur when there are hernia defects present on both the left and right sides of the body simultaneously 1
- In the context of diaphragmatic hernias, bilateral hernias account for approximately 1-9% of all hernias following blunt trauma 1
- For inguinal hernias, bilateral presentation requires special consideration in treatment approach and surgical planning 2
- The AAST diaphragm injury scale specifically notes that bilateral injuries should be graded one level higher (up to grade III) than their unilateral counterparts, indicating their increased clinical significance 1
Diagnostic Approach
Clinical Presentation
- Patients with bilateral hernias may present with symptoms on both sides, though symptoms can sometimes be asymmetric or more pronounced on one side 1
- Common symptoms include dyspnea (86%) and abdominal pain (17%) in cases of diaphragmatic hernias 1
- For inguinal hernias, bilateral presentation often includes swelling in both groin areas, sometimes accompanied by pain or a dragging sensation 3
- It is crucial to examine both sides thoroughly, as failing to identify bilateral hernias is a common pitfall in diagnosis 2
Diagnostic Imaging
Chest X-ray (both anteroposterior and lateral views) is recommended as the first diagnostic study for patients with respiratory symptoms and suspected diaphragmatic hernias 1
- However, chest X-rays have limited sensitivity (2-60% for left-sided hernias and 17-33% for right-sided hernias) 1
CT scan with contrast enhancement of the chest and abdomen is the gold standard for diagnosing diaphragmatic hernias 1
For inguinal hernias, physical examination can diagnose most cases, but imaging may be necessary in uncertain cases 4
In pregnant patients with suspected non-traumatic diaphragmatic hernias, ultrasonography is suggested as the first diagnostic study, followed by MRI if necessary 1
Diagnostic Laparoscopy
- In stable trauma patients with lower chest penetrating wounds and suspected diaphragmatic hernia, diagnostic laparoscopy is recommended when symptoms and chest X-ray findings are nonspecific 1
- For suspected bilateral inguinal hernias, laparoscopic approaches allow for simultaneous examination of both sides 5
- During TAPP (transabdominal preperitoneal) procedures, the contralateral side should be inspected after patient consent to identify potential occult bilateral hernias 5
Clinical Implications
- Bilateral hernias require more comprehensive surgical planning and may necessitate different approaches than unilateral hernias 5
- The presence of bilateral hernias may indicate underlying connective tissue disorders or abnormal collagen metabolism 5
- Bilateral femoral hernias are extremely rare, especially in males, but carry a high risk of strangulation due to their narrow necks 6
- Patients with bilateral hernias should be evaluated for potential complications on both sides, as strangulation can occur independently 6
Common Pitfalls to Avoid
- Failing to examine both sides for hernias can lead to missed diagnoses, particularly for femoral hernias which have a higher risk of strangulation 2
- Not assessing for complications that require urgent intervention, such as incarceration or strangulation on either side 2
- Misdiagnosis between inguinal and femoral hernias can occur, which may affect the surgical approach 6
- Relying solely on physical examination without appropriate imaging in cases where bilateral hernias are suspected but not clearly evident 4