Bilateral Hernia Diagnosis and Treatment

Definition and Classification

A bilateral hernia is defined as the presence of hernias on both sides of the body, requiring special consideration in diagnosis and treatment, with an increased injury grade classification compared to unilateral hernias according to the AAST diaphragm injury scale 1, 2
Bilateral hernias occur when there are hernia defects present on both the left and right sides of the body simultaneously 3
In the context of diaphragmatic hernias, bilateral hernias account for approximately 1-9% of all hernias following blunt trauma 3
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, 5

Patients with bilateral hernias may present with symptoms on both sides, though symptoms can sometimes be asymmetric or more pronounced on one side 2
Common symptoms include dyspnea (86%) and abdominal pain (17%) in cases of diaphragmatic hernias 6
It is crucial to examine both sides thoroughly, as failing to identify bilateral hernias is a common pitfall in diagnosis 4
Chest X-ray (both anteroposterior and lateral views) is recommended as the first diagnostic study for patients with respiratory symptoms and suspected diaphragmatic hernias 5, 6
CT scan with contrast enhancement of the chest and abdomen is the gold standard for diagnosing diaphragmatic hernias 7, 8
CT has a sensitivity of 14-82% and specificity of 87% 7
Key CT findings include diaphragmatic discontinuity, "dangling diaphragm" sign, "dependent viscera" sign, and the "collar sign" 8
In pregnant patients with suspected non-traumatic diaphragmatic hernias, ultrasonography is suggested as the first diagnostic study, followed by MRI if necessary 7, 6

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 5, 2

Failing to examine both sides for hernias can lead to missed diagnoses, particularly for femoral hernias which have a higher risk of strangulation 4
Not assessing for complications that require urgent intervention, such as incarceration or strangulation on either side 4