Sonographic Assessment of a Spigelian Hernia

Spigelian hernias are a rare type of lateral ventral hernia that arises through a defect in the spigelian fascia within the anterior abdominal wall. This type of hernia can be either congenital or acquired. Herniation occurs due to weakness or a defect in the transversus aponeurotic layer between the rectus abdominis muscle medially and the semi-lunar line laterally. Due to difficulty in accurately diagnosing spigelian hernias and the risk of strangulation of herniated contents, surgical repair is often recommended. A spigelian hernia case is presented in which sonography was used in the assessment and diagnosis of the abnormality. The case report highlights important diagnostic features for differentiating a spigelian hernia from other forms of abdominal wall hernia so that proper diagnosis and surgical repair can be accomplished.