Spigelian hernias are uncommon and difficult to diagnose because of their l
ocation in the aponeurosis in the anterior abdominal wall. When they occur
on the right side, the symptoms can include nonspecific abdominal pain mimi
cking appendicitis. We present an adult with right lower quadrant abdominal
pain due to an incarcerated spigelian hernia and acute appendicitis. Early
recognition and prompt surgical treatment were important to the successful
treatment of our patient.