When it is not a Spigelian hernia: abdominal cutaneous nerve entrapment syndrome

Abdominal wall pain at the linea semilunaris is classically the result of a Spigelian hernia. If no hernia is detected, these patients may be left with chronic pain without a diagnosis or treatment. A retrospective review was performed of patients presenting with abdominal wall pain at the linea semilunaris between 2009 and 2012. Of the 14 patients, three (21%) were diagnosed with a Spigelian hernia confirmed by imaging. The remaining patients were eventually diagnosed with abdominal cutaneous nerve entrapment syndrome (ACNES). The average delay in diagnosis was 4 years with patients with ACNES suffering twice as long with chronic pain. Patients with a Spigelian hernia and ACNES had different demographics and presenting complaints. Physical examination findings were nondiagnostic. Of the patients with ACNES, five (50%) had resolution of pain with serial nerve blocks alone; another five proceeded to surgical neurectomy with resolution of their pain. Thus, to prevent delay in diagnosis and treatment, patients with chronic abdominal wall pain at the linea semilunaris should first be ruled out for Spigelian hernia. Then, they should be evaluated and treated for ACNES.