Abdominal Anterior Cutaneous Nerve Entrapment Syndrome: Case Report of An Overlooked Diagnosis

Introduction: Abdominal Anterior Cutaneous Nerve Entrapment Syndrome (ACNES) is a chronic abdominal pain condition caused by entrapment of thoracoabdominal nerve branches in the abdominal wall. It is often misdiagnosed due to nonspecific symptoms resembling gastrointestinal issues. Hydrodissection, a minimally invasive technique, involves injecting fluid to release entrapped nerves and alleviate pain. This case highlights successful pain relief in ACNES using ultrasound-guided hydrodissection. Methods: A case report of a 27-year-old male pilot presented with chronic lower abdominal pain for five months, worsened by sitting post varicocele operation. The patient reported having persistent abdominal pain with a Numeric Rating Scale (NRS) score of 5–6. Despite undergoing prolotherapy and radiofrequency targeting the left ilioinguinal nerve, the pain intensified to an NRS of 8–9. Examination revealed a positive Carnett’s sign, suggesting ACNES. Hydrodissection with lidocaine under ultrasound guidance was performed. Result: Post-hydrodissection, the patient reported significant pain relief, with his NRS score decreasing from 8–9 to 0–1. He experienced near-complete resolution of chronic abdominal pain without adverse effects, demonstrating hydrodissection's effectiveness. Conclusion: Recognizing ACNES as a potential cause of chronic abdominal pain is essential for targeted intervention.