Chronic Abdominal Pain After Previous Bariatric Surgery: Consider the Abdominal Wall

Background Up to 30% of patients who undergo bariatric surgery experience recurrent abdominal pain within 3 years after the operation. Although some causes for persisting discomfort are well known, a small portion of patients may suffer from an abdominal wall pain associated with Anterior Cutaneous Nerve Entrapment Syndrome (ACNES). Aim of the present study is to discuss incidence, clinical presentation, and treatment outcome in patients with ACNES after bariatric surgery. Methods This retrospective observational cohort study analyzed electronically stored data of patients with ACNES having a history of bariatric surgery. All were treated for ACNES between 2011 and 2017 in a Dutch center of excellence for abdominal wall and groin pain. Success after treatment was defined as a minimal 50% drop in pain level using a Numeric Rating Scale. Results A total of 49 patients (female n = 44, median age 45 (25-63) years) were identified. Four (8%) experienced long-term pain relief after just one abdominal wall infiltration with lidocaine. Ten additional patients reported success after 2-5 injections. A total of 35 unresponsive patients chose to undergo a neurectomy that was successful in 27. Therefore, this step-up approach conferred an 84% success rate. Occurrence of ACNES after bariatric surgery was estimated at 1 in 100 patients. Conclusion ACNES should be considered in the differential diagnosis of ongoing pain following previous bariatric surgery. A treatment regimen including abdominal wall infiltrations using an anesthetic agent or a neurectomy is successful in a vast majority of these patients.