Belly dancer syndrome
abdominal pain from rhythmic diaphragm contractions with abdominal wall movement
Can be treated with muscle relaxer or a benzodiazepam. This is a form of dystonia or movement disorder. Botulinum toxin injection into diaphragm in experienced hands should help too.
Belly Dancer Syndrome. An Unusual Cause of Abdominal Pain. Ossella, Chiara, MD, et al . Pediatric Emergency Care: August 8, 2018 - Volume Publish Ahead of Print - Issue – p doi: 10.1097/PEC.0000000000001566