Anterior Cutaneous Nerve Entrapment Syndrome

F pt with h/o abdominal surgery presents with chronic pain localized to lateral abdominal wall. Pain worse when lying on affected side, changing position, or with increased abdominal muscle tension (e.g. during cough/sneeze); not exacerbated by bowel movements, stress. Denies fever, chills, anorexia, unintended weight loss, change in bowel habits, diarrhea, dark/tarry stools, BRBPR, polyuria, dysuria, vaginal discharge/AUB. No h/o DM. Tenderness is superficial and located near lateral border of rectus abdominis; positive Carnett test on exam.

• Obtain U/S at site of maximum tenderness

• Administer 5 mL lidocaine 2% local injection at site of maximal tenderness; resultant pain reduction of 50% or greater confirms diagnosis

• Treat with 10 mg triamcinolone/1 mL lidocaine 2% trigger point injection; refer for surgical neurectomy if >2 injections required

Notes

• Etiology

  • Often initially misdiagnosed with functional abdominal pain or IBS

  • Rule out injury, surgery and DM as potential causes

• Patients generally able to localize pain location with one finger

• Carnett test: Abdominal pain worse with abdominal muscle tension