Treatment of anterior cutaneous nerve entrapment syndrome using an ultrasound-guided transverse abdominis plane block

Abstract

Introduction: Anterior cutaneous nerve entrapment syndrome (ACNES) is increasingly being considered to be a common cause of abdominal pain. Unfortunately, ACNES is a condition that is frequently overlooked and misdiagnosed resulting in chronic abdominal wall pain, unnecessary investigations, procedures, and repeat admissions. Patients diagnosed with ACNES present with well-localized abdominal pain, a positive Carnett’s sign, somatosensory disturbance of the surrounding skin and symptomatic relief secondary to a trigger point injection. Current treatment strategies include modification of physical activity, simple analgesia, trigger point injections, chemical neurolysis, pulsed radiofrequency, and anterior neurectomy. Despite the plethora of treatment modalities, it is evident that a majority of patients will only experience temporary pain relief. Case Series: We describe two cases in which ultrasound-guided transverse abdominal plane blocks have successfully provided long-term symptomatic relief in patients diagnosed with ACNES. The first being a 45-year-old female and the second is a 52-year-old male who both presented with ACNES which were successfully treated with an ultrasound-guided transverse abdominal plane (TAP) block with 20 mL of 0.25% Marcaine and 4 mg of Dexamethasone. Conclusion: We provide evidence supporting the use of an ultrasound-guided TAP block for long-term symptomatic relief in patients with ACNES. However, further research is required to assess its efficacy.