727 - Unsettled cause for unsettling abdominal pain- Clinical Vignette

Patient reported to the sports medicine clinic with chronic left lower abdominal pain for 3 years which started after core workouts. He was seen by multiple specialists, underwent extensive diagnostic evaluations, including colonoscopy, CT and MRI of the abdomen/pelvis, abdominal ultrasound all of which were unremarkable. Minor improvement was reported with home exercises including clamshells, hip flexion, bird-dog pose, pelvic bridge, and therapy.  Naproxen and Tylenol didn’t help. The examination was significant for ⅘ left hip flexion weakness, tenderness to palpation of left lower rectus abdominis muscle, positive left Carnett's sign. On Ultrasound evaluation, tenderness and symptom reproduction to sonopalpation confirmed left lower thoracic anterior cutaneous nerve entrapment syndrome (ACNES.  Ultrasound-guided left 12th thoracic anterior cutaneous nerve perineural steroid injection was administered. His symptoms gradually improved over the next few days, with 100% relief achieved at the 1-month after the injection.

Discussions:

Chronic abdominal wall pain (CAWP) is seen in 30% of patients with chronic abdominal pain. ACNES is the most frequent cause of pain in these cases. Carnett’s sign could be used in clinical practice to diagnose more than 90% of patients with CAWP. Our case emphasizes the importance of considering ACNES as a diagnosis for chronic, undiagnosed, lower abdominal pain. Upon literature review, patients with chronic abdominal pain are often subjected to multiple rounds of unnecessary testing leading to increased cost of healthcare.  

Conclusions:

This case report demonstrates the importance of thorough examination, including the use of point-of-care ultrasound, in diagnosing ACNES in patients with chronic abdominal pain.