ID:15869 Intercostal Neuralgia With Allodynia Following Colonoscopy Successfully Treated With Temporary Peripheral Nerve Stimulation

Abstract

52-year old male referred for 10 months of persistent anterior chest wall pain localized in the right T6 & T7 distribution. He developed this pain following routine screening colonoscopy. Pain is described as stabbing and ranges from 1-6/10 in intensity on the numerical pain rating scale (NPRS) and is aggravated by postural shifting, ambulating and activities such as driving. Additionally, the patient describes severe pain allodynia from stimuli such as contact with overlying clothing, bedsheets and sleeping on the affected side. He has taken measures to minimize these exposures. Patient reports treatment initially targeting a myofascial etiology with trigger point injections of local anesthetic. These interventions were given in addition to 10% topical lidocaine ointment and duloxetine. He states the topical lidocaine ointment is the only treatment that offered partial relief to the persistent nature of his symptoms. Examination reveals a cardboard cut-out taped to his skin to keep his shirt from making contact with his skin, allodynia was confirmed to light touch. Imaging modalities including chest/abdominal radiographs and MRI revealed no discernible pathology. Given clinical symptoms of neuropathic pain in a thoracic intercostal nerve distribution, diagnostic right T6 and T7 intercostal nerve blocks followed by therapeutic injections both under ultrasound guidance were performed (1). Lidocaine ointment and duloxetine was continued. At 3 months follow up, he describes having 100% relief initially but symptoms eventually returned to baseline. He proceeded to temporary peripheral nerve stimulation (PNS) of the right T6 and T7 intercostal nerves as a refractory treatment option.