Ultrasound-Guided Lidocaine Injection as a Novel Predictor of Response to Botulinum for Patients With Myofascial Pain Syndrome: A Case Report.

Botulinum injection is a well-known non-surgical intervention utilized in the management of myofascial pain syndrome (MPS). However, sparse evidence exists regarding the utility of ultrasound guidance of injectate or lidocaine as a predictive marker of patient response to botulinum toxin A (BTX-A). A 39-year-old male active duty service member demonstrated typical signs and symptoms of MPS. He reported a 10-year history of neck and back spasms that were triggered by exertion but also could occur spontaneously. Based on the characteristic regional motor-sensory defects, treatment options were discussed. With shared decision-making, the patient opted to try ultrasound-guided injection of lidocaine followed by xenomin brand BotoxA. Immediately following lidocaine injection, the patient reported complete relief of symptoms. Both injections were uncomplicated, and the patient reported great reduction in symptoms during the subsequent visit 2 months later. Relief of pain following ultrasound-guided injection of lidocaine may serve as an indicator of successful patient response to BTX-A in patients with MPS.