Head and neck muscle spasm after radiotherapy: Management with botulinum toxin A injection

Objective: To introduce the concept of neck muscle pain and spasm after radiotherapy and its treatment with botulinum toxin A. Design: Case series. Setting: Ambulatory patients at a tertiary care medical center. Patients: Individuals who had undergone primary or adjuvant radiotherapy for treatment of carcinoma of the head and neck were asked about painful spasms of the neck musculature. A volunteer sample was used. If they desired treatment with botulinum toxin A, they were included in the study, Intervention: Patients received botulinum toxin A injections to the affected sternocleidomastoid muscle(s) in 1 or 2 locations. Outcome Measure: Subjective pain relief. Results: Four of 6 patients with painful tightness of the neck who received botulinum toxin A injections to the sternocleidomastoid muscle achieved pain relief. Conclusions: A subset of patients with irradiation-induced cervical muscle spasm benefit from treatment with botulinum toxin A injections. Further study is needed to more clearly define the entity and treatment.