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.