1306 - Treatment of Spastic Trismus Secondary to Stroke With Botulinum Toxin A Injection in the Setting of Temporalis Wasting: A Case Report

Case Diagnosis: Spastic Trismus Secondary to Stroke

Case Description:
A 57-year-old male with a past medical history of hypertension and an ischemic stroke involving the left cerebral hemisphere, left pons, right thalamus, and right frontal lobe, presented to an acute inpatient rehabilitation facility with left-sided spastic trismus secondary to stroke. To treat the trismus, 50 units of botulinum toxin A were injected into the left masseter. Due to temporalis wasting, the left temporalis muscle was not injected. Due to the patient’s edentulism, the maximal inter-gingival opening between the mandibular and maxillary gingivae was measured to assess for improvement in mandibular depression. At rest, the initial left-sided inter-gingival opening was 1 cm. With active mandibular depression, the initial maximal left-sided inter-gingival opening was 1.4 cm. By weeks 2, 3, and 7, the maximal left-sided inter-gingival opening increased to 2, 2.3, and 2.8 cm respectively. Functional improvements with oral care tasks and suctioning were noted.

Discussions:
Case reports that discuss botulinum toxin A injections to treat spastic trismus secondary to stroke have discussed injecting the masseter and temporalis muscles as target sites. This case report discusses a unique case in which a patient with unilateral spastic trismus secondary to stroke also had temporalis wasting. Therefore, botulinum toxin A was injected in only the left masseter to treat the unilateral spastic trismus.

Conclusions:
Botulinum toxin A injection can be injected into the left masseter to treat spastic trismus secondary to stroke in a patient with temporalis wasting to improve patient’s mandibular range of motion and functional independence with oral care and suctioning tasks.