Management of trismus after radiation therapy

The purpose of this review is to summarize the current management of radiation-induced trismus. It will provide an overview of radiation-induced trismus' pathophysiology, assessment, diagnosis, and treatment, along with directions for future research.

Despite advances in radiation technology, the proximity of head and neck tumours to the masticatory muscles prevents shielding of these critical structures, increasing the risk of trismus. Trismus has been treated using various techniques including stretching and strengthening exercises in the rehabilitation setting that have resulted in improvements in mouth opening, however, the exercise approach in both research and clinical practice rarely accommodates an individual's goals and priorities. The effect of prophylactic trismus exercises during radiation can be challenging to measure, likely due to exercise adherence with the onset of treatment related toxicities. There is limited support from the literature as to its preventive efficacy. Recent papers provide direction for trismus exercises and devices which may offer greater capacity to individualize treatment and optimize both functional and quality of life outcomes.

The incidence of radiation induced trismus is anticipated to rise along with that of head and neck cancers globally. Trismus carries significant functional and quality of life implications with known limitations and opportunities for optimizing its management.