TRISMUS: A LATE COMPLICATION OF HEAD AND NECK RADIOTHERAPY

Objective To investigate trismus prevalence and associated factors in patients with head and neck cancers treated with radiotherapy. Study Design This cross-sectional study evaluated 86 patients with head and neck cancers with treatment finished for at least 3 months. During evaluation, the patients were questioned about the difficulty of opening the mouth before the antineoplastic treatment. The mouth opening was performed with a millimeter ruler and trismus was considered as an interincisal mouth opening smaller than 35 mm. Characteristics such as tumor location, staging, radiation dose, and type of treatment were obtained from medical records. Results Half of the patients studied presented with trismus after radiotherapy, with a mean mouth opening of 24.81 ± 6.06 mm. Of these, 25.6% (P = .002) reported having difficulty in opening their mouths before the antineoplastic treatment. Patients with primary tumor in mouth and oropharynx had more trismus than those in the hypopharynx and larynx (P = .008); there was no association of trismus with tumor staging, dose, or type of treatment. Conclusions Trismus had a high prevalence and is an important late complication of radiotherapy in the head and neck.