Jaw exercise therapy for the treatment of trismus in head and neck Cancer: a prospective three-year follow-up study

PURPOSE: This study aims to examine effects of jaw exercise on trismus 3 years following completion of a post-radiotherapy jaw exercise intervention. METHODS: Prospective study including 50 patients with head-and-neck cancer receiving radiotherapy and/or chemotherapy, plus a matched control group. The intervention group underwent 10 weeks of jaw exercise training. Patients were followed pre-and postintervention and 3 years postintervention completion. Outcome measures were maximal interincisal opening (MIO), trismus-related symptoms, and health-related quality-of-life as measured by Gothenburg Trismus Questionnaire, EORTC QLQ-C30, and EORTC QLQ-H&N35. RESULTS: The intervention group had a statistically significantly higher mean MIO compared with the control group (40.1 mm and 33.9 mm, respectively, p < 0.001), reported less trismus-related problems and had an improved health-related quality-of-life when compared with the control group at the 3-year follow-up. These differences were all statistically significant. CONCLUSION: Jaw exercise therapy resulted in increased MIO, less trismus-related symptoms, and improved health-related quality-of-life. Jaw exercise therapy should be initiated early, in a structured manner and continued long-term.