Know Cancer

forgot password

Prophylactic Training for the Prevention of Trismus in Connection With Radiation Therapy - a Randomised Study

18 Years
Open (Enrolling)

Thank you

Trial Information

Prophylactic Training for the Prevention of Trismus in Connection With Radiation Therapy - a Randomised Study

Summary of the study programme


During Radiation therapy to the mouth, throat or trachea can fibrosis often occur in the
chewing muscles round the jaw causing a development of trismus (a limited jaw mobility).
Trismus can cause pain, difficulty in eating, swallowing, speech and difficulty with general
mouth hygiene. Despite the fact that this condition has been documented in older literature,
there is limited research in the incidence of trismus. There is need of randomised studies
to investigate the prevention of trismus both under and during Radiation Therapy.


The specific aims of this study are to investigate the effectiveness of Prophylactic
training with a muscle warm-up programme and a mechanical device (TheraBite) to prevent
trismus during Radiation Therapy and one year after completed therapy. The study also aims
to investigate the incidence of radiotherapy-induced trismus in patients who receive
radiotherapy to the masseter, temporalis, pterygoid muscles. Finally the study investigates
whether trismus affects quality of life.



Sixty consecutive patients, from two different radiation clinics in Sweden, are randomised
into the two different groups using a computer programme.

Treatment procedures

1. Intervention group: Daily training with a programme for TheraBite that trains passive
movement, preceded by a warm-up programme. Mouth opening measurements are made once a
week during treatment at the end of radiotherapy,three, six and 12 months after

2. Control group: Receiving traditional radiation therapy with nursing care, measuring the
patients mouth opening once a week during treatment, at the end of radiation
therapy,three, six, and 12 months after treatment. The same training programme as group
one is offered to this group as soon as evidence of trismus develops.

This training is recorded by the patient in a log book. Weight, height, Mucositis analysis
and quality of life are made before the commencement of radiation therapy, at the end of
radiation therapy, three, six, and 12 months after treatment. The patient's weight is
measured every week.


The results of this study will give new and vital information that can give a basis to
develop a clinical method of identifying and treating cancer patients who suffer from
trismus. Thus giving new knowledge which can be used to formulate clinical practices.

Inclusion Criteria:

- Age 18 or older

- Be able to communicate and understand the Swedish language.

- Compliance with training programme and follow-up during the study time period.

- Planed radiotherapy dose of at least 15Gy to the jaw muscles.

- Tooth 11 and 41 intact.

Exclusion Criteria:

- An operation in the target area that has already affected jaw mobility.

- Jaw measurement under 35mm.

Type of Study:


Study Design:

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Prevention

Outcome Measure:

Change in Jaw mobility measurement during Radiotherapy

Outcome Description:

Proportion of participants free from trismus at the end of Radiotherapy.

Outcome Time Frame:

Up to 7 weeks

Safety Issue:


Principal Investigator

Sussanne Börjeson, Med dr

Investigator Role:

Principal Investigator

Investigator Affiliation:

Department of Medicine and Care, Division of Nursing Sciences, Faculty of Health Sciences, Linköping University, Sweden


Sweden: Regional Ethical Review Board

Study ID:




Start Date:

February 2010

Completion Date:

December 2013

Related Keywords:

  • Trismus
  • Trismus
  • Cancer
  • Radiotherapy
  • Quality of life
  • Trismus