Trismus and cancer treatment

04 November 2024

Phil Silver discusses the treatment options available to clinicians.

Head and neck cancer is relatively uncommon, with around 12,400 new cases diagnosed each year in the UK. Mouth cancer is the most common type, and can be difficult to detect in its early stages. As such, many patients will require invasive procedures for treatment to be effective.

Treatment for head and neck cancer can be intrusive and destructive which, whilst necessary for effective outcomes, can have consequences in the long term. After radiotherapy or surgery for head and neck cancer, patients may experience stiffness in the jaw and facial muscles. If patients are not given the appropriate preventative advice, or follow up care, this can reduce their mouth opening over time. This stiffness is called trismus, otherwise known as lock-jaw, and can have a significant impact on patients and their wellbeing.

Prevalence of trismus

Research suggests that 32 to 50 per cent of all head and neck cancer patients will develop trismus. Stiffness can begin anywhere from a few weeks to months following treatment, with the severity depending on the person. This is because the muscles become tight, restricting the patient’s ability to open their mouth once it has developed.

Patients can easily check their mouth opening by attempting to put three fingers vertically in between their upper and lower teeth. If they can only fit one or two fingers, they may have trismus. After radiotherapy, trismus becomes more common. This is because the blood supply to the jaw bone is limited. In some cases, the jaw bone itself can die (osteoradionecrosis), however this is uncommon.

How can clinicians help

Because trismus is a condition which gets progressively worse, it’s important to monitor patients who are at risk – such as patients who have received radiotherapy for head and neck cancer. Noticing the signs early will enable you and your patient to take action to prevent the stiffness worsening. Ask patients who are undergoing radiotherapy or surgery about any jaw stiffness or pain in the area, even if the symptoms are mild. This will allow you to monitor their situation, and intervene early where appropriate. Additionally, consulting with or referring to a speech therapist can be helpful, for a multidisciplinary approach. Measuring the jaw opening can also be a good indicator, and can help you to monitor the progress of the condition, and any treatment undertaken.

This is essential as, in severe cases, patients are unable to open their mouth at all, making it very difficult to eat, drink, and talk. Trismus can also make it near impossible to clean the teeth properly, causing oral hygiene issues, and increasing patients’ risk for tooth decay and gingivitis. As such, a thorough knowledge of trismus, and appropriate treatment and prevention methods is key for helping patients achieve the best outcomes.

Treatment and prevention

If patients are finding it painful or difficult to eat, recommend that they temporarily adopt a soft food diet, to reduce the strain on the jaw joint. Consulting a dietitian can be helpful here, to ensure patients receive all of the nutrients they need during this time.

Monitoring patients’ oral health is also essential, recommending smaller toothbrushes and antibacterial supplementary oral hygiene products to enable patients to keep levels of bacterial plaque to a minimum, and reduce the risks of oral diseases. Recommending regular appointments with a dental hygienist here can also be helpful, to keep plaque levels down.

With preventative rehabilitation, research shows a 72 per cent increase in oral opening. Jaw exercises can be helpful for reducing stiffness and pain that patients may feel. By creating a personalised exercise plan, encouraging patients to carry them out regularly, jaw exercises can help to stretch the facial tissues and strengthen the muscles in the jaw.

To assist patients with their jaw exercises, clinicians can recommend the OraStretch Press Rehab System. When used as instructed, it can increase the mouth opening by an average of 26mm, dramatically improving patients’ quality of life, stretching and strengthening the jaw to enable more normal function and reduced pain and stiffness. Additionally, when rehabilitation is carried out in the early stages, trismus is found in 68 per cent fewer patients.

Tailored care at the right time

In order to offer their patients the best possible outcomes, clinicians must deliver tailored care at the right time. Early intervention for trismus patients is key for improving range of motion in the jaw, enhancing quality of life, and reducing the need for more invasive procedures down the line. Recommending temporary changes to diet, lifestyle, and oral hygiene can help to minimise the risks to patients, whist keeping them healthy during trismus rehabilitation. Utilising specially designed rehab systems can further improve results, with variations in resistance, and predictable exercises, tailored to each patient’s specific needs.

References available on request.

For more information email info@totaltmj.co.uk