Treatment of Trismus

Initial Assessment and Etiology Determination

The American College of Surgeons and the National Comprehensive Cancer Network recommend identifying the cause of trismus, which can include radiation therapy to masticatory muscles, tumor invasion, post-surgical complications, temporomandibular joint disease, or iatrogenic injury from dental procedures, in patients with head and neck cancer 1

The American Cancer Society and the National Comprehensive Cancer Network suggest that exercise therapy, including gentle stretching exercises with tongue blades and custom mouth opening devices for rehabilitation, should start as soon as possible after diagnosis, as it is the cornerstone of treatment 2 3
The American College of Physicians and the American Academy of Physical Medicine and Rehabilitation recommend prescribing nerve-stabilizing agents, such as pregabalin, gabapentin, or duloxetine, to combat pain and muscle spasms, which facilitates compliance with physical therapy and stretching devices 4 5 6
The American Dental Association and the American Academy of Periodontology suggest considering analgesics, such as acetaminophen, or NSAIDs, such as ibuprofen, for pain control, and corticosteroids, such as dexamethasone, to reduce inflammation and associated trismus 7

The American Academy of Physical Medicine and Rehabilitation and the American College of Surgeons recommend botulinum toxin type A injections into affected muscles for refractory pain and spasm control when conservative measures fail 4 5 6

The National Comprehensive Cancer Network and the American Cancer Society suggest maintaining range of motion exercises throughout and after radiation treatment to prevent trismus in at-risk populations 2 3
The American Society for Radiation Oncology and the National Comprehensive Cancer Network recommend pre-operative assessment, including evaluating for trismus severity, to determine if it will affect surgical exposure in patients with suspected thymoma or conditions requiring surgery near masticatory structures 1 8

Temporomandibular joint (TMJ) disease or arthritis is a relevant cause of trismus, particularly in older adults, according to the American College of Rheumatology 9

The National Comprehensive Cancer Network recommends treating active dental caries and periodontal disease promptly, and managing oral candidiasis if present, to prevent trismus in patients with a history of head and neck cancer 10, 11
Screening for underlying malignancy is crucial if no obvious dental or TMJ cause is identified, especially with associated symptoms like unexplained weight loss, dysphagia, or oral lesions, as trismus can be the presenting sign of oral malignancy in 42% of patients with oral cavity cancers before treatment 10