Trismus: modern pathophysiological correlates

Computed tomography evaluation of alterations in the masticator space due to invasion by malignant head and neck neoplasms

Objective

To evaluate alterations in the masticator space due to the dissemination of malignant neoplasms originating from the tonsillar fossa, retromolar trigone, maxillary sinus, or nasopharynx, using computed tomography (CT), as well as to correlate the presence of trismus with the CT findings and the dimensions of the tumor.

Materials and Methods

We evaluated the medical records of 65 patients with malignant tumors in the regions described. The images were analyzed by two physician examiners, working independently, who were blinded to the clinical data. In the evaluation of the masticator space, the following parameters were considered: symmetry with the contralateral space; obliteration of the fat plane, retromolar trigone, or pharyngeal space; edema/atrophy of the medial or lateral pterygoid muscles; and destruction of the mandibular ramus.

Results

Obliteration of the fat plane was found in 69.2% of the patients. Asymmetry, edema/atrophy, and bone destruction were detected in 27.7%, 26.2%, and 20.0% of the patients, respectively. Trismus was identified in 15.4% of the patients. Of the patients with trismus, 90.0% had stage T4 tumors, compared with only 43.8% of those without trismus. Trismus was 11.6 times more common among the patients with stage T4 tumors than among those with lower-stage tumors. Neoplasms of the tonsillar fossa and retromolar trigone collectively accounted for 95.0% of the cases. The CT scans showed edema/atrophy of the pterygoid muscles in 60.0% of the patients with trismus and in 21.8% of those without. An association was observed between T4 tumor stage and edema/atrophy of the pterygoid muscles. In addition, the risk of trismus was 5.4 times higher among the patients with stage T4 tumors.

Conclusion

In our patient sample, the most common finding was obliteration of the fat plane, followed by asymmetry and edema/atrophy. Most of the patients with T4 tumors had trismus, together with edema/atrophy of the pterygoid muscles.

When dental extractions go wrong: An overview of common complications and management

The extraction of teeth carries a risk of associated complications, some of which may be predicted, providing an opportunity for them to be prevented or their effects minimised. Prior to embarking on any extraction, the dentist must be confident that they are able to deal with any complication that may arise. This paper provides an overview of the complications of dental extraction which are commonly encountered, considers the factors which predispose to them arising, suggests how the risk of them occurring can be reduced, and describes how they should be managed.

Trismus caused by paraneoplastic brainstem encephalitis

We discuss the assessment and differential diagnoses of a middle-aged man who presented with trismus, double vision and behavioural problems. MRI scan of the brain was initially normal, but a month later showed high signal in the hippocampal region on fluid attenuated inversion recovery sequence (FLAIR) imaging. We suspected a paraneoplastic brainstem encephalitis because of his smoking history, rapidly progressive symptoms and abnormal brainstem signs. A positron emission tomography-CT scan identified abnormal subcarinal nodes, shown on biopsy to be metastatic small cell lung cancer. He is currently undergoing treatment with chemotherapy and radiotherapy.

Spontaneous Nosocomial Pseudomonas aeruginosa Meningitis Presenting as Trismus

We describe the case of a 78-year-old female receiving adjuvant postsurgical chemotherapy for colon adenocarcinoma who spontaneously developed nosocomial Pseudomonas meningitis causing severe trismus. The patient was initially admitted for ileus, developing neck stiffness and trismus on the thirteenth day of admission. Cerebrospinal fluid grew pansensitive Pseudomonas aeruginosa. Magnetic resonance imaging of the brain was consistent with bilateral subacute infarcts secondary to meningitis. The patient responded well to 21 days of broad spectrum antimicrobial therapy modified to ceftazidime alone following speciation and sensitivity. Outpatient follow-up at 46 days revealed normal maximal mouth opening with the ability to chew and tolerate a full diet. Trismus is a motor disturbance of the trigeminal nerve with difficulty in opening the mouth. Infectious etiologies commonly described include tetanus, odontogenic infections, or deep neck space infections. This is the first reported case of simultaneous nosocomial Pseudomonas meningitis and trismus in a patient with no history of neurosurgery or lumbar spinal manipulation.

Limited mouth opening after primary therapy of head and neck cancer

OBJECTIVES

Patients after surgery and radiation/chemoradiation for treatment of head and neck cancer often suffer from oral complications. These problems may be caused by surgery and radiation. Patients complain, for example, of swallowing problems and limited mouth opening (trismus).

METHODS

The maximal interincisal mouth opening (MIO) was measured in patients treated with surgery and radiation/chemoradiation for head and neck cancer at the Department of Otorhinolaryngology at the University of Rostock. These patients also completed a 20-item questionnaire concerning nutritional, sensual, and speech disorders and pain.

RESULTS

One hundred one patients (16 female and 85 male) returned the questionnaire and were included in the study. About 50% of the patients had a limited mouth opening (<36 mm); patients with oropharyngeal cancer had a significant higher risk for trismus (p = .024) than patients with other head and neck cancers, especially compared to patients with laryngeal cancer (p = .013). The questionnaire showed that especially patients with oral cancer report about problems with opening the mouth (73%), eating (65%), drinking (73%), xerostomia (92%), speech disorders (68%), and voice (62%). Patients with laryngeal cancer only reported about problems with xerostomia (62%), speech (83%), and voice (90%), similar to patients with pharyngeal cancer.

CONCLUSIONS

About half of the patients who underwent primary treatment for oral and oropharyngeal cancer developed trismus and reported about problems with opening the mouth, eating, drinking, dry mouth, voice, and speech. Trismus has a negative impact on quality of life and should be a focus in the postoperative management of patients with oral and oropharyngeal cancer, and, if diagnosed, special treatment should be initialized.

Early Use of a Mechanical Stretching Device to Improve Mandibular Mobility After Composite Resection: A Pilot Study

OBJECTIVE

To evaluate the use of a mechanical stretching device, the Therabite, for the early postoperative management of trismus in select patients.

DESIGN

Prospective series of consecutive head and neck cancer patients.

SETTING

Academic, tertiary referral center.

PARTICIPANTS

Seven patients with oropharyngeal carcinoma who underwent resection and radial forearm flap reconstruction. Five had midline mandibulotomy procedures for exposure. Six had radiation therapy (2 pre, 4 post).

INTERVENTIONS

Patients were given a Therabite mechanical jaw mobilization device, were instructed in its proper use, and began using it within 6 weeks postoperatively.

MAIN OUTCOME MEASURES

Maximal interincisor opening (MIO) was measured at the beginning of use and at the most recent postoperative visit. A 5-question self-assessment telephone survey was administered on study completion.

RESULTS

The average MIO was 30 mm (range, 21-38 mm) at the beginning of the study and 40 mm (range, 30-57 mm) at the last visit. Average gain in MIO was 10 mm (range, 1-21 mm). Four of 5 assessable patients had minimal or no limitation on overall quality of life relative to jaw opening. No complications were associated with use of the device. Two patients could not be located for follow-up.

CONCLUSIONS

The Therabite mechanical stretching device is effective and safe for the management of trismus in a select group of head and neck cancer patients after extensive ablation and complex reconstruction. Specifically, there were no adverse effects in the 5 patients who had undergone midline mandibulotomy.

Difficult tracheal intubation induced by maxillary distraction devices in craniosynostosis syndromes

BACKGROUND

Difficult intubation occurred during anaesthesia for removal of maxillary distraction devices in five of seven children with syndromal craniosynostoses (four with Apert, two with Pfeiffer and one with Crouzon syndrome).

METHODS

Intubation was assessed in terms of laryngeal view and an established intubation difficulty score and had been straightforward before device insertion. Difficulty was induced by trismus due to device insertion and by increased maxillary prominence. This was compounded by preexisting mandibular hypoplasia. Cephalometric analysis, with each child acting as their own control, demonstrated anterior displacement of the maxilla and increased maxillary vertical height, as well as increased protuberance of the maxillary incisors.

RESULTS

All five difficult tracheal intubations were associated with preoperative Mallampati scores of 3 or 4 and the nine straightforward intubations with scores of 1 or 2. Maximal interincisor distance was less than the lower 95% confidence limit for age in all five children who were difficult to intubate at the time of device removal. No child had a failed intubation, but all had significantly increased intubation difficulty.

CONCLUSIONS

In view of the risks of trauma, hypoxia and aspiration associated with difficult direct laryngoscopy, we recommend elective fibreoptic intubation at anaesthesia for removal of maxillary distraction osteogenesis devices in these children.

Trismus in patients with malignant tumours in the head and neck

In order to elucidate the causal mechanism of trismus in head and neck cancer, 21 patients manifesting trismus out of 212 patients with malignant tumours in the head and neck (treated in Tokyo University Branch Hospital from 1983 to 1991) were reviewed. Nine patients developed trismus either by infiltration of the muscles of mastication or by reflex spasm. Trismus was considered to have developed as a result of irradiation in five cases and of surgical intervention in seven cases. In some cases of oropharyngeal cancer, CT revealed no evidence of tumour invasion into the infratemporal fossa when trismus occurred, suggesting that trismus was caused either by the reflex spasm of muscles or by microinvasion too small to be seen in CT films. Maxillary sinus tumours were often without trismus even when they extended posteriorly to the infratemporal fossa.