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Year : 2016  |  Volume : 12  |  Issue : 2  |  Page : 685-688

Trismus in head and neck cancer patients treated by telecobalt and effect of early rehabilitation measures

Department of Radiotherapy, Victoria Hospital, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India

Date of Web Publication25-Jul-2016

Correspondence Address:
S Amrut Kadam
H Block, Department of Radiotherapy, Victoria Hospital, Bangalore Medical College and Research Institute, K R Road, Bengaluru - 560 002, Karnataka
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/0973-1482.176181

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 > Abstract 

Context: Trismus is one of the common late side effects of radiotherapy (RT) of head and neck cancers. It occurs in about 30% of patients treated by telecobalt. It, in turn, leads to significant morbidity, including malnutrition, difficulty in speaking, and compromised oral hygiene with severe psychosocial, and economic impacts.
Aims: To determine the prevalence of trismus and its progression in patients who have received radical concurrent chemoradiation for head and neck cancer by telecobalt at our institution. To note the effect of early rehabilitative measures on the severity of trismus and to assess its impact on the quality of life (QOL).
Subjects and Methods: A total of 47 evaluable patients of head and neck cancer patients treated by telecobalt with radical intent between January 2012 and December 2013 were analyzed and baseline maximal inter-incisal opening (MIO) and MIO at the completion of RT, after 3 months, 6 months, and 1 year, after completion of RT were noted. Grading of trismus was done using Modified Common Toxicity Criteria (CTCAE Version 3.0). QOL assessment was done using European Organization for Research and Treatment of Cancer QLQ-HN35. The time when the rehabilitative measures were started were also noted.
Statistical Analysis Used: Chi-square test with Fisher exact probability test and Students t-test.
Results: Radiation-induced trismus (RIT) was seen in 31.9%, 34.04%, and 38.39% of cases at 3, 6, and 12 months after completion of RT. Grade II and III trismus accounted for 17.02% and 6.38% at the end of 1 year. Patients who started regular rehabilitative exercises soon, after completion of RT had a better mean MIO as compared to those who were not compliant (32 mm vs. 24 mm at 1 year), and there was a trend toward delayed progression in them. Trismus was also seen to adversely affect QOL of the patients.
Conclusions: RIT is a major cause for late morbidity in patients treated with conventional RT leading to poor QOL. Early rehabilitative measures are useful in preventing progression of trismus.

Keywords: Maximal inter-incisal opening, radiation-induced trismus, rehabilitative measures, telecobalt

How to cite this article:
Nagaraja S, Kadam S A, Selvaraj K, Ahmed I, Javarappa R. Trismus in head and neck cancer patients treated by telecobalt and effect of early rehabilitation measures. J Can Res Ther 2016;12:685-8

How to cite this URL:
Nagaraja S, Kadam S A, Selvaraj K, Ahmed I, Javarappa R. Trismus in head and neck cancer patients treated by telecobalt and effect of early rehabilitation measures. J Can Res Ther [serial online] 2016 [cited 2023 Jan 27];12:685-8. Available from: https://www.cancerjournal.net/text.asp?2016/12/2/685/176181

 > Introduction Top

Radiotherapy (RT) plays a major role in the multidisciplinary management of head and neck squamous cell carcinoma (HNSCC). One of the common late toxicities of RT is trismus,[1] which seriously affects the nutrition and quality of life (QOL) of the patients.[2] It can lead to difficulty in chewing, decreased oral intake, poor oral hygiene, speech impairment, and disturbed social interaction that can have significant physical, psychosocial and economic impact.[3],[4] As the life expectancy of these patients has improved over the years, the focus is slowly shifting to improving the QOL after treatment.[1]

Radiation-induced trismus (RIT) is restricted mouth opening with maximal inter-incisal opening (MIO) of <35 mm [5],[6],[7] as shown in [Figure 1]. It is due to a combined effect of fibrosis, spasm, and contracture of the muscles of mastication, and muscles responsible for the movement of the temporomandibular joint (TMJ) which include pterygoids [8] (medial, lateral), temporalis, and masseter. Other structures such as nerves, supportive tissue, and the TMJ are also affected by radiation resulting in limitation of mouth opening due to fibrosis and nerve entrapment.[1],[9] Risk factors for RIT include tumor location, higher RT dose,[10] larger volume of irradiation, and poor physical function of the patient.[9]
Figure 1: Trismus with maximal inter-incisal opening <35 mm

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Radiation delivery technique is another major factor in determining the incidence of RIT. A systematic review of the literature on RIT showed a mean incidence of 25% in patients treated with conventional technique compared with 5% with newer techniques such as intensity-modulated radiation therapy,[11],[12] which minimize the dose to the TMJ and muscles of mastication. A dose of more than 55 Gray (Gy) to the muscles of mastication is known to cause an incidence of trismus of up to 47%.[9]

Early rehabilitative measures seem helpful in reducing the extent and severity of various functional adverse effects of concurrent chemoradiation (CRT).[13],[14],[15],[16] Even with the advent of newer RT techniques in India, the majority of HNC patients are still treated with two-dimensional conventional RT using Co60 teletherapy unit due to cost and accessibility reasons. Hence, in this retrospective study, we have assessed trismus in such patients and studied the effect of early rehabilitative measures on trismus at our institute.

 > Subjects and Methods Top

Between January 2012 and December 2013, 128 patients with HNC were treated at our institute. Out of these, 47 patients with KPS >70 and baseline MIO >35 mm, who were treated radically (66–70 Gy in 2 Gy/fraction over 6–7 weeks) by telecobalt along with concurrent cisplatin were included in the study. Radiation was delivered using parallel opposed bilateral fields with spinal cord sparing after 46 Gy. Patients were immobilized using thermoplastic mask and shoulder retractor.

All patients were advised to start the below rehabilitative measures immediately post-RT thrice daily:

  1. Jaw exercises: Mouth opening against resistance with the hand under the jaw, sideway movement, jaw protrusion and retraction done 20 times at each session, 3 sessions per day
  2. Ice cream sticks: Inserting maximum sticks possible and kept in situ for a count of 25, increase it by 1–2 in the subsequent weeks.

MIO assessed at the completion of RT and 3, 6, and 12 months post-RT and compared to the baseline MIO. Grading of trismus was done using NCI Common Terminology Criteria for Adverse Events v3.0.

QOL assessment made for every patient using European Organization for Research and Treatment of Cancer QOL questionnaire head and neck cancer module (EORTC QLQ-HN35) at the end of 1 year. This assessment has seven multi-item scales (pain, swallowing, senses, speech, social eating, social contact, and sexuality). Eleven single-item scales (teeth, opening the mouth, dry mouth, sticky saliva, coughing, feeling ill, use of analgesics, nutritional supplement, feeding tube, weight loss, and weight gain) with lower scores signifying better QOL.

Statistical analysis

Descriptive statistics was to analyze frequency (age, gender, occupation, tobacco chewing habits, cancer stage, cancer subsite, performance status, and the adherence to rehabilitative measures) and mean (age, MIO at the various time interval and QOL scores). Chi-square test with Fisher exact probability test was used to analyse the prevalence of RIT in patients for compliance with rehabilitative measures. Student's t-test was used to compare the means of independent samples of MIO at different follow-up periods and also the difference in the QOL scores at 1 year in patients with or without trismus. The P < 0.05 is considered significant.

 > Results Top

Forty-seven nonmetastatic HNSCC patients were retrospectively analyzed with a mean age of 58 years, mean KPS of 80, and males constituting 81%. About 65% of the patients had the history of tobacco smoking, and 52% had the habit of chewing betel nut and tobacco. Oropharyngeal cancers constituted up to 36% of cases and 32% of the cases presented with stage IV A as seen in [Table 1].
Table 1: Patient demographics

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All patients received radical CRT with a mean dose of 6761.7 centigrays (standard deviation = 184.8 cGy). About 68%, 22%, 7%, and 3% of patients completed 5, 4, 3, and 2 cycles of concurrent cisplatin, respectively. Baseline means MIO pre-RT was 37.3 mm, which reduced progressively post- RT by 6 months and 1 year to 33.2 (P = 0.06) and 31.8 mm (P = 0.05) as depicted in [Figure 2].
Figure 2: Graph of percentage of trismus vs months post-RT

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RIT was seen in 31.9%, 34.04%, and 38.39% of HNSCC cases at 3, 6, and 12 months, respectively. Grade II and III trismus accounted for 17.02% and 6.38% at the end of 1 year. The patients on rehabilitative exercises on completion of RT had a mean MIO of 35 mm at 1 year versus a mean of 29 mm, who were not compliant to regular exercises with a risk ratio of 5.09 and odds ratio of 7.42 (P = 0.04).

Trismus significantly affects the QOL of patients with mean EORTC QLQ-HN35 scores in patients with Grade II and III trismus at the end of 1 year were 96.4 and 114.3, respectively, as compared to 44.1 in patients with no trismus (P < 0.001) [Figure 3]. The areas more adversely affected included social eating and contact (P < 0.05), teeth (P < 0.05), mouth opening (P < 0.001), pain (P = 0.05), dry mouth (P = 0.06), swallowing (P = 0.06), feeling ill (P < 0.05), use of analgesics (P = 0.04), and weight loss (P = 0.07).
Figure 3: Graph of QOL score vs grades of trismus (Lower score better QOL)

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 > Discussion Top

The pre-RT baseline MIO in our study was 37.3 mm, at the end of RT-35.4 mm and on follow-up of 3, 6, and 12 months was 34.9 mm, 33.2 mm, and 31.8 mm, respectively. The post-RT occurrence of trismus at the end of 3, 6, and 12 months was found to be 31.9%, 34.04%, and 38.39%, respectively. Lee et al. with the same definition of trismus (MIO ≤ 35 mm), reported RIT incidence rate of up to 42% that is comparable to the occurrence in our study.[4] The progression of trismus slows down from 6 months to 1 year as shown by Wang et al.[17]

Early rehabilitative measures started while on RT or post-RT showed improved mouth opening as compared to patients who were noncompliant to rehabilitative exercises or started it after initial fibrosis of muscles of mastication and TMJ had set in. The mean MIO was 35 mm in patients following early rehabilitative measures as compared with 29 mm in patients who started with mouth opening exercises later. These results were similar to results documented by Bensadoun et al. and Lisette et al. that the early treatment of trismus had the potential to prevent or minimize the progression of trismus and thereby improving the QOL.[1],[15]

All the patients received radical CRT by bilateral portals with the mean dose of 67 Gy to the masticator apparatus and TMJ. The dose-response was similar to the results by Kent et al. who reported a mean MIO of 28 mm with a dose of >55 Gy.

In a prospective study of 43 nasopharyngeal cancer by Tang et al.,[14] the pre-RT and post-RT inter-incisor distance (IID) was similar in the rehabilitation group compared to baseline, while in the control group, IID significantly decreased. Although the mean IID in patients of both groups decreased after the 3-month follow-up, the decrease in the rehabilitation group was less than that of the control group that further supports our observation that early rehabilitative measures reduce the progression of trismus.

Higher grades of trismus had higher scores in EORTC 35 QOL questionnaire hence, poor QOL. In this study, patients with grade 3 trismus had significantly higher mean score of 114 as compared to 44 in patients with no trismus. Grade 1 and 2 trismus patients had intermediate scores of 55 and 96, respectively. They had higher scores for pain in mouth and jaw, difficulty in taking solid food, and tended to consume pureed food and had trouble in eating in public. Collectively, trismus had both physical and psychosocial impact on the patient. Lee et al. and Pauli et al. also concluded that RIT negatively impacted QOL.[3],[4]

Considering the high prevalence of trismus in published studies in patients treated with the conventional planning of RT and QOL deficits associated with trismus, increased efforts for patient education and counseling regarding early and regular mouth opening exercises are warranted.

Hence, the routine practice of rehabilitative exercises is advocated in patients receiving RT to head and neck. However, further prospective studies on the effect of early rehabilitative measures with the larger number of patients are necessary. Sharing of more data is essential to address this issue as the telecobalt treatment is becoming less popular in the country.

 > Conclusions Top

RIT is a major cause of late morbidity in patients treated with conventional RT leading to poor QOL. Early rehabilitative measures are useful in preventing trismus and may improve QOL of patients.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

 > References Top

Bensadoun RJ, Riesenbeck D, Lockhart PB, Elting LS, Spijkervet FK, Brennan MT; Trismus Section, et al. A systematic review of trismus induced by cancer therapies in head and neck cancer patients. Support Care Cancer 2010;18:1033-8.  Back to cited text no. 1
Bhandare N, Mendenhall WM. A literature review of late complications of radiation therapy for head and neck cancers: Incidence and dose response. J Nucl Med Radiat Ther 2012;S2:009.  Back to cited text no. 2
Pauli N, Johnson J, Finizia C, Andréll P. The incidence of trismus and long-term impact on health-related quality of life in patients with head and neck cancer. Acta Oncol 2013;52:1137-45.  Back to cited text no. 3
Lee LY, Chen SC, Chen WC, Huang BS, Lin CY. Postradiation trismus and its impact on quality of life in patients with head and neck cancer. Oral Surg Oral Med Oral Pathol Oral Radiol 2015;119:187-95.  Back to cited text no. 4
Dijkstra PU, Huisman PM, Roodenburg JL. Criteria for trismus in head and neck oncology. Int J Oral Maxillofac Surg 2006;35:337-42.  Back to cited text no. 5
Johnson J, Carlsson S, Johansson M, Pauli N, Rydén A, Fagerberg-Mohlin B, et al. Development and validation of the Gothenburg Trismus Questionnaire (GTQ). Oral Oncol 2012;48:730-6.  Back to cited text no. 6
Scott B, Butterworth C, Lowe D, Rogers SN. Factors associated with restricted mouth opening and its relationship to health-related quality of life in patients attending a maxillofacial oncology clinic. Oral Oncol 2008;44:430-8.  Back to cited text no. 7
Goldstein M, Maxymiw WG, Cummings BJ, Wood RE. The effects of antitumor irradiation on mandibular opening and mobility: A prospective study of 58 patients. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1999;88:365-73.  Back to cited text no. 8
Louise Kent M, Brennan MT, Noll JL, Fox PC, Burri SH, Hunter JC, et al. Radiation-induced trismus in head and neck cancer patients. Support Care Cancer 2008;16:305-9.  Back to cited text no. 9
Teguh DN, Levendag PC, Voet P, van der Est H, Noever I, de Kruijf W, et al. Trismus in patients with oropharyngeal cancer: Relationship with dose in structures of mastication apparatus. Head Neck 2008;30:622-30.  Back to cited text no. 10
van der Molen L, Heemsbergen WD, de Jong R, van Rossum MA, Smeele LE, Rasch CR, et al. Dysphagia and trismus after concomitant chemo-Intensity-modulated radiation therapy (chemo-IMRT) in advanced head and neck cancer; dose-effect relationships for swallowing and mastication structures. Radiother Oncol 2013;106:364-9.  Back to cited text no. 11
Chen YY, Zhao C, Wang J, Ma HL, Lai SZ, Liu Y, et al. Intensity-modulated radiation therapy reduces radiation-induced trismus in patients with nasopharyngeal carcinoma: A prospective study with>5 years of follow-up. Cancer 2011;117:2910-6.  Back to cited text no. 12
Vissink A, Burlage FR, Spijkervet FK, Jansma J, Coppes RP. Prevention and treatment of the consequences of head and neck radiotherapy. Crit Rev Oral Biol Med 2003;14:213-25.  Back to cited text no. 13
Tang Y, Shen Q, Wang Y, Lu K, Wang Y, Peng Y. A randomized prospective study of rehabilitation therapy in the treatment of radiation-induced dysphagia and trismus. Strahlenther Onkol 2011;187:39-44.  Back to cited text no. 14
van der Molen L, van Rossum MA, Burkhead LM, Smeele LE, Rasch CR, Hilgers FJ. A randomized preventive rehabilitation trial in advanced head and neck cancer patients treated with chemoradiotherapy: Feasibility, compliance, and short-term effects. Dysphagia 2011;26:155-70.  Back to cited text no. 15
Li XH, Liao YP, Tang JT, Zhou JM, Wang GH. Effect of early rehabilitation training on radiation-induced trismus in nasopharyngeal carcinoma patients. Ai Zheng 2007;26:987-90.  Back to cited text no. 16
Wang CJ, Huang EY, Hsu HC, Chen HC, Fang FM, Hsiung CY. The degree and time-course assessment of radiation-induced trismus occurring after radiotherapy for nasopharyngeal cancer. Laryngoscope 2005;115:1458-60.  Back to cited text no. 17


  [Figure 1], [Figure 2], [Figure 3]

  [Table 1]

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