Temporomandibular joint dysfunction following tonsillectomy

S. MAINI,� J.E. OSBORNE,� H.M.S. FADL,� C. SPYRIDAKOU,� L.OGUNYEMI�

& P. HILLyDepartments of �Otolaryngology and yMedical Physics, Glan Clywd Hospital, Bodelwyddan, North Wales, UK

Accepted for publication 30 October 2001

M A I N I S . , O S B O R N E J .E . , FA D L H.M.S . , S P Y R I DA KO U C. , O G U N Y E M I L. & H I L L P.

(2002) Clin. Otolaryngol. 27, 57–60

Temporomandibular joint dysfunction following tonsillectomy

We report a prospective, controlled trial to assess temporomandibular joint (TMJ) dysfunction following the

use of a Boyle–Davis mouth gag during tonsillectomy. TMJ function was evaluated in patients undergoing

tonsillectomy and a control group undergoing nasal surgery preoperatively and 6 weeks postoperatively.

The main outcome measures were symptoms and signs of TMJ dysfunction and interincisal distance. A mean

reduction of 0.89 mm in interincisal distance (P< 0.01) was noted postoperatively in the tonsillectomy

patients. There was no statistically significant reduction of interincisal distance in patients undergoing nasal

surgery. There was a statistically significant reduction in interincisal distance in the post-tonsillectomy

patients, caused by fibrous healing of the tonsillar bed or fibrous ankylosis of the TMJ.

Keywords tonsillectomy temporomandibular dysfunction (TMJ) interincisal complications fibrosis

Tonsillectomy remains a common surgical procedure in

otolaryngology. The literature mentions that insertion of a

Boyle–Davis mouth gag during tonsillectomy can lead to

dislocation of the TMJ or pain as a result of postoperative

joint dysfunction.1 The common causes of TMJ dysfunction

include arthritis of the TMJ, arthritis from mandibular over-

closure or displacement, dental problems, accidents, stress-

related masseter muscle tension and general anaesthesia.

There is a significant association between trauma and TMJ

dysfunction2 and a less favourable outcome is associated with

post-injury TMJ disorders.3 Our clinical impression is that

temporary dislocation of the TMJ occasionally occurs during

tonsillectomy. Difficulty in opening the mouth wide is also

reported by patients following surgery. On literature

review, the incidence of TMJ disorders following the use of

Boyle–Davis mouth gag during tonsillectomy had never been

studied.

Patients and methods

A total of 56 patients undergoing tonsillectomy or nasal

surgery (control group) in Glan Clywd Hospital from August

2000 to March 2001 were enrolled in a prospective single-

blind, controlled trial approved by the local ethical committee.

Exclusion criteria included patients undergoing non-routine

surgery, any other surgery in addition to tonsillectomy, pre-

operative TMJ dysfunction, rheumatoid arthritis, age less than

5 years or more than 40 years and patients lost to follow-up.

The information sheet given to patients participating in the

study did not indicate the special interest of the study in post-

tonsillectomy patients or the topic of the study, therefore,

reducing the bias in the tonsillectomy group. After informed

consent, patients completed a questionnaire related to TMJ

function (see Appendix). History-taking and examination of

TMJ function was performed by a doctor blinded as to which

arm of the study the patient belonged. Interincisal distance

was measured preoperatively with a Willis gauge (Figs 1 and

2). The anaesthetic techniques in both groups were individual,

however, all patients underwent surgery under general anaes-

thesia with endotracheal intubation.

A total of 27 patients (7 males and 20 females) undergoing

tonsillectomy, and 25 patients (14 males and 11 females)

undergoing nasal surgery, were included in the study. Three

Clin. Otolaryngol. 2002, 27, 57–60

# 2002 Blackwell Science Ltd 57

Correspondence: Ms Sangeeta Maini, Specialist Registrar ORL-H &N Surgery, Royal Gloucestershire Hospital, Gloucester GL13NN,UK (e-mail: sangeetamaini@hotmail.com).Presented at the Joint meeting of the American Academy ofOtolaryngology Head and Neck Surgery and of the PanhelenicSociety of Otorhinolaryngology Head and Neck Surgery, Athens,Greece, in June 2001.

patients in the tonsillectomy group and one patient in the nasal

surgery group were excluded as they were lost on follow-up.

The patients’ ages in the tonsillectomy group ranged from 14

to 45 years (mean age was 22.7 years) and in the control group

ranged from 19 to 45 years (mean age 31.7 years). Patients

were followed up 6 weeks postoperatively in the ENT OPD by

a surgeon who, after the consultation, then referred the

patients to a different doctor (HF or CS) unaware of the

surgery the patient had undergone. Postoperative clinical

TMJ assessment and measurement of interincisal distance

was carried out. The results were analysed using the paired

t-test, having assessed the appropriateness of Gaussian para-

metric statistics.

Results

In our study, three out of 27 post-tonsillectomy patients

mentioned TMJ symptoms (TMJ clicking, TMJ pain, masti-

catory pain) lasting a few days postoperatively. This was not

persistent 6 weeks later. As TMJ dysfunction assessment

immediately post operation was not a part of the study, it

is possible that a larger number had short-term TMJ dysfunc-

tion. Eleven out of 27 patients in the tonsillectomy group had

reduced interincisal distance 6 weeks postoperatively. In the

tonsillectomy group, the mean preoperative interincisal dis-

tance was 45.1 mm (range 35–55 mm) and mean postoperative

interincisal distance was 44.2 mm (range 33–55 mm). There

was, therefore, a significant reduction in interincisal distance

postoperatively in the tonsillectomy group P< 0.01 (paired t-

test). The mean reduction is 0.89 mm compared with the

control group in which there was no statistically significant

reduction in interincisal distance (Figs 3 and 4).

Discussion

Normal adult mouth opening ranges between 23 and 71 mm

measured between the incisor teeth. The maximal interincisal

distance, i.e. linear mouth opening, is generally used as a

measure for TMJ mobility and is significantly related to

condylar mobility.4 The muscles of mouth closure, which

consist of the temporalis, masseter and medial pterygoid

muscles, exert a power 10 times greater than the opening

Figure 1. Willis gauge. Figure 2. Use of Willis gauge to measure interincisal distance.

58 S. Maini et al.

# 2002 Blackwell Science Ltd, Clinical Otolaryngology, 27, 57–60

muscles, consisting of the lateral pterygoid, digastric, mylo-

hyoid, geniohyoid and the lower hyoid muscles. This explains

the existence of trismus in patients with generalized muscle

spasms, for example, tetanus.5 The pathogenesis of trismus in

peritonsillar abscess has not been completely elucidated, but

inflammation of the soft palate and peritonsillar tissue prob-

ably induces sensory impulses by reflex producing bilateral

increased tonus of muscles of mastication.6

Throat pain, ear pain and trismus immediately following

tonsillectomy are as a result of inflammation, nerve irritation

and spasm of the exposed pharyngeal muscles. The symptoms

do not completely subside until the muscles become covered

with mucosa 14–20 days after surgery.7 Several factors

affect the degree of acute inflammation in the tonsillar bed

following tonsillectomy. The technique of minimal and pre-

cise dissection confined to natural planes along with minimal

use of electrocautery may reduce post-tonsillectomy inflam-

matory reaction. Substantial tissue destruction can result in

healing of the tonsillar bed by fibrosis and resultant reduced

mouth opening. As the goal of our study was to assess TMJ

Figure 3. Postoperative change in interincisor distance (IID) versus preoperative value: tonsillectomy group.

Figure 4. Postoperative change in interincisor distance (IID) versus preoperative value: control group.

# 2002 Blackwell Science Ltd, Clinical Otolaryngology, 27, 57–60

TMJ dysfunction following tonsillectomy 59

dysfunction, we arranged a 6-week postoperative follow-up to

allow the raw areas of exposed muscles of oropharynx to heal

completely. The reason to choose patients undergoing nasal

surgery as the control group was to exclude the confounding

factor of TMJ trauma during endotracheal intubation during

general anaesthesia.

Even a mild injury, such as a contusion of the soft tissues of

the TMJ following trivial trauma, is usually sufficient to cause

oedema of the posterior, loose part of the disk and of the

capsule, as well as synovitis and sometimes a serous effusion.

Traumatic injuries may be followed by cicatrical contractions,

adhesions and even fibrous ankylosis of the joint.8 Thus,

fibrous ankylosis of the TMJ following trauma, inflammation

or prolonged immobilization may compromise the normal

movement of the mandible.9

The mean reduction in interincisal distance 6 weeks post-

operatively in the tonsillectomy patients noted in our study

may be as a result of healing by fibrosis of the tonsillar bed

and/or fibrous ankylosis of the TMJ.

Conclusions

We conclude that precise tissue dissection, combined with

gentle, not excessive, mouth opening with the Boyle–Davis

mouth gag intraoperatively, will be likely to reduce the post-

tonsillectomy difficulty in eating.

References

1 STELL P.M. (ed.) (1987) Acute infection of the pharynx andtonsils. In Scott Brown’s Otolaryngology, 5th edn. Laryngology,pp. 74–118. Butterworth, London

2 PULLINGER A.G., MONTIERO A. & LUI S. (1985) Etiologicalfactors associated with temporomandibular disorders. J. Dent.Res., 64 269, 848(Abstract)

3 BROOK R.I. & STEN P.G. (1978) Postinjury myofascial paindysfunction syndrome, its etiology and prognosis. J. Oral Surg.45, 846–850

4 DIJKSTRA P.U., DE BONT L.G., STEGENGA B. et al. (1995)Temporomandibular joint mobility assessment: a comparisonbetween four methods. J. Oral Rehabilit. 22 (6), 439–444

5 BEEKHIUS G.J. & HARRINGTON E.B. (1965) Trismus. Etiologyand management of inability to open the mouth. Laryngoscope75, 1234–1258

6 MERCURI L.G. (1981) The Hecht, Beals and Wilson Syndrome:report of a case. J. Oral Surg. 39, 53–56

7 COTRAN R.S., KUMAR V. & ROBBINS S.L. (1994) Inflammationand Repair. In Pathologic Basis of Disease, 5th edn, pp. 51–92.W. B. Saunders, Philadelphia

8 Temporomandibular joint problems. Radiology of the Tempor-omandibular joint. Proceedings of the 1st International Sympo-sium, Newport Beach, California, pp. 49–64

9 TVETERAS K. & KRISTENSEN S. (1986) The aetiology andpathogenesis of trismus. Clin. Otolaryngol. 11, 383–387

Appendix. Questionnaire and Assessment Sheet

Preop 6/52 Postop

Left Right Left Right

Pain over TM jointPain on chewingLimitation in mouth openingJaw noise (clicking or grinding)Locking of jaw

Yes No

Do you grind your teeth?Do you have arthritis (present or past)?

Preop Postop 6/52

Right Left Right Left

Mouth opening (mm)TM joint tendernessTenderness over masticatory musclesTM joint crepitusTM joint clickingTM joint incoordinationAny other

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60 S. Maini et al.