Dental — 30 November 2020 at 5:44 pm

AM Guide to Managing Jaw Dislocation on Expedition

Burjor Langdana / Adventure Medic Resident Expedition Dentist / Founder Wilderness Expedition Dentistry

Matt Edwards / Emergency Medicine Consultant / Air Ambulance Kent Surrey Sussex / Contributor Wilderness Expedition Dentistry

 

This article is the sixth of our series and aims to provide you with some guidelines on managing acute non-traumatic temporomandibular joint (TMJ) dislocation in the field. For more in the series, check out the Adventure Medic Dental page.

Background

Most medics will have had little experience with TMJ dislocation, which only represents 3% of all joint dislocations.1 While it is not uncommon for these to be relocated under sedation or anaesthesia, they are very treatable without sedation, especially if attempted early.2 Therefore, all expedition medics should be comfortable to assess, diagnose and manage a dislocated temporomandibular joint.

 

There is a shriek around the campfire. “She can’t close her mouth!” You rush over, finding this frightened young woman in acute pain. She has saliva drooling from her mouth. Her mouth appears to be locked open. You are in the middle of nowhere. There is no access to anaesthesia or sedation. What can you do?

 

This article and slideshow aim to:

  1. Describe how to diagnose acute temporomandibular joint (TMJ) dislocation.
  2. Demonstrate the various treatment options, with a stepwise escalation for when treatment options fail.
  3. Describe the considerations and management of prolonged dislocation.

Diagnosis

The Patient

  1. Acute Pain (especially anterior to the ear) due to major myospasm associated with the dislocated joint.
  2. Difficulty in speaking due to the inability to open or close mouth. Give them a means to write so they can tell you how it happened.
  3. Excess salivation as they may find swallowing impossible. This will make taking any oral medication difficult.
  4. No difficulty in breathing or stridor. If this is the case, consider alternative diagnosis such as retropharyngeal swelling and/or infection.

What you see

  1. Normally the jaw is displaced anteriorly with bilateral dislocations. The mouth will be held open, lower jaw appears prominent with midline maintained.
  2. Occasionally dislocation could be unilateral and the midline of the jaw will deviate to the side opposite to the dislocation i.e. to the normal side. Look at the relationship of the upper and lower incisors as a reference point.
  3. Rarely, dislocations can occur posteriorly, laterally or even superiorly. 3,4,5 This tends to be more common with trauma and can be more easily missed.
  4. You should not see neck swelling or haematomas under the tongue.

What you feel

  1. Hollowing in front of the tragus.
  2. You should not feel any crepitus or instability of the jaw or swelling in the neck.

Why did this happen?

Wide-open mouth (yawning, eating, laughing, singing) and an underlying susceptibility. It is even possible during routine dental checks!

  • Condyle (The rounded projection of the lower jaw that fits into the fossa of the temporal bone) moves onto the articular eminence (the raised area of bone at the anterior limit of the temporal fossa)
  • Condyle slips forward, preventing the mouth from closing
  • Powerful masticatory muscles tighten/spasm
  • These biting muscles easily overpower the weaker mouth opening muscles
  • The mandible is then held in this new ‘open and protruded’ position
  • Causes a reinforcing cycle and muscles contract further
  • The mandible becomes ‘locked’ in this position.

 

Dislocations and fracture-dislocations can occasionally occur with trauma 5 and in these cases, it is important to ensure:

  • The airway is not compromised
  • C-spine injury is considered
  • Tooth avulsions are located (if they cannot be found, assume they are in the right main bronchus)
  • Tooth avulsions are relocated (see the AM Guide to Dental Trauma)
  • Mandibular fractures are considered (look for gum-line bleeding, sublingual haematoma)
  • External auditory meatus is examined for bleeding or occlusion (posterior fracture/dislocations) 3
  • Mastoid area is examined for bruising (Battle Sign) – basilar skull fracture due to posterior dislocation) 16

It is likely these patients with traumatic dislocation/fracture-dislocation will require medevac and operative reduction. The techniques described below are not suitable for these types of dislocations.

 

What can you do?

Relocation options:

1. Hippocratic 6 / Traditional intraoral method 7

a) Reposition mandible both sides at the same time

  1. Seat patient lower than you
  2. Place your thumb inside the mouth. Your thumb will rest on the top (occlusal surface) of the lower molar teeth
  3. Your remaining fingers are outside the mouth. They will extend along the lower border of the mandible from angle to chin
  4. Exert downward, steady, constant pressure on patients’ lower molars with your thumb while the remainder of your fingers and hand around chin are levering upwards
  5. As myospasm is overcome you will feel a give sensation
  6. Then guide the mandible posteriorly and upwards

b) Reposition mandible one side at a time 8

  1. Fix the patients head between your body and non-dominant hand
  2. Place the thumb of your dominant hand onto the occlusal surface of the last molar of the side of the jaw to be repositioned
  3. Grip the mandible with the rest of your hand
  4. Apply gentle but increasing downward pressure
  5. Gradually increase the force for up to five minutes until you feel the condyle move
  6. Guide upwards and backwards very slightly until you feel condyle slide into fossa.
  7. After reducing one TMJ, hold it in position with your non-dominant hand by positioning a finger in front of the reduced condyle.
  8. Then reposition the other TMJ in the manner stated above.
How to avoid getting bitten
  • Instruct the patient that you will guide the jaw in its closed position and they should not contribute by attempting to bite
  • Gauze wrap around thumbs
  • Place thumb on bony ridge present on the cheek side of mandibular molars, rather than on the top surface of the molars
  • Consider using the Syringe Technique (see below)
  • Consider using the Extra Oral Technique (see below)

 

2. ‘Syringe’ or Lever Technique for reducing TMJ dislocation 9,10

This technique had a 97% success rate in one series when the patients presented within two hours of dislocation.9 It utilises the patient’s own strong masseter to pivot the jaw around a fulcrum pushing the mandibular condyle down and back into place.

  1. Choose the right size of syringe (5 to 10 ml) or similar sized rigid cylindrical-shaped item. Wide enough for the patient to rest/bite on in the dislocated position i.e. 2-3cm. This could even be a roll of gauze, as described in the ‘lever’ technique.
  2. Place it between the upper and lower molars on one side.
  3. Tell the patient to gently bite down.
  4. The patient is then encouraged to roll the syringe back and forth. By protruding mandible forwards and retruding it backwards. Gradually more and more movement will be tolerated.
  5. Simultaneously you assist by grasping the end of syringe protruding from the side of the mouth. And rotating it forwards and backwards.
  6. Syringe acts as a rolling fulcrum translating the force of the biting muscles to pivot the back of the jaw back into its socket.
  7. The opposite side reduces spontaneously. If this does not occur, the syringe should be placed on that side as well.

3. Extra-Oral Technique for reducing TMJ dislocation 11

  1. Patient in sitting or supine position
  2. You stand in front of the patient.
  3. You place your thumb on the patient’s cheek, on the coronoid process of the dislocated mandible. Your thumb then applies persistent posterior pressure. The rest of the fingers of this hand are placed behind this same mandible, posterior to the mastoid process, stabilising the grip.
  4. Simultaneously on the opposite side. You then place your thumb on the malar eminence (cheek prominence) and your fingers around the angle of the mandible. Applying an anterior force (Like jaw thrust manoeuvre.)
  5. Then, by pulling the mandible anteriorly and simultaneously using your other hand to push the coronoid posteriorly, the jaw rotates facilitating contralateral TMJ reduction.
  6. Once one side is reduced, the other side will usually go back spontaneously.
  7. If this does not work apply posterior force on both coronoid processes at the same time.

Problem-solving: prolonged dislocation

You have been away from the campsite. The dislocation is now 24 hours old and myospasm has set in. The traditional method of reduction is not working. You don’t have access to sedation or GA. What can you do?

 

In this scenario, you could try:

  • Ensure adequate analgesia. If possible, use IM medication as oral medications will be extremely difficult to swallow.
  • Ask the patient to open widely against resistance, through reciprocal inhibition, the muscle tone of the elevator muscles is reduced and then manual reduction can be attempted.
  • Syringe or Extra-Oral technique. It’s claimed that they have a higher success rate in the presence of excessive myospasm.
  • The Wrist Pivot Method (see below)
  • If available, attempting regional nerve blocks (see below)
  • If none of these methods succeed there will be no option but to arrange a medevac.

Wrist Pivot Method 12

  1. Grasp the mandible at the mentum with both thumbs
  2. Place your fingers on the inferior molars
  3. Apply upward force on thumb and downward pressure with fingers
  4. The forces should be applied bilaterally to avoid mandibular fracture.

Deep Temporal Nerve block 13,14

  1. You will need a 30 gauge needle to inject approximately 0.5 to 0.8 ml of 2% Lignocaine with 1;100,000 adrenaline
  2. Take your index finger run it on the top surface of the zygomatic arch anteriorly until the horizontal arch meets the vertical zygomatic process. This is the area of anterior temporalis muscle
  3. Insert the needle parallel horizontally to the index finger through the temporalis muscle to contact the bone ( greater wing of sphenoid)
  4. Aspirate and inject and wait at least two minutes

Masseteric Nerve block 13,14

  1. You will  use a 30 gauge needle to inject approximately 0.5 to 0.8 ml of 2% Lignocaine with 1;100,000 adrenaline
  2. Take your thumb and middle finger. Grasp the anterior and posterior border of the ramus of the mandible, extra-orally, visualising the width of the ramus with your index finger.
  3. Locate the zygomatic arch. Follow to a point midway between thumb and index finger.
  4. Slide index finger inferiorly until it reaches the mandibular notch.
  5. Insert needle posteriorly, hitting the neck of the condyle approximate depth 7-10 mm
  6. Aspirate and inject and wait at least two minutes.

Patient care post-reduction

  1. Verify normal bite/occlusion i.e. midline of upper and lower teeth match. The patient may feel that the bite is good but not exactly right. This is frequently just some residual swelling around the TMJ.
  2. Cool compress
  3. Barrel bandage (check slide show for method) The patient may find the use of a cervical spine collar helpful 15
  4. Liquid diet for 48 hours
  5. Soft iedt for subsequent seven days
  6. NSAID for three days
  7. Follow up with their dentist when they return home

References

1 Lovely FW, Copeland RA. Reduction eminoplasty for chronic recurrent luxation of the temporomandibular joint. J Can Dent Assoc. 1981;47:179–184.

2 Liddell A, Perez DE. Temporomandibular joint dislocation. Oral Maxillofac Surg Clin North Am. 2015 Feb;27(1):125-36.

3 Albilia, Weisleder, and Wolford. Technique for Posterior Condylar Dislocation. J Oral Maxillofac Surg 2018.

4 Srinath N et al. Superolateral dislocation of the intact mandibular condyle: report of a rare case with a review. Int. J. Oral Maxillofac. Surg. 2017; 46: 1424–1428

5 Akinbami BO. Evaluation of the mechanism and principles of management of temporomandibular joint dislocation. Systematic review of literature and a proposed new classification of temporomandibular joint dislocation. Head Face Med. 2011 Jun 15;7:10.

6 Forshaw RJ. Reduction of temporomandibular joint dislocation: an ancient technique that has stood the test of time. Br Dent J. 2015 Jul;218(12):691-3.

7 DeAngelis AF et al. Review article: Maxillofacial emergencies: dentoalveolar and temporomandibular joint trauma. Emerg Med Australas. 2014 Oct;26(5):439-45.

8 Shun TA et al. A case series of closed reduction for acute temporomandibular joint dislocation by a new approach. Eur J Emerg Med. 2006 Apr;13(2):72-5.

9 The “syringe” technique: a hands-free approach for the reduction of acute nontraumatic temporomandibular dislocations in the emergency department. (J Emerg Med. 2014 Dec;47(6):676-81. doi: 10.1016/j.jemermed.2014.06.050. Epub 2014 Sep 30.)

10 Yeşiloğlu N et al. The lever technique for the external reduction of temporomandibular joint dislocation. J Plast Reconstr Aesthet Surg. 2015 Jan;68(1):123-5.

11 Gonai S et al. Extraoral autoreduction of temporomandibular joint dislocation: a preliminary clinical study. Am J Emerg Med. 2015 Apr;33(4):588-9.

12 Refractory Temporomandibular Joint Dislocation – Reduction Using the Wrist Pivot Method. ( Clin Pract Cases Emerg Med. 2017 Nov; 1(4): 380–383)

13 Woodall CE et al. The use of intraoral local anaesthetic to aid reduction of acute temporomandibular joint dislocation. J Stomatol Oral Maxillofac Surg. 2019 Apr;120(2):152-153

14 Use of Masseteric and Deep Temporal Nerve Blocks for Reduction of Mandibular Dislocation. ( Anesth Prog. 2009 Spring; 56(1): 9–13.doi: 10.2344/0003-3006-56.1.9)

15 Jaisani MR et al. Use of Cervical Collar in Temporomandibular Dislocation. J. Maxillofac. Oral Surg. (Apr–June 2015) 14(2):470–471

16 https://www.reliasmedia.com/articles/4144-the-facial-trauma-patient-in-the-emergency-department-review-of-diagnosis-and-management-part-iii