Anterior dislocation of the mandible is a clinical scenario that is not infrequently encountered by the ED provider and requires prompt intervention. The classic technique for reduction of the mandible requires the provider to place his/her thumbs or fingers into the patient’s mouth along the lower molars and apply force inferiorly and posteriorly. However, this technique is fraught with difficulties and inefficiencies including the following:
- It requires a surprising amount of force.
- The patient usually has to be sedated, possibly under procedural sedation, which usurps valuable resources in a busy ED.
- The ED provider has to incur the risk of personal injury and possible disease transmission by placing their hands into one of the most bacteria-ridden surfaces on this earth: the human mouth.
Luckily, there is a better way! Dr. Chen et al. from the Department of Plastic and Reconstructive Surgery at Chang Gung University in Taiwan describe a simple, effective, and novel technique to reduce the anteriorly displaced mandible. 1 In their experience, no sedation was required for any of their cases.
Mechanics of a Mandible Dislocation
The crux of this technique rests upon the following observations:
- When the mandible is dislocated anteriorly, the coronoid process and anterior border of the ramus can be palpated easily over the cheek on the affected side (figure 1).
- By applying steady pressure on the cheek over the coronoid process and anterior aspect of the mandibular ramus, the mandible can be easily reduced.
- Note that when the mandible is in its resting position and no dislocation is present, the coronoid process and anterior border of the ramus are not palpable as they are located posterior to the body of the zygoma (figure 2).
Trick of the Trade: Extra-Oral Reduction Technique for Anterior Mandible Dislocation
- Place the patient in either sitting or supine position.
- The provider should stand in front of the patient.
- The provider places their thumb on the patient’s cheek, on the mandibular ramus and coronoid process of the dislocated mandible, and applies persistent pressure posteriorly (figure 3).
- The fingers are placed behind the angle of the mandible to stabilize the grip.
- At the same time on the opposite side, the provider places their fingers from the other hand on the angle of the mandible and pulls, applying anterior force (figure 4). Note that this maneuver causes further anterior dislocation of the ipsilateral TMJ, rotates the jaw, and facilitates contralateral TMJ reduction.
Once one side of the dislocation is reduced, the other side will usually go back spontaneously. If that doesn’t work, repeating the same maneuver with minimal force will usually result in success. Also consider applying posterior force on both coronoid processes at the same time if the above strategy doesn’t work.
Animation of technique
One-minute animation by Spencer Evans and Dr. Karl Preiksaitis
Patient video demonstration
(Videography by Josh Luftig)
Discussion
Prior to a recent literature review that was prompted by a failed TMJ reduction under procedural sedation using the classic technique, I had never heard of this technique. Since then, I’ve used the technique on a patient with recurrent anterior TMJ dislocations, and it worked beautifully requiring surprisingly little amount of force compared to the classical technique. This will be my first-line technique for anterior TMJ dislocation in the ED. I’m excited to share it and interested to hear feedback on how it works for you. Contact me on Twitter at @Kat04747!
Images in this article were taken directly from the Chen et al. reference below with permission from Dr. Chen. The patient in the video provided consent for use of this video for educational purposes.
Reference
- Chen Y, Chen C, Lin C, Chen Y. A safe and effective way for reduction of temporomandibular joint dislocation. Ann Plast Surg. 2007;58(1):105-108. [PubMed]