Risk factors and management of dislocation following total prosthetic TMJ replacement
Mustafa E, Sidebottom A
Department of Oral and Maxillofacial Surgery, Queens Medical Centre, Nottingham
Patients with end stage degenerative, inflammatory or ankylotic TMJ disease can be treated successfully with a total prosthetic joint replacement. Little is known about the surgical factors predisposing to dislocation of the joint prosthesis or how to best manage this complication. We present our experience treating dislocated joint prostheses and describe the risk factors we have identified through a study of our case series.
102 patients (females = 86) underwent total prosthetic temporomandibular replacement joint at the Nottingham University Hospitals between March 2004 and January 2013. Five patients received the Biomet prosthesis; all other patients received the TMJ Concepts system.
The prosthetic joint dislocated intra-operatively in eleven patients, an overall incidence of 10.8%. All patients were placed on light orthodontic elastics for a week and instructed on the standard regimen of mouth opening exercises. Only one patient experienced a subsequent joint dislocation. The patient required further traction and Dysport injection (abobotulinum toxin A, Medicis, Scottsdale, AZ, USA) due to dystonia.
The incidence of dislocation among patients who underwent a coronoidectomy was much higher at 30% (n=3/10)
compared to 7.6% (n=7/92) in those who did not undergo a coronoidectomy.
Among patients who did not undergo a coronoidectomy (n=92) we looked at patients who presented with an anterior open bite on a high mandibular plane angle. The incidence in this patient group was 11.1% (n=2/18). Of the remaining patients the incidence of joint dislocation was 8.1% (n=6/74).
Joint dislocation is an uncommon complication following total prosthetic TMJ replacement and may be treated successfully with one week of guiding elastics. Patients who undergo a coronoidectomy are at the highest risk of dislocation. Subsequent dislocation after one week has only occurred once and required further traction and Dysport injection.
1. Saeed N, Hensher R, McLeod N et al. (2002) Reconstruction of the temporomandibular joint autogenous compared with alloplastic. British Journal of Oral & Maxillofacial Surgery 40:296-299.
2. Jones RH. Temporomandibular joint reconstruction with total alloplastic joint replacement. Aust Dent J. 2011 Mar;56(1):85-91.