Abstract
Background: There is conflicting evidence regarding communication between the two compartments of the equine temporomandibular joint (TMJ). Understanding the inter-relationship between TMJ compartments is critical for diagnostic and clinical management purposes.Objective: To determine the frequency of communication between the discotemporal joint (DTJ) and the discomandibular joint (DMJ) of the equine TMJ in horses free of overt disease.Study Design: A randomized, blinded, controlled cadaveric study.Methods: Equine cadaver heads (n = 20), with no reported history of potential TMJ disease, were collected and stored frozen until use. Horses were randomized to the treatment group, such that Group A horses (n = 10) underwent arthrocentesis of the left DTJ and the right DMJ compartments, while Group B (n = 10) underwent arthrocentesis of the left DMJ and the right DTJ compartments of the TMJ, for a total of 40 joints. Computed tomography (CT) imaging was performed before, and after, intra-articular injection of contrast media in each head. Two observers, blinded to the treatment group, independently interpreted CT images.Results: Communication between synovial compartments occurred in the left TMJ of two horses. Arthroscopic evaluation revealed that both horses had a perforation of the intra-articular disc in the region of the caudomedial fibrous expansion. Mild anterior displacement of the abnormal disc in the joint of one horse was demonstrated using magnetic resonance imaging (MRI).Main Limitations: Sample size, the use of owner provided animals' history, and frozen specimens.Conclusions: No physiological communication was present between the DTJ and the DMJ in the equine TMJ of the cases studied, regardless of which compartment underwent arthrocentesis. Two joints had pathological communications. These results suggest that diagnostic, and medical, treatment of intra-articular disease may be most effective when both joint compartments are injected. Furthermore, this study illustrates the value of contrast enhancement while imaging the equine TMJ.
Highlights
The equine temporomandibular joint (TMJ) is a diarthrodial joint separated by a bi-concave, fibrocartilaginous, intra-articular disc
The larger of the two joint compartments is bounded by the mandibular fossa of the zygomatic process of the temporal bone dorsally, and the disc ventrally, forming the discotemporal joint (DTJ) [1]
Heads were stored frozen until use. They were thawed by Abbreviations: TMJ, temporomandibular joint; DTJ, discotemporal joint; DMJ, discomandibular joint; CT, computed tomography; MRI, magnetic resonance imaging; OA, osteoarthritis; TMJ-OA, temporomandibular joint osteoarthritis
Summary
The equine temporomandibular joint (TMJ) is a diarthrodial joint separated by a bi-concave, fibrocartilaginous, intra-articular disc. The larger of the two joint compartments is bounded by the mandibular fossa of the zygomatic process of the temporal bone dorsally, and the disc ventrally, forming the discotemporal joint (DTJ) [1]. The smaller compartment is situated below the disc and dorsal to the condylar process of the mandible, forming the discomandibular joint (DMJ) [2, 3]. There is conflicting evidence as to whether there is communication between the two joint compartments. It has been reported that the two compartments do not communicate [2, 4,5,6]. There is conflicting evidence regarding communication between the two compartments of the equine temporomandibular joint (TMJ). Understanding the inter-relationship between TMJ compartments is critical for diagnostic and clinical management purposes
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
