A Murine Model for Septic Arthritis of the Temporomandibular Joint

PurposeThis study was designed to establish a murine model of hematogenously acquired bacterial arthritis of the temporomandibular joint (TMJ) to investigate the pathogenesis of this rare TMJ infection.Materials and MethodsOne hundred forty mice were inoculated intravenously with 3 different staphylococcal suspensions. They were sacrificed at intervals between 1 day and 2 months. Bacterial cultures were obtained from peripheral blood, liver, kidney, TMJs, knees, and interphalangeal joints. The TMJs were collected for histopathological examination.ResultsStaphylococcus aureus, isolated from the joint fluid of a patient with septic arthritis of the TMJ, was recovered from the liver, kidneys, knees, interphalangeal joints, and TMJs of several animals. Blood cultures were negative. Acute septic arthritis of the TMJs was confirmed in several animals as soon as 4 days after inoculation. Histopathology showed severe damage to chondrocytes and collagen fibers in the condyles and discs, leading to extensive degenerative changes. All cultures were negative, and there were no histopathologic changes in animals inoculated with bacteria from the other sources.ConclusionsA murine model for hematogenous septic arthritis of the TMJ was successfully developed with S. aureus isolated from a patient with a TMJ infection. The bacteria induced multiple organ and joint infections. Septic arthritis of the TMJ occurred in 21% of the animals inoculated. Onset was rapid. It produced extensive degenerative changes. The study confirms the need for prompt diagnosis and treatment of patients with septic arthritis. The model may prove to be very useful in the study of this rare infection.