Incidence of temporomandibular joint changes after whiplash trauma: a prospective study using MR imaging.

OBJECTIVE The purpose of this study was to describe the incidence of temporomandibular joint (TMJ) changes after a well-defined whiplash trauma. SUBJECTS AND METHODS Sixty consecutively admitted patients with symptoms in the neck after rear-end traffic collisions underwent MR imaging of the TMJs within 3-14 days after the collisions. Fifty-three healthy volunteers constituted a control group. RESULTS No statistically significant differences were found between the 60 patients and the 53 volunteers regarding frequency, stage, grade, or direction of TMJ disk displacement or joint effusion. MR imaging revealed that 45% of the control group and 53% of the patient group had a displaced disk in one or both TMJs (p = .393). Disk displacement was seen in 35% of TMJs in the control group and 40% of TMJs in the patient group. Effusion was seen in 8% of TMJs in the control group and 6% of TMJs in the patient group. No signs of bleeding or edema in the soft tissues were observed. In 15% of the patients, mild clinical symptoms in the TMJ or masticatory muscles developed in association with the trauma; in one third of these patients the symptoms were transient. CONCLUSION This prospective study does not show any significantly increased incidence of disk displacement, joint effusion, or any other injury to the TMJ after whiplash trauma that could be revealed by MR imaging.