Magnetic resonance images in patients with acute traumatic injury of the temporomandibular joint: a preliminary report.

Condylar or subcondylar fractures are severe traumatic lesions of the temporomandibular joint (TMJ) but the damage to the intracapsular soft tissues is not fully defined. In this study, twelve joints in ten patients with condylar and subcondylar fractures of the TMJ between two and twelve days after injury, were examined by magnetic resonance imaging to evaluate the damage to the intracapsular soft tissues in the acute phase. The joint capsule and the retrodiscal tissue were both swollen and showed increased signal intensity. Tears were recognized in the capsule of the eight joints and in the retrodiscal tissue of six joints. All discs were displaced in an anteromedial direction along with the fractured condylar fragments, but tear (rupture) was not recognized. In all cases, high signal intensity was seen in the joint spaces, and haemarthrosis was recognized in six joints during open reduction surgery.