Internal derangement of the temporomandibular joint: Can clinical and magnetic resonance imaging features predict the prognosis?

Abstract

Purpose: To evaluate the role of magnetic resonance imaging (MRI) in the diagnosis of internal derangement and to assess the complimentary role of MRI and clinical assessment in prognostication. To assess the role of MRI in demonstrating disc displacement and reduction. Methods: A total of 34 patients (28 cases and 6 controls) with clinical features of temporomandibular joint (TMJ) internal derangement underwent a dedicated MRI at our institution. MRI was assessed for disc displacement, morphology, and reduction on open-mouth imaging. For analysis, the patients were divided into those with disc displacement with reduction (WR) and those without reduction (WOR). Clinical and MRI grading of internal derangement were done in all patients and correlated with each other. Prognostication was attempted using the clinical and MRI features, and patients were followed up over a mean period of 6 months. Results: Most of the patients were females (n = 20 71%) in the child-bearing age group (third decade). MRI demonstrated disc displacement in all but two patients in whom disc was not visible. Fourteen (54%) patients were placed in WR group, whereas 10 (38%) were in WOR group. In two (8%) patients, stuck disc was diagnosed. Patients in WR group responded to conservative treatment alone while those in WOR group needed conservative management in some (n = 8 57%) and surgical intervention in others (n = 6 43%). Both patients with stuck disc failed conservative management. Conclusion: MRI is an essential component of TMJ evaluation and helps in diagnosing and staging internal derangement together with disc assessment. Patients with disc displacement WOR and those with higher grades of derangement on MRI including stuck disc require surgical intervention if conservative management fails.