Association between Arthralgia and Imaging Findings of Effusion in the Temporomandibular Joints: A Systematic Review

The temporomandibular disorders (TMD) encompass a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints (TMJs), the masticatory muscles, and associated tissues [1]. Common manifestations of TMD consist of pain of a persistent, recurring, or chronic nature in the TMJ, masticatory muscles, or in the adjacent structures; limitation or other alterations in the range of mandible motion; and TM joint noises [2]. It has been suggested that differential diagnosis of TMDs should be based primarily on information obtained from the patient’s history, clinical examination, and when TMJ imaging procedures indicated [1]. Magnetic resonance imaging (MRI) is an example of such imaging procedures. It provides excellent representation of soft tissues in anatomical and semi-functional relationships. In addition, it may also be used for detection of the presence of joint effusion with acceptable levels of reliability [3]. Some authors have also suggested use of MRI for assessment of hard tissues; however the reliability has been shown to be poor [3-5]. Joint effusion is defined as a collection of fluid in the joint space. It is manifested as areas of high intensity signal in the TMJ space, on T2-weighted images [3-5]. It has been suggested that this accumulation of fluid could be a surrogate of an inflammatory process that may activate or sensitize nociceptive afferent neurons within the joint [4-6]. Alternatively, it could result in increased intra-articular pressure, which may cause mechanical trauma, leading to hypoxia and other inflammation induced changes within the joint space, and eventually leads arthralgia [7]. Several studies have been conducted on the association of joint effusion and TMJ pain associated with TMD. However, the results have been inconsistent. While the majority of studies have reported a statistically significant association [4-26], others have reported inconclusive findings [5-30]. Due to this difference in reporting, a systematic review was conducted to determine if there is an association between joint effusion and self-reported TMJ-pain during examination, as well as between joint effusion and arthralgia as defined by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC-TMD) [31].