Early diagnosis of osteoarthrosis of the temporomandibular joint: correlation between arthroscopic diagnosis and keratan sulfate levels in the synovial fluid.

The role of osteoarthrosis (OA) and proteoglycan degradation in the pathogenesis of temporomandibular joint (TMJ) disorders has not been well established. The orthopaedic literature has demonstrated that proteoglycan degradation plays a significant role in the pathology of many joints. The purpose of this investigation was to determine if levels of immunoreactive keratan sulfate (an important component of cartilage proteoglycans) present in synovial fluid aspirates from TMJs correlated with arthroscopically demonstrated OA. Temporomandibular joint arthroscopy was performed on 25 joints in 20 patients and synovial fluid aspirates were obtained just prior to the insertion of arthroscopic cannulas. The results showed that synovial fluid aspirates from joints that arthroscopically demonstrated OA had significantly higher levels of keratan sulfate than synovial fluid aspirates from those joints that showed no evidence of OA (NON-OA). This study gives support to the theory that the pathogenesis of OA of the TMJ is similar to that of chondromalacia of other synovial joints. The combination of TMJ arthroscopy and synovial fluid analysis is an important model that can be used for investigation of the pathogenesis of TMJ disorders.