The aim of the study was to estimate the effect of arthrocentesis in the treatment of osteoarthritis of the temporomandibular joint (TMJ), evaluate and compare cytological and biochemical findings in the synovial fluid (SF) as well in venous blood samples and to determine the effectiveness of arthrocentesis with regard to TMJ pain intensity and mandibular movement.
Twenty three consecutive patients with a diagnosis of TMJ osteoarthritis (Wilkes´ stages III, IV) after noneffective conservative treatment were treated with arthrocentesis using push and pull technique (Alstergren et al. 1995). Preoperative radiographs and the scores pre- and posttreatment (after 6 months), maximal interincisal opening (MIO) and visual analogue scale (VAS) for pain estimation were performed. Blocking the auriculotemporal nerve with a 2 mL of 2% lidocaine solution, the needle was inserted into the upper joint compartment and connected with the three-way stopcock for infusion therapy (Discofix® Braun) and 2-3 mL of saline solution was pushed slowly to the upper compartment and then aspirated back. The first SF aspirate was allocated for the following analysis: SF viscosity, presence of crystals, SF rheumatoid factor (RF) compared to blood plasma RF. The washing was repeated 3-4 times until the aspirate was clear.
After 6 months MIO improved significantly (p<0.05) and pain according to VAS had substantially decreased (p<0.01). Viscosity of the aspirate was 0.78 (medium), crystals were found in 5 patients (21.7%). There was not statistical significant difference between SF RF and plasma RF values (p>0.05).The effectiveness of arthrocentesis may be explained by the joint space expansion achieved with the introduction fluid, washing out inflammatory mediators, the particles of adhesions, fibrillations, crystals etc.
Arthrocentesis with this technique for the treatment of TMJ osteoarthritis offer favourable results with regard to increasing MIO, reducing pain and dysfunction. The presence of crystals or chondromatosis granules in the synovial fluid and increased viscosity of the synovial fluid indicates a pathological condition of an inflammatory nature.