Treatment of Staphylococcal Joint Infection in the Rabbit by Administration of Systemic Antibiotics and Intra-articular Corticosteroids

Background/objective: Despite the present routine treatment of septic arthritis with antibacterial agents, articular damage is persistent and frequently leads to loss of joint function.  The aim of this study was to assess the effect of intra-articular corticosteroids added to systemic antibiotics in the treatment of experimental staphylococcal knee joint infection in rabbits. Methods: Thirty rabbits were injected in their knees by Staphylococcus aureus.  The rabbits were divided into 3 equal groups.  In group A, rabbits received no treatment.  In group B, rabbits were treated with systemic antibiotics alone.  Group C, received systemic antibiotics and intra-articular corticosteroids.  After 16 days animals were killed and knee joint X-Ray as well as histopathological–histochemical parameters were assessed. Results: All rabbits survived the experiment; the treated groups (B,C) had better histological–histochemical scores in comparison with the untreated group (A).  Group C had significantly better scores in joint sections in comparison with group B (mean SD = 6.7   ± 2.3 v 4.0 ± 2.4; P= 0.019).  Lower damage in the former group was expressed in lesser clustering of chondrocytes, proteoglycan depletion, and severity of synovitis.  Radiological soft tissue scoring was significantly better in group C in comparison with group B.  Three peri-articular abcesses were observed in group C but none in group B. Conclusion: Addition of intra-articularly administered corticosteroids to antibiotic treatment of septic arthritis improved histological histochemical parameters in this experimental setting, although on account of the clinical observation of three cases with peri-articular abcesses in this group, caution is warranted in interpretation of these results.