Arthroscopic management of septic arthritis: stages of infection and results

Seventy-six patients with septic arthritis (78 affected joints) were treate d with a combination of arthroscopic irrigation, debridement, and antibioti c therapy according to the tested bacterial sensitivity. There were 62 knee , 10 shoulder, 5 ankle joints, and 1 hip joint. No antibiotics were added t o the irrigating solution. The arthroscopic and radiological stage of infec tion, treatment, and outcome in these patients was analyzed. The patients w ere classified into three groups according to initial stage of joint infect ion (stage I: 21 patients, 22 joints; stage II: 43 patients, 44 joints; sta ge III: 12 patients, 12 joints). Causes of infection were: hematogenous dis semination in 54%, postoperative wound infection in 28% (17% after open, 11 % after arthroscopic procedures). Other causes were: 10% intra-articular st eroid injections, 3% diagnostic punctures, and 390 open traumatic injury of the joint. In 78% of the infected joints the causative organism could be i dentified: Staphylococcus aureus was the most common organism found (42%), followed by streptococci (15%), pneumococci (6%), Escherichia coli (4%), St aphylococcus epidemidis (3%), Borrelia burgdorferi, (3%), and others in 5%. In the stage I group only one patient needed repeated arthroscopic irrigat ion, in the stage II group 52%, and in the stage III group 75%. Open revisi on for eradication of the infection was necessary in one joint with stage I I and in two joints with stage III infection (3%). Two joints of the stage III group needed additional surgery after successful treatment of the infec tion. The combination of arthroscopic irrigation and systemic antibiotic th erapy was able to cure 91% of the affected joints. Open revision was necess ary in 4% of joints. The number of arthroscopic procedures and the efficacy of treatment depended on the initial stage of the infection. It is conclud ed that an arthroscopic staging of the initial joint infection has prognost ic and therapeutic consequences.