2004 Abstract : CS 7

Authors: Charalampos G. Zalavras, MD, PhD, Michael J. Patzakis, MD, James Tibone, MD,
Nick Weisman, MS, Paul Holtom, MD

Title: Failed Management of Septic Arthritis of the Knee Following Anterior Cruciate Ligament Reconstruction: The Role of Tunnel Osteomyelitis and Multiple Cultures

Addresses: Department of Orthopaedic Surgery, University of Southern California, LAC+USC Medical Center, 1200 N State St GNH 3900, Los Angeles, CA 90033

Purpose: Infection following anterior cruciate ligament (ACL) reconstruction is a rare complication. Failed management and recurrence of infection constitutes a challenging problem with very limited information in the literature. The purpose of this study is to present the clinical characteristics and microbiology of recurrent such infections, and evaluate our management protocol.

Methods: This is a retrospective review of 5 consecutive patients who were referred to our institution for recurrent septic arthritis of the knee following ACL reconstruction. Our protocol consists of open arthrotomy, complete synovectomy, removal of interference screws or other implants, graft removal, and currettage of the femoral and tibial tunnel. Cultures are obtained from multiple tissues, including joint fluid, synovium, graft, and bone. Antibiotic therapy is given for 6 weeks.

Results: All patients were male of a mean age of 39 (27 to 56) years. Three patients had co-morbidities. An allograft was used for ACL reconstruction in 4 patients and a hamstring autograft in one patient. Infection developed at a median time of 20 (5 to 71) days following surgery. All patients had previously undergone one or more (1 to 3) arthroscopic or limited open irrigation and debridement procedures with recurrence of the infection. Patients presented at our institution at a median time of 23 days (11 days to 22 months) following the diagnosis of infection. Two infections were caused by Staphylococcus aureus, whereas three were polymicrobial. In two of the polymicrobial cases, different organisms grew on the synovium, bone, and graft specimens. At a median follow up time of 20 months (6 to 27 months) all patients were free from infection.

Discussion: Failed management of infection following ACL reconstruction is a challenging problem and the low incidence precludes the accumulation of large series from a single center. In our experience, inadequate debridement, especially of the femoral and tibial tunnel, is a key factor in recurrence of infection. We advocate arthrotomy, complete synovectomy, hardware and graft removal, and debridement of the femoral and tibial tunnels. The development of adjacent osteomyelitis jeopardizes eradication of infection with less invasive means. Polymicrobial infections may be present; therefore we recommend multiple cultures from different sources to identify all pathogens.

Significance: Aggressive debridement of recurrent infections following ACL reconstruction, with attention to the role of adjacent tunnel osteomyelitis and multiple cultures, is necessary for eradication of infection.