Multiple arthroscopic debridement and graft retention in septic knee arthritis after ACL reconstruction: a prospective case–control study

Abstract

This study was undertaken to prospectively analyse, at a mean five-year follow-up, the clinical, functional, and radiographic outcomes in patients who developed postoperative acute septic knee arthritis following anterior cruciate ligament (ACL) reconstruction using hamstring autograft. We also assessed the effect of multiple arthroscopic debridement and graft retention on the functional outcomes in comparison with the matched control group. From a consecutive case series of 2,560 ACL-injured patients who were treated with arthroscopic ACL reconstruction, we report on 24 cases with postoperative septic knee arthritis. These patients were individually matched for age, sex, comorbidity, body mass index (BMI) and preinjury Tegner activity scale in a ratio of 1/1. Clinical, laboratory, synovial fluid analysis and culture were performed. Arthroscopic debridement and graft retention was done for all cases, in addition to antibiotic therapy i.v.. A detailed physical examination, KT1000 laxity testing, Lysholm knee score, Tegner activity level scale, International Knee Documentation Committee (IKDC), and Knee Injury and Osteoarthritis Outcome Score (KOOS) were completed. In all cases, treatment of infection was successful after a median of three (range one to six) repeated arthroscopic graft debridement and retention, in addition to antibiotic therapy i.v.. At an average of five years follow-up, two patients had over five millimetres manual maximum side-to-side difference in laxity. There were no significant differences between groups regarding Lysholm score, IKDC and KOOS. Median final Tegner activity score was 5.5 versus 7 in the control group (p = 0.004). Complications included graft rupture in three patients, loss of range of motion in five, Sudeck's atrophy in one and moderate joint narrowing in two. There were no recurrences of septic arthritis or bone infection. Graft retention seems not only possible but appropriate in view of the experience presented in this article for postoperative septic knee arthritis using hamstring autograft. A potential residual complication is arthrofibrosis, which deserves maximum attention.