Summary

Early surgical debridement with or without removal of the plate is the effective treatment of postoperative deep infection after osteotomy around the knee.

Abstract

Objectives
Postoperative deep infection is a serious complication in osteotomy around the knee; however, the treatment of infection has not yet been established. The purpose of this study was to investigate cases of knee osteotomy that resulted in deep infection and required surgical debridement.

Methods

We included 1277 knees in 951 patients who underwent osteotomies at our hospitals between April 2010 and December 2023. The surgical techniques were open wedge high tibial osteotomy (OWHTO) for 284 knees; open wedge distal tuberosity osteotomy (OWDTO) for 501 knees; closed wedge high tibial osteotomy (CWHTO) for 262 knees; distal femoral osteotomy (DFO) for 101 knees; double level osteotomy (DLO) for 114 knees; and tibial condylar valgus osteotomy (TCVO) for 15 knees. The incidence of infection, patient demographics, duration from surgery to infection, duration from diagnosis to debridement, causative organisms, treatment modalities, and outcomes were reviewed.

Results

There were 33 knees (2.6%) of suspected deep infection. The rate of occurrence for each procedure was as follows: OWHTO, 11 knees (3.9%); OWDTO, 14 knees (2.8%); CWHTO, 6 knees (2.3%); DFO, 0 knees (0.0%); DLO, 1 knee (0.9%); and TCVO, 1 knee (6.7%). The mean age was 58.8 years (40-79), and the mean BMI was 26.9 (19.3-39.6). Comorbidities were diabetes in 7 knees (21.2%), rheumatoid arthritis using steroid drugs in 1 knee (3.0%), and atopic dermatitis in 1 knee (3.0%). Six patients (18.2%) smoked. The mean time of infection was 92 days (17-292 days), and the time from diagnosis of infection to treatment was 4.3 days (0-31 days). The organisms were MSSA in 17 cases, MRSA in 4 cases, CNS in 1 case, group A streptococcus in 1 case, group G streptococcus in 1 case, Pseudomonas aeruginosa in 1 case, and Acinetobacter baumannii in 1 case. Eight were not identified. We underwent debridement of infected knee as early as possible after diagnosis of infection. The 29 knees that had not yet achieved bone union retained their plates, while the 4 knees that had already fused simultaneously had their plates removed. Two of the plate retention knees required additional debridement. In all cases, the infection resolved and the plates were able to be preserved until bone fusion.

Conclusions

Deep infection after AKO occurred in 2.6% of patients, but in all cases the infection subsided after debridement, with or without removal of the plate. Early postoperative cases also successfully retained the plate until bone fusion.