Surgical site infections after total knee arthroplasty - an audit from ‘catch up arthroplasty’ weeks at Helen Joseph Hospital

Abstract

Introduction: There is a paucity of literature on lower limb arthroplasty from local South African and Sub-Saharan African populations. South African State hospitals have demonstrated long elective lower limb arthroplasty waiting lists. To decrease these waiting times, Helen Joseph Hospital, a South African State hospital, has initiated ‘catch up arthroplasty’ weeks. Aim: To perform an audit of the epidemiology and determine the prosthetic joint infection and superficial sepsis incidence rates in patients undergoing total knee arthroplasty during ‘catch up arthroplasty’ weeks at Helen Joseph Hospital. Methodology: One hundred and seventeen (117) patients’ files from ‘catch up arthroplasty’ weeks at Helen Joseph Hospital were retrospectively reviewed. Biochemical, histological and microbiological results were retrieved via the National Health Laboratory Service database. Analysis was performed between patient variables (demographics, comorbid diseases etc.) and three outcome measures: prosthetic joint infection, superficial surgical site infection and overall post-operative surgical site infection. Prosthetic joint infection was defined using the 2018 revised Musculoskeletal Infection Society criteria. Results: The average waiting time for total knee arthroplasty was 19.9 months. The average age was 64.4 years. Eighty three percent (83%) of the total knee arthroplasty procedures were performed on females. Osteoarthritis was the underlying diagnosis in 96.9% of cases. Type I obesity was the most common World Health Organisation body mass index category and 80% of the population was overweight. The average operative time was 106.4 minutes. The prosthetic joint infection incidence was 0.85%, and the superficial surgical infection incidence was 9.40%. Conclusion: This was the first study to objectively determine a prosthetic joint infection incidence in Sub-Saharan Africa using validated criteria. The paucity of data from South Africa and Sub-Saharan Africa on audits of this kind demonstrates that more studies of this nature are needed to understand the differences in demographics and epidemiology of total joint arthroplasty populations and how these differences translate into risks for post-operative infective outcomes in our region.