Revision Knee Arthroplasties Done at Muhimbili Orthopaedic Institute, Tanzania, between 2007 and 2018

Introduction There has been a steady rise in the need for Revision Total Knee Arthroplasty (RTKA) due to increasing longevity and expanding indications of primary TKA. Worldwide revision rates vary between 4.9-7.9%. However, in the sub-Saharan African region, revision total knee arthroplasty has rarely been studied. Broad Objective To determine the rate and indications for RTKAs in primary TKA surgeries operated at MOI between 2007 and 2018. Methodology This was a retrospective study. Revision TKA surgery data was collected from the TKA registry. Univariate analysis and descriptive statistics were used for analysis and presentation of categorical and continuous data. Statistical significance was determined in all relevant associations. Results Out a total of 607 primary TKA procedures recorded, 40 required revision, with a mean age of 69.1 years, a female predominance (60%) and a left knee predominance (62.5%), giving a revision rate of 6.59%. The causes of revision TKA included aseptic loosening (47.5%) and periprosthetic infections (32.5%). Both femoral and tibial components were revised in 50% of the surgeries. The mean duration from primary surgery until revision surgery was 4.1 years. Prosthesis infection was associated with early revision surgery (p value 0.008) but most patients had late revision TKA surgery (p value 0.02). Conclusion The rate of revision TKA at MOI was similar to worldwide rates. Most revisions were done late (after 2 years), and the predominant cause of revision was aseptic loosening, but infection was positively associated with early revision.