Case Study: Treatment of infected knee replacement. A staged reconstruction in a 64 year old male
A 64 year-old gentleman who received a Revision Total Knee Replacement at another institution approximately 18 months prior to being seen at our clinic with ongoing pain that had bothered him ever since his original surgery. He was referred to us for a second opinion.
We performed a comprehensive assessment of Mr. KJ’s medical and surgical background and knee pain before and after his surgery. His BMI was 45 and his medical history included Type 2 Diabetes, Hypertension, High Cholesterol and Cardiovascular disease. His medication list reflected these diagnoses, as well varying pain medications he had been taking in an attempt to control his ongoing knee pain.
He described the pain as being global around the knee, worse with activity (not necessarily just weight-bearing) and has responded with varying degrees of success to numerous pain medications he had used. No other remarkable findings were found on examination of his knee, save for mild swelling as compared to the contralateral side.
X-rays revealed an appropriately sized and positioned Revision Total Knee Replacement prosthesis with a resurfaced patella and no obvious signs of loosening or periprosthetic fracture.
We arranged for Mr. KJ to undergo blood tests in the form of serum inflammatory markers. These returned as being elevated sufficiently to raise the possibility of a periprosthetic infection. As such, we performed an arthrocintesis of his right knee, the results of which confirmed our suspicion of a periprosthetic infection. The synovial fluid sample eventually grew a bacteria of the Serratia family.
Given the length of Mr. KJ’s symptoms, it was decided that an Irrigation & Debridement with a polyethylene liner exchange would be insufficient to eliminate the infection; as such we counselled him that he would require a two-stage Revision Knee Replacement.
He consented to this, and we performed the 1st stage of his revision within 3 weeks of his diagnosis. We removed all the prosthetic components and replaced these with articulating spacer components, constructed entirely of antibiotic-laiden cement. These will be allowed to elute their antibiotics locally, along with systemic antiobiotic therapy until the infection is deemed to be eradicated – indicated by decreasing serum inflammatory marker levels.
We are currently planning his 2nd stage revision where he will have these spacers removed and Revision Total Knee Arthroplasty components reimplanted.