Presentation
Fever, pain, swelling and redness of skin about the left knee after total knee arthroplasty and subsequent revision with spacer implantation.
Patient Data
Replacement of knee joint's articular surfaces with antibiotic joint spacer which is secured using cement and two k-wires.
Abundant air bubbles within the cement and in the joint space, which is a sign of severe infection.
Severe demineralization of bone tissue around the spacer elements.
Some bony fragments about the knee joint - probably post surgery.
Missing patella.
Fluid within the joint.
Generalized atrophy of the visible muscles.
An additional x-ray performed some time before the CT examination. The findings are similar for both modalities.
Case Discussion
Unfortunately, the full medical history of this patient was not attainable, so the exact causes of this appearance of the knee are not fully known.
This is a quite spectacular case of a failed antimicrobial treatment as a complication of a procedure known as two-stage reimplantation. This procedure is nowadays regarded as the gold standard in the treatment of periprosthetic joint infection.
During this procedure, the infected endoprosthesis is removed from the joint space along with nonviable bone, synovial and necrotic tissues. After that, the antibiotic-coated spacer is placed into prepared joint cavities to locally treat the periprosthetic infection. The second stage is performed after confirmation of successful antibiotic therapy and it consists of removal of the spacer elements and replacing them with final endoprosthesis.