Handmade articulating spacer for two-stage exchange at the knee

Two-stage exchange with implantation of a temporary spacer is considered gold standard treatment for chronic periprosthetic joint infection of the knee. This article describes a simple and safe technique for handmade articulating spacers at the knee.

Chronic or relapsing periprosthetic joint infection of the knee.

Known allergy against components of polymethylmethacrylate (PMMA) bone cements or admixed antibiotics. Inadequate compliance for two-stage exchange. Patient not able to undergo two-stage exchange. Bony defect situation at the tibia or femur leading to collateral ligament insufficiency. Soft tissue damage with need for plastic temporary vacuum-assisted wound closure (VAC) therapy.

Removal of the prosthesis, thorough debridement of necrotic and granulation tissue, tailoring bone cement with antibiotics. Preparation of a tibial and femoral stem. Customizing the tibial and femoral articulating spacer components to bony anatomy and soft tissue tension. Confirmation of correct position by intraoperative radiography.

Protection of the spacer with an external brace. Restricted weight-bearing. Passive range of motion as possible. Intravenous-followed by oral antibiotics. Reimplantation after successful treatment of infection.