The Most Devastating Complication in Knee Replacements: PJI + Extensor Disruption

A retrospective review across 5 tertiary centers uncovers the catastrophic failure rates of attempting to reconstruct an extensor mechanism in the setting of a periprosthetic joint infection.

Infection following total knee arthroplasty (TKA) remains one of the most dreaded and difficult complications to treat. The overall incidence of infection in the literature ranges between 0.5% and 2% for primary TKAs and 2% and 4% for revision TKAs. While successful eradication of periprosthetic joint infection (PJI) has been reported in the range of 85%-95%, the mortality associated with PJI is high.

Disruption of the extensor mechanism is an infrequent but catastrophic complication following TKA. Repair or reconstruction of the extensor mechanism disruption (EMD) is technically challenging. A recent longitudinal study of patients treated with extensor mechanism reconstruction (EMR) using allograft demonstrated 69% of knees retained the allograft at a mean follow-up of 68 months. However, the reoperation rate was high at 58%, with the most common reason for reoperation being the development of PJI at 26%.