Left knee medial compartment joint replacement hardware with abnormal uptake of tracer in the medial left femoral condyle proximal to the prosthesis.

Varies : It varies in part on the type of scan you underwent and the timing of when your knee replace my was done as well. A standard bone scan will light up with increased bone activity and would be concerning for loosening, infection, or fracture. A white blood labeled scan that lights up whilst be concerning for infection. I would discuss with your surgeon.