A method, apparatus and a system for thermally-assisted pulsed electromagnetic field stimulation for treatment of osteoarthritis in the knee are disclosed. A multi-coil applicator is adapted for positioning around the knee. A first coil is positioned on the top of the knee and provides electric field stimulation in the plane of the patella to stimulate the patella cartilage. Second and third coils are rectangular coils wrapped up below and above the knee respectively. The coils in the wrapped position generate a magnetic field along the knee axis and provide high amplitude of the electric field stimulation of the femoral and tibial cartilages in the plane of tibial plateau. Resistive heaters and free wheel diodes can be provided to the applicator to supply uniform thermal stimulation around the knee joint.