The medial and lateral condyles of the tibia articulate with the

patella bone

Explanation:

Although, the condyles articulate with the tibia to form the knee joint. But, Anteriorly, the smooth surfaces of the medial and lateral condyles join together to form a wide groove called the patellar surface, which provides for articulation with the patella bone.  The epicondyles(a protuberance above or on the condyle) provide attachment for muscles and supporting ligaments of the knee.

Posteriorly, the medial and lateral condyles are separated by a deep depression called the intercondylar fossa.  The combination of the medial and lateral condyles with the patellar surface gives rise to  the distal end of the femur a horseshoe (U) shape.