Tibial prosthesis having one or more fins for use in a total or unicompartmental knee athroplasty procedure are disclosed. The one or more fins can be adapted to fix a tibial prosthesis to the tibia and can engage with corresponding channels formed in the resected tibia. Additionally, intercondylar components and methods for use in a total or unicompartmental knee athroplasty procedure are disclosed. The intercondylar component can be integral with or attached to a baseplate configured for attachment to a partially resected proximal surface of the tibia that retains at least a portion of the intercondylar eminence and the anterior cruciate ligament (ACL) and/or the posterior cruciate ligament (PCL). Inner surfaces of the intercondylar component can be configured to engage with at least a portion of the intercondylar eminence remaining with the partially resected tibia. In an example, the intercondylar component or the one or more fins can be formed of a porous material, such as to facilitate bone growth.