The kneecap (patella) and the smaller bone that runs alongside the tibia (fibula) also help make the knee join. Image: WebMD The thigh bone, or femur, makes up the top part of the joint.

“The posterior tibialis is a muscle that originates on the back, or posterior, part of the tibia and fibula (your lower leg bones), up close to your knee,” explains Cathlin ...

The talus, meanwhile, is the bone situated between the tibia, fibula, and heel which forms ... the posterior malleolus is the structure least likely to be fractured on its own.