A Torqued Tibia

Rotational stresses acting on the proximal tibia (where the large bone in the lower leg, the tibia, articulates at the knee) are common in people who drive a lot, e.g. for a job.

The tibia is not meant to rotate at this joint, but will tolerate some rotational stresses for short periods of time or if the stress is not repetitive or chronic.

Patients whose work requires a lot of driving often come in with aberrance and pain in their right (gas / brake foot) knee. Usually I find, and adjust to relieve / correct, rotational stress of the involved proximal tibia. 

Medicare "Advantage" Plans

If you are eligible for Medicare, but choose a Medicare Advantage Plan, you have opted for private insurance that is outside of Medicare.

Medicare Advantage plans are offered by private companies, e.g. Humana, United Health, Blue Cross, etc., and often include benefits not provided by regular Medicare, such as vision, dental, etc. 

This type of private insurance plan must conform in certain ways to the rules of Medicare--such as limiting charges for certain services--but is administered by the private companies which sell the plans. Patients still have many of the rights and protections provided under original Medicare.