Total knee arthroplasty (TKA) is a frequently performed operation – in the U.S. alone, 5.2 million TKAs were performed from 2000-2010 – and partial (unicompartmental) knee arthroplasty (UKA) is another common operation that is done in younger, active individuals. Many patients require knee arthroplasty from osteoarthritis that develops after sports injuries or decades of participation in athletics. While much has been written regarding technical surgical details of arthroplasty, there is comparably little available on critical rehabilitation principles and guidelines that allow return to normal physical function, as well as recreational and sports activities.