A relatively small study--50 patients undergoing total knee replacement surgery vs. 50 controls getting PT alone--showed a significant benefit for the surgery. But complications occurred with surgery. Some of the nonsurgical patients elected surgery later. While not definitive, surgery works well for most with knee OA.
A new retrospective study shows a significant association between reduced rate of knee- and hip- replacement revision and treatment with hormone replacement therapy (HRT). A good candidate theory for prospective trial to confirm, or refute.