Vitamin D in Knee Replacements

The purpose of this study is to determine how common lack of vitamin D is among knee replacement patients and whether there is a relationship between vitamin D levels at the time of surgery and physical disability before or recovery after surgery. Vitamin D levels are currently being obtained as standard of care in all knee replacement patients immediately following surgery by the participating surgeons. Additionally, patients' responses to preoperative and postoperative questionnaires, which are also being given to all knee replacement patients, will be collected and analyzed to determine the level of disability prior to and 3 months after total knee replacement.