In 2009, Dole was hospitalized for an elevated heart rate and sore legs for which he underwent a successful skin-graft procedure. In February 2010, Dole was hospitalized for pneumonia after undergoing knee surgery. He spent ten months at Walter Reed Army Medical Center, recovering from the surgery, and experienced three bouts with pneumonia. He was released from the hospital in November 2010. In January 2011, however, Dole was readmitted to Walter Reed Army Medical Center and spent about six days there, being treated for a fever as well as a minor infection.