Employee was stepping out of van, there was a skiff of snow covering some ice; he slipped on the ice. He had just returned on12/20/04 full duty from right knee replacement surgery. X-rays taken at NNRH ER showed no problems with knee. Diagnosed with strain, knee was wrapped with ace and given crutches. Follow up with orthopedic surgeon on 01/05/05 @ 9:45 am.