1. Department of Rehabilitation Medicine, Daejeon Sun Hospital, Daejeon 301-725, Korea.
2. Department of Orthopedic Surgery, Daejeon Sun Hospital, Daejeon 301-725, Korea.
3. Department of Rehabilitation Medicine, School of Medicine, Chungnam National University, Daejeon 301-721, Korea.
4. Department of Rehabilitation Medicine, School of Medicine, Kangwon National University and Hospital, Chuncheon 200-722, Korea.