1. Department of Applied Physics; University of Eastern Finland; P.O. Box 1627 70211 Kuopio Finland
2. Department of Clinical Radiology; Kuopio University Hospital; P.O. Box 100 70029 KYS Finland
3. Department of Orthopaedics; Traumatology and Hand Surgery; Kuopio University Hospital; P.O. Box 100 70029 KYS Finland
4. Department of Clinical Neurophysiology; Kuopio University Hospital; P.O. Box 100 70029 KYS Finland