1. Department of Clinical Chemistry and Department of Clinical & Experimental Medicine; Linköping University; SE-581 85 Linköping Sweden
2. Charles Salt Centre for Human Metabolism; Robert Jones & Agnes Hunt Orthopaedic Hospital; Oswestry UK
3. Department of Orthopaedic Surgery & Traumatology; College of Health Sciences; Obafemi Awolowo University; Ile-Ife Nigeria