Methods After obtaining ethics committee approval from the Medical Ethics Committee, University Malaya Medical Center, Kuala Lumpur, Malaysia (Chairperson Professor Dr. Looi Lai Meng; IRB reference no. 949.14 dated 17 October 2012, amendment no.1038.76 dated 19 December 2013) and written informed consent, 18 patients undergoing surgery of the elbow, forearm, wrist, or hand were prospectively recruited based on the criteria below.