Graduating with honors in 1996, Rehan went on to complete his orthopedic training at the Irish Higher Surgical Training program in 2006.

He completed his fellowship training in joint replacement and sports surgery at the world renowned SPORTSMED SA in Adelaide, Australia in 2007.
Rehan has been working as a consultant Orthopedic Surgeon in Cork since 2009.He has a high volume practice, focusing on primary and revision hip and knee replacement. He is skilled in advanced techniques in managing complications of failed or painful and knee replacement. Although he has a specialty interest in total joint replacements, he also provides surgical treatment for fractures, sports related injuries around knee, foot and ankle surgery.

He published multiple articles in peer reviewed orthopedic journals and has presented his research regionally, nationally and internationaly. He is on the specialist register with the medical council in Ireland with operating credentials at cork university hospital, South infirmary Victoria university hospital and Bon Secours Hospital cork.