Clem has been diagnosed with a heart condition which, while not life-threatening, prohibits him from continuing his career as a professional rugby player.

Whilst at university in Edinburgh where he completed a Mechanical Engineering degree, Clem played club rugby for Currie and captained the club in his final year at university. Rugby entered the professional era as Clem graduated and he moved to Bedford at the beginning of 1996-97 season. In 1999 Clem moved to Bath RFC on a two year contract but returned home after his first season when he won a place in the Ulster squad.

Ulster Rugby coach Alan Solomons commented; It is sad for Clem that his career has ended prematurely. This year presented a great opportunity for him and it is a great shame that circumstances have denied him this chance. Clem has been an invaluable member of the Ulster squad and his presence will be sorely missed, however, I am sure that he will continue to make a valuable contribution to Ulster Rugby."

Capped 24 times for Ulster and a prominent member of Belfast Harlequins RFC, Clem has been a loyal servant to the game and Ulster Rugby would like to extend their very best wishes for a successful future.