Career
He was top scorer at the 2008 championship together with Nikola Karabatic and Ivano Balić, and was also voted into the 2008 All-star team Christiansen has played 338 games for the Danish national team, and scored 1503 goals. He is currently the player with most games and most goals for the Danish national team
In his 14 years with SG Flensburg-Handewitt he scored 3996 times, 1623 of these was scored from the 7 meter penalty spot.
He has been married to former handballer, Christina Roslyng, who played at the Danish national handball team Together, they have a son, Frederik.
They split up in 2009, however, as of 2012, they are back together. Club Team National Team.