MacCulloch played center for the Philadelphia 76ers and New Jersey Nets before being forced to retire prematurely due to a genetic neuromuscular disorder that affected his feet, Charcot-Marie-Tooth disease.

A graduate of Shaftesbury High School in Winnipeg, MacCulloch was named Honorable Mention All-America in 1999 as a senior when he averaged 24.7 points, 15.9 rebounds, and a .662 field goal percentage.

He later led the NCAA Division I in field goal percentage in his final three years of college at the University of Washington, only the second player ever to accomplish the feat.

MacCulloch played four seasons in the NBA before being forced to retire prematurely due to a genetic neuromuscular disorder that affected his feet, Charcot-Marie-Tooth disease.

Due to an inherited neurological disorder, Charcot-Marie-Tooth disease, which affects the peripheral nerves of the hands and feet he went on the injured reserve list at mid-season,[3] did not play the following season, and announced his retirement in September 2004.