Marc was born with spina bifida. One of the most common birth defects, it involves incomplete closure of the lining of the spinal cord, resulting in an incomplete spinal cord. Vertebrae overlying the exposed area and unfused and open, which results in the abnormal part of the spinal cord protruding through the vertebrae. The lining can be closed surgically after birth, but the individual will continue to have dysfunction of the spinal cord, mainly affecting the muscles of the hips, knees and feet. Spina bifida, Latin for "split spine", affects 1.5 of every 1,000 births.
According to Teammate Jean Labonté
“Marc is not a big guy, but he's fast, shifty and has a great shot. Like Martin St. Louis, Marc has never let his size – or lack thereof – stop him and has never been afraid to go in the corners. And if that wasn't enough, he's also one of the best penalty killers in the game.”