The lawsuit, filed in state court of Spalding County in Georgia, said McGee was driving distracted and did not see Maynard's car merging onto the highway.
McGee's car struck Maynard's car, which sent his vehicle across the left lane and into an embankment.
"It crushed the back left side of Maynard’s Outlander and caused trauma to his body and brain that would alter the rest of his life," the statement said.
BuzzFeed News reported that McGee posted her injuries after the crash to Snapchat with the caption, "lucky to be alive," the complaint said.
Maynard now uses a wheelchair and spent weeks in intensive care for a severe tramatic brain injury, according to the suit.
Maynard and his wife are suing Snapchat and McGee to pay his medical bills following the accident, which the suit said has caused him to miss work, as he was working as an Uber driver at the time of the accident.
A Snapchat spokesman told CNN Money he could not comment on an ongoing lawsuit, but added that Snapchat has a warning not to use the miles per hour filter while driving.