Investigators are piecing together a timeline and motive leading up to the killing of UnitedHealthcare CEO Brian Thompson, but in the meantime, a clearer picture is coming together about the alleged gunman, Luigi Mangione. And it's believed that the 26-year-old suffered from a spinal condition that likely caused him excruciating pain.
In 2019, Mangione detailed in handwritten notes reviewed by Business Insider that he was afflicted with a joint deterioration condition called spondylolisthesis.