New Delhi:

Chronic back pain has emerged as a point of interest in the murder investigation of UnitedHealthcare CEO, who 26-year-old Luigi Mangione allegedly gunned down in New York last week.

Mangione, an Ivy League graduate, yelled and struggled as he was taken into a courtroom in Pennsylvania after he was held from a McDonald's in Altoona on Monday, ending over a week-long nationwide manhunt after Brian Thompson was shot down in Manhattan. He is in custody in Pennsylvania and faces multiple charges there as well as murder charges in New York.

As police say the head of one of US's biggest health insurers was deliberately targeted, a trail of posts on social media by Mangione could point to likely grievances he harboured against the healthcare system. Mangione was also arrested with a manifesto where he accused health insurance companies for putting corporate greed over the well-being of people, according to NY Post. This has led to theories that the murder could be linked to Mangione's disappointment with the insurance provider.

Mangione lived in Hawaii in 2022 and, according to his former roommate RJ Martin, suffered from back pain, and was hoping to strengthen his back. After a surfing lesson, Mangione was "in bed for about a week" because of the pain, Martin told CNN. Earlier this year, Mangione confirmed he'd had back surgery and sent him photos of the X-rays, Martin said.

He also told the manager of Surfbreak, the co-living residence in Hawaii he resided at, that he had a back problem, and in August of 2023 sent him pictures of a back surgery, according to the New York Times. "His spine was kind of misaligned. He said his lower vertebrae were almost like a half-inch off, and I think it pinched a nerve," Mr Martin told New York Times. "He knew that dating and being physically intimate with his back condition wasn't possible," he added, while saying that Mangione was a young man yearning a normal lifestyle.

Mr Martin said that Mangione left Hawaii in the summer of 2023, presumably for an operation on his back. In August that year, he checked in via text to see how his friend was doing, "and he sent me back pictures of his back surgery."

On his X profile, he shared a picture of an x-ray of a spinal surgery and on GoodReads, he reviewed a book called "Crooked: Outwitting the Back Pain Industry and Getting on the Road to Recovery."

Another account was narrated by Paul Piek, a 21-year-old software testing professional from Flensburg, Germany, met Mangione in March while watching a muay thai boxing fight in Ao Nang, Thailand. The two and another friend of Piek's met up again in Krabi, Thailand on April 8 and roadtripped through Khao Sok and Bangkok, where they shared a hotel room for four nights and visited temples. "He told us he did (muy thai) before his injury," said Piek.

Piek said Mangione told him he was interested in hiking when they met, with no further mention of his back injury. "It didn't seem like a problem," though he did opt out of one guided hike for an easier walk, saying he was ill.

Mangione had left his previous employer Truecar, a car-purchse platform with offices in California, in 2023, the company said. A colleague he worked with there told Reuters he took leave during the middle of 2023 for about two months, a move the colleague's manager told him was due to back-related issues.

Further, a deleted Reddit account allegedly associated with Mangione wrote multiple comments in a subreddit for people diagnosed with spondylolisthesis, Forbes reported. The user wrote the condition "went bad on me" and was "completely devastating as a young athletic person" because they learned the condition would force them into "a desk job for the rest of my life."

In a 14-page handwritten document that Sky News identified as having been uploaded to his Google Drive account in 2021 and which has not been independently verified by Reuters, Mangione said he had a back injury known as an L5-S1 isthmic spondylolisthesis, in which one of the bones in the spine slips forward and presses on the vertebra below it. Mangione's notes mention that his condition involved a stress fracture in the pars bone that connects the vertebrae to the spinal column.

Mangione's profile on X includes an X-ray of a person who has had an L5-S1 spinal operation in which two vertebra are surgically fused together. The surgery has an overall success rate of 80%, according to the National Institutes of Health.