"If, hypothetically, the hyoid bone is broken, that would generally raise questions about strangulation, but it is not definitive and it does not exclude suicide," National Association of Medical Examiners President Jonathan Arden told The Washington Post.
Now an unnamed lawyer has told Forbes magazine Epstein and the mystery woman spent at least two hours locked alone in a "private room reserved for inmates and their attorneys".
"The optics were startling. Because she was young. And pretty," the lawyer, who requested his name be withheld to avoid getting in trouble with prison authorities, said.
The lawyer said he witnessed the encounter during a visit to the Manhattan Correctional Center on July 30 — a day after the billionaire paedophile was supposedly taken off suicide watch and transferred to the Special Housing Unit.
Epstein reportedly paid his legal team to sit in a room with him for eight hours a day during lawyer-client meetings so that he could avoid spending time in his cell.
But the woman holed up with Epstein that day had not been in the company of his lead lawyer Reid Weingarten or any of his associates working on the case, the unnamed lawyer told Forbes.
"If I was him, I would have hired … an old bald guy," he said.
The lawyer told the magazine he was at the jail for more than two hours and Epstein and the woman were alone in the room the whole time.
He explained the room was commonly used to facilitate private meetings between inmates and their counsel.
According to procedure, the room is locked when prisoners go in, following the removal of their handcuffs, and unlocked only when they leave and the handcuffs have been put back on.
Epstein's former representatives, including Mr Weingarten, have yet to comment on the latest twist in a case that has gripped America and spawned countless conspiracy theories, including one endorsed by US President Donald Trump.
Instead of dispelling rumours of a staged suicide, the findings of the post mortem examination of Epstein's body — particularly the hyoid injury — have fuelled them further.
Multiple studies from different countries suggest breaks in the hyoid — a small horseshoe-shaped bone near the base of the jaw — are more common in strangulation murders than in suicides.
A 2010 study by the Thai Medical Association titled found hyoid breaks occurred in 25 per cent of cases.
Another study, carried out by US anthropologist in 1992 titled "Hyoid fracture and strangulation", found the bone was fractured in around 35 per cent of victims who had been choked to death.
Though a small bone, it takes a fair amount of force to crack a hyoid, as serial killer Samuel Little revealed in a chilling jailhouse interview with The Cut last year.
"When (Little) talked about the murders, he lit up like a kid on Christmas morning, becoming animated and performing an elaborate pantomime," journalist Jillian Lauren wrote.
"He hugged himself and made kissing noises. With one outstretched arm, he demonstrated just how much force it took to crack a hyoid bone."
New York City Chief Medical Examiner Barbara Sampson released a statement on Thursday cautioning against making conclusions based on any individual findings.
"In all forensic investigations, all information must be synthesised to determine the cause and manner of death," Dr Sampson said. "Everything must be consistent; no single finding can be evaluated in a vacuum."
Epstein's death is under investigation by the FBI and Department of Justice Inspector General.
The 66-year-old was awaiting trial on charges of sex trafficking and conspiracy relating to the alleged sexual abuse of dozens of underage girls in the early 2000s and the operation of a sex slave ring.
Epstein's apparent suicide came less than three weeks after he was found unconscious in his cell, with marks around his neck. He was placed under suicide watch in a special cell with near around-the-clock observation.
But he was removed less than a week later and returned to a special housing unit where he was supposed to be checked every 30 minutes. It has since emerged the prisoner was not checked for several hours on the morning of his death.
Earlier this week, Justice Department officials announced that jail's warden was temporarily reassigned and two guards tasked with watching Epstein placed on leave.
"We are now learning of serious irregularities at this facility that are deeply concerning and demand a thorough investigation," Federal Attorney-General William Barr said.
"This sex trafficking case was very important to the DOJ (Department of Justice) and me personally. FBI and office of DOJ IG (Inspector General) will get to the bottom of what happened and there will be accountability."
WHERE TO GET HELP:
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call police immediately on 111.
OR IF YOU NEED TO TALK TO SOMEONE ELSE:
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