New Jersey woman, 21, gets her jaw stuck wide open after YAWNING too hard - and team of ER doctors have to 'manually' shut it

A woman yawned so hard that her jaw became physically locked open, sending her to the ER where doctors had to manually shut it.

Jenna Sinatra, 21, from New Jersey, suffered the freak accident this week, just days before her birthday, and documented her trip to the hospital in a now-viral TikTok video.

Doctors told her that she dislocated her jaw, which caused the joints responsible for her mouth opening and closing to become locked in place. This prevented her from closing her mouth all the way. 

The injury, which lasted for several hours, took doctors four hours to fix by giving her muscle relaxing medications and 'shoving' her jaw back together. 

'Only something like this would happen to me,' she wrote in the caption of the video, which has been viewed 7.4 million times.

Jenna Sinatra, 21, posted a series of TikTok videos after her jaw became stuck open from yawning. It took doctors four hours to 'manually' shut her mouth

Ms Sinatra, an influencer with 2.3 million TikTok followers, got her jaw stuck open just days before her 21st birthday

Dr Anthony Youn, a plastic surgeon in Michigan, stitched Ms Sinatra's video and described the phenomenon as 'open lock,' which leaves the jaw 'literally stuck open.'

'This is very rare, but when it occurs, it often happens after somebody does a big yawn,' he said in his response, which got 3.2 million views. 

In Ms Sinatra's case, her jaw became dislocated, which is when two bones in one of your joints separate. 

In this case, the joints connecting Ms Sinatra's jaw and skull separated. 

It's unclear exactly what caused Ms Sinatra's yawn to go wrong, but major risk factors include being double-jointed, grinding your teeth, or having arthritis.  

The condition is medically known as a TMJ disorder, which involves the joints connecting the jawbone to the skull, almost like sliding hinges that allow you to open and close your mouth. 

While most people with this issue have lockjaw, which keeps the mouth closed shut, in 'rare' cases, TMJ injuries can leave the mouth hanging open.

An estimated five to 12 percent of Americans have had their jaw locked at some point, though it's unclear how many have had it stuck open. 

Previous jaw injuries, arthritis, and teeth grinding or clenching have been shown to increase the risk of TMJ disorders.

After several hours of home remedies, Ms Sinatra eventually had to go to the hospital, where doctors discovered that yawning dislocated her jaw

Dr Anthony Youn, a plastic surgeon in Michigan, described the phenomenon as 'open lock,' which often happens after yawning. He noted that her jaw could have been dislocated from a TMJ disorder

Dr Youn said that an open lock like Ms Sinatra's is usually treated with muscle relaxing medications and 'manual adjustment.' 

Ms Sinatra did not specify which medications she was given, but common muscle relaxants include carisoprodol (Soma), methocarbamol (Robaxin), and tizanidine (Zanaflex).

This may involve massaging the joints, putting heat or ice on them, loosening muscles with injections, or using Botox. These help the joints become looser and less stiff, which allows them to come back together.

Ms Sinatra eventually recovered from open lock, though she posted videos of her having to wear bandages wrapped around her entire head for her birthday dinner.