MJF has reportedly suffered a labrum tear, which has raised concerns about whether he will be able to defend the AEW World Heavyweight Championship against Samoa Joe at December's World's End pay-per-view. MJF gave Samoa Joe the title rematch after Joe served as his tag team partner for his Ring of Honor Tag Team Championship defense at Full Gear.

What exactly is a labrum tear and what does the labrum do? Penn Medicine describes it as:

The labrum helps keep your shoulder joint in place. When the labrum tears, you may feel shoulder pain or experience shoulder instability (the feeling that your shoulder is slipping out of place). Labral tears are usually caused by overuse or injury and commonly accompany other injuries to the shoulder.

H/T Penn Medicine

The Penn Medicine site notes there are various treatments besides surgery for labrum tears (depending on the severity o the tear). At this point, it's unknown how severe MJF's injury is.

MJF tweeted:

"I just got an MRI. I tore my labrum in my left shoulder. I'll be defending my title at Worlds End. I believe in AEW,"

The tweet was later deleted

H/T Comicbook.com

Fightful Select's Sean Ross Sapp tweeted:

If MJF is unable to defend the title what then? In the past, AEW has sanctioned interim champions when its champions are unable to defend the title due to an extended injury-related absence. This would mean another interim champion for AEW until MJF returns, at which point he and the interim champion would unify the titles.

WrestleLamia will continue following this story. In the meantime, we send our well-wishes to MJF for a fast and full recovery.