There is one injury that can thwart both an all-star pitcher with the Chicago Cubs and a teen practicing to make the varsity team: a torn labrum. A piece of fibrocartilage in the shoulder, the labrum cushions the top arm bone, the humerus, against the socket known as the glenoid. Having it securely in place is vital for throwing, and requires surgery to remedy.
“The labrum is a pretty simple stabilizer to the shoulder joint,” explained John D. Kelly IV, a professor, surgeon, and the director of Sports Shoulder at Penn Medicine. “It creates a suction seal. It’s like an O-ring on a valve.”
Slate proclaimed the labrum tear as baseball’s “most fearsome injury,” and rightfully so. About half of major leaguers don’t return to form.
But some do. Trevor Hoffman was in the middle of his career as a star relief pitcher with the San Diego Padres when he tore his labrum and had surgery. He returned to be just as dominant and ended up in the Hall of Fame.
And a current example of a thrower excelling after the injury (and surgery) is in a different sport: football.
Andrew Luck missed all of the 2017 season due to a multitude of injuries, chief among them a labrum he tore in 2015. Now, the Indianapolis Colts quarterback is on pace for a career-high in touchdowns.
So why are labrum injuries career-killers for some but just a bump in the road for others?
All of the force generated by an arm whipping around to throw a ball goes through the shoulder joint. If the labrum isn’t sealing right, there could be instability, which translates to pain and a dip in performance.
But instability isn’t just related to pain.
“Stability provides proprioception, or knowledge where the arm is in space,” said Kelly. “It also lets the athlete subconsciously know where exactly to place the ball by the feedback it provides to the brain.”
Read more at Penn Medicine News Blog.
