What is Tommy John surgery? How long does it take to recover from this procedure?

Tommy John surgery is a term that conjures fear and anxiety among some of the best pitchers in the MLB. While many fans may be familiar with the term, few are aware of the actual process.

Tommy John surgery (TJS) is one of the most common long-term ailments suffered by pitchers and each year, between seven and ten big league starters are required to undergo this arduous procedure.

"Bryce Harper ended up having Tommy John surgery today and could be back in mid-May, per @JSalisburyNBCS" - @ FOX Sports: MLB

It is named after the popular pitcher Tommy John, who was a pitcher for the Los Angeles Dodgers and New York Yankees, among others, over his 26-year career that spanned from 1963 to 1989.

During the 1974 season, John was leading the MLB in winning percentage for the third straight season when he tore his ulnar collateral ligament. In the blink of an eye, his promising career now stood in the balance.

The ulnar collateral ligament (UCL) is a tendon in the elbow., which is instrumental in the act of throwing a baseball. Without it, it is virtually impossible to throw with any power.

After his injury, Dodgers physician Frank Jobe performed a revolutionary procedure that replaced his UCL with a tendon from his forearm. Remarkably, John made a full recovery and went on to pitch for another 15 years in the MLB

"I need Tommy John surgery after watching this" - @ Baseball

Although the UCL is usually replaced by the right arm tendon, Tommy John surgery patients have also had their UCL replaced with tendons from their legs, such as hamstring or patellar tendons.

Notable MLB players who have undergone this procedure include Jacob deGrom, Yu Darvish and Johnny Cueto. To date, the oldest player to undergo the procedure was then-Philadelphia Phillies pitcher Jamie Moyer, who was 48 at the time of his surgery in 2010.

TJS is a taxing procedure that usually takes several months to recover from. However, it has revolutionized baseball as it means that pitchers no longer have to tie their fate to their UCL.

Tommy John surgery cases on the rise

According to the Journal of Shoulder and Elbow Surgery, the incidence of players needing to undergo the procedure has gone up three times in the past 20 years, and is thought to increase more. This is because pitchers are now throwing faster and harder with their arms under more pressure than ever before.