"It's been a long process," Billingsley said.
Billingsley is 13 months removed from a reconstructive elbow operation commonly known as Tommy John surgery. He still doesn't know when he will pitch in a major league game.
Chris Withrow could soon find himself in a similar predicament. The hard-throwing Dodgers reliever was diagnosed with a torn ulnar collateral ligament last week and was advised by team physician Neal ElAttrache to undergo Tommy John surgery. Withrow will get a second opinion next week.
Billingsley is part of a fraternity that is growing at an unprecedented rate, as the number of Tommy John operations performed on major league pitchers has significantly increased in the last three years.
There have already been 20 major league pitchers to have the procedure this year. That number could increase to 22 if Withrow and Angels reliever Sean Burnett decide to have it too.
Stan Conte, the director of medical services for the Dodgers, doesn't know why this is happening.
"I may be the only one who doesn't have a theory," Conte said.
Conte has conducted numerous studies on injuries. What he found was that in the 15 years leading up to 2012, an average of 16 Tommy John operations were performed on major league pitchers every year. That figure soared to 35 in 2012.
Only 18 such procedures were performed last year, making Conte think 2012 might have been an anomaly. Then came this year.
"The thing that is worrisome is that when you look over 14 or 15 seasons and when they occur during the year, the month they occur the most is June," Conte said. "We're not in June yet. I don't know what's going to happen in June."
Conte thinks a variety of factors could be responsible for the trend.
•Pitches are throwing harder than ever. "The higher the velocity, the more stress on the ligament," Conte said. "If people continue to throw harder, what you end up doing is you pitch beyond the ability of the ligament to hold the elbow together. You can strengthen muscles, you can increase flexibility, you can improve biomechanics, but you can't strengthen a ligament."
•The proliferation of year-round youth baseball, which results in pitchers throwing too much too soon. Plus, Conte said, "Everybody's fixated on radar guns, including scouts. If you have a pitcher who pitches really well and gets everybody out in high school, but throws 78 mph, what's the chance of him getting drafted?"
Then again, none of this is new.
"Why now?" Conte said. "I don't know. And the people who say they know, you probably have to moonwalk away from them."
Conte doesn't subscribe to the idea that it's unnatural for human beings to throw overhand.
"It is not an unnatural act," Conte said. "Your shoulder is designed to throw. But is the shoulder designed to throw 100 mph 100 times in two hours?"
As for a solution, Conte said, "If a pitcher never pitches, he'll never get hurt. But the fact is, that's what they do, and that is a risky thing in regards to injuries."
The recovery process, as Billingsley is learning and Withrow could find out, also remains an inexact science.
Tommy John surgery is largely effective, as Conte said three-quarters of major league pitchers who have the procedure pitch in the major leagues again. Still, that means 25% never make it back. Conte said there are misconceptions that pitchers generally return in 12 months — it often takes longer — and that they return throwing harder.
The road back is different for each individual pitcher.
In the case of Billingsley, he didn't have any significant setbacks throughout the winter and spring. By early April, he was ready to pitch in a minor league game.
It was in that start that he felt something in his elbow.
"I had the scar tissue break up and got a little bit of tendinitis," Billingsley said.
He was shut down for a few weeks, after which he resumed the process of building up his arm.
"It's been a long time," Billingsley said. "It's been 13 months. That's a long time to not be able to play in a game. I don't really feel like a baseball player. Today, I felt like it a little bit, actually seeing a hitter in there."