Are pitchers getting hurt more often?

News item: Yu Darvish has partially torn ligaments in his right elbow, and a decision will be announced later this week whether he'll undergo Tommy John surgery.

Modern baseball has been barreling toward this moment for the past 20 years, and it’s not going away anytime soon. All of the perils that harmed the current generation -- overuse as children, max-effort delivery on every pitch, increasing velocity, poor training methods, moral hazard among adults tasked with handling kids -- have, if anything, gotten worse. There won’t be a day when every pitcher wears a zipper scar on his elbow. But the ones who don’t will be the lucky few.

Darvish’s injury reinforces the susceptibility of every pitcher and is yet another sounding of the clarion call that goes ignored again and again. For baseball to slow down the prevalence necessitates a top-to-bottom overhaul of its development structure.

--Jeff Passan, Yahoo Sports

So is this strictly overuse?

Right. We found out that the ones who had surgery tended to be the ones who would throw more than 80 pitches in a game, the ones who pitched more than eight months per year. Again, this was 15- to 20-year-old kids. The pitchers who have surgery were almost always the ones who kept pitching when they were fatigued.

The basic problem is that too much pitching leads to injuries. People ask me all the time, "Is pitching natural?" I would say that excessive pitching, throwing 100 full-effort pitches every fifth day, is not natural.

If you’re young?

No, for anyone. In the history of humans and anatomy, we weren’t born to pitch 100 full-effort pitches every fifth day. Throwing is natural; throwing excessively is not natural. And so, basically, you want to avoid too much competitive pitching, but also avoid too little. They should be throwing, but also playing multiple sports as kids.

--Dr. Glenn Fleisig, research director, American Sports Medicine Institute, in Q&A with Grantland's Jonah Keri

Jeff's column and Dr. Fleisig's research suggest the same thing: What happens when you're playing baseball as a kid or teenager is likely to have a major impact on your elbow when you're in your 20s and in the majors -- if you even survive to that point with your ulnar collateral ligament intact.

In Jeff's piece, he refers to the "arm epidemic plaguing baseball." The headline on Jonah's Q&A calls out the "Tommy John Epidemic." An epidemic suggests a widespread prevalence. Jonah's piece reports (citing a "Sport Science" feature on ESPN) that there were more Tommy John surgeries in 2014 than the entire decade of the 1990s. As Dr. Fleisig points out in the interview, some of those surgeries are the result of improved technology to detect the injuries, but the inference is that we're seeing more injuries than before, with the accumulating evidence that too many pitches as a youth and perhaps too many max-effort 95-mph fastballs as an adult are significant factors.

But are we seeing more injuries than before? And when does "before" refer to? It's impossible to know the answer to that, since we don't have a database of injuries that goes back to the 1990s, let alone the '80s and '70s. But we can dig into the sport's history and try to uncover some trends.

Here's what I did, in an admittedly imperfect study. With the help of Baseball-Reference.com's Play Index and search function, I went back to 1970 and counted how many pitchers made 30-plus starts each season. You can argue with this method. In the 1970s, some teams still used four-man rotations at times, so there were fewer rotation slots overall. On the other hand, starters had the chance to start more games in a season, so could miss some time and still meet the 30-start standard. In general, however, if you made 30 starts in a season, you made it through the season in one piece, and that's what I was trying to track.

From there, I checked how many of those pitchers made at least 30 starts again the following season and if they made 30 in Years 3, 4 and 5 following the first year. For example, the Year 5 for our 1970 subset of pitchers would be 1974, 1971 tracks out to 1975 and so on. Healthy and productive starters will keep making 30 starts a season; of course, we would expect natural attrition due to old guys who retire or flame out or others who weren't good enough to stick in rotations. (Note: The strike seasons of 1981, 1994 and 1995 affect the data in some cases, so it is ignored as necessary.)

Average number of starters per team making 30 starts:

1970-1974: 2.48

1975-1979: 2.38

1980-1984: 2.38

1985-1989: 2.45

1990-1994: 2.27

1995-1999: 2.37

2000-2004: 2.32

2005-2009: 2.45

2010-2014: 2.33

I'd say that's a pretty constant rate. Even with the rash of Tommy John surgeries, teams have managed to do a good job of keeping starters healthy at a rate in line with historical trends. This is probably a credit to modern training staffs as well as the emphasis on pitch counts the last 15 years or so that helps keep pitchers healthy throughout the season. This rate has remained constant even though teams now often manipulate the service time of rookies by holding them back in the minors to start the season or are more willing to shuffle pitchers in and out of the rotation than in the past.

Percentage of starters making 30 starts the next year

1970-1974: 67 percent

1975-1979: 58 percent

1980-1984: 58 percent

1985-1989: 58 percent

1990-1994: 62 percent

1995-1999: 57 percent

2000-2004: 55 percent

2005-2009: 58 percent

2010-2013: 56 percent

Again, pretty consistent rates, but a few notes here. The late '60s and early '70s were a pretty unique time, a low-scoring era in which many pitchers threw extraordinary totals of innings, the most seen on a routine basis since the dead ball era. Remarkably, many of those pitchers had long and productive careers -- Gaylord Perry, Steve Carlton, Nolan Ryan, Mickey Lolich, Phil Niekro, Tom Seaver, Don Sutton, Ferguson Jenkins and so on. Since 1920, there have been 150 seasons where a pitcher threw 300 innings; 40 of those came in a seven-year span from 1968 to 1974 (27 percent of those 150 seasons).

Anyway, with offense down, it would make sense that more pitchers would be able to maintain a spot in the rotation the following season. Or you could argue that offense was down because of a special generation of pitchers who managed to remain healthy from year to year. Some have argued that the generation of pitchers listed above reached the majors in the late '60s, before the mound was lowered in 1969, starting their careers when pitching from a high mound perhaps didn't put as much strain on their arm, or because the high mound and big strike zone made pitching "easier" and thus less damaging to their young arms, and thus helping lead to longer careers down the road. An unprovable but reasonable hypothesis.

We get another little spike in 1990-1994, although that span includes only three seasons of data, 1990 to 1992, due to the 1994-95 shortened seasons. Those three years were another low-scoring era before offense began increasing in 1993. Those numbers are helped by the 1991-1992 seasons, when 43 of 57 pitches who made 30 starts in 1991 did so again in 1992 (75 percent, the highest of any year-to-year percentage in the study).

We get a little dip in 2000-2004; the steroids era wasn't good for pitchers. As to where we're at now, we have seen a slight decline in the raw number of pitchers making 30 starts in recent season, and that perhaps is a reflection of the increase in Tommy John surgeries:

2005: 78

2006: 76

2007: 71

2008: 75

2009: 67

2010: 74

2011: 73

2012: 65

2013: 69

2014: 68

Percentage of starters making 30 starts in Years 1 through 5

1970-1974: 23 percent

1975-1979: 24 percent

1980-1984: 15 percent

1985-1989: 15 percent

1990-1994: Incomplete data due to strike years

1995-1999: 13 percent

2000-2004: 17 percent

2005-2009: 14 percent

2010-2014: 19 percent (2010 only)

Entering 2015, we have a group of 17 pitchers going for their fifth consecutive season of making 30 starts. If they all succeed in doing so, that would be the highest total of "five in a row" seasons in the study (1970-1974 and 2009-13 both had 16). The 2012 group has 21 pitchers working on three consecutive 30-start seasons. In this regard, I'd argue baseball is keeping more pitchers healthier than ever before.

Percentage of starters making 30 starts in Year 1 and Year 5

1970-1974: 37 percent

1975-1979: 38 percent

1980-1984: 35 percent

1985-1989: 35 percent

1990-1994: Incomplete data due to strike years

1995-1999: 36 percent

2000-2004: 36 percent

2005-2009: 31 percent

2010-2014: 35 percent (2010 only)

I was curious to see how many starters made 30 starts in Year 1 and then again in Year 5, not necessarily nonconsecutive. I thought this number might be increasing as modern medicine -- Tommy John surgeries and otherwise -- helps get more pitchers back on the mound, or a more cautious approach to sore elbows and shoulders prevents serious damage.

But the numbers aren't much different than the 1970s, when pitchers were told to put some ice on their sore elbow and suck it up. My theory as to why: better competition. There are more good pitchers than ever before, so it's more difficult to hold on to a job. (Also, since minor leaguers are monitored more closely than 20 or 30 years ago, more of them are arguably reaching the majors before getting injured, thus creating even more competition.)

* * * *

OK, that's a lot of data. I wasn't setting out to prove anything here. It certainly seems possible, as Jeff Passan and Dr. Fleisig both suggested, that if MLB (and the Japanese major leagues) can work more closely with amateur baseball to create more preventative measures for pitchers before they turn pro that pitching injuries -- in conjunction with all the modern advantages of medicine, training techniques, biomechanics and usage patterns -- have a chance of being reduced.

Are we in the midst of an epidemic, though? I'm not sure I'd use that label. As Dr. Fleisig says in that quote above, "Pitching is not natural." There's nothing historically unique about the year-to-year changeover in pitchers we're seeing now. Pitchers have always gotten hurt, and they always will get hurt. Of course, you can argue that an increase in elbow injuries and resulting Tommy John surgeries cancels out improvements made in other areas in keeping pitchers healthy, and that if baseball finds a way to limit the elbow injuries, more pitchers will remain healthy and productive.

You could also suggest teams find more Mark Buehrles, but he's more exception than rule. You can tell pitchers to stop worshiping the radar gun, but good luck there when velocity leads to bigger draft bonuses or college scholarships or better results in the majors. As Dr. Fleisig told Jonah regarding injuries, "Velocity is a factor. All things being equal, throwing 95 mph is more stressful than throwing 90. But throwing 95 mph with good mechanics is less stressful than throwing 90 mph with bad mechanics."

One reason we arguably had as many injuries in the 1970s as now even though pitchers didn't throw as hard is probably related to the less polished mechanics (in general) of the era. I'm also reminded of something John Smoltz said this winter, that he never felt like he was maxing out in his delivery. That sounds like good advice, but even Smoltz still underwent Tommy John surgery, when he was 33.

There is no easy fix here. We can only hope that Darvish eventually returns, that Jose Fernandez returns, that Matt Harvey is lights-out again now that he's back. But until they force pitchers to throw underhand, I fear Tommy John's name is going to remain in the news.