Ryan Zimmerman is one of 61 all-stars who have spent time on the disabled list this season. Teammates Bryce Harper (thumb) and Gio Gonzalez (shoulder) are also in that group. (Jonathan Newton/The Washington Post)

Two weeks ago, the Washington Nationals welcomed to Nationals Park the star-studded Cincinnati Reds, who employ four-time all-star and 2010 National League MVP Joey Votto at first base. Yet Votto never appeared in the District and instead rehabilitated his injured left leg. In the middle of the series, the Reds put Votto on the 15-day disabled list, where he remains.

Last week, the Miami Marlins came through town — without star right-hander Jose Fernandez, because the 2013 NL rookie of the year is done for the season following elbow surgery. This weekend, the Texas Rangers are in the District, with fill-in Mitch Moreland at first base rather than Prince Fielder, a five-time all-star who won’t play again this year because of neck surgery.

“Baseball doesn’t stop for injuries,” Marlins Manager Mike Redmond said. “It doesn’t give you a week off to feel sorry for yourself. You play every night. You got to keep moving.”

The movement this year, though, seems particularly difficult given how many prominent players have been hurt. Through Saturday afternoon, just as the season completes its second month, no fewer than 61 current and former all-stars had made at least one trip to the disabled list — an average of more than two per team. The first round of all-star balloting was released last week, and if the game was played tomorrow, two projected starters — Colorado third baseman Nolan Arenado and Baltimore catcher Matt Wieters — wouldn’t be able to play because of injuries.

“It is a lot,” said Rangers Manager Ron Washington, whose club has put a league-high 17 players, including five all-stars, on the disabled list. “It’s definitely out of the ordinary.”

In reality, such a story line is mostly anecdotal, gathered intuitively by glancing at the transactions and listening to the daily reports of one star or another coming up lame. League-wide injury trends toggle in one direction or another. According to data compiled by Jeff Zimmerman of the Web site FanGraphs.com, major leaguers spent close to 30,000 days on the disabled list in 2013, the most over the past decade, and days on the disabled list had increased every year since 2010. But the trend in the previous three seasons was downward — again, approaching 30,000 in 2007 but fewer in the subsequent two years.

“It’s a very complicated question,” said Gary Green, Major League Baseball’s medical director. “We look at all of the injuries, but you can’t lump in all the injuries as the same. They have different causes. Even within certain injuries, there are different reasons. Someone who has a heart attack might have a heart attack for a different reason than someone else: He’s a smoker or has high cholesterol or a family history. We’re all looking at the end result, but we have to look at more than that.”

Indeed, it’s impossible to link the injury suffered by San Francisco right-hander Matt Cain, who cut his finger with a knife while making a sandwich, with the injury suffered by Red Sox first baseman Mike Napoli, who broke his finger sliding into second. (Cain returned to the DL on Saturday with a strained right hamstring).

Two of the ailments that have hindered the Nationals — thumb injuries to outfielder Bryce Harper and third baseman Ryan Zimmerman, both suffered while sliding — would seem to fall into the hard-to-prevent category.

“A hamate and a broken thumb and a torn ligament from sliding into a base — those are freak things,” said Manager Matt Williams, referring also to a broken wrist bone suffered by catcher Wilson Ramos. “I think for the most part we’ve been really good. We haven’t had the things that you could attribute to lack of working out or lack of attention to detail.”

Yet are common injuries — muscle strains and the like — really the result of a lack of attention to detail? The truth is, baseball doesn’t know. So Green and MLB are trying to gain a better understanding of the nature of injuries in the sport so they can better treat and prevent them. The league began tracking injuries across the majors only in 2010, and it only has full data from the 2011-13 seasons. For now, understanding the frequency of specific injuries — and the causes of those injuries — isn’t possible. But it’s coming.

“Like with everything, we’re hoping to learn more,” Green said. “We’re hoping we learn new things every year, and those things will help us help the safety of players at all levels.”

Green said MLB’s “electronic health records” system will include not only medical histories for players in the majors but chart injuries for roughly 7,000 minor leaguers as well.

The creation of such a database could help reduce some of the mystery around some injuries. The Rangers, for instance, have been hurt both by Fielder’s neck injury and a back problem for right-hander Matt Harrison, surprises for which there was no warning.

“There were injuries there we couldn’t do nothing about,” Washington said. “Undoubtedly, there were injuries that were dormant. Sometimes, you wish you were Superman and we could look right through you and see if there was something there, but you can’t.”

There is, too, an increasing focus at lower levels of the sport. No injury has been more prominent this season than elbow ligament replacement surgery — commonly known as “Tommy John surgery” — for major league pitchers. Last week, the American Sports Medicine Institute issued a “position statement” on the injuries, which the group calls an “epidemic.” And the focus wasn’t on the major league level.

“There’s a lot going on in youth baseball, where they’re pitching a lot and pitching year-round, where they’re just riding these ligaments into the ground,” said Tony Laughlin, a biomechanist at ASMI. “Then they make it up to the pro level, and they throw it up to another level — higher volume, greater frequency, throwing at [higher speeds]. . . . We want the focus to be for parents and younger kids to give their arms a rest.”

But for the all-star pitchers already down for the season — Fernandez, Arizona’s Patrick Corbin, Matt Harvey of the New York Mets, Tampa Bay’s Matt Moore among them — that message comes too late. And that all means that the number of attractive story lines for baseball to present as summer approaches isn’t what it might be.

Hey, the Brewers are in town. Wait, Ryan Braun’s out of the lineup? Am I going to turn it on, much less go?

“In baseball, there’s a one-on-one going on all the time between the pitcher and the batter that you always have,” said Pete Macheska, the coordinating producer for MLB on Fox, which broadcasts a game of the week each Saturday. “Say Prince Fielder’s not playing. He only comes up four times anyway. There’s 27 outs. You’re not going to find where you’re talking about him continually. In a basketball game, LeBron James is always on the court, say for 42 of 48 minutes or whatever. Baseball is different.”

Not to mention that the season is just now two months old. There’s no telling whether the number of days on the disabled list will increase for a fourth straight season. But as he fielded a lineup against the Rangers that was without Zimmerman and Harper, with left-hander Gio Gonzalez hoping to make it back from a shoulder issue, Williams could look across the dugout at Nationals Park and know that moaning about fallen stars will do no good.

“We’re not alone,” he said. “We know that.”