Time was when a torn anterior cruciate ligament meant your career was over. At best, it was far different. As Bernard King can attest to, torn ACL’s weren’t understood, well treated, or even properly diagnosed. Bad knees were bad knees. Your knee didn’t stop hurting, you got taken out back and shot. That was the last time you ever used the knee.

However, the 21st century, with its flying robot cars and jetpacks for all, is a very different place. Advances in medical science, and a more important concurrent awareness of these advances, have led to enlightened times. Now, a player can tear an ACL and still play.

There is no greater testament to this than the fact that, as best as I can ascertain, 18 players currently in the NBA have previously had torn ACL’s surgically repaired.

That number does not include Ricky Rubio and Eric Maynor, promising young guards who tore ACL’s earlier this season. It does not include Derrick Rose and Iman Shumpert, who tore their ACL’s earlier this week. It also does not include the dozens of others in the recent history of American professional basketball to have had the surgery — of which a non-exhaustive list can be found here — nor does it include the hundreds of NFL players, other sportsmen, or those of us in every day life. Now that we’ve learned (and been bothered) to diagnose it properly, it turns out the injury is rather common.

You can play again after tearing your ACL. In fact, you can even play without having any at all.

The more pertinent question is to what standard you can play. The proliferation of torn ACL’s does not make the injury any less severe. No two ACL tears are the same, nor are any two victims, if that’s the right word. You can’t compare Adam Morrison’s athleticism after his ACL tear to Derrick Rose’s before his, not unless you were playing the Opposites Game. (And if you were, you’d win.) To find a median, then, we ought perhaps look at the aforementioned 18 and try to establish some precedent.

Some players come back just as good they were before the tear. Even though he also tore his MCL and meniscus at the same time, Nene retained his agility after his 2005 triple tear, and became a better player than he ever was before. The same could be said of Shaun Livingston, although we’ll never know quite what he could have been. Similarly, Al Harrington tore his ACL in 2002 in the middle of his break out campaign, came back, and then broke out again anyway. Jared Jeffries actually got better after his rookie season injury, before becoming what he is today. And after tearing his ACL in a 2005 preseason pickup game, Willie Green has demonstrated in the seven years hence that he is as staggeringly mediocre as ever.

On the flip side, look at what has become of Michael Redd, Leon Powe and Nenad Krstic. Powe and Redd’s injuries led to further re-injuries, whilst Krstic’s days as one of the league’s best young centers were emphatically ended by his. And while Josh Howard’s decline could be attributed to both a lengthier injury history, age and chronic tendinitis, the post-ACL tear Howard is half of what he was.

Some of the more recent ACL success stories are big men. Currently playing 29 mpg in the playoffs, David West just played a full 66-game season after tearing his ACL as recently as last March, and still has as much athleticism as before (that is to say, not a lot). To tear an ACL and miss only 11 games, lockout assisted or not, is a testament to the improved prognosis you get these days. Similarly, Al Jefferson is just as grounded and productive as he was before his tear three years ago, Jason Smith lost none of his fluid athleticism, and while he can only receive an “incomplete” grade at this stage, after missing all of last season, Jeff Pendergraph is nonetheless back.

The most comparable players to Rose (and, to a slightly lesser extent, Shumpert) are, of course, athletic guards. It’s great that Pat Garrity came back and was still able to dunk on Sam Dalembert, but it doesn’t really allude to what may happen to Rose, whose athleticism is more important than his skills.

Inevitably, there are fewer comparisons for this. There just aren’t that many guards with elite athleticism — after all, if there were, it wouldn’t be elite. Even athletic players such as Brandon Rush, Jamal Crawford (who maintains that his knee was actually better after the tear) or Corey Brewer — who can still do this after his ACL tear, yet doesn’t jump off his bad knee anyway — don’t use their athleticism in the same manner. Nor does someone like Tony Allen, a powerful athletic guard with a build akin to Rose, but without the other-worldly ability to change direction. Almost incomparably athletic players are almost incomparable.

There do, however, exist a few similar circumstances. Two favorable, one not.

First, the not. Tim Hardaway tore his ACL at the end of his fourth season, and missed the whole 1993-94 campaign as a result. When he returned, he still put up 95 percent of his previous statistical output, but without the same level of explosiveness. The three-point attempts spiked, the athleticism waned, and, while still very good, Hardaway noticeably lost a bit. This all happened two decades ago, and matters have advanced since then, but with so few comparisons available, Hardaway’s lost explosiveness is noteworthy.

Conversely, two exceptionally athletic guards — Baron Davis and Kyle Lowry — tore their ACL’s in their college years, and yet you wouldn’t know it. Until Rose and Russell Westbrook came along, Davis was the template for the perfect point guard physical specimen, and if Lowry trails them in that department, it’s not by much. In no apparent way did their injuries affect their athletic abilities or career projection — Davis reached All-Star status, while Lowry continues to climb. Whatever they lack as players, the ACL tears are not to blame.

There is no way of knowing what will happen to Rose, Shumpert, Rubio and Maynor. So, given that we don’t know, we have to imagine what will happen. We can be safe in the knowledge that, in multiple recent cases, the player lost nothing at all. More often than not, in fact.

With this in mind, why foresee anything less than a perfect prognosis?