But is the injury prone label fair? From a rearview standpoint, it certainly is. But the label carries with it the perception that he will continue to be injury prone. Is that fair?
From a statistical standpoint, we’re really limited by sample size. In the past two decades, only a handful of young running backs have been as productive as McFadden despite dealing with significant injury issues. Ricky Williams played in 12 and 10 games his first two seasons, and earned the injury prone label before three straight 16-game seasons. Steven Jackson missed games here and there early in his career, and in fact still has just two 16-game seasons in his career. But Jackson is no longer considered injury prone and has also registered three 15-game seasons.
Fred Taylor resided for years at the intersection of talented and injury prone, earning colorful nicknames like ‘Fragile Fred’ and ‘Fraud Taylor.” He played in only 40 games in his first four seasons, but still scored 37 touchdowns, averaged 4.7 yards per carry, and averaged 106 yards from scrimmage per game. He would play in 16 games each of the next two seasons, before missing games due to injury every other season for the rest of his career.
Cadillac Williams played in 14 games in each of his first two seasons, and things only got worse from there. He played in just 10 games the next two seasons, before playing in 16 games in both 2009 and 2010. Julius Jones missed significant time in each of his first two seasons, but then played in 16 games in each of his next two years. On the other hand, Kevin Jones’s career went 15-13-12-13-11 in terms of games played. Robert Smith was a track star on the gridiron and often seemed as tough as one. In his first two seasons as the starter with the Vikings, he wound up being inactive half of the time each year. In 1997 and 1998, he played in 14 games, but Smith would only play one 16-game season in the NFL: his last one.
But back to McFadden. Let’s start with some baseline about what the anti-McFadden would look like. From 1990 to 2010, there were 91 [1]This excludes Robert Edwards, Jamal Lewis and Terry Allen, each of whom would suffered a season-ending injury prior to the start of the following season. running backs, age 25 or younger, who rushed for at least 1,000 yards and played in 16 games. Only 38 of those 91 running backs (42%) played in 16 games the next season, while the group averaged 13.9 games played in the following year. The median was 15 games played, with 58% of running backs playing in 15 or 16 games.
Let’s work with some fuzzy math. [2]Not a technical term. The 91 running backs in Year N+1 had 27,132 carries and 3,732 receptions. Let’s assume a player is only half as likely to get injured on a reception as a rush, so we can convert the 27,132 carries into 28,998 adjusted carries. Continuing with the assumptions, let’s assume that for the 53 running backs who missed games in Year N+1, all missed games were due to exactly one injury [3]This is obviously not true, as some running backs missed games due to multiple injuries. On the other hand, some running backs entered the season with a pre-season injury or missed a game for … Continue reading. Working off those numbers, we would conclude that for talented, young, non-injury prone running backs (“TYNIPRB”), the injury rate would be 1.8 injuries per 1000 adjusted carries.
What would be the odds of McFadden getting hurt last season after 123 adjusted carries if he was a TYNIPRB? There is an 20% chance he would get hurt simply by random chance. There would be a 36% chance of him getting hurt after one of his 247 adjusted carries in 2010 even if he was a TYNIPRB. Going back to his earlier years, there was a 19% chance of injury for him in ’09 and 21% in 2008 based on his number of adjusted carries. Add it up, and the odds of him getting hurt each and every season just by pure (bad) luck would be 1 in 345.
Now remember, that 0.18% injury rate was derived from fuzzy math (and that label is probably too generous). If the rate was 0.30% — i.e., if you think running backs are likely to get hurt on every 333 carries instead of every 556 carries — a TYNIPRB with McFadden’s adjusted carries history would have a 1 in 66 chance of getting injured in each of his four seasons. On the other hand, if the rate was 0.1%, the likelihood of a TYNIPRB missing time each year would be just 1 in 3019. So figuring out the exact injury rate is certainly a vital part of the question. [4]Perhaps an even more important part, but outside the scope of this article, is that carries are not really independent events. There has been some great research by Jason Lisk showing that repeated … Continue reading
As regular readers know, this is also a “What are the Odds of That?” question. Some running backs every year are bound to get injured, and we know some will get injured multiple years in a row. If each of the 32 teams commits to one starting running back for four consecutive years, and 13 running backs each year miss time due to injury, then there is a 59% chance at least one running back will be injured each of those four years simply be random chance. If we assume that 19 of the 32 running backs will miss time — which is consistent with the TYNIPRB data — there is a 99% chance at least one running back will get injured each of those four seasons despite having the same injury rate as everyone else.
But as much as it would be nice for math to help us, I don’t know if it can do much more than provide some boundaries for our own opinions. Each running back injury is different, and no two running backs are like. As a rookie, McFadden dealt with a turf toe injury on his right foot, and then missed three games with turf toe on his left foot. In 2009, McFadden tore the meniscus in his knee and missed a month of football. Two years ago, he missed two games with a hamstring injury and was listed as questionable but did not play in week 17 due to turf toe. Then last year, a Lisfranc injury ended his season after seven games.
Are those injuries fluky? Are they the type of injuries that are more likely to take down injury-prone players? Are they the type of injuries a tougher or more mature (i.e., McFadden in 2012) player could play through? These are all important but difficult questions to answer. And I don’t have any answers to those difficult questions.
But I enjoy thought exercises. Ask yourself this one: who is the least injury prone running back in the NFL? Only one running back — Chris Johnson — started 48 games the last 3 years [5]To be fair, Ray Rice has played in all 48 games, too, but lost three starts to Willis McGahee in ’09 and ’10. Johnson is also the only running back to start 32 games the last two years. Does Chris Johnson feel like a safer bet to play in 16 games this year than McFadden? Do Ray Rice or LeSean McCoy strike you as significantly more likely to avoid injury?
If Vegas offered odds on Chris Johnson playing more games this year than Darren McFadden, what would they be? My gut tells me Vegas would consider Johnson a favorite, but not an overwhelming one. McFadden has struggled with injuries, and odds are he probably is more injury prone than unlucky. But when it comes to running backs, I don’t know how much that means for the future. And I don’t know if we’ll ever be able to say anything more definitive than that.
Previous “Random Perspective On” Articles:
AFC East: Buffalo Bills, Miami Dolphins, New England Patriots, New York Jets
AFC North: Baltimore Ravens, Cincinnati Bengals, Cleveland Browns, Pittsburgh Steelers
AFC South: Houston Texans, Indianapolis Colts, Jacksonville Jaguars, Tennessee Titans
AFC West: Denver Broncos, Kansas City Chiefs, Oakland Raiders, San Diego Chargers
NFC East: Dallas Cowboys, New York Giants, Philadelphia Eagles, Washington Redskins
NFC North: Chicago Bears, Detroit Lions, Minnesota Vikings, Atlanta Falcons
NFC South: Atlanta Falcons, Carolina Panthers, New Orleans Saints, Tampa Bay Buccaneers
NFC West: Arizona Cardinals, San Francisco 49ers, Seattle Seahawks, St. Louis Rams
References
↑1 | This excludes Robert Edwards, Jamal Lewis and Terry Allen, each of whom would suffered a season-ending injury prior to the start of the following season. |
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↑2 | Not a technical term. |
↑3 | This is obviously not true, as some running backs missed games due to multiple injuries. On the other hand, some running backs entered the season with a pre-season injury or missed a game for non-injury reasons, so maybe this evens out. My guess is that this cuts against McFadden, as it makes it seem like injuries happy less frequently than they actually occur. |
↑4 | Perhaps an even more important part, but outside the scope of this article, is that carries are not really independent events. There has been some great research by Jason Lisk showing that repeated carries over short time frames are correlated with higher injury rates. |
↑5 | To be fair, Ray Rice has played in all 48 games, too, but lost three starts to Willis McGahee in ’09 and ’10 |