How Serious Are Stress Fractures For NBA Players?

Stress fractures have been quite prominent in the NBA in the last year.

Stress fractures ended the seasons of players like Brook Lopez, Javale McGee, Jrue Holiday and Quincy Pondexter, among many others.

These injuries had major ripple effects on the NBA landscape, as well. The Nets completely turned around their season without Lopez, who went down with a second career stress fracture in his foot in December.

Meanwhile in February, losing Jrue Holiday to a lower leg stress fracture meant a long period of frsutration for the New Orleans Pelicans.

It hasn’t just been the regular season that has been affected by these injuries, either; Alex Len‘s stock in last year’s draft due to an ankle stress fracture, and Thursday’s draft will certainly be affected by the recent news that Joel Embiid has a stress fracture in his right foot, which required surgery on Friday.

Stress fractures are small breaks in bones that result from the accumulation of repetitive stresses on the bone. They are most commonly caused by biomechanical abnormalities, such as high or low arches, rotation of the hips anteriorly or posteriorly, or weakness of muscle groups that result on added stresses to bones.

They are far more common in the legs and feet than the arms and hands, although basketball players can experience wrist stress fractures due to forces from rebounding and shooting.

Essentially, a stress fracture results from inflammation of the outside of the bone breaking down the integrity of the bone itself. This process can go unnoticed for weeks before symptoms present, and by the time they do, the inflammation has usually progressed into a full fracture.

Making things more complicated is that the fractures are commonly small enough that x-rays cannot detect them. If symptoms do present, but no stress fracture is present, it is deemed a stress reaction, or periostitis.

Once a stress fracture is diagnosed, the initial treatment of the injury is the same as the treatment for an acute fracture. The patient is immobilized and if needed, surgery is performed to fixate the fracture. However, because of the biomechanical causes of stress fractures, the rehabilitation often takes much longer, because correcting the abnormalities is needed to prevent reinjury, a common occurrence with these types of injuries. Stress fractures most commonly affect the foot and ankle, although knee, back, and wrist stress fractures are not uncommon.

“Because of the biomechanical causes of stress fractures, the rehabilitation often takes much longer, because correcting the abnormalities is needed to prevent reinjury, a common occurrence with these types of injuries.”

In the NBA, stress fractures have gotten a bad name because of the problems they have caused for some of the league’s best players, particularly centers. Yao Ming had his career ended by consecutive stress fractures to his navicular bone, while Bill Walton‘s career was altered by a string of stress fractures to both feet. However, they are far more common than you may expect, and many players who suffer stress fractures have no issues after the fact.

Blake Griffin‘s missed just four games since a stress fracture in his kneecap ruined what would have been his rookie season, and Zydrunas Ilgauskas had quite the healthy career after getting his stress fracture in his foot surgically fixated.

I dug through 15 years of NBA Injured List transactions, via prosportstransactions.com, and found 61 cases of stress fractures or stress reactions since the 1999-2000 season. This is an incomplete list, of course, as it does not account for players who suffered similar injuries but were listed with more vague terms, and some players were diagnosed during the offseason or college, and would not show up on the list. However, we do have a decent sample size to draw from. Here’s a breakdown of the injuries by body part, and by position:

	Knee	Ankle	Foot	Lower Leg	Back	Wrist	Position Totals
C	0	3	9	4	3	1	20
PF	1	1	4	4	1	0	11
SF	0	0	11	0	0	0	11
SG	1	2	2	3	0	2	10
PG	0	2	3	3	1	0	9
Injury Totals	2	8	29	14	5	3	61 Total Injuries

Bigger players suffered the most injuries, nearly twice as many as any other position group. This makes sense, as the more height and weight a player carries around, the more force is going to be received by the body. As far as injury type, stress fractures by far most commonly affected the feet, with lower leg fractures coming in second. The lower leg also had the highest incidence of stress reactions caught before fractures formed, with 5 of the 14 cases being reactions.

Once I found all 61 cases, I looked at several factors that could help determine the severity of the initial injury. Among these, I calculated the amount of games the players missed through the rest of their career, a far from perfect metric, but convenient way to approximate the affect injury had on a player’s career; reinjury, defined as the suffering of multiple stress fractures to the same area, as was the case with Yao Ming; and future injuries to the same area, which determines how the stress fracture could have had a future effect on injury risk. If you want to peruse the spreadsheet with all of this data, it can be found here.

Games Missed

Back stress fractures had the highest incidence of games missed after the injury, with players appearing in just 50.6 percent of available games after suffering this stress fracture.

Granted, this is skewed by outside major injuries; after all, Shaun Livingston‘s fairly minor stress reaction in his back is outdone by his catastrophic knee injury.

However, players like Matt Bullard and Andrew Bogut have had their careers significantly altered by their back issues, both stemming from a stress fracture. Kneecap fractures have had the least impact on future appearances (81.7 percent of games played since injury), because both players with this injury have been relatively injury-free since.

Foot and lower leg stress fractures are right in the middle, at 67 and 70 percent, respectively. However, foot stress fractures have resulted in the ending of four careers: Chris Mills, Eric Montross, Pavel Podkolzin, and Yao Ming, making them perhaps more significant in this regard than back stress fractures.

Reinjury

Reinjury was surprisingly not a huge issue in any body area, meaning that the stress fractures were usually isolated. However, they were most prominent at the foot, which had five noted cases: Derek Fisher, Zydrunas Ilgauskas, Marko Jaric, Yao Ming, and Brook Lopez.

Ming’s career was ended, and we have no idea what Lopez’s future holds, but Fisher, Ilgauskas, and Jaric were all able to continue their careers after multiple stress fractures. Similarly, the other reinjury cases (Bradley Beal‘s multiple stress reactions, Manu Ginobili‘s multiple ankle issues, and Andrew Bogut’s progression of back stress fractures) have had a scatter-shot of fallout regarding the injury. It seems that while conclusions really cannot be drawn on the effects of multiple stress problems, only 8 of 61 (13 percent) cases suffered recurrent reactions or fractures, so it appears that reinjury is not of great concern when assessing a player with a stress fracture’s future availability.

Future Injury to Affected Area

When it comes to other injuries to the same area, however, stress fractures tend to lead to future problems for the player. Four out of five players who suffered a back stress fracture have seen further complications, from low back soreness to the degenerative disc that ended Matt Bullard’s career.

While other injuries were a factor for these players, back injuries can cause issues elsewhere because they force the athlete to change their biomechanics in order to take pressure off the low back. This could have been a factor for players like Livingston and Bogut.

Meanwhile, in the foot, other injuries are less of an issue than in the back, but are still significant. 31 percent of players who suffered a foot stress fracture had future complications, from ankle sprains to foot soreness. Future stress fractures were the most common injury to occur, but ankle sprains likely are the more common ailment, as they often do not necessitate a move to the injured list, and certainly more than the three noted with IL visits occurred over this span.

Ankle and lower leg stress fractures also led to similar rates of reinjury to foot stress fractures, and ankle sprains caused a majority of future issues. Ankle sprains after stress fractures are common, especially at the ankle, because the ankle’s main mechanism to prevent ankle sprain is the surrounding musculature. The immobilization that is necessary to allow the fracture to heal causes atrophy in that muscle tone, and decreases the ability of the muscles to prevent a sprain. This is why among the future ankle sprains, over half occurred within the first year of returning to play.

Brook Lopez has dealt with many recurring injuries since his first stress fracture in 2011-12: An ankle sprain, a midfoot sprain, and a second stress fracture this past season. /

Overall, players suffering stress fractures since the 1999-2000 season played just 65.9 percent of games over the rest of their careers. They also suffered seven future stress fractures, and 34 percent of the players had future injury to the involved area.

Back stress injuries had the highest incidence of future injury and the highest percentage of future missed games, while foot stress injuries had the highest occurrence of future stress fractures. Based on this information, a player who suffers a stress fracture has roughly a one-in-three chance of having future issues with the injury. That seems like a risk for a team that has to make a decision on a player with a stress fracture, like teams will have to do with Joel Embiid on Thursday.