NBA style of play, researchers link to knee injury | Information Center


The more a professional basketball player directs the ball toward the basket to score, the higher the risk of the dreaded knee injury known as an anterior cruciate ligament tear, according to a Stanford Medicine study.

While this should come as no surprise to basketball fans whose favorite players suffered the injury, including the Golden State Warriors Klay thompson at the 2019 National Basketball Association Finals – the study also found that those who return to play after ACL reconstruction come back as strong as their healthy counterparts.

“Our study showed that not only do players perform as well as unharmed players of equal caliber after ACL reconstruction, but they also do so without having to reduce their driving,” said Blake schultz, MD, a fellow in orthopedic trauma at the University of Texas who was a surgical resident at Stanford at the time of the study.

The research was published on November 5 in the Orthopedic Sports Medicine Journal. Kevin Thomas, an MD-PhD biomedical informatics student at Stanford, shares primary authorship of the study with Schultz. Geoffroy Abrams, MD, associate professor of orthopedic surgery, is the lead author.

“Our study provides players, teams and medical staff with information that people who return to elite level competition after having ACL reconstruction surgery are likely to be able to make a full comeback,” said said Abrams, medical director of Lacob Family Sports Medicine Center, which looks after Stanford varsity athletes. Abrams is also an assistant physician for the San Francisco 49ers team.

Shultz developed the idea for the study – which analyzed player performance and injury data collected over 37 NBA seasons – three years ago, as he helped treat patients with ACL injuries as a resident of Stanford Sports Medicine Clinic. Patients have asked him what to expect when they return to the basketball court.

“They wanted to know if they would be able to be that explosive and move towards the basket as well,” he said. “I didn’t know what to tell them. Now I can say, “You can come back to the same level of play and expect to be just as efficient behind the wheel. “

Three dreaded letters

There is a collective thrill among fans, teammates and coaches when an athlete falls with a suspected ACL tear on the basketball court, whether at the high school, college or pro level. Usually that means surgery and months of rehabilitation. The same goes for football and soccer, as well as other sports that can put a lot of strain on the knee, Abrams said.

“An ACL is always a big concern of athletes,” said Jerod haase, head basketball coach at Stanford, who added that he always worries whenever he sees a player’s knee buckle and a player collapses on the court. “You pretty much know if it’s an ACL, that will be the end of the season.”

The anterior cruciate ligament is a band of tissue that connects the thigh bone to the tibia and is crucial for the stability of the knee. Surgical reconstruction involves removing the damaged ligament and replacing it with a segment of tendon from another part of the knee or from a deceased donor.

You pretty much know if it’s an ACL, that will be the end of the season.

Driving to the basket involves quick pivots to maneuver through opposing players with sudden acceleration and deceleration, which puts a lot of stress on the knee, Abrams said. Shooting a basket from a distance involves more up and down movement, a biomechanics that puts less stress on the ACL.

Still, scientific research has been mixed as to whether there is a clear link between ACL tears and driving to cart, according to the study.

A whole lot of statistics

Using publicly available data collected primarily from online sources, including injury reports and press releases, the researchers identified 97 NBA players who had ACL tears since 1980. They excluded them. athletes who played before 1980 because 3-point shooting was introduced that year, which dramatically changed stats, Thomas said.

Of those 97 players, they reduced the number to 50 for analysis: They excluded players for reasons such as playing in another league after their injury or having suffered a previous ACL tear.

Data on how often players go to the basket has only been kept by the NBA since 2013, but researchers needed this information for the previous three decades of games. To overcome this challenge, they collected 49 more traditional stats related to playstyle, then developed an algorithm to estimate player behavior tendency from those traditional stats.

The results of the study showed that players with high professional driving tendencies suffered ACL tears at a rate of 5.2% compared to those with a lower driving tendency, who suffered tears at rates of 3.8%.