Joe Burrow

        During week 11 of the 2021 NFL season against the Washington Football Team, Cincinnati Bengals rookie quarterback Joe Burrow dropped back to throw. During the play, defensive tackle Jonathan Allen beat his man and fell into Burrow’s knee as he released the ball. After being carted off, it was clear he had suffered a serious injury. A few hours later, Adam Schefter reported that Burrow had suffered a contact ACL injury. He tore his anterior cruciate ligament (ACL), medial collateral ligament (MCL), and partially tore his posterior cruciate ligament (PCL) and meniscus. Contact ACL injuries occur when something comes into contact with the lower leg resulting in an ACL injury. These injuries can be devastating to NFL players, forcing them to go through a long recovery, and possibly hamper them when they return to play. Between 21-37% of players who suffer ACL injuries never appear in another NFL game. We can learn more about Burrow’s injury by looking at the anatomy of the knee.

To fully understand what happened to Burrow, it is important to know more about the ACL. Stretching from the back of the femur (thigh) to the front of the tibia (lower leg), it resists hyperextension and rotation of the knee. The MCL is another ligament in the knee. It connects from the bottom of the thigh bone to the top of the shin bone while resisting the knee collapsing too far inwards. 

Outside

Inside

The body puts more load on different structures based on how it is positioned. Certain postures can cause more load to be applied to the ACL, influencing injury risk. One such position is when the leg is fully extended and the knee is locked. Any contact with the knee will increase the load on it, possibly resulting in an injury. Forces on the knee are strongest when the knee is fully extended, and there is greater knee abduction movement. This happens when the knee bends too far inwards. Valgus collapse is a combination of the movements above and is one of the predominant recognized mechanisms when diagnosing ACL injuries. Video analysis supports valgus collapse with external tibial rotations, the direction the shin is facing. Tibial rotations also correspond with foot, knee, and hip position. When tibial rotation is greater, the foot is more abducted and the hip is extended more.  It is important to note that ACL tears only happen when the stress on the ligaments exceeds what they can bear, not necessarily a certain set of positions. Contact ACL injuries are often associated with MCL and meniscus injuries. As the knee collapses from contact, the pressure on the ACL is shared by the MCL and menisci. This was the case in Joe Burrow’s injury, as he also suffered a torn MCL and additional structural damage.

Burrow steps into a throw under pressure and gets injured

When Joe Burrow got injured, he was stepping up in the pocket to make a throw when a defender fell into his knee with the additional weight of Burrow’s teammate. Upon contact, Burrow’s knee bends backwards and he goes down in serious pain. He had just released the ball, so he was in a standard throwing position. His foot was firmly planted in the ground, all his weight was on his one locked leg, and his knee was fully extended. When he is hit, his knee is in the worst position possible, being almost fully extended. As he steps into his throw, we can see he has external tibial rotation with his foot being abducted and him having high flexion in his hip. As soon as two 250+ lb players crash directly into his knee, Burrow’s knee buckles and his ACL and MCL tear. 

This ACL injury can have long term effects for Joe Burrow. Looking at the risk of reinjuring his knee, athletes who suffer ACL tears are 15-25 times more likely to suffer another ACL injury to the same or different knee. Athletes also tend to favor their uninjured knee up to two years post operatively. However, quarterbacks are not at as much of a risk. A study analyzed 69 out of the 156 ACL injuries in the NFL during 2013-2016 and found that about 7% of tears belonged to quarterbacks, with 80% being non contact injuries. Athletes between 23 and 28 with ACL/MCL tears have a 70.9% return to play rate. As a 24 year old male, Burrow falls in this demographic and reasonably aims to return next season. He has also stated that he is aiming for a comeback before this upcoming season. The normal timeline for recovering from an ACL injury for NFL players is from 250-350 days after injury. But Burrow also tore his MCL and PCL. The average return to play for players with ACL and PCL injuries is from 200-700 days. While this is a very broad range, Burrow didn’t suffer a complete PCL tear, so his recovery won’t take more than a year. 

Although he will wear a brace for at least the near future, his play on the field shouldn’t be impacted by his injury. Burrow is more of a pocket passer, and doesn’t have to put too much stress on his knee by running. Burrow’s doctor compared his injury to that of former Bengals quarterback Carson Palmer. Palmer suffered a contact ACL injury during the 2005-2006 playoffs, tearing his ACL, MCL, and meniscus. The following season, his completion percentage dropped from 67.8 to 62.3, and his touchdowns fell by four and interceptions rose by one. While he experienced a down year after his injury, Palmer was a reliable quarterback for the rest of his career. He retired with over 46,000 passing yards and almost 300 touchdowns. When Joe Burrow was hit, he wasn’t aware of the defender falling into his knee due to him looking downfield. He was very unlucky and found himself in the worst possible spot he could be in. He couldn’t minimize the impact by going down immediately after contact. In the future, it isn’t only up to Burrow to prevent another injury. The Bengals have prioritized investing in their offensive line this offseason. They signed tackle Riley Reiff in free agency and drafted Clemson guard Jackson Carman in the second round in April. They also drafted Ja’Marr Chase, Burrow’s top wideout in college at LSU. Joe Burrow has a bright future ahead of him in the NFL, but his contact ACL injury will always be a part of his career.

Bibliography

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