In the preseason finale, the Baltimore Ravens took on the Washington Football Team. As many coaches and organizations how they choose to navigate the revamped preseason, Baltimore played their starters for a final tune-up. Running back J.K. Dobbins was injured on a screen pass early in the first quarter.
After being taken to the medical tent…
J.K. Dobbins was carted off the field and after the game, Coach Harbaugh addressed the media stating he will undergo further testing on Sunday to determine the severity of the injury. There’s certainly been no shortage of predictions of the knee injury ranging from a sprain all the way to completely torn and from ACL to PCL and every other ligament and structure involved.
Anatomy Review
The structures of interest for J.K. Dobbin’s injury are the anterior cruciate ligament (ACL), the posterior cruciate ligament (PCL), the lateral collateral ligament (LCL), and the medial collateral ligament (MCL). Each of these ligaments, in addition to the joint capsule provide stability to the knee joint. The ACL prevents anterior translation of the tibia about the femur. The PCL prevents posterior translation of the tibia about the femur. The MCL provides medial stability and prevents excessive medial (valgus) movement of the knee. The LCL provides lateral stability and prevents excessive lateral (varus) movement of the knee.
Each of these structures are unique. The ACL is oriented obliquely and a thinner compared to the thicker, shorter, less obliquely oriented PCL. The LCL is a fibrous cord-like ligament while the MCL is a flatter, broader ligament that blends into the medial meniscus.
Any time there is a direct blow to the knee that causes the knee to hyperextended your immediate concerns goes to the ACL and then PCL. It is more common for the ACL to be damaged compared to the PCL because the ACL is thinner and more often the mechanism of injury for the PCL is with a flexed (bent) knee and it moving posterior.
The next structures to evaluate after the ACL and PCL are going to the be the MCL and LCL and then if there is ACL damage, you check the MCL and also the medial meniscus. Given the video and there was hyperextension and some valgus (inward) motion of the knee and potentially some rotation, which could signal MCL and/or medial meniscus involvement.
Since the knee cwas hyperextended another structure involved was the knee capsule, specifically the posterior knee capsule. The knee capsule provides stability of the knee and assists in maintaining the congruency and alignment of the tibia and femur joint complex.
X-ray will be taken to determine if there was any bone involvement. But the MRI is required to determine what soft tissue structures (muscles, ligaments, tendons) are involved and the severity of the damage.
Designated To Return
Until imaging has been taken to determine the structures involved and the severity of the damage, J.K. Dobbins could miss several weeks up to the entire season. This reminds me of Giannis Antetokounmpo hyperextended left knee he suffered in the NBA Playoffs and everyone thought he completely tore his ACL and was going to miss an entire year. I don’t believe it has ever been reported what his official knee injury was other than “hyperextended” left knee. But until imaging everything is just speculation to determine how much time he is going to miss.