Anthony Pettis' Knee Injury and Rehabilitation

Bloody Elbow 2.0 | Anton Tabuena

On September 3rd Dana White announced via Twitter that UFC lightweight champ Anthony Pettis had suffered a grade II sprain of the posterior cruciate ligament (PCL) in his knee. The injury occurred in his recent championship bout with Benson Henderson at UFC 164. Pettis is expected to be out of action for the next 7 weeks, but will not require surgery for this injury.

Isolated injury to the PCL is not nearly as common compared to the ACL. PCL injuries are usually seen in combination with other ligament injuries, including the lateral collateral ligament (LCL), which was apparently the case with Pettis. The grade of Pettis’ PCL injury (grade II) suggests that there was some tearing of the ligament to the point where it becomes loose, but not a complete tear. Tears of the PCL are not typically corrected with surgery, as the PCL is not as critical to the stability of the knee as is the ACL. (Can you remember the last time a UFC athlete was pulled from a fight with a PCL injury?) Still, rehabilitation of the knee after PCL tear is important to an elite athlete in order to restore full function.

The PCL functions to resist posterior (or backward) translation of the tibia upon the femur. There are obvious functional implications for a fighter with a deficient PCL. For example, consider a fighter executing a takedown, as shown in this gif of Georges St-Pierre.

via ZombieProphet

As GSP’s right knee and lower leg impact the mat, there is a sudden posteriorly-directed force on the knee, which could stress or further injure a PCL-deficient knee.

In the early phase of rehabilitation after a PCL injury, the goals are to limit or reduce knee joint swelling, restore full knee range of motion and regaining strength and control of the quadriceps muscle group. In fact, strengthening of the quadriceps should be a big point of emphasis throughout Anthony’s rehab. The quads, located on the front thigh, are important in resisting the posterior translation movement of the tibia during high demand activities, such as grappling or wrestling. The body’s sense of balance, coordination and proprioception are affected with most knee injuries, and Pettis’ PCL injury is no different. (Proprioception refers to the unconscious perception of movement and spatial orientation, and the joints of the legs play an important role in this.)

As Pettis progresses, closed chain exercises will be very important in his rehabilitation. Closed chain exercises are performed with the foot in contact with the ground, and this type of exercise provides the opportunity to restore the sense of proprioception. These exercises help to create a co-activation of the quadriceps and hamstring muscles of the leg, which in turn can help decrease the back and forth shearing of the tibia on the femur at the knee[1].

I expect that Anthony will make a quick and full recovery from this injury, with no significant effect on his fighting game.

1. Rosenthal, MD, Rainey CE, et al. Evaluation and management of posterior cruciate ligament injuries. Physical Therapy in Sport 13 (2012);196-208.