Tibial Internal Rotation Part 1: Why we need it

by Mitch Hauschildt, MA, ATC, CSCS

For a number of years in my clinical practice, I have largely ignored the triplaner mechanics of the lower leg. Meaning, I didn’t fully appreciate the need for movement in multiple planes of motion in the lower leg, and specifically the Tibia. After all, I was taught that the knee is a hinge joint and the ankle is a mortise joint; both only allowing for movement in a single plane of motion motion

As time moved along during my career, I began to understand that nothing with the human body occurs in a vacuum and for the most part, it isn’t all that consistent from person to person. Thus, there is much more to most joint functions than just one plane of movement. But, it wasn’t until I began using the Selective Functional Movement Assessment (SFMA) in my practice that I began to actually look at Tibial Rotation as something that my athletes need.

After I started assessing it, I quickly found out that many of my athletes are rather deficient in this area. I quickly started addressing it (I’ll get to how in part 2), and what I discovered is that athletes with patellofemoral, medial and lateral knee pain all saw an immediate impact in their symptoms as well as many of my athletes with lower leg and mid pain. So I began to dig into why a lack of Tibial internal rotation can become problematic. To start that conversation, we must understand the kinematics of the knee and ankle joints.

In a “normal” knee, there is between 20 and 30 degrees if tibial internal rotation (femoral external rotation) during flexion m0vements up to 90 degrees. This occurs mostly on the lateral side of the knee with the lateral femoral condyle moving posterior relative to the tibial plateau while the medial femoral condyle remains largely unchanged in its position on the tibia.

What I find interesting is that in at least 2 MRI studies of the knee, researchers found that the knee will flex to 90 degrees, regardless of the amount of Tibial internal or external rotation in weight bearing by simply adjusting how much rotation was needed within the joint itself to complete the task. This infers that tibial rotation can be modified by the body to fit the demands placed on the body at that time and is not necessarily an obligatory process for knee flexion.

So, the amazing accommodating machine that is the human body can find ways to get around this stumbling block. Unfortunately, like most other compensation patterns, over time, such compensations will impact the rest of the body. Over time, any less than optimal movement patterns will result in pain and/or problems somewhere in the kinetic chain.

At the ankle, Tibial internal rotation is important for assisting in pronation during weightbearing to create a shock absorber in the foot and ankle. Without the ability to rotate internally at the lower leg, this ability to pronate (in a healthy manner) is limited.

So, what does it all mean?

Finding research tying specific injuries to lack of Tibial Rotation is a bit difficult. But, what I will tell you is that clinically, it can be connected to multiple knee issues, including patellofemoral pain, lateral and medial knee pain. It can also be linked to Pes Anserine pain and I believe that you can make the argument that someone who is chronically stuck in an externally rotated position in their lower leg may be at a heightened risk for ACL tears.

In the lower leg, I see patients with foot, ankle and shin pain presenting with poor Tibial internal rotation. This can be linked back to their inability to absorb force, as well as poor kinematics around the ankle mortise joint.

As it relates to specific injuries, I always think about the statement that Kyle Kiesel told me during my SFMA certification. He said, “Can I tell you for sure that one specific dysfunction is causing their pain? No. But, I also can’t say for sure that it isn’t causing it, so I better fix the dysfunction when I see it.” That statement resonated with me then and has shaped how I approach movement corrections.

And, while this doesn’t exactly fit into the Joint-by-Joint approach that Cook and Boyle speak about, their concept has application here. Basically, the foundation of the Joint-by-Joint approach is that certain areas of the body are supposed to be stable and some are supposed to be mobile. If you identify an area that is supposed to be mobile (or stable for that matter) and it isn’t, then you better fix it to restore the natural function of the body.

In this case, if you find someone in pain and they don’t have at least 20 degrees of Tibial internal rotation, I can’t say that it is causing their pain, but I can’t say that it isn’t. So, I better fix it. In part 2 of this series, I will present strategies for improving Tibial internal rotation.

References:

Johal, P. et al. “Tibio-femoral movement in the living knee. A study of weight bearing and non-weight bearing knee kinematics using ‘interventional’ MRI” Journal of Biomechanics. 2004

Freeman, M. & Pinskerova, V. “The movement of the normal tibio-femoral joint.” Journal of Biomechanics. 2004