Could stiff ankles be contributing to your knee pain?
Knee pain caused by high impact activities such as jumping and running may be caused by stiffness in the ankles! This is because stiffness and poor movement range of the ankles (particularly bending the ankle, properly called “dorsiflexion”) prevents the ankle from moving in an optimal way and causes the knee to take on extra stress.
How do I know if I have stiff ankles?
The knee-to-wall test is the most simple test to use to assess your ankle dorsiflexion range.
To do this test, stand in a slight lunge position, with your lead foot’s big toe touching a wall. Your lead foot’s ankle is the joint you are testing. Make sure your hips, knees, and feet are facing forwards and square with the wall. Then lunge forwards (bending your lead knee and ankle) until your lead knee touches the wall – do not let your lead foot’s heel come off the ground. If it touches, stand up, take your lead foot’s big toe 1cm away from the wall and try the lunge again without the heel coming off the ground. Repeat this process until you’re at a distance where your lead knee cannot touch the wall without your heel coming off the ground. The distance in centimetres between your big toe and the wall is your knee-to-wall score. Tip: you can use your hands for support against the wall if needed, and your rear foot’s heel is allowed to come off the ground. Compare your left & right ankles and see if there is a difference in the knee-to-wall test. The larger the distance in centimetres, the more dorsiflexion or mobility you have in that ankle.
What do I do if I have stiff ankles?
Stretching the calf muscle may be your first port-of-call. Standing on the ball of your foot on a step with your heel hanging off the edge is a good start. Try this for a minute a day on each leg, and aim for a minimum for 5 minutes of total stretching time per week^1. Alternate this with the same stretching position but with your knee bent – this stretches a different portion of your calf muscle. For a more in-depth look into stretching, read our article from our Southport Clinic, Ferry Rd Physio, HERE.
Another option is foam rolling. A 2022 study by Seever, Mason, and Zech found that rolling the calf for 3 minutes 6 days a week, for two weeks generated improvements in ankle dorsiflexion range that persisted for at least a week after stopping foam rolling. Another study by Chang et al in 2021 supported this, demonstrating that a single 3 minute foam rolling session was sufficient to improve ankle dorsiflexion.
Lastly, a lunging calf stretch with a joint glide can also improve ankle dorsiflexion range. Loop an exercise band (a belt with a towel to protect the skin can work in a pinch) around the top of your foot and apply tension pulling backwards. After this tension is applied, lunge forwards as far as possible and maintain the tension in the band. Hold for 3 seconds, relax the lunge and undo the tension. Repeat this up to 10 times. This technique is technically called an “Ankle dorsiflexion MWM” or “mobilisation with movement”.
Why (in more detail) can stiff ankles be a source of knee pain in jumping and running?
When you are landing after a jump, or a large stride during running, your body needs to absorb the force somehow. As you land, your three primary lower limb joints all flex (bend) in sync, compressing like a spring under the weight of your body and gravity. As these three joints flex, the muscles controlling the joints tense to take on the force. If your ankle, knees, and hips didn’t flex at all, the majority of the force of landing would go straight through the cartilage and bone of your joints.
For a given amount of force in landing, all three joints have an optimal amount of flex or “give”. Beyond this optimal amount, the muscles don’t work as well to absorb the landing force, and the joints move into positions which are uncomfortable and possibly harmful. If your ankle is particularly stiff and does not achieve its optimal “give” during landing, then this forces the other two joints to compensate and make up the difference – the knee is often the first to take on extra load. This can mean your knee bends further than might be safe, or twists outwards or inwards, whatever it can do to absorb the landing force which isn’t taken on by the ankle. Over time, this can lead to pain and other symptoms in the knee as it is not being used optimally.
Knee pain and ankle stiffness – References
1. Chang, T. T., Li, Z., Zhu, Y. C., Wang, X. Q., & Zhang, Z. J. (2021). Effects of Self-Myofascial Release Using a Foam Roller on the Stiffness of the Gastrocnemius-Achilles Tendon Complex and Ankle Dorsiflexion Range of Motion. Frontiers in physiology, 12, 718827. https://doi.org/10.3389/fphys.2021.718827
2. Seever, T. C., Mason, J., & Zech, A. (2022). Chronic and Residual Effects of a Two-Week Foam Rolling Intervention on Ankle Flexibility and Dynamic Balance. Frontiers in sports and active living, 4, 799985. https://doi.org/10.3389/fspor.2022.799985
3. Taylor, J. B., Wright, E. S., Waxman, J. P., Schmitz, R. J., Groves, J. D., & Shultz, S. J. (2022). Ankle Dorsiflexion Affects Hip and Knee Biomechanics During Landing. Sports health, 14(3), 328–335. https://doi.org/10.1177/19417381211019683
4. Thomas, E., Bianco, A., Paoli, A., & Palma, A. (2018). The Relation Between Stretching Typology and Stretching Duration: The Effects on Range of Motion. International journal of sports medicine, 39(4), 243–254. https://doi.org/10.1055/s-0044-101146