The Ankle And How It Is Related To Function

April 20th, 2020

The ankle is a complex joint that allows for movement in various planes:
dorsiflexion/plantarflexion (up and down), inversion/eversion (in and out), and
pronation/supination (arch down and arch up). While having adequate mobility in each direction is important, dorsiflexion, or the ability for the foot/ankle to move upward towards the ceiling, has the most functional implications. When we squat to pick an object off the floor, walk, run, descend stairs, drive, or even just lower oneself onto a chair, there is a degree of dorsiflexion required to perform these actions. Being deficient in dorsiflexion could lead to compensatory strategies while performing these movements, which may predispose people to injury. This article will focus primarily on dorsiflexion and its role in function, including at home assessment and corrective exercises to address and restore dorsiflexion limitations.

Dorsiflexion Requirements for Functional Tasks:

  • Walking: 10-20 degrees (1)
  •  Running: 30 degrees (1)
  • Squatting: 40 degrees (2)
  • Landing mechanics: If there is a deficiency in dorsiflexion, there will be an increase in knee valgus moment with subsequent decreased knee flexion that can be associated with ACL injuries (3)

Assessing Dorsiflexion:

When assessing ankle dorsiflexion mobility, an individual has both weight-bearing and non weight-bearing options. It is important to note that most functional tasks are performed in a weight-bearing position, therefore one should utilize a weight-bearing assessment tool.

  •    ½ kneeling lunge assessment (minimal weight-bearing) vs standing lunge assessment (weight-bearing)- both assessment techniques will be beneficial as it will gain some insight on the amount of closed chain dorsiflexion an individual may possess. When performing these tests, it is important to maintain a neutral hip/knee/ankle alignment as well as maintain heel contact to the floor. For the ½ kneeling lunge, place your front foot about 4 inches away from the wall. The goal is for your knee to touch the wall before your heel comes off the floor. For the standing lunge test, the goal is to get the back knee past the front ankle before the heel comes up. See the video below for a demonstration.

  • Squat Assessment:

When performing this test, it is important to maintain knee to knee and heel to floor contact while keeping an upright torso. If adequate ankle mobility is present, an individual will be able to squat down past 90 degrees while maintaining the previously mentioned criteria. Limited dorsiflexion may cause an individual to lose balance, lean forward excessively, or experience an increase in sensation or  pressure to the front or back of the ankle. 

  • Step Down Assessment:

During this assessment, there is also a stability component involved since it requires an individual to stabilize/balance while performing this task. Using an 8 inch box, an individual should be able to lower their opposite heel to the ground without the heel on the step/box from rising. Noting the picture below, you can see how much dorsiflexion is required to properly step down from a step.

Corrective Exercises for Restoring Dorsiflexion: 

It is important to determine if the lack of mobility is due to soft tissue (calf) or ankle joint restrictions. An easy way to assess this is by determining where the sensation or stretch is felt during the tests mentioned above. If you feel more of a stretch in the back of the ankle/heel, then it is most likely a soft tissue limitation restricting dorsiflexion. You will need to perform soft tissue work to both the gastroc and soleus muscles. However, if the sensation or pressure is felt in the front of the ankle, it is most likely an ankle joint restriction causing a lack of dorsiflexion (3).

  •  ½ kneeling lunge mobilizations with band (ankle joint restriction)-
    similar set up to the assessment but now a
    band will be pulling the shin bone back which will create more space in the ankle joint to dorsiflex.

  •   Gastroc (left) and soleus (right) stretching (soft tissue restriction)
  • Soleus foam or pin rolling (soft tissue restriction) –
    to
    access the soleus, the knee will have to be bent. Taking a pin roller, search for sensitive areas in the back of the lower leg to focus your attention on.

    Conclusion:

    The purpose of this post is to share the importance of the role of ankle dorsiflexion mobility in performing functional tasks. While many joints are involved in daily tasks such as squatting and running, it is important that ankle joint mobility, specifically dorsiflexion, is assessed in order to maximize function and reduce the risk for injury. If you are having trouble with one of the assessment techniques or corrective exercises, contact your local physical therapist. 

     

    1. Novacheck, TK. The biomechanics of running. Gait Posture, 7(1): 77-95. 1998. 
    2. Hemmerich, A, Brown, H, Smith, S, Marthandam, S S and Wyss, U.P. Hip, knee, and ankle kinematics of high range of motion activities of daily living. Journal of Orthopaedic Research, 24(4): 770-781. 2006 
    3. Howe, L. Restricted ankle dorsiflexion: methods to assess and improve joint function. Professional Strength & Conditioning, 37:7-15. 2015