Your Ankle Bones Affect the Alignment of Your Feet

Adapted fromYour Body, Your Yoga
By Bernie Clark
April 18, 2024

You probably never think about your ankles, but take a moment to observe them. Place one finger on the outer bump—this is your lateral malleolus. Now place another finger on the inner bump—your medial malleolus. Notice that the two fingers are not at the same height; your lateral malleolus is likely lower than the medial malleolus. Moreover, the lateral one is slightly behind the inner one. Technically, your lateral malleolus is inferior and posterior relative to the medial malleolus, and this simple fact greatly affects where your feet point when you flex and extend your foot!

Notice the position of the feet in the image above. See how both feet point inward, adducted towards each other. This inward orientation of the feet can occur in many yoga postures where the ankle is plantarflexed—when the toes point away from the knees, as in the back leg of a Pigeon pose or an Upward Facing Dog. Some yoga teachers might correct this foot position, suggesting the student straighten the foot backwards, citing “sickling” that could potentially cause problems over time. However, these teachers would be mistaken. For this woman, the inward pointing is the neutral, natural position for her feet, not a sign of pathology, poor posture, or inattention. It is likely a sign of her having a significant empiric axis.

The ankle joint consists of three bones: the long, slender fibula on the outside of the lower leg; the thicker tibia down the middle of the leg; and the talus at the top of the foot. The average angle of backward tilt from the tibia to the fibula is 20–30°, while the downward tilt is about 10° ¹

Figure 2: (a) The ankle is the junction of the fibula, tibia and talus. (b) The empiric axis runs from the outer distal fibula (lateral malleolus) to the inner distal tibia (medial malleolus). (c) A frontal view of the empiric axis.

Notice that the angle of the empirical axis is not in the frontal plane of the body, meaning that dorsiflexion and plantarflexion of the ankle are not simple planar movements in the side (sagittal) plane. The average angle of the empirical axis in the frontal (coronal) plane is about 10° below the horizontal. For most people, this means that plantarflexing and dorsiflexing the foot will alter the direction the foot points.

Figure 3: The tilt of the ankle. The average empirical axis of the ankle forms a 10° angle to the horizontal plane. However, that is just an average. The standard deviation is 4°, thus the range of variation below the horizontal for this angle for 95% of the population is from 2° (b) to 18° (c). ²

Where do Your Feet Point in Plantarflexion?

As shown in Figure 4c, the empirical axis influences the direction of the foot during plantarflexion. A greater empirical axis angle causes the big toe to adduct more medially. Consequently, when the ankle plantarflexes, the foot will naturally point inward for most people. When you plantarflex your feet in poses like Virasana, Pigeon, or Upward Facing Dog and they point inward, there’s no need to counteract this by internally rotating your femurs in your hip sockets. Your feet are simply following their natural path.

Figure 4: As the ankle flexes, the foot exhibits medial or lateral movement (right foot); in neutral (a), with dorsiflexion (b), the foot abducts superiorly; with plantarflexion (c), the foot adducts medially.

Where do Your Feet Point in Dorsiflexion?

Conversely, during dorsiflexion—pulling the toes towards the shins as shown in figure 4b—the foot naturally points outward. This is evident in a deep squat, where most people’s toes point outward to facilitate hip flexion and balance. This outward pointing is also due to the degree of dorsiflexion required in poses like a low lunge or Downward Facing Dog.

Figure 5: Consider allowing your feet to point inward during plantarflexion and observe the sensation.

What is the Optimal Foot Position?

Where should the foot point? That depends! It depends upon the shape and orientation of your acetabula, the torsion of your femurs and tibias, whether the knee is full extended or deeply flexed, upon the length of your fibula relative to your tibia and the amount of curvature in your talus, and upon how much you are flexing your ankles. There is no predefined “right” position for your feet—but there is an alignment that may be optimal for you, given your anatomical uniqueness. Your challenge is to find what works for you. To do that, you need to learn how to pay attention and observe what is going on when you are in certain postures and positions.

Bottom line: it is probably okay to let your feet point inward during plantarflexion and outward during dorsiflexion. How much is probably related to your unique empiric axis.

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Footnotes:

¹ See C. Kisner and L.A. Colby, Therapeutic Exercise: Foundations and Techniques, 6th ed. (Philadelphia, PA: F.A. Davis, 2012), 851.

² See V.T. Inman, The Joint of the Ankle (Baltimore: Williams & Wilkins, 1976), 19, 26, 27, 31, 37, 70–3.