The foot is designed to absorb impact and adapt to various surfaces encountered during daily activities. This adaptability involves natural motions like supination and pronation, which are opposite yet complementary movements in the foot’s mechanics. This article explores supination, its nature, and how to recognize it.
What is Supination?
Supination describes a foot motion where it rolls outward, shifting weight primarily onto its outer edge. This typically results in a higher arch. During the gait cycle, supination is a natural part of propulsion, allowing the foot to become a rigid lever for pushing off the ground.
Supination is a triplanar motion. These components include inversion, where the sole of the foot turns inward. Another component is adduction, which involves the foot turning inward towards the body’s midline. Lastly, plantarflexion occurs, causing the toes to point downwards. While a degree of supination is normal and necessary for foot function, it can become problematic when it is excessive or prolonged, leading to an inability to properly absorb shock.
Identifying Supinated Feet
Recognizing supinated feet involves observing visual cues and examining footwear. Individuals with supination typically exhibit a visibly high arch, and their feet may appear to roll outwardly when standing or walking. The toes might also point slightly inward.
Inspect wear patterns on old shoes for identification. Shoes of someone with supination will show excessive wear along the outer edges of the sole, particularly at the heel and forefoot. Placing a well-worn shoe on a flat surface can also reveal if it noticeably tilts outward. Another simple assessment is the “wet test,” where one wets their bare feet and steps onto a surface like paper or cardboard. A supinated foot will leave a footprint showing very little or no contact from the arch, with only the heel and ball of the foot prominently visible.
Common Issues Associated with Supination
Persistent or excessive supination can lead to musculoskeletal problems due to altered biomechanics and reduced shock absorption. The foot’s inability to adequately cushion impact places increased stress on joints and tissues throughout the leg and even higher up the kinetic chain.
Common problems include an increased risk of ankle sprains, as the foot’s outward roll makes the ankle less stable and more susceptible to rolling. Plantar fasciitis, characterized by pain in the heel and arch, can develop due to increased strain on the plantar fascia ligament. Other issues include shin splints, which are pains along the shin bone, and metatarsalgia, causing pain in the ball of the foot. Excessive supination can also contribute to iliotibial (IT) band syndrome, a condition causing pain on the outside of the knee, and even lead to discomfort in the hips and lower back.