Foot structure and the mechanics of movement are closely linked. The connection between high arches and a specific gait pattern is a common source of confusion for many people experiencing foot discomfort. Understanding this relationship, often discussed using the technical terms Pes Cavus and supination, is important for proper management of foot-related issues.
Defining High Arches and Supination
High arches, medically known as Pes Cavus, describe a foot structure where the medial longitudinal arch is raised higher than what is considered typical. This elevated arch does not flatten or touch the ground even when bearing weight, unlike a normal foot that flexes under load. Pes Cavus can be a benign inherited trait or a sign of an underlying neurological condition.
Supination, also called underpronation, is a movement pattern observed during walking or running. It refers to the foot’s tendency to roll outward, placing the majority of the body’s weight onto the lateral, or outer, edge of the foot. Supination is a normal phase of the gait cycle, helping the foot become rigid for push-off. However, it becomes problematic when this outward roll is excessive or prolonged, compromising the foot’s ability to absorb shock effectively upon impact.
The Biomechanical Connection
The structural rigidity of a high-arched foot often forces a supinated gait pattern. The arch’s height creates a naturally rigid structure, which lacks the flexibility needed for proper shock absorption. A foot with a typical arch is designed to pronate, or roll slightly inward, immediately after the heel strikes the ground. This pronation acts as a natural shock absorber and allows the foot to adapt to uneven surfaces.
A high-arched foot lacks the necessary mobility to perform this crucial inward roll, limiting pronation significantly. Because the foot cannot unlock and flatten to dissipate ground reaction forces, it remains locked in a supinated position throughout the stance phase of the gait cycle. This failure to pronate means the foot is unable to act as a mobile adapter, forcing impact forces to travel directly up the kinetic chain to the ankle, knees, hips, and lower back. The result is chronic weight bearing along the outer edge.
Common Issues Related to Supination
The lack of shock absorption inherent in a rigid, supinated foot structure is the source of several common orthopedic problems. The body’s inability to cushion impact efficiently increases the stress placed on bones and soft tissues. A frequent consequence is the development of shin splints, or medial tibial stress syndrome, as impact forces are transmitted up the lower leg.
Stress fractures, particularly in the metatarsals, tibia, and calcaneus, are linked to this repetitive, unabsorbed impact. A foot that constantly bears weight on its outer edge creates an unstable base, making the ankle more susceptible to recurrent sprains and instability. The excessive strain on the foot’s connective tissue can also lead to pain near the heel, including plantar fasciitis, due to limited flexibility. A visible sign of chronic supination is the excessive and uneven wear on the outer heel and lateral forefoot of shoes.
Addressing Foot Supination
Management for supination caused by high arches focuses on providing cushioning and distributing pressure more evenly, rather than forcing a change in the foot’s structure. Footwear selection is a primary consideration; individuals should look for shoes with high levels of cushioning and a neutral sole. It is advised to avoid “motion control” shoes, as these are engineered to limit pronation and would be counterproductive for a foot that already lacks this movement.
Orthotics, whether custom-made or over-the-counter, should be designed to absorb impact and provide gentle support without aggressively pushing up the arch. The goal of a supination-specific orthotic is to cushion the foot and redistribute pressure away from the outer edge, not to correct the structural arch height. A program of stretching and strengthening can also address the secondary effects of the rigid foot. Stretching tight muscles in the calves and ankles improves flexibility, while strengthening exercises help improve ankle stability and the body’s ability to handle impact.