Because you have a curve in your leg bone (Tibial Varum / Bowed Legs).
Humans really do need orthotics. After more than 30 years of studying this problem, this curvature in the lower leg appears to be present in most everyone. It is a frontal plane curve in the tibia. It can be less obvious in many individuals, but it is structurally present and measurable in all humans.
When the knee is in it’s functional plane, the foot is NOT down flat on the ground.
This angular deviation places the contact surface of the foot (transverse plane) unsupported, up in the air, on the inside (medial). As human gait becomes weight bearing the supportive surface of the foot must get down to the horizontal plane of support to hold us upright during human gait.
Naturally as we walk and stand, our body compensates in the best way possible, for this angular anomaly.
The foot can compensate for this angular deformity in the tibia in two primary ways,pronation and supination, and many unique genetic combinations of these two different movements as well. More photos of Tibial Varum
Some individuals supinate.
In a young strong individuals with a healthy neuro-muscular system, the Peroneous Longus Muscle, pulls the first ray down. As the first metatarsal is plantar flexed both the ankle and Sub-Taylor joint are supinated. This brings the supportive surface of the foot down to the ground. When this happens the foot can propel off of the ground during gait and we can physically walk and run.
Some individuals pronate.
Pronation: When the mechanics of the arch are not optimal the first ray can not be plantar-flexed and the foot can not be supinated. Instead of three well defined arches, the gravity provides a vertical force during weight bearing gait that allows the arch to unlock and the forefoot to evert. Pronation of the Sub-Taylor joint in the rear foot, brings the supportive surface of the foot down to the ground. Weight bearing gait is now physically possible.
Unfortunately even patients who can compensate with foot and ankle supination when they are young, gradually pronate more with age. The pronation that occurs in most everyone to some degree creates retro- bio-mechanical forces that create pain with every step , and the upright gait we humans love.
Orthotics use frontal plane wedges to bring the supportive surface of the ground up to the foot to compensate for this curvature in the Tibia. This condition is know medially as Tibial Varum. When the condition is clinically obvious , it is commonly recognized and referred to as Bow Legs. Optimal treatment compensates for this angular anomaly through out the entire weight bearing gait cycle.
Humans need a varus wedge to bring the ground up to the foot during gait.
Fortunately, neither excessive plantar flexion of the first ray, or pronation of the Sub-Taylor joint, are required to propel normally, when a varus wedge compensates fully for the frontal plane curvature in the human tibia. Partial compensation provides functional benefits proportional to the angle of compensation (Theta). THOUSANDS of support devises are available that provide some of the angular wedge that is necessary.
When compensation for the curvature in the tibia is achieved, gait is changed, and chronic pain subsides.
- Only Theta Orthotics provides above 22 degrees or rear-foot angular correction,
- Only Theta Orthotics provides up to 37 degrees of rear-foot angular correction.
- Only Theta Orthotics provides up to 19 degrees of forefoot angular correction.
- Only Theta Orthtoics provides bot fore foot and rear foot angular correction.
ONLY Theta Orthotics can fully compensate for this angular deformity with up to 19 degrees of forefoot and 37 degrees of rear-foot wedges.
EVERY 5 DEGREES of wedge, up to 37 degrees, will DOUBLE THE functional BENEFITS of an ORTHOTIC. Progressive treatment programs that result in correction levels between 27 and 37 degrees can achieve clinical results not observed with other treatment modalities including other orthotic devices. Humans need orthotics to compensate for the naturally occurring Tibial Varum in their lower legs.