As long as your feet and legs are properly aligned, these sequence of motions will occur smoothly and on time with no strains or inefficient motions, pain or injuries. However, inefficient functioning of your feet and/or legs can cause many different problems.

This is because your feet actually function like the front of your car. When the car is out of alignment the tires wear out quicker, uneven stress is placed on the frame. In addition, the steering wheel begins to shake, soon the car functions badly, the tires wear down further and eventually you cannot drive it.

When body weight is thrust on the foot at a time when it is unstable, the bones are subjected to abnormal stresses, which can lead to stress fractures, bone spur formations, enlargement of bones called exostoses, joint injuries, bursitis and arthritis. It also leads to the formation of bunions, hammertoes, heel spurs, painful corns and callouses, etc. In addition, neuromas, or nerve tumors, and other soft tissue tumors of the foot can occur because of it.

Muscles which are designed for stabilization are called upon to help propel, and propeller muscles are forced to help with the stabilization. When the various muscle groups of the lower extremities are called upon to do work that they were not intended to do, they become strained. This is the cause of chronic foot and lower leg pain and muscular fatigue. It can even lead to overall physical exhaustion. And, with the muscles forced to do the wrong work, as described above, stresses are created which can lead to muscle and tendon injuries. In many cases, excessive stresses are transmitted through the legs to the skeletal structure above, producing many of the knee, hip, lower back, shoulder and neck symptoms many of us have and this is especially evident in athletic and fitness injuries to the skeletal system from the hip down.

Inefficient functioning of the feet and legs are usually inherited and leads to excessive rolling inward and downward of the inside of the ankle, sometimes the arch and the front of the foot. This is called overpronation.

Excessive pronation can be controlled. The goal is to hold the feet in a proper position to allow for the feet and legs to function normally and with maximum efficiency. This can be effectively done by the use of prescription orthotics. Orthotics are medical appliances that are contoured to fit each individual foot and may have rearfoot (back of the foot) and forefoot (front of the foot) corrections (post/shims) which represent specific degrees of biomechanical correction in order to retain a proper relationship between the forefoot (front of the foot), rearfoot (back of the foot), leg, and the supporting surface.
The use of orthotics often relieves the various painful aches and pains associated with pronation. They can also prevent future problems from occurring and eliminate the need for more radical forms of treatment, such as surgery.

Orthotics are often used as part of the treatment for various sports injuries associated with fitness activities such as: running, aerobics, walking, racquet sports and cross training, etc. They are similarly used for popular team sports like basketball, soccer, baseball, football, ice skating and hockey, etc. They are also useful in helping prevent athletic injuries and enhance athletic performance levels.

There are various types of orthotics that are made out of different materials and in different shapes. Thus, there are orthotics that can fit and be used in ladies dress shoes and others that can accommodate the various casual and athletic shoes that we use in our daily lives.

The choice of orthotic used i.e, its design, materials, and amount of correction as prescribed by the doctor, depends upon your foot type, the daily activities that they will be used for, the shoes they will be functioning in and several other variables. The type of orthosis utilized is thus customized to an individual patients' needs.