Theta relates directly with the ability of any device, custom orthotic, arch supporting / foot controlling, shoe modification or insert, constructed from any material, by any means of fitting or fabrication, to change foot and leg function as we walk, stand and run.

Theta is the angle of the wedge measured in degrees.

Protractors and light boxes can measure Theta.

Clinical research with Theta between 1984 and 1990 resulted in the design of a device recorded in the United States Patent office as application number 7,624,550

tan(theta) A-C = A-B

Calipers and trigonometric formulas can measure Theta.

Theta is measured in a frontal plane section taken where the device lines up with the talo-navicular joint (high point of the arch) of the foot. If this section is divided into 4 parts from inside (medial) to outside (lateral), only the center 50 percent of the curve is used to plot the points that define theta. This explains why the high medial flange design, portion of the wedge outside the definition of theta was determined  by most clinicians to be mostly ineffectual.

This angle was not easy to measure because it is taken from a section through the apex of the arch that is shaped like a hyperbolic curve.  The points that define where theta is measured A, B, C, had to be defined above before theta could be related to function. Once theta could be measured we began to learn.

• We learned that every 5 additional degrees of wedge doubles the functional benefits.
• We learned why most physicians firmly believe that prescription orthotics (average 18 degrees of theta) are better than over the counter prefabricated devices (average 11 degrees of theta).
• We learned than no other device in the world had more than 23 degrees of correction and only the  Alzners can consistently give you that much correction.
• We learned that optimal correction is at 40 degrees for most patients and that you have to gradually restore optimal function.

Today we use seven different levels of Theta between 10 and 40 degrees. They are all quantified by hand with calipers.

Many patients get sufficient help with just one of our seven different levels.  With seven levels to choose from there are many more options than any one else provides. Theta easily treats patients with both low an high arches. Others choose to increase at least five degrees or one level. Many do exactly as our research indicates should happen and work their way up to 40 degrees where optimal Theta Control is believed to occur. Most increase until the pain is gone, then stay comfortably at that level.