Top 100 Biomechanical Guideline #63: Extrinsic Rear Foot Posts can be Modified in Many Ways

The attachments in the heel area of functional orthotic devices are called posts (extrinsic rear foot posts to be exact). They help stabilize the foot and can play a minor or major role in the orthotic device. They can also be modified many ways to limit motion, create motion, change positioning of the body (called canting), and be accessorized (here with a heel lift for short leg syndrome). 

This is the normal way I look at an extrinsic rear foot post, from the back. The post holds the correction prescribed in the orthotic device. It also acts like a heel lift to gentle push the body weight forward. Most arch supports hold the body weight too far back, so the post can help can your body weight forward.

When you deal with the biomechanics of a patient, you are always trying to correlate injury to function. When you have major complexities working together, things can get exciting in the biomechanics and orthotic world. For example, when trying to treat a patient with shock absorption issues, with a short leg, with excessive pronation, yet overly supinates with any arch support, and has a scoliosis with pelvic asymmetry, changes in post positioning, or post motion can make or break your treatment.