Patient Presentation | High Tone Pronation / Supination

Working with practitioners, designing and manufacturing DAFO braces and caring for patients for over 25 years has provided Cascade experience to develop a patent-pending approach to patient groupings and brace selection. This approach is to assess each patient’s presentation from the bottom up. We look first at the biomechanical needs of the foot, followed by the ankle and finally the knee. Based on what is most often seen in our patient population, Cascade has developed seven primary patient groupings. These groupings are organized by whether the presentation, if ambulatory, is foot related, ankle related or knee related. One of the patient groupings is for those who have limited or no ambulation. This issue features the High Tone Pronation / Supination patient presentation group.

High Tone Pronation / Supination

For patients presenting with high tone, the high tone muscle contractures can pull the foot into either a pronated or supinated alignment. Pronation = valgus heel; collapsed arch; forefoot abduction; whereas supination = varus heel; high arch; forefoot adduction. The muscle rigidity, or tightness, driving these presentations is caused by erroneous muscle-activation signals, which are generated by problem areas in the brain or the neuro-pathways that deliver signals from the brain.

Patients in this group can have mild to severe foot alignment problems, with ankle range that remains reasonably good. As the severity of foot misalignment increases, it is likely that ankle function will be limited by poor foot position, but corrections to foot alignment may return the ankle to full function.

Unlike flexible low tone feet, high tone feet are often difficult to correct to a balanced (not pronated; not supinated) alignment. Feet that appear to require very little correction may require surprising force to make the correction. In moderate to severe cases, the force required to fully correct the foot can be very high, often beyond what a DAFO brace can comfortably control.

The general strategy is to correct each foot to the best available position that requires “modest” hand pressure to maintain. If you have to apply a lot of force with your hands to fully correct the foot (hindfoot vertical, forefoot horizontal), then it is better to back off from “full” correction until a slightly less improved alignment is more easily maintained. We recommend keeping the hindfoot in a vertical alignment whenever possible. This is best for transferring the patient’s weight directly through the bones to the ground. Even a slightly everted or inverted heel leaves the foot vulnerable to a rotational load on the ankle and heel. Allowing a little varus in the forefoot of the pronated foot, or a little valgus in the forefoot of a supinated foot, will lessen the overall corrective force, while maintaining the hindfoot in a more vertical alignment (see the Cascade Dafo website for more information on Forefoot Posting).

For moderate to strong low tone pronation, both in early intervention and for older patients, the new JumpStart brace design with two molded nesting plastic shells, provides comfortable, wrap around control of foot position and support and stabilization to the heel. The JumpStart is also indicated for early intervention of mild high tone pronation/supination. For the mild to moderate high tone pronator or supinator, foot correction requires the full wrap-around control of a DAFO style brace to overcome even relatively mild high tone. For the milder cases, the DAFO 4 will usually provide sufficient control. If the pronator’s hindfoot eversion (valgus heel), or the supinator’s hindfoot inversion (varus heel) is moderate to severe, the leverage applied by the DAFO 3.5’s flexible proximal component will provide the additional medial-lateral stability needed to gain control of the heel rotation. Other brace styles with proximal components (DAFO 2 or Turbo) would also work, provided the applied ankle control was suitable, or an acceptable compromise.

Bracing the high tone foot, particularly when the foot is not fully correctable, is always a challenge. Accurately capturing the shape of the foot in casting – especially the bony prominences – is a critical first step. For the pronator, the navicular on the medial side of the foot will be the area prone to irritation; for the supinator, the base of the fifth metatarsal on the lateral side becomes an area of concern. In these cases, adding additional supportive features to the brace is encouraged. These optimizing features (external stabilization, ST support, spot padding, forefoot posting, etc.) can significantly enhance brace comfort and function (see the Cascade Dafo website for more information on Optimizing).

If you have patients presenting with high tone pronation or supination, and would like to better understand the available DAFO bracing support options, our Technical Support staff is on hand to help guide you through the choices.

To learn more about all seven patient groups, visit our website www.cascadedafo.com, There you will find a variety of resources, including: an archive of newsletter articles covering different patient groups, a downloadable pdf Product Selection Guide Handout covering all seven groups, a poster version of the Product Selection Guide that you can order for free and an interactive web-based version of the poster, which relates the patient groups to possible DAFO and bracing options for support.