November 2003

How to give an orthotic screen test

by Dr. Mark Charrette

Most busy chiropractors don't have the time, equipment, or office space required to perform a comprehensive gait analysis on every patient. The solution is to perform a simple, brief screening evaluation that still provides considerable treatment planning information. This lower extremity screen will raise 'red flags' to identify patients who need more in‑depth evaluation. These five steps are easy to add to your examination procedures, and offer a good objective test which can determine arch collapse.

Five easy steps

1. Watch every patient walk. By observing a few normal paces, several abnormal gait findings can be distinguished. The most common fault is foot flare, or excessive toeing‑out during walking. Look at the alignment of the foot with the lower leg as your patient walks. An angle greater than 10? to 15? is a red flag for excessive rotational torque stresses into the knees, sacroiliac joints, and spine. Also, look for rarer problems like toeing‑in, limping, lurching, and also foot drop (which may indicate a major neurological problem).

2. Observe the shoes. Check for any excessive or abnormal wear patterns present, especially on the heels. Any asymmetrical, excessive, or lateral (rather than posterior) heel wear constitutes a red flag. This is good evidence of poor pelvic and spinal support by the lower extremity, with abnormal biomechanical forces.

3. Foot/knee alignment. If knee joints are not in line with the feet, pelvic adjustments will not hold as well as you might expect. Look at the lower legs from the front. Mentally drop a straight line down from the mid‑point of each kneecap to the foot. If this imaginary plumb line does not strike the foot over the first two metatarsals, that's a red flag.

4. Is the Achilles tendon straight? When you see a patient's heel cord bowing inward (medially), you have a red flag that indicates probable calcaneal instability. When the heel bone is not aligned with the Achilles tendon, the patient frequently is an overpronator. This biomechanical fault is often an important part of the patient's back symptoms.

5. Check the medial arches. A quick palpation of the medial arches of the patient's feet while he or she is standing will speak volumes about biomechanical efficiency. If you cannot get your finger under the medial longitudinal arch, you have a red flag. If you can push a finger under the arch, take a moment to push upwards into the plantar fascia. With just a brief palpation you will be able to tell if the connective tissue that supports the arch is intact, or is under excessive strain. If pushing up into the bottom of the foot causes pain, it is very likely that your patient has plantar fascitis ‑‑ hopefully still at a stage where conservative biomechanical treatment will be rapidly helpful.

Navicular drop test

When you have detected several red flags, or the presence of foot and ankle symptoms, the next step is to perform the navicular drop test which measures foot support. This procedure takes very little time, and requires no additional space or expensive testing equipment.

All you need are a marking pen and a piece of 3"x5" card stock. With the patient sitting comfortably (feet on the floor, but non‑weightbearing), palpate the medial aspect of each foot and find the navicular prominence (the most prominent bony landmark found inferior and somewhat anterior to the medial malleolus). Using the pen, make a mark on the patient's skin at the point of the navicular prominence. Stand the card on the floor next to the medial arch of the foot and mark the card at the level of the navicular prominence.

Next, ask the patient to stand, in a relaxed position. Once the arch is weightbearing, the navicular prominence will be somewhat lower. Make a second mark on the same side of the card at the new level of the navicular prominence. Repeat this procedure with the other foot. Now measure the difference between the two marks for each foot. If there is a drop of 4 mm. or more in the arch between sitting and standing, or if there is an obvious asymmetry from left to right, this is objective evidence of a functional foot problem ‑‑ hyperpronation/collapse of the medial arch. This condition is best treated with custom‑made, flexible orthotics designed to be worn during all weightbearing activities.

A major custom‑made orthotics company has created a 'Postural Stability Indicator' card, based on the procedures of the navicular drop test. With this specially designed card, you can have a permanent record of the results of the objective testing of your patient. Patients are impressed by this professional approach and the measurable and well‑documented findings.

Results

With the screening and measurement procedures described above, you can perform a functional and useful gait evaluation quickly and efficiently. No fancy equipment is necessary, and the small amount of time required is rewarded when you identify a potentially difficult case that will now respond rapidly to chiropractic care and orthotic support.

(Dr. Mark N. Charrette is a 1980 summa cum laude graduate of Palmer College of Chiropractic. Over the past 17 years he has lectured extensively on spinal and extremity adjusting throughout the U.S., Europe, the Far East, and Australia. In 1976, he received a Bachelor's degree from Illinois State University (summa cum laude) where he was an NCAA All‑American in 1974. Dr. Charrette is a featured speaker in Foot Levelers' 2003 Fall Seminar Series and Mega Conference Series.)