December 2003

Shoulder 'pronation' and orthotic support

by Dr. Mark Charrette

There is a fine interplay between the movements of the lower extremities and the balancing of the spine.

Normal gait causes repetitive motions to occur from the feet up to the head. [1]

Alignment and function of the pelvis, spine, shoulders, and head are strongly influenced by pedal balance or imbalance.

Foot imbalances, such as excessive pronation and metatarsal arch collapse, cause postural problems with far‑reaching effects that can even include shoulder unleveling.

Effects of pedal instability

Pelvic misalignments.As a foot pronates during the stance phase of gait, there is a normal inward (medial) rotation of the entire limb and pelvis.

In persons who have excessive or prolonged pronation, this twisting movement is accentuated. The increased rotational forces are transmitted into the pelvis and sacroiliac joints. [2]

In response, various compensatory pelvic subluxation complexes develop. These include pelvic tilts, innominate rotations, and other complicated adaptations.

Until the excessive pronation is corrected with custom‑made orthotic supports, only short‑term relief can be achieved with chiropractic adjustments.

Muscle imbalances. Many chronic myofascial problems can begin with excessive foot pronation.

The associated gait abnormalities, neurological incoordination, and asymmetrical structural stresses are often compensated by contracting the large stabilizing muscles of the spine and shoulders.

This results in habit patterns with detrimental effects on movement and eventual perpetuation of symptoms.

Myofascial trigger points in the upper quadrant, chronically contracted shoulder muscles, and even thoracic outlet syndrome [3] can develop when gait abnormalities continue.

Neurological effects. The feet are very well supplied with proprioceptive nerve endings.

Mechanoreceptors in the joints, along with the muscle spindles of the foot muscles, are responsible for the positive support reflexes and a variety of automatic reflexive reactions. [4]

The position receptors in the feet, spine, and especially the neck (head‑righting reflexes) must coordinate smoothly in order to maintain postural equilibrium.

Difficulty in keeping optimal postural and shoulder alignment, and/or problems with excessive postural sway, are frequently caused by inaccurate information sent by spindle sensors in chronically strained muscles or by joint mechanoreceptors. [5]

Whenever there is an unequal amount of support from each leg during weightbearing stance (due to either an anatomical or a functional shortening), posture will definitely suffer.

This results in an uneven foundation for the pelvis and the spine, causing postural shifts, such as unlevel shoulders, in response.

The coordination of the lower extremities during gait is a critical aspect of shoulder function. [6]

At the same time that gravity and ground reaction forces are affecting the legs and feet, the torso and shoulder are also responding.

With each step, the scapula reacts to opposite‑leg loading by tipping anteriorly in the sagittal plane, rotating upward in the frontal plane, and gliding around the ribcage in the transverse plane (protraction).

'Shoulder Pronation.' This reaction produces the appearance of a hunched and forward‑rounded shoulder, and can be described as 'shoulder pronation.'

The biomechanical and neurological processes that link shoulder pronation to lower extremity pronation on the opposite sides help us understand how unlevel shoulders can be indicators of asymmetrical foot function.

The importance of gait

As the leg is loaded in gait, trunk side‑bending occurs to the loading leg.

The lumbar spine rotates away from the loaded leg, and a balancing rotation occurs in the thoracic spine to the same side as the loading leg.

The scapula then slides forward on the ribcage into the protracted position.

It is the eccentric loading of the periscapular muscles that controls this scapular reaction, and the shoulder is now ready to retract with efficiency.

The entire relationship of the shoulder and thoracic spine is driven by the cross‑crawl neurological reaction to gait.

There are also common hip motions that can function as "cheaters" for the shoulder. This occurs when the shoulder muscles are weak, fatigued, or overloaded.

The strength of the large muscle mass around the hip can substitute and alter the mechanics to the weakened shoulder muscles' benefit.

For instance, transverse plane activity (such as external rotation of the shoulder with exercise tubing) is assisted by opposite hip internal and external rotation.

This means that excessive pronation on the opposite leg can interfere significantly with normalization of the neuromuscular balance between the internal and external rotator muscles of the shoulder.

To address this, custom‑made, corrective orthotics which limit pronation are often needed to fully rehabilitate shoulder injuries and chronic symptoms.

Conclusion

Because a smooth and symmetrical gait is tied so closely to proper vertebral function, biomechanical problems in one or both feet can interfere with postural alignment patterns.

Many spinal and postural complaints, including shoulder unleveling, have foot dysfunction as an initiating or an associated factor.

Posture, balance, coordination, and efficient musculoskeletal function all depend on the smooth functioning of the foot and ankle complex.

Whenever a patient demonstrates a postural imbalance with unlevel shoulders, we must always consider the importance of the lower extremities, and the feet in particular.

References

1. Yekutiel MP. "The role of vertebral movement in gait: implications for manual therapy." J Man Manip Ther 1994; 2:22‑27.

2. Botte RR. "An interpretation of the pronation syndrome and foot types of patients with low back pain." JAPA 1981; 71:243‑253.

3. Sucher BM, Heath DM. "Thoracic outlet syndrome ‑‑ a myofascial variant: structural and postural considerations." J Am Osteopath Assoc 1993; 93:334‑345.

4. Freeman MAR, Wyke BD. "Articular contributions to limb muscle reflexes." J Physiol 1964; 171:20.

5. McPartland JM, Brodeur RR, Hallgren RC. "Chronic neck pain, standing balance, and suboccipital muscle atrophy ‑‑ a pilot study." J Manip Physiol Ther 1997; 20:24‑29.

6. Walendzak D. "Lower extremity theory enhances shoulder rehabilitation." Biomechanics 1998; 5(10):45‑51.

(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.)

December 2003

Results: Past, present and future by Dr. Eric Plasker

Here we are at the end of 2003 and quickly about to leap into what will be an exciting 2004. This time of year is well known for its opportunity to reflect on past achievements, examine where we currently are in our practice and map out our goals for both the near and long‑term future.

A wise person once told me, "You are not your results. You are your commitment!" This is a very powerful statement. Have your results from the past year met what you are capable of doing, if you were truly committed to your efforts?

I wonder how many of us can honestly say that we have focused on our goals every day. Even if we have met our initial goals, were they set to the level that we would be truly capable of achieving with 100% commitment?

Ask yourself whether you have been focused on making a difference in peoples' lives by providing the highest quality of care. Can you say this with a heartfelt, "yes" or have you been focused on survival and complacency during 2003?

If you want this next year to be the best year you have ever experienced, start thinking about what changes you need to make in order to create the results you desire ‑‑ and make your commitments NOW!

While you're asking yourself these questions, how about a few more? See what answers you come up with when you ask yourself: What commitment are you willing to make to become a better healer? What commitments will allow you to run your practice more effectively? Can you commit yourself to keep your integrity high while you reach your goals? What do you need to do to grow your practice and what help do you need to reach each level?

Forward thinking chiropractors focus on their goals and commit to achieving them. People who are not committed to achieving their goals function much differently. Are you a committed individual who wakes up every morning with a mission? Is your commitment more important than watching television, being liked or accepted by those around you, and just surviving? Answer these questions honestly.

Committed people walk a little faster, are more decisive and not afraid to make a mistake. One thing that I am sure of is that 2004 will be the best year for many, many chiropractors.

The world is ready to embrace the holistic principles of chiropractic. We see this all around us as millions are already utilizing chiropractors as their family's primary health care provider. Set a goal to make the family focus a priority, and commit to delivering lifetime chiropractic to everyone.

It's been an incredible year for The Family Practice D.C.s. Our Systems Library has been distributed all over the world and has helped chiropractors everywhere to reach their goals, both professionally and personally.

And, 2004 is primed to be an even greater year than the last for every doctor who's committed to being a family health care provider and leader. You can be one of those life‑changing chiropractors.

YOU can be the chiropractor that you have committed yourself to be.

Have a happy and healthy New Year.

(Nationally recognized speaker, educator, and author Dr. Eric Plasker is the founder of The Family Practice, a premier chiropractic coaching and training organization dedicated to making chiropractic the number one health care profession in the world. Dr. Plasker invites you to add the next Family Practice Seminar to your commitment for 2004.

For information on The Family Practice Systems Library, a seminar schedule, coaching, training, or other product information, call The Family Practice toll‑free at 866/532‑3327, ext. 118. Or visit The Family Practice website at www.thefamilypractice.net.)