resourcesABOUT MT AUTHOR GUIDELINES CLASSIFIEDS EDITORIAL CALENDAR MEDIA GUIDE MASSAGE MART SCHOOLS & EDUCATION FEEDBACK
The Acupuncturist's Problem
I want share with you some observations and insights into what seems to be the most common problem my colleagues in the acupuncture profession struggles with. If you also struggle with this problem, I hope you get a valuable "aha" moment from reading this.
Animal Acupuncture: A Case Study in the Treatment of Traumatic Injury in the Equine
The rise of animal acupuncture in the U.S. began in the early 1970's as a result of the work by members of the National Acupuncture Association in Westwood, Calif.
5 Simple Steps to Create an Effective Marketing Calendar
In the educational experience of most healthcare practitioners, business and marketing are overlooked topics.
Green Tea Improves Cognitive Function in Elderly Subjects
Publishing their results in the journal Nutrients in May 2014, researchers showed that drinking the equivalent of 2-4 cups of brewed green tea (or bottled tea) daily improved cognitive function or reduced the progression of cognitive dysfunction in elderly subjects.
Medicine is Clumsy, Don't You Be
All medical systems have clumsiness in them. If the technique isn't, the practitioner is. Everyone in every form of medicine is striving to improve. That is why we call it practice.
Spieth Thanks His Chiropractor After Historic Masters Win
Jordan Spieth didn't just capture the hearts of golf enthusiasts worldwide with his record-setting, wire-to-wire victory at the 79th Masters Tournament.
How Much Do You Know About the Benefits of Birds Nest?
Edible bird's nest is the nest made by the Swiftlet bird of Southeast Asia that is usually prepared as a soup and prized in Chinese culture as a healthful delicacy.
We Get Letters & Email
A House Divided? (May 1 issue) provoked significant response from readers. Here are several of the surprisingly similar comments we received.
Professional Credentialing and Board Certification: An Ethical Faux Pas
Because of the Affordable Care Act, health care systems are coordinating care through accountable care organizations (ACOs) in order to reduce the cost of care and improve quality of care.
Our Biggest Challenges to Compete in Wellness Care
In the first article in this four-article series [May 1 DC], I made the case that chiropractors should either embrace offering lifestyle wellness in their practices or face the possibility of losing their place in the wellness care marketplace.
A Poor Choice for Pain Relief
Acetaminophen is the most popular pain reliever in the U.S., accounting for an estimated 27 billion annual doses as of 2009. With 100,000-plus hospital visits a year by users, it's also the most likely to be taken inappropriately.
The Tide is Rising in the Acupuncture Profession
Former President Ronald Regan said, "When the tide rises all boats float." The tide is rising for the acupuncture profession. Many forces outside the profession are helping the tides to rise.
Integrating Art with Clinical Practice for Patients with PTSD: The Artemis Project
Are you restricted by those one-on-one clinic dynamics? Why not join colleagues and clients in experimental group settings? Three of us volunteered to do just that in Austin on behalf of women veteranss from all branches of the service.
PCOM Granted Regional Accreditation
Pacific College of Oriental Medicine (PCOM) recently announce it has received regional accreditation from the Western Association of Schools and Colleges (WASC). This achievement reflects five years of hard work on the part of faculty, staff, and students.
First Do No Harm?
There's no questioning the frightening nature of breast cancer, which strikes one in eight women in the U.S. – eclipsed only by skin cancer in terms of prevalence.
The Challenges of Integrating Eastern and Western Medicine
My Masters thesis was titled, "The Challenges of Integrating Eastern and Western Medicine," which highlighted several reasons why it is hard for these two worlds to mix.
ACA or ICA: Which Best Represents You?
Last June, I was honored to represent Texas ICA members as their representative assemblyman at the ICA Annual Meeting in Kansas City.
Giving Vets the Care They Deserve
The Department of Veterans Affairs (VA) administers the largest integrated health care system in the United States.
5 Tips for Using Pinterest to Market Your Practice
Pinterest is a very popular, but often under-utilized, social media platform where people can bookmark, or "pin," fun and interesting things from all across the internet.
Rethinking Musculoskeletal Pain – A Public Health Perspective
The American Public Health Association (APHA) is the world's oldest and largest association of its kind, founded more than 140 years ago and boasting over 25,000 members.
Leg-Length Inequality and Pelvic Fixation: A New Approach to the Negative Derifield (Part 2)
As we noted in our previous article, with a positive Derifield (+D), the doctor observes the reactive (shorter) leg in the prone position that becomes longer or "crosses over" in the flexed position.
Reducing the Autogenic Inhibition Reflex: Making Weak Muscles Strong
The autogenic inhibition (AI) reflex is a sudden relaxation of a muscle in response to excess tension.
August, 2008, Vol. 08, Issue 08
Don't Get Married, Part 2
By Erik Dalton, PhD
Humans are designed to move in order to survive - locomotion must precede all other activities. The past few decades have witnessed the emergence of two diverse schools of thought, each with their own biomechanical explanations detailing the seemingly simple act of walking.
Both disciplines generally agree that cross-patterned gait (opposite arm and leg moving at the same time) is a normal function of walking and running. However, advocates of the traditional "pedestrian model of gait" insist the legs are the main-event in locomotion and upright walking is a basic design where the legs propel the passive passenger - the trunk - through space. Pedestrian model groupies tend to lump the torso, arms and head together and generally dismiss the upper body as a critical player in gait mechanics.
As discussed in part 1 (Feb. 2008 issue), Canadian nuclear physicist Serge Gracovetsky, PhD, rebuked the pedestrian model by declaring that counter-rotation of the shoulders and pelvis is an essential key to locomotion and force is not generated by the legs, but instead arises through a complex muscle/skeletal interaction propelled by what he calls a "spinal engine."1 He further explains, "Evolutionarily, locomotion was first achieved by the motion of the spine. ... The legs came afterward as an improvement, not as a substitute."
If Gracovetsky's theory that the spine is the primary engine driving the pelvis has "legs to stand on" (no pun intended), then manual therapy assessments and rehabilitative corrections must be modified accordingly. Since low back pain is the most common disability among people under the age of 45, the consequence of this reinterpretation of spinal function could be far-reaching. Today, researchers and clinicians worldwide are experimenting with Gracovetsky's intriguing hypothesis.
Tempted to Marry
Since both schools of thought are supported by sound research in the gait-analysis community, I'm trying hard not to marry a single model of locomotion. To prevent the suffering that accompanies divorce, I've developed assessments and corrections based on gait studies conducted by two renowned experts in the field, Serge Gracovetsky and my mentor, Philip Greenman.2 This osteopathic and physics collaboration paints a broader, more comprehensive picture of the walking cycle. Unfortunately, in the process of marrying the two methods, some of Gracovetsky's brilliant spinal-engine concepts have been altered. To avoid misrepresenting the views of either researcher, the proposed model in part 2 will simply be referenced as the "myoskeletal engine."
The Myth of Leg Locomotion
Dr. Gracovetsky convincingly asserts, "If the legs were truly the mobilizing force propelling the body through space, a competitive sprinter with huge powerful legs and a small torso should be the fastest." (Figure 1) Obviously, this image does not fit the picture we'll see at the Beijing Olympic Games or even in the photo of a 21-year-old South African double-amputee runner Oscar Pistorius, who finished second against the world's top athletes in a 400-meter race at the Golden League Meet last year in Rome. (Figure 2)
Initial observation of Pistorius' stride reveals a rhythmic cross-patterned gait and strong pelvic/shoulder counter-rotation that appears as the driving force propelling his lower extremities. Figures 3A and 3B illustrate global and core muscle "slings" that store and release kinetic and elastic energy that help him run at such high speeds. In the absence of lower legs and feet, one might conclude these anterior and posterior spring systems alone provide enough thrust to propel Pistorius' pelvis and extremities. But apparently, the International Association of Athletics Federations (IAAF) disagreed. They voted to ban him from formal competition based on the conclusion this artificial "springing" mechanism somehow amplified his interaction with gravitational ground forces.
Appeals to the Court of Arbitration for Sport (CAS) and subsequent studies confirmed the carbon-fiber blades did not give him an unfair advantage. So, does Pistorius run fast because of the recoil delivered by curved blades, or are humans endowed with a similar recovery pulse capable of transmitting gravitational forces up the kinetic chain to enhance power in the other spring systems?
Flat Tire - Flat Foot
Since the human body relishes energy conservation, it's reasonable to assume kinetic (movement) energy shouldn't be lost into the ground as described in the pedestrian gait model. Gracovetsky uses the analogy of running in sand versus on a firm surface to make a point that efficient movement demands a recovery pulse that springs from the arch, up the leg and through the pelvis and torso to help drive the spinal engine. Furthermore, it makes sense that any "kink" along this myofascial or skeletal (myoskeletal) chain would be reflected as a kink elsewhere in the system that would only serve to slow down the engine.
For example, if a car has a low tire and the tread begins wearing unevenly, the vehicle will begin to shake sooner or later. As the vibration makes its way through the suspension system, the tie rods start working loose. If left untreated, damage spreads to the motor mounts. Eventually, the "shaky" engine sputters to a halt. Although the low tire was the root of the problem, it's tempting to blame the engine because the car no longer runs.
In this regard, it's easy to see how a deflated tire might perpetuate a chain of events manifesting as compensations elsewhere. To remove kink(s) from the system, an experienced mechanic won't immediately pull the hood and begin checking for loose spark plugs and battery cables. Tracking down the dysfunction typically starts by consulting with the owner, conducting a thorough history of onset, symptoms, etc., and then performing a detailed inspection that leads to the "key lesion" - the low tire. From information garnered during the evaluation process, the mechanic is able to systematically work their way though the suspension system, motor mounts and fuel-injection system to restore optimal motor functioning.
The same applies to the client with a flat foot and short leg. A good body mechanic doesn't treat a hyperpronated foot in isolation but looks for compensations along the kinetic chain that might have developed as a result of the shortened extremity. Kinks traveling from the head down (TMJ, O-A, scoliosis, cranial distortion, etc.) are labeled descending syndromes, while asymmetry caused by pronated feet, short legs, knock-knees, etc. are referred to as ascending syndromes. (Figure 4) Any soft-tissue or bony compensation that distorts the vertebral column's S-shaped curve will overwork the anterior and posterior spring systems, resulting in stress and pain.
Stirrup Spring System
The automobile analogy provides a nice segue for introducing a third biomechanical "sling" critical in driving the myoskeletal engine. Known as the stirrup spring system (SSS), this antigravity propulsion pump delivers energy from the tibialis anterior/peroneus longus stirrup through the biceps femoris and sacrum to provide rotary torque that "winds up" intervertebral joints and deep collagen structures. Figure 5 depicts a few key SSS muscles activated during running. Although, I agree with Gracovetsky that efficient movement requires humans to possess some kind of recovery pulse to avoid loss of kinetic energy into the ground during gait, the biomechanics of how that pulse is delivered is debatable.
Gait analysis is best understood when viewed just prior to heel strike, as illustrated in Figure 5. For the SSS to achieve optimum elastic recoil, two neurologically driven maneuvers must orchestrate in perfect harmony. With hip extensors (biceps femoris and G-max) maximally stretched:
Walking and running trigger various degrees of force through the stirrup, knee, lateral thigh, biceps femoris and sacrotuberous ligament. The amount of force at heel strike determines how much lumbopelvic counter-rotation takes place and what muscles/ligaments are recruited. Once the pulse reaches the pelvis, the mechanics become more complex.
At this point, Gracovetsky and I part ways. He believes the recovery pulse at right heel strike possesses sufficient strength to travel unimpeded up the leg, through the sacrotuberous and long dorsal sacroiliac ligaments, and into the ipsilateral multifidi, longissimus and iliocostalis. Erector spinae contraction then causes right lumbar sidebending and reciprocal pelvic counter-rotation. Although this intriguing firing order does play a major role in running, it differs a bit from my interpretation of Greenman's heel strike mechanics during walking.
Myoskeletal Engine Possibility
Notice in Greenman's illustration (Box 1, Figures 1 and 2) at right heel strike, the sacrum, pelvis and lumbar spine are all left rotated. This implies that during the walking cycle, heel strike probably doesn't transmit adequate force to sidebend the lumbars and counter-rotate the pelvis, as Gracovetsky infers. A myoskeletal-engine firing order that seems to best fit Greenman's illustration has the stirrup pulse traveling through the biceps femoris and sacrotuberous ligament, tugging on the lateral sacral angle, and (with help from the quadratus femoris and G-max), left-rotating the entire pelvic bowl in a transverse plane.
Gracovetsky's spinal engine theory is based on the assumption humans possess no muscles capable of directly rotating the pelvis. But if one follows the chain of events beginning at heel strike to the stance phase, it appears the sacrum and pelvis perform complex maneuvers enhanced by many smaller but extremely important muscles that do possess the capability to directly and indirectly rotate the pelvis. At first glance, it seems an insignificant point, so long as the final result is a smooth cross-patterned gait. However, it implies the possibility of a different SSS firing-order pattern traveling through the lumbopelvis and thus the need for alternative assessment and treatment sequences.
Stance Phase Is True Coupled Motion
The myoskeletal SSS theory relies on Harrison Fryette's 1st Law of Spinal Motion3 which (paraphrasing) states that in the presence of normal lumbar lordosis, vertebral and sacral rotation and sidebending occurs to opposite sides. (Figure 6) Gracovetsky believes this coupled motion takes place at heel strike and I see it happening during the stance phase. In my model, the following actions occur during the one-legged stance phase (right limb):
Last, but not least, the lateral spring system (LSS) depicted in Figure 8 might be one of the most unappreciated of all the body's antigravity structures.
Driven by the hip's abductors, this elegant myofascial gait-enhancer "cocks' the ipsilateral innominate and, just prior to push-off, right-sidebends the rotating pelvis so the other three spring systems can smoothly swing the left leg through. (Box 1, Figure 5) All is well if gluteus medius and minimus are properly toned and firing in correct sequence. Regrettably, this spring system commonly is skewed as other abductor muscles overpower the weak glutes.
Figure 9 illustrates the need for greater contralateral OL recruitment in athletes such as hurdlers and running backs. However, during normal gait, both quadratus muscles should be relatively silent. Thus, the ideal abduction firing-order pattern from stance through toe-off should be: gluteus medius/minimus; co-contraction of the ipsilateral adductors; tensor fascia latae; piriformis (synergistic stabilizer) and quadratus lumborum.
A greatly underestimated source of discogenic and facet joint pain arises when the ipsilateral QL fires first, "hip-hikes" the innominate, and forces the ipsilateral leg to try to swing through.
These people walk like a block with a labored gait. Seen in many golfers and other athletes who participate in one-sided sports, this common QL substitution pattern is quite easy to assess and correct. Figures 10A and 10B demonstrate two QL releases that help drag down a hip-hiked (posteriorly rotated) ilium. Unfortunately, fixing the QL problem won't completely restore proper firing order if the glute medius/minimus are weak. Fast-paced spindle-stim techniques and "clam" home re-training exercises using resistance tubing are a simple solution. Although most clients like deep gluteal massage and stretching, these traditional bodywork maneuvers alter the hip-abductor firing order and destabilize the pelvis. Weak glutes = future hip replacements.
Sports and the Spring Systems
Many athletes (and therapists) believe if a little stretch is good, more is better. Bombarding the physiologic barriers through over-stretching and excessive deep-tissue work not only jeopardizes ligamentous stability, but also causes loss of recoil and balance in the body's intricate spring systems. No one questions that chronically shortened (fibrosed) tendons, fascia, ligaments and joint capsules require restoration of flexibility, but what about weak, overstretched and neurologically inhibited tissues? Certain structures such as the thoracolumbar and lower abdominal fascia must retain a certain amount of stiffness to store and release elastic energy while providing core stability. Myofibroblast receptors embedded in deep fascial tissues might prove to be the missing link responsible for enhancing power in the four spring systems.4 See Box 2 for spring-system balancing tips.
Fast-paced myoskeletal spindle-stimulating techniques combined with Vladimir Janda's upper- and lower-crossed syndrome balancing routines are a complementary and essential starting point in the myoskeletal engine method. Tonifying typically weak muscles via "spindle-stim" maneuvers and home re-training exercises helps establish proper firing-order patterns while restoring cross-patterned gait. Loss of reciprocal (coupled) motion between the lumbar spine and sacrum probably is the leading cause of chronic low back pain. A testament to this assertion is the fact the L5-S1 intervertebral disc receives more surgical procedures than any other spinal segment. Bottom line: Discs hate sustained compression but love storing and releasing rotary torque.
The theoretical approaches presented in this two-part series represent an ongoing personal journey into the captivating world of gait. Attempting to blend Gracovetsky and Greenman's gait-analysis theories has opened a Pandora's Box of additional inquiries questioning how ascending and descending syndromes (flat feet, TMJ, knee injuries, etc.) destabilize pelvic and lumbar spine balance. What seems clear is the necessity for restoring perfect coordination and antigravity function to all four spring systems. Energy conservation during walking or running demands all systems fire in a precise order at just the right moment to accomplish this task. I've become married to the idea that all the body's global and core structures must work harmoniously to produce rhythmic and effortless movement during normal activities and athletic endeavors. Try experimenting with spring system balancing routines and elevate your hurting clients and competing athletics to a new level of health.
Click here for more information about Erik Dalton, PhD.
Join the conversation
Comments are encouraged, but you must follow our User Agreementcomments powered by Disqus
Keep it civil and stay on topic. No profanity, vulgar, racist or hateful comments or personal attacks. Anyone who chooses to exercise poor judgement will be blocked. By posting your comment, you agree to allow MPA Media the right to republish your name and comment in additional MPA Media publications without any notification or payment.