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One Size Does Not Fit All: Exercise and Nutrition According to Your Yin/Yang Body Type
There are countless new exercise and nutrition plans out there, emphasizing the latest ground-breaking research and claiming to revolutionize the way we view health.
Too Many to Remember: Tips to Revive Your Ortho / Neuro Test Skills
When I was at Palmer in the mid-1980s, we were given a set of notes in one of our diagnostic courses. The notes covered approximately 70 orthopedic and neurological tests for various regions of the body.
The Concussion-Subluxation Complex
In the Aug. 1, 2014 issue of Dynamic Chiropractic, I reviewed some of the literature demonstrating the role of the chiropractic adjustment in post-concussive care.
Mechanism: Experimental Approaches to Understanding Acupuncture, Part 1
The clinical benefits of acupuncture are difficult to ignore, but also can be difficult to explain to a Western audience. For nearly 50 years, relentlessly inquisitive scientists and physicians have been working toward a conceptual model to explain acupuncture.
Omega-3 Fish Oil: An Underappreciated Element of Men's Health
As a clinician with many male patients -- and as a man myself -- I am all too aware of the fact that we like to convince ourselves that we are doing great, when that may be the farthest thing from the truth.
Making Sense of an Increasingly Obvious Conclusion
Where's U.S. health care heading? Like it or not, the list of telltale signs is growing to a point that stands out to even the most myopic observer. Consider this list of facts as you look into the future of health care in the United States:
The Modern Application of Ancient Mei Rong
Chinese Medical Cosmetology (Mei Rong) has a well-documented and venerated history dating back to the Qin (221-206 BC) Dynasty.
Tailor-Made Knee Pain: The Sartorius Muscle
A patient was referred to my office after receiving treatment from various providers with no results. The patient was training for the Olympics as a marathon runner and was unable to run or walk without severe medial knee pain.
Syncretism: Acupuncture and Public Health in Cuba
"Syncretism" is defined as a union of diverse tenets or practices. On a recent trip to Cuba designed to demonstrate the integration of Traditional Medicine and biomedicine, our group witnessed this union firsthand.
F4CP Making a High-Impact Impression
The Foundation for Chiropractic Progress has released details of its 2016 strategy, certain elements of which are already in play. The strategy includes ads, posters and other resources available to all F4CP members.
Which Way is the Energy Going? Are You Burning Yourself Out?
One of the simple methods that I use to define Yin/Yang theory to patients is to ask the question, "Which way is your energy going?"
Diagnose Sprain Injuries in MVA Cases With Dynamic X-Rays (Pt. 1)
Am I the only person to notice hospitals are doing a seemingly insufficient job lately in their initial radiological workup of motor vehicle accident (MVA) victims?
Pro-Con: Swaddling for Newborns
The practice of swaddling has been used for thousands of years and was popular until the 1700s, when it was slowly abandoned by many cultures that considered it old-fashioned or barbaric.
Dietary Fat and Prostate Cancer: An Important Update
K.M. Di Sebastiano and M. Mourtzakis published a review paper examining the role of dietary fat on prostate cancer development and progression late last year that does a stellar job of summarizing the available data on fat and prostate cancer.
Targeting the Bad Apples in the Bunch
While everyone was focused on the conversion to ICD-10, the Office of Inspector General for Health and Human Services released a new report on chiropractic titled "CMS Should Use Targeted Tactics to Curb Questionable and Inappropriate Payments for Chiropractic Services."
Designing a Fitness Plan (Part 1)
It doesn't matter if you come to my practice for pain relief, weight loss, healthy aging or something else. The formula I talk about for each patient's fitness strategy is pretty much the same.
Acupuncture Rising: From Acupuncture Anesthesia to Assisted-IVF, Part 2
Acupuncture's cultural and historical roots go back to the emergence of Chinese civilization. For more than 2,000 years, acupuncture needling has been continuously practiced on the largest population in the world.
Footsteps of the Sages: An Apprenticeship with Dr. Kezhan Zhang
When I met Dr. Kezhen Zhang in May 2013, I was his translator and the integrity, creativity, and passion he demonstrated as a practitioner and advocate of the medicine convinced me to travel to Beijing to study with him.
Born to Energize the Human Spirit: Recollections of Sig Miller
Sig Miller, longtime executive director of the Association of New Jersey Chiropractors (ANJC), passed away on Sept. 17 after a long battle with cancer.
Your Billing Questions Answered
I hear a lot of the following questions: I am afraid I may doing something illegal. I have heard I cannot have different fees for the same service.
It's Time to Review
It is amazing to see the changes that are occurring in the acupuncture profession. Let's look at some of the news and events that have contributed to this growth and awareness.
Chinese Herbs and Pulmonary Fibrosis: A Case Study
"Mary M."* recently celebrated her 90th birthday. Even the former sheriff dropped by to kiss the hand of this diminutive retired teacher, to honor the years she interpreted for him during interviews with Latinas and Latinos.
Acupuncture and Oriental Medicine in the West
We know acupuncture and Oriental medicine as the indigenous medicine of East Asia; in particular China, Korea and Japan are the countries of origin of this wonderful healing system.
North Carolina Acupuncture Board Files Dry Needling Lawsuit
In early September, the NCALB filed a complaint against the North Carolina Board of Physical Therapy Examiners over the issue of dry needling, a form of acupuncture that uses solid needles to puncture the skin and muscle tissue to relieve pain.
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 previous articles by Erik Dalton, PhD.
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