The Pettibon System

The Pettibon System is a full spine correction method built on a single premise: the muscles, ligaments, and discs decide whether an adjustment holds. Burl Pettibon assembled it in Washington State across six decades, beginning with upper cervical radiographic analysis in 1956 and ending with a patented catalog of rehabilitation equipment. Its governing claim is that the patient’s nervous system performs the correction, not the doctor’s hands. The doctor’s job is to give that nervous system a reason to do it.

Burl Pettibon trained in upper cervical analysis, then rebuilt the entire office visit around it

Burl Rex Pettibon was born on the family homestead in Deerfield, Missouri on November 13, 1932. After military service he enrolled at Cleveland Chiropractic College in Kansas City and took his degree in 1956. That same year he attended a seminar taught by John F. Grostic and carried Grostic’s upper cervical radiographic analysis back to Washington State, where he opened a practice in Tacoma. He died at home in Chehalis, Washington on December 22, 2017, at 85.

What turned an upper cervical practitioner into a systems builder was his own body. William H. Koch began studying with Pettibon in 1971 and was certified as an instructor in 1977. Koch records that Pettibon skied, raced cars, and rode motorcycles. Along the way he collected fractured limbs, severe spinal injuries, and a broken neck. When the best techniques available could not hold his own corrections, he concluded that the problem was mechanical rather than anatomical.

By Koch’s account he then took that problem to the engineering faculty of a university. He described a hypothetical machine with a given number of moving parts, a given range of motion, and a given weight bearing and lifting capacity, and asked how it could be built. The engineers told him it was impossible. He replied that it already existed and worked well, and that it was the human spine. He founded the Pettibon Biomechanics Institute to answer the question properly.

The Pettibon System’s chronology runs from a 1956 seminar to a 2008 patent

1956 to 1969: Grostic’s lines, then Pettibon’s own

Pettibon practiced Grostic analysis in Washington after his 1956 seminar, and the instruments and lines of that school stayed with him. In 1956 the Dallas orthopedic surgeon Ruth Jackson published The Cervical Syndrome, which analyzed whiplash stress by drawing lines along the posterior bodies of C2 and C7 on the lateral radiograph. During the 1960s Pettibon began teaching those as the superior and inferior Pettibon stress lines. His fidelity to the source is documented: his own 2001 patent application still names them Jackson’s stress lines, forty five years after her book.

1970 to 1979: an instrument, then the whole spine

Pettibon filed a design patent for a precision cervical vertebrae adjusting instrument on June 19, 1970, from 1002 Monterey Lane in Tacoma. It issued as US D223,419 on April 11, 1972. In the early 1970s he extended Grostic type radiographic lines to the anteroposterior Ferguson view. He also carried Jackson type lines to the lateral lumbar film at L1 and L5. Low back procedures followed. Sharon Pettibon later put the consequence plainly: Pettibon is not an upper cervical technique, because the whole spine is filmed and the whole spine is adjusted.

Teaching scaled in the same decade. Donald D. Harrison recorded that his first Pettibon seminar, held in Dan Beeson’s clinic basement in Portland, Oregon around 1976, drew twelve students. Harrison taught the Portland seminars from the fall of 1977 through March 1979, and attendance over those years ran twelve, twenty, forty, sixty, eighty, and finally 120.

1981 to 2004: the Institute, the equipment, and the name

Pettibon founded the Pettibon Institute as a nonprofit organization in 1981, dedicated to research and education. The rehabilitation hardware that now defines the method arrived later. From 1991 onward he designed and introduced the Wobble Chair and the Linked Exercise Trainer. The Negative Z skull on atlas adjuster followed, along with the Pettibon Weighting Systems, the Pettibon Tendon Ligament Muscle Stimulator, and a series of traction devices. In 2004 the corporate names caught up with the clinical ones. Pettibon System, Inc. replaced Spinal Technologies Company, and the Pettibon Bio-Mechanics Institute became The Pettibon Institute. The company was in Gig Harbor through at least 2011 and manufacturing in Chehalis by August 2013.

2000 to 2008: four patents that fix the protocol in writing

Pettibon patented the rehabilitation program itself, which is why its numbers can be checked. US 6,481,795, the therapeutic chair, was filed June 5, 2000 and granted November 19, 2002. US 6,517,506, the cervical traction device, was filed October 5, 2001 and granted February 11, 2003. US 6,788,968, covering the weighting system and its examination method, was filed October 16, 2001 and granted September 7, 2004. US 7,322,977, a spinal adjusting device, was filed December 11, 2002 and granted January 29, 2008.

Pettibon’s core contribution was making soft tissue the thing that holds the correction

Most chiropractic techniques in the twentieth century argued about where to push and how hard. Pettibon argued about what happens in the other 23 hours of the day. His position, stated on his own materials, is that muscles are responsible for the integrity of all joints and therefore for the position of the upright spine. A corrective procedure without muscle rehabilitation, he held, has no chance of producing permanent correction.

That claim reorganizes the visit. If the tissue decides, then warming it before the adjustment is not a courtesy. It is part of the adjustment. On the same logic, twenty minutes of home work twice a day is not compliance. It is the treatment. The Pettibon System’s equipment catalog exists because the method assigns most of the corrective work to hours the doctor is not present for. From 1991 he built the hardware that made that assignment possible.

Pettibon rejected the idea that an adjustment alone can hold a spine

In a paper he titled Historical Perspective, Pettibon wrote that it became increasingly apparent to him that chiropractic techniques could not produce permanent spine and postural change. He describes beginning research with Vern Pierce to determine what chiropractic procedures actually did. Pierce went on to found Pierce-Stillwagon with Glenn Stillwagon in 1963, on a parallel conviction that a correction has to be verified rather than assumed. His conclusion was blunt: the living spine cannot be permanently changed by adjusting, manipulation, or bracing.

His stated reason is the stretch reflex. When a muscle is suddenly stretched, a strong signal reaches the spinal cord and the same muscle contracts back. Pettibon held that this reflex is why fast corrective forces are given back, and that many procedures taught in chiropractic colleges produce only a small increase in range of motion. He did not conclude that correction was impossible. He concluded that the patient’s own organizing energy can hold a corrected spine, and that the doctor’s task is to produce a change the nervous system will then adopt.

The five righting reflexes are the mechanism the Pettibon System recruits

Pettibon’s answer to his own objection was to stop fighting reflexes and start recruiting them. His patented weighting method is written around five righting reflexes. Three are the labyrinthine reflex from the inner ear, the optic reflex, and the neck righting reflex from cervical joint receptors. Two more are body righting reflexes, one from surface receptors and one relating head to body. These reflexes hold the head upright against gravity. Pettibon’s claim is that the lower spine is aligned or displaced as needed to serve them.

The mechanism has a peer-reviewed statement with Pettibon’s own name on it. Morningstar, Pettibon, Schlappi, Schlappi, and Ireland published a 193-reference review of postural reflexes in Chiropractic and Osteopathy in August 2005 (PMID 16091134). It catalogs visual, labyrinthine, neck, body on head, and body on body righting reflexes. Its conclusion reaches past the technique. The paper argues that vertebral misalignments are not random injury-induced events, but the consequence of an adaptive postural process mediated by the nervous system.

The initiating event is at the skull, and the rest of the spine answers it

Pettibon named the whole pattern the spinal system subluxation complex, and traced it to what he called an initiating event subluxation. He held that when the skull locks in extension on the atlas, the result is forward head posture and loss of the cervical lordosis. When the skull locks in flexion on the atlas, the cervical curve buckles into an S shape with the lower cervicals going kyphotic. His 2001 patent divides the global spine into six functional units: skull, cervical, thoracic, lower thoracic, lumbar, and sacral. It sets the geometric target as the center of the head aligned over the front of the C4 to C5 disc.

A Pettibon visit warms the spine before anyone adjusts it

The wobble chair, the traction unit, and the fulcrums come before the doctor

Patients arriving at a Pettibon clinic go to equipment, not to a waiting room. The Therapeutic Wobble Chair is a saddle seat on a universal joint. Its patent specifies 360 degrees of rotation, 40 degrees of side to side flexion, and 35 degrees of front to back flexion, and the current chair is tested to 300 pounds. The patient holds the head and shoulders still and moves only the pelvis, front to back, side to side, then clockwise and counterclockwise. One published protocol ran twenty repetitions of each, eighty per visit.

Repetitive cervical traction runs alongside it. The patient hangs partial body weight from a padded strap that sits under the chin or across the forehead. The strap is suspended level with the shoulders, and the legs work the load. The traction patent prescribes six to eight repetitions on the first day, rising to thirty, and to sixty within fourteen days, each repetition held for a slow count of ten. Pettibon’s company caps the hanging load at 20 percent of body weight. Foam fulcrums complete the sequence, molding a curve under passive load for up to twenty minutes.

The warm-up has a clock on it. Pettibon System instruction is that the patient should be adjusted within six minutes of finishing the warm-ups, while soft tissue resistance is still low. That six minute window is the clearest statement of the method’s logic: the same force applied to a cold spine and a warm spine is not the same input.

The adjustment is delivered by instrument, by hand, and by strap

The Pettibon System adjusts with tools built for the job. The Multiple Digital Toggle is a solenoid driven instrument that delivers a single toggle or a timed train of them, with force settings that span an infant’s neck and a large adult. Its design principle is speed: the thrust must be faster than the muscle’s reactive response, so the body accepts the input rather than guarding against it. The Negative Z adjusts the skull on the atlas. The Pettibon Tendon Ligament Muscle Stimulator applies a rapid vertical force that tractions ligament, muscle, and tendon.

The Y Axis Traction Strap is the Pettibon procedure that went viral on social media. Pettibon created it, and he wrote the rules for it. Warm-ups always precede it. On a first treatment the practitioner applies the traction without the tug at the end. The stretch may be held for 40 seconds up to three times in one visit, with a 20-second rest between. Supine leg length is checked before and after as the visit’s own verification.

Weights turn the correction over to the patient’s own muscles

Head, shoulder, and hip weights are the part of the Pettibon System that does the correcting. A frontal head weight rotates the skull and eyes upward. That rotation activates the optic and labyrinthine reflexes and the neck joint receptors. The cervical flexors then pull the skull back and down until the eyes are level. Shoulder and hip weights are each at least double the head weight, and as much as 80 percent of a shoulder or hip load is placed on one side to drive a rotation.

Dosing is written into the patent. Introductory head weight is commonly two to six pounds, with more added to tolerance, and the weighted lateral radiograph selects the final figure. The patient wears the weights upright for at least twenty minutes at a time, twice a day, for ninety days. Pettibon’s stated rationale is ligamentous creep: muscles hold the new position while discs and ligaments reform into it under sustained low load. A published case protocol added a ten minute treadmill walk in a four pound head weight before a follow-up film.

Pettibon equipment is documented by four patents and a Class I device registration

The Pettibon System holds an FDA establishment registration, number 3005033444, at Chehalis, Washington. Eight device listings sit under it, all Class I. Four went on the list on August 11, 2005: a non-powered traction apparatus, an electric therapeutic massager, exercise components, and a non-measuring exerciser. A therapeutic vibrator was added on December 13, 2006. Cervical and lumbar orthoses were added on February 16, 2016. Registration, listing, and four granted patents are the documentary record for this equipment, and they are what the description above is built from.

Where the Pettibon System meets the Unified Model of Tone

The Unified Model of Tone holds that tone is the organization of the living system, and that the nervous system is its highest-density integrator. It also holds that no single lynchpin exists through which the whole body must be reached. Pettibon held that there is an initiating event at the skull, and that the rest of the spine arranges itself to serve it. Neither claim is softened to fit the other. The reading that holds them is that Pettibon found one real doorway and described it precisely. The reason his doorway works is the reason Gonstead, Diversified, and thirty other methods also work.

Righting reflexes are the body sampling its own position

Pettibon’s five righting reflexes are, in the model’s terms, the body’s measurement of where it is. Inner ear, eyes, neck joints, and skin receptors report position against gravity, and posture is the answer the nervous system computes from that report. This is input quality and prediction working together, and it is why the model treats proprioception and the vestibular system as instruments rather than as sensations. Pettibon’s own 2005 review reached the same place from the other side when it concluded that misalignment is adaptive rather than random.

Warming the tissue changes what the same force means

The six minute window is the model’s time course dimension in operational form. An identical thrust delivered into a guarded spine and into a warmed spine produces two different events, because the tissue state determines what the input registers as. The model’s position that specificity is correspondence rather than force is exactly the reasoning behind Pettibon’s insistence that warm-ups precede every adjustment and that the toggle must outrun the muscle’s reflex.

Weighting is an input that makes the system correct itself

A two pound weight on the forehead cannot move a spine mechanically. It works by changing what the righting reflexes read, and the correction is then performed by the patient’s own muscles over ninety days. The model reads that as the cleanest available demonstration of distributed self-regulation: the doctor supplies an input, and the organization does the work. Posture is not a shape being pushed into place. It is the visible output of a control system, and the weight is a message to the controller.

What the Unified Model of Tone predicts about Pettibon weighting

The Unified Model of Tone predicts a bidirectional result from head weighting, and this is measurable. Take a group carrying both hypolordotic and hyperlordotic cervical curves and load every head. The model predicts convergence toward each person’s own midpoint rather than movement of the whole group one way. It predicts that the standard deviation of curve measurements narrows across the sample. A force applied to shape would shift everyone the same way. An input applied to regulation would not.

The model further predicts covariance. It treats vestibular, ocular, cervical, and autonomic measures as readings of one variable. So it predicts that postural reflex measures and heart rate variability move together across a ninety day weighting course, in the same subjects and on the same timeline. Independent variation of those measures would be evidence against the model. Tone held within its healthy range is health, because it preserves the capacity to adapt. Tone driven outside that range is what illness looks like from the inside.

The Pettibon System and Chiropractic BioPhysics share a root and split on method

Chiropractic BioPhysics grew directly out of Pettibon teaching. Donald D. Harrison taught the Pettibon seminars in Portland from 1977 to 1979, and in December 1980 he, Deanne Harrison, and Daniel Murphy named the new technique. Both methods film standing radiographs, both compare the result against a stated model of a normal spine, and both hold corrective loads for longer than an impulse lasts. The Harrison line and the Pettibon line are genuinely one family tree.

They part on who does the correcting. Chiropractic BioPhysics answers a measured displacement with its exact geometric reverse, doubled, applied through mirror image adjustments, exercise, and traction. The Pettibon System answers the same film by loading the head, shoulders, and hips so the righting reflexes generate the correction from the inside. One drives the body toward a target with an external vector, and the other gives the nervous system a reason to move itself there. Both are traction and rehabilitation methods, and the difference is where the corrective force originates.

Who teaches the Pettibon System now

The Pettibon System, Inc. operates from 2118 Jackson Highway in Chehalis, Washington, and maintains a provider directory open to licensed practitioners offering at least two Pettibon services. Instruction has historically run as a four course sequence: fundamentals of spine and posture rehabilitation, x-ray positioning and analysis and adjusting, soft tissue rehabilitation for clinic and home care, and case management. Certified instructors include Roger R. Elmer, a Pettibon System certified instructor and Fellow of the International Chiropractic Scoliosis Board. Mark W. Morningstar served as the Institute’s director of research and authored or co-authored eight PubMed-indexed papers between 2002 and 2007, including the 2005 reflex review with Pettibon. Continuing education credits are tracked through the Federation of Chiropractic Licensing Boards PACE program.

How this page relates to the rest of the library

Chiropractic BioPhysics is the other traction and rehabilitation method in this set, and it was named in December 1980 by the man who had taught Pettibon seminars for the previous two years. Atlas Orthogonal descends from the same Grostic seminars Pettibon attended in 1956, and shows what happens when that analysis stays at the top of the neck instead of spreading down it. Pierce-Stillwagon carries the name of the researcher Pettibon credits in his own historical account. The vestibular system and proprioception supply the two reflex channels a head weight is designed to address. Force transfer and posture reads alignment the same way from the athletic side, and movement explains why the wobble chair loads and unloads a disc rather than stretching it. Scoliosis is the condition most of the Pettibon literature addresses. Orthopedics holds the tissue mechanics of creep and viscoelastic deformation that the ninety day weighting schedule depends on. The Unified Model of Tone is the framework that reads all of it as one variable, and the full index of thirty three techniques places Pettibon among its neighbors.