Funded Research

Spinal Research facilitates chiropractic research that investigates the hypothesis that chiropractic care leads to better nervous system function, thereby enhancing health, quality of life and human performance. This research builds an evidence base in support of chiropractic, and grows certainty within the profession and community, resulting in chiropractic becoming a first choice in health care.

More detailed information on funded research is available for Foundation Members.  Learn more about membership here or Members can access factsheets here.

2017

The Impact of Chiropractic Adjustments on Brain Function and Integration

Do you have days when you reach for an object and miss, or seem to make a lot more typos than usual? A vertebral subluxation is an area in the spine of altered biomechanical and neurological function, which is treated by chiropractors. Vertebral subluxations alter the sensory feedback from the spine to the brain, and can affect your brain’s ability to blend information coming from other senses, affecting co-ordination and the ability to learn new movements. This project is measuring whether chiropractic care can improve eye-hand coordination, brain function and the learning and performance of complex new movements.

Chief Investigator: Professor Bernadette Murphy, University of Ontario Institute of Technology
Status: In Progress

The Accuracy, Reliability, and Validity of the Sacral Leg Check

Tests of sacral function are an integral component of many chiropractic techniques, however, individual tests that include sacroiliac joint motion have generally been found to have limited reliability and validity. The sacral leg check is routinely used in chiropractic practice but it’s clinical utility has not yet been adequately assessed. This project will evaluate the psychometric properties of the sacral leg check. This will include an assessment of the reliability, validity, and sensitivity to change of the test.  This should be of interest to chiropractors and educators who routinely use and teach the use of this test as a means of analysing subluxations in the sacroiliac region.

Chief Investigator: Dr Kelly Holt PhD, New Zealand College of Chiropractic
Status: In Progress

Reliability Of the Objective Synchronous Test as used in Abc™ – ‘ROOSTA’

Determining where to adjust is fundamental to the practice of chiropractic. Many of the methods commonly utilised in chiropractic practice have low reliability or conflicting results. There is no universally agreed upon ‘gold standard’ test for detecting subluxation, meaning that a validity study is not possible. However, the agreement between different chiropractors testing the same person can be measured statistically. The objective synchronous test is the primary procedure used by chiropractors trained in Advanced BioStructural Correction™ to determine where to adjust. This study aims to evaluate both the inter-rater and intra-rater reliability of this test. This research is important because the reliable detection of subluxation is fundamental to the clinical practice of chiropractic.

Chief Investigator: Dr Beau Woods MPH, Torrens University Australia and Dr Kelly Holt PhD, New Zealand College of Chiropractic, Dr Melinda Stanners PhD, Torrens University Australia
Status: In Progress

2015

The Effect of Cervical Spine Adjustment on Elderly Patient’s Grip Strength

The elderly suffer from reduced health-related quality of life and increased mortality from all causes in association with reduced grip strength. In addition, a recent study, wherin chiropractic neck adjustments increased judo athletes’ grip strength, recommended further similar studies, to evaluate performance enhancing effects of chiropractic adjustments, amongst other populations. The present preliminary study aims to determine whether chiropractic adjustments improve neck movement and grip strength in elderly patients. This investigation is important because the results will contrbute to the knowledge base regarding the effects of chiropractic adjustments and may open new pathways to explore the scientific basis of chiropractic theory.

Chief Investigator: Dr Adrian Wenban, Barcelona College of Chiropractic
Status: In Progress

Are pelvis-thorax coordination patterns altered following high-velocity low-amplitude spinal adjustment?

The therapeutic mechanism of spinal adjustment (SA) for low back pain patients remains elusive. One promising mechanism is the potential for SA to influence the different biomechanics and neuromuscular control of spine movement in low back pain patients. Our goal is to investigate the effect of SA on neuromuscular control of coordination patterns between the pelvis and thorax in low back pain patients. These data would provide clinicians and researchers with evidence for the mechanistic foundation of SA, and may also provide an objective outcome for clinical prediction rules to identify patients who are likely to improve with SA.

Chief Investigator: Dr Samuel Howarth, Canadian Memorial Chiropractic College and Dr Bernadette Murphy, University of Ontario Institute of Technology
Status: In Progress

2014

Epigenetic Regulation of Neuronal Differentiation by HVLA and LVVA Forces

Spinal manipulative treatment (SMT) is the primary clinical approach in chiropractic care. The cellular and molecular mechanisms responsible for SMT remain elusive. It is well know that SMT influences neurophysiological activities. However, a question remains: How can very short transient changes of cellular electricity impact patients’ long-term health? We propose to address this issue by examining whether manipulate forces impact neurons at cellular and molecular levels, particular in epigenetic regulation of neuronal differentiation – a potential mechanism in neuroplasticity. This research project should yield important insights in understanding the long-term benefits of chiropractic care.

Chief Investigator: Liang Zhang, Palmer College of Chiropractic
Status: In Progress

Developing an Animal Model of the Upper Cervical Subluxation

Subluxation of the upper cervical vertebrae is regarded among chiropractors as an important cause of disease and disability. However, currently there is no animal model of the upper cervical subluxation, and so it is difficult for researchers to study the underlying mechanisms and the clinical consequences of this lesion. This research will develop a model of the upper cervical subluxation, and test whether this model compromises spinal cord function and the function of visceral organs, as many chiropractors postulate. This model will permit researchers to address important questions about the consequences and treatments of upper cervical subluxation.

Chief Investigator: Dr Brian Budgell, Canadian Memorial Chiropractic College
Status: In Progress

Chiropractic Care and the Control of Eye Movement in Children with Attention Deficit hyperactivity disorder: A pilot study

Attention deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder that is associated with significant alterations in brain development and function.(1) One of these alterations in brain function involves a breakdown in the control of eye movement which can be responsible for the reading impairments that are often seen in children with ADHD.(2) It is possible that chiropractic care may enhance control of eye movements in children with ADHD. To study this potential relationship we will perform a crossover design pilot study that will investigate the effects of chiropractic care on the control of eye movement in 15 children with ADHD.

Chief Investigator: Dr Alice Cade, New Zealand College of Chiropractic
Status: Complete

2013

Chiropractic, Sensorimotor Integration and Function

Research has shown that chiropractic adjustments can improve reaction time, improve the timing of when postural muscles switch on, and improve the ability to perform tasks requiring co-ordination. The part of the brain which could be involved with these effects is the cerebellum, receiving information from the joints and muscles and communicating with all the other regions of the brain. This means that if there is a problem with the neck, it may not only cause neck pain, but it could actually affect the timing and co-ordination of movement and performing skills, as a result of the neck joints and muscles sending distorted feedback to the cerebellum. Thus, the cerebellum cannot perform optimally in its role in blending information from the brain and body. This project will further investigate how the cerebellum functions and how chiropractic adjustments affect the way that the cerebellum processes input from the joints and muscles from the hand and forearm. This project also plans to compare changes in the function of the cerebellum to the way that people perform tasks with their upper limbs following chiropractic adjustments. Tasks such as throwing, learning of new skills that challenge timing and use the hand muscles, and repositioning a subject`s upper limb in space.

This research has the potential to be making a fundamental contribution to our understanding of the role and mechanism behind spinal  adjustments. This will also help scientists to understand more about the way that the cerebellum functions when incoming sensory input is altered by spinal dysfunction. This work could have very important implications, perhaps suggesting that chiropractic care may be able to play a role  beyond treating pain, and in fact possibly benefiting everyone.

Chief Investigator: Professor Bernadette Murphy, University of Ontario Institute of Technology
Status: Complete

Neck PainBiomarkers & Chiropractic Outcomes

Neck pain has been estimated to occur in as many as 4 out of 5 individuals. For many, symptoms do not resolve. Healthcare and societal costs (work absenteeism, reduced productivity) associated with chronic neck pain are high and predicted to rise. Despite the common and successful use of chiropractic in patients with neck pain and some evidence for its effectiveness, the biological mechanisms by which chiropractic care reduces pain are less well understood.

Preliminary evidence indicates that the brain appears and functions differently when pain is present. In this project, we will investigate the effects of chronic neck pain on individuals, and the effects of chiropractic care and management on abnormal spinal function associated with chronic neck pain. We will determine whether we can identify clinical circumstances (from brain imaging and three-dimensional movement analysis) that distinguish patients with chronic neck pain from healthy individuals. This will identify specific physical signs (biomarkers) that clinicians can use to guide their care of patients with neck pain. We will also test whether a specific chiropractic procedure is effective in reducing chronic neck pain, and whether it changes the identified biomarkers, thus possibly providing evidence for their use in clinical practice to evaluate the effectiveness of care.

The results of this project could provide preliminary biological evidence for the potentially painreducing effects of a chiropractic procedure. This will provide clinicians with knowledge to improve the effectiveness of their care, impacting on the economic costs of spine problems, which are second only to heart disease and stroke in terms of healthcare expenditure.

Chief Investigator: Dr Suzanne Snodgrass, The University of Newcastle
Status: In Progress

The Effects of a Single Session of Chiropractic Care on Brain Source Connectivity

Over the past decade there has been growing evidence to suggest that chiropractic care influences brain function. The researchers that have done this work have used sophisticated brain research methods such as measuring brain waves using electroencephalography (EEG). These studies have shown that adjusting subluxations in the spine alters function in various brain structures. However, the evidence for the involvement of these brain structures is indirect. Although EEG measures brain activity very accurately time-wise, it has poor spatial resolution, which means it’s hard to tell exactly where in the brain the activity occurs.

Recently efforts have been made to improve the spatial resolution of EEG using a new EEG technique, known as multichannel matching pursuit technique. With this technique it is possible to determine with greater clarity where in the brain activity occurs. A group of chiropractic researchers in New Zealand and Canada are pairing up with a group from Denmark and intend to use this new technique to explore which structures in the brain are talking to each other prior to, and after, chiropractic adjustments.

The researchers believe that they will be able to identify differences in the way the brains of a group of 15 subluxated individuals, who are developing spinal symptoms, function compared with a group of 15 healthy people with no history of symptoms. They also believe that a single session of chiropractic care in the subluxated group will change the way parts of the brain are talking to each other. The researchers aim to reveal the brain areas involved in subclinical pain processing, then study the communication between these brain areas and how the communication changes following a single session of spinal adjustments.

By completing this study the researchers hope to gain a much better understanding about how vertebral subluxations and adjustments affect nervous system function.

Chief Investigator: Research Fellow Imran Khan Niazi, New Zealand College of Chiropractic
Status: Complete

2012

Muscle Thixotropy, Subluxation and Clumsiness

This project investigates the impact of the subluxation on joint position sense and movement. Chiropractors and their patients often report improvements in balance and coordination after having chiropractic care. In physiological terms, this may be defined as a decrease in the ability to accurately perceive where the limb is in space and how it is moving. This project plans to examine the plausibility that such improvements may be attributable to removal of the chiropractic subluxation. DD Palmer, the founder of chiropractic, defined the chiropractic subluxation as “too little or
too much nerve energy”. We have translated this definition into physiological terms – subluxation is a mechanical derangement with a resultant disruption of appropriate / accurate sensory signals that are transmitted into the central nervous system. One consequence of this disruption that may be experienced by patients is clumsiness – a decrease in the ability to accurately perceive where the limb is in space and how it is moving.

We have developed a physiological model of subluxation that exploits the property of muscle thixotropy. This phenomenon is usually applied to fluids that become stiff and viscous at rest but more fluid when stirred. Muscle also exhibits thixotropic behaviour. When the muscle is at rest, the muscle becomes stiff; when the muscle moves, stiffness is reduced. By exploiting muscle thixotropy, we are able to alter neck muscle stiffness and therefore the output from the muscle spindles (the length detectors) of the neck in a predictable way, either increasing or decreasing the quantity of the sensory signals. By changing the quantity of sensory signals from the neck we can measure the effect of ‘too much or too little nerve energy’ on the accuracy of a person’s perception of where body segments are in space and in relation to each other. This project may provide evidence to support the proposal that chiropractic subluxation contributes to clumsiness.

Chief Investigator: Dr Barbara Polus, RMIT
Status: In Progress

Chiropractic Care and the Cortical Silent Period

Chiropractic patients frequently report feeling great after an adjustment and experience results such as getting more out of their body, and coping more effectively with the stresses of daily life. Yet the ‘why’ behind these results has remained a subject of debate. Groundbreaking results of a recent research study suggest these positive outcomes are due to changes in brain function.

Research conducted in partnership by Dr Heidi Haavik, a leading chiropractor and neurophysiology researcher at the New Zealand College of Chiropractic, and world-renowned neurophysiologist, Professor Kemal Türker, found that subjects’ ability to flex their lower limb muscles increased by over 70% following just one full spine chiropractic adjustment session.

The results also indicated that the adjustment session allowed for greater drive from the brain to the muscle and prevented the muscles becoming fatigued. This research, which is pending publication, suggests that chiropractic care changes the way the brain sends messages down the spinal cord and out to muscles. It also suggests that the nervous system is able to produce greater muscle contractions following an adjustment, which may mean muscles become stronger.

Perhaps the most interesting finding was that the results recorded from the research subjects occurred after just one session of chiropractic care, yet were similar to what has been shown to occur in the body after three weeks of strength training1.

This research was conducted at the New Zealand College of Chiropractic thanks to a recent grant partnership between the Australian Spinal Research Foundation, The New Zealand Hamblin Trust and the New Zealand College of Chiropractic. Importantly, it will contribute to building the base of scientific evidence for what has long been understood from anecdotal reports; that chiropractic adjustments can result in greater energy, strength, better brain control, and less fatigue. This research demonstrates the ongoing benefits that flow directly from the Chiropractic Research Partnership, an initiative of Australian Spinal Research Foundation.

1 Vila-Chã, C., Falla, D., Correia, M. V., & Farina, D. (2012). Changes in H reflex and V wave following short-term endurance and strength training. Journal of Applied Physiology, 112(1), 54-63. doi:10.1152/ japplphysiol.00802.2011

Chief Investigator: Dr Heidi Haavik / Professor Kemal Türker, New Zealand College of Chiropractic
Status: Complete

2011

Chiropractic Adjustment and Cervicogenic Dizziness

Dizziness is a common problem that can lead to disability and impact on quality of life. In some cases of dizziness the cause can be attributed to pathology or dysfunction of upper cervical vertebral segments. This form of cervicogenic dizziness is characterized by symptoms of imbalance or spinning associated with neck pain, stiffness or headache.

One of the factors resulting in cervicogenic dizziness may be the mechanical compression of the vertebral artery. Reduced blood flow in one or both of the vertebral arteries may result from mechanical compression, tension, dissection or stenosis. This mechanical compromise of one or both of the vertebral arteries may be caused by poor head and neck posture and mal-alignment of the upper cervical spine, thus leading to cervicogenic dizziness. As such, adjusting the cervical spine to correct the mal-alignment could potentially improve vertebral artery blood flow and
affect dizziness.

The primary aim of this study is to investigate the potential role of reduced vertebral artery blood flow in the pathophysiology of cervicogenic dizziness. This study will also secondarily explore the potential influence of a course of upper cervical spine chiropractic adjustments on vertebral artery blood flow volume.

To date no studies have investigated the possible role of vertebral artery blood flow characteristics in the pathophysiology of cervicogenic dizziness or the potential beneficial effects of chiropractic upper cervical spine adjustment on the vertebral artery blood flow in patients with cervicogenic dizziness. Presently, there is some evidence to advocate the use of spinal adjustment or other manual therapy techniques for cervicogenic dizziness.
However, the effect of upper cervical spine chiropractic adjustment on the vertebral artery blood flow is still largely unknown.

This will be the first study to investigate a possible link between the changes in vertebral artery blood flow volume and severity of cervicogenic dizziness and the potential for upper cervical adjustment to provide a beneficial effect on vertebral artery blood flow volume in people with  cervicogenic dizziness. This project will expand the current knowledge of the pathophysiology and mechanisms underlying cervicogenic dizziness and improve our understanding on the effect of upper cervical chiropractic adjustment on the vertebral artery blood flow.

With dizziness being such a common clinical problem, this study has the potential to greatly affect clinical success and clinical outcomes from chiropractic care.

Chief Investigator: Dr Gary Shum, University of Plymouth
Status: Complete

Neuropathy Suppression by Spinal Manipulation

Chronic inflammation has vast consequences, possibly leading to life-threatening conditions, such as atherosclerosis and diabetes. This research investigates the relationship of the subluxation, neuropathy and IVF inflammation as well as the possibility that inflammation and its potential fatal consequences could be forestalled or even prevented by adjustments.

Lumbar intervertebral foramen inflammation plays a critical role in the pathogenesis of low back pain. This process can produce injury or disease to the structures and tissues within and / or adjacent to the IVF. These researchers will measure markers of inflammation and neuropathic pain, before and after adjusting.

This research will investigate a model that may demonstrate the possible fatal, long-term consequences of spinal subluxations as well as the effects of spinal adjustments on such conditions. Such findings have the potential to significantly advance the relevance and understanding of chiropractic care.

Chief Investigator: Professor Xue-Jun Song, MD, PhD, Ronald L.Rupert, MS, DC, Su Liu, PhD, Zhijiang Huang,
PhD, Yankai Zhang, PhD, Parker University Research Institute
Status: Complete

2010

The effect of Chiropractic Care on Synchronised Pelvic Floor Muscle Contraction

Many chiropractors notice that women under their care seem to have easier labours with less complications, fewer issues with incontinence and better core stability.

Pelvic floor muscle function is incredibly important for many reasons. Having coordinated, synchronous muscle function is important in labour (particularly in the pushing stage) in maintaining continence and in maintaining core stability along with activation of the abdominal muscles.

This study will investigate whether adjusting lumbopelvic vertebral subluxations changes pelvic muscle function. The study is designed in three stages. Study 1, which this grant relates to, aims to develop and test a new multi-sensor intravaginal surface electrode probe and test the validity and reliability of the probe. If the device is shown to be valid and reliable Study 2 will test the synchronicity of the pelvic muscle contractions of 90 women. Women who show asynchronous activity will be recruited for Study 3 where the investigators will test immediate pre and post adjustment measurements of pelvic muscle activity.

Chief Investigators: Dr Heidi Haavik /Dr Stanley Flavel, New Zealand College of Chiropractic
Status: Complete

Randomised Controlled Trial of the Effects of Sixteen Weeks of Chiropractic Care on Objective Markers of Sensorimotor Function in Older People

One of the biggest predictors of a loss of quality of life in older people is a fall. A fall in an older person is associated with large increases in their risk of morbidity and mortality. In people over the age of 65 80% of injury related hospital admissions are caused by falls and they are the leading cause of injury related death.

The research literature shows that falls often happen in association with a decline in nervous system function with ageing. What sort of difference could chiropractic make here? Could we deliver on our promise to “add years to your life and life to your years?” Some of the statistics relating to falls are:

  • In New Zealand and Australia 30% of older Australians have a fall each year. This is even greater in other parts of the world where rates are as high as 40%.
  • Every second fall causes an injury.
  • Serious injuries occur in around 30% of falls.
  • 5-10% of falls cause a fracture.
  • Costs of falls in the US estimated to be $32 billion by 2020.
  • The proportion of the population over 65 is expected to double in the next 50 years.

There is also a huge social cost of falls in terms of loss of independence, depression and overall quality of life.Many clinical studies are criticised by field practitioners for having too short a period of care to expect to see much physiological change. This study utilises 16 weeks of chiropractic care. It is also based on assessment and correction of vertebral subluxation. The outcome measures for this study are objective markers of sensorimotor function. In other words, they are established measures of how well the brain and nervous system process information.

Some of the outcome measures are:

  • Choice stepping reaction time. A testing approach that uses special platform that tests the ability to control foot placement. It has been previously shown to predict fallers vs non-fallers.
  • Joint Position sense of the ankle.
  • Postural stability using computerised posturography.
  • SF 36

Chief Investigators: Dr Kelly Holt/Dr Heidi Haavik /Associate Professor Bernadette Murphy/Dr C Raina Elley, New Zealand College of Chiropractic
Status: Complete

The Effect of Chiropractic Care on Cerebellar Function

The overall objective of the proposed project is to investigate the role of the cerebellum in sensorimotor integration (SMI) following spinal adjustments in human participants who have pre-existing spinal dysfunction in the form of vertebral subluxations. The general hypothesis is that the cerebellum is the central integrator of proprioceptive input and that when the balance of afferent input is normalized by spinal adjustments, it helps to normalize sensorimotor integration and motor control via the cerebellar interactions with the basal ganglia, cortex and periphery.

Understanding the mechanisms of the changes in SMI will help clinicians understand who is most likely to benefit from chiropractic care, help identify patients with disordered SMI who may need adjustments to be combined with other approaches or who may need a longer course of care, potentially providing a rationale for treating people with recurrent neck and back pain as a way of normalizing sensorimotor integration to break the cycle of recurrence. This research has the potential to shift away from the “pain treatment” model into a “normalization of SMI” model to
prevent the development of chronic pain, to enhance function, to decrease the risk of injury in occupational, domestic and recreational settings.

Chief Investigators: Professor Bernadette Murphy and Dr Heidi Haavik, University of Ontario Institute of Technology
Status: Complete

Effects of Spinal Manipulation on Thalamic Mechanical Response Threshold

For almost 120 years chiropractic has been based on the idea that chiropractic adjustments help people live healthier, happier more active lives by removing interference to the nervous system. Chiropractors have also placed a lot of emphasis on specificity – the idea that the line of drive of the adjustment and the amount of preload applied in setting up for the adjustment are incredibly important aspects of the art of the adjustment. This study aims to add to the understanding of these two ideas by measuring the effect of chiropractic adjustments to adjustments using different preload, force and line of drive.

Most recent theories on the mechanism of chiropractic adjustments emphasise the central role of the thalamus. Its function includes relaying sensation, spatial sense, and motor signals to the cerebral cortex, along with the regulation of consciousness, sleep, and alertness. Since the thalamus serves as an integration and relay site for neural messages sent from the rest of the body, it becomes an excellent location to study the sensory effects of the spinal adjustment.

This study will use electrophysiological recording techniques to record the response from neurons in the thalamus before and after a spinal adjustment has been given to a rat vertebra in the lower back.

Chief Investigator: Dr William Reed,Palmer College of Chiropractic
Status: Complete

2009

Somato-Sympathetic Responses to Chiropractic Adjustments in a Model of Cervical Disc Degeneration

Chiropractic theories advocate that physiologic effects of chiropractic adjustments have an effect upon the sympathetic nervous system (SNS). These theories are used to explain the mechanisms to justify the clinical benefits observed in patients with Type O disorders receiving chiropractic care.

Because a validated research model of vertebral subluxation has yet to be defined, The objective of this study is to examine the effects of chiropractic adjustments on somato-sympathetic responses in an ovine model of cervical disc degeneration.

Not only is cervical disc degeneration a common spinal condition affecting human kind, it also provides a unique opportunity to study a subgroup of vertebral subluxation, characterized by altered mechanical loading with biochemical consequences.

Chief Investigators: Christopher Colloca, Research Scientist Department of Kinesiology Arizona State University Robert J. Moore Head, Adelaide Centre for Spinal Research, Adelaide, Australia Robert Gunzburg, Dept of Orthopaedic Surgery, Eeuwfeestkliniek Hospital, Antwerp, Belgium
Status: Complete

Do Chiropractic Vertebral Adjustments Modulate Sympathetic Nerve Activity in Humans?

Chiropractors use a variety of clinical interventions to care for their patients spines in an effort to improve and maintain good health. Some of these interventions, known as spinal adjustments are done by hand and some are done with the assistance of specially designed hand held instruments. There are clinical case reports that suggest that these spinal adjustments not only assist people with back and neck pain but that they may influence other conditions not normally associated with dysfunction in the spine. One hypothesis proposed by chiropractors is that their spinal adjustments, sometimes referred to as spinal manipulative therapy, influences the sympathetic nervous system which is a part of the nervous system involved in the reflex control of blood pressure. However, there is only limited indirect evidence to support this hypothesis.

The aim of this study is to determine whether chiropractic spinal adjustments significantly alter sympathetic nerve activity in humans. To do this, functions regulated by the sympathetic nervous system including blood pressure, heart rate, breathing, skin blood flow and sweating will be  measured in young adult volunteers eligible for chiropractic adjustments. Uniquely this study will simultaneously record from sympathetic nerves in these same individuals before, during and after chiropractic adjustments applied to the vertebral column and the upper limb. We will examine  and compare the effects of manual and instrument assisted chiropractic adjustments.

Importantly, and for the first time, this study will provide information about the influence of chiropractic adjustments on sympathetic nerve activity recorded directly from sympathetic nerves in humans. We will also determine whether two different types of chiropractic adjustments influence sympathetic nerves in the same way and whether the location of the application of a chiropractic adjustment produces different effects on sympathetic nerves. The findings of this study will significantly inform the clinical practice of chiropractic.

Chief Investigator: Assoc Prof Philip Bolton, University of Newcastle
Status: In Progress

2008

Chiropractic “Subluxation” Model for Human Research

The most common reason patients visit chiropractors is for spinal pain and injury including injuries and pain to the neck. Whiplash is an example of a significant injury affecting neck structures. The consequences of this injury include disturbances in balance and alterations in the perception of where body segments are located in space. Neck pain, without injury, is also associated with such disturbances. Chiropractors adjust spinal joints for the treatment of neck pain and this therapy is directed to resolution of the “subluxation”.

The literature reports that spinal adjustments are effective in the management of neck pain, therefore, the implication is that the chiropractic subluxation contributes to the symptom complexes associated with neck pain and that the adjustment contributes to resolving the symptom complexs associated with these conditions. However, the chiropractic subluxation is poorly defined in physiological terms. One definition of subluxation in physiological terms is “a mechanical derangement of a spinal joint which alters the quality and quantity of sensory signals to the central nervous system (CNS)”. Methods used to artificially increase the level of non-painful sensory signals from neck muscles into the CNS (such as vibration of neck muscles) is known to result in balance and movement disturbances. However this method indiscriminately activates many sensory receptors. This research project will test the hypothesis that a systematic change in dorsal neck muscle proprioceptive inputs to the CNS results in a predictable change in neck-body position sense. Such a change provides evidence that systematic alterations in proprioceptive signals to the CNS contributes to one of the symptoms associated with common musculoskeletal conditions that are both seen and successfully managed by chiropractors.

Chief Investigator:Dr Barbara Polus, RMIT
Status: In Progress

The Effect of Chiropractic Care on Central Somatosensory Processing and Sensorimotor Integration Utilising the Dual Peripheral Nerve Stimulation Somatonsensory Evoked Potential Technique

It is hypothesised that vertebral subluxations result in altered afferent input to the CNS, which in turn may lead to alterations in somatosensory processing, sensorimotor integration, and motor control. Thus, the vertebral subluxation may lead to (or reflect existing) maladaptive central plastic changes that can cause ongoing pain and loss of functional ability.

This research looks at the effects of a period of chiropractic care on somatosensory processing and sensorimotor integration at multiple levels of the CNS, using a technique that measures immediate neural plastic changes.

This study has the potential to provide objective neurophysiological evidence that chiropractic care can lead to long term central plastic changes in sensorimotor integration. The results may help to clarify the mechanisms for the longlasting improvements demonstrated previously following chiropractic care.

Chief Investigator: Dr Heidi Taylor (Haavik), New Zealand College of Chiropractic
Status: Complete