RESEARCH LIBRARY
Natural healthcare backed by science.
Glossary
The current evidence based term for subluxation is 'a central segmental motor control problem’. The definition is a ‘central segmental motor control problem causing maladaptive neuroplastic changes that affects the overall health and well-being of an individual’.
Neurological
This review article reviewed and summarised all the research to date on chiropractic subluxation’s (vertebral column joint dysfunction). This review discusses the research that indicates that a subluxation occurs when physical injury, pain, inflammation and acute or chronic physical or mental stress causes spinal segments to not move properly. This abnormal movement (too much or too little) interferes with sensory input to the brain from the deep muscles attached to the spine. This then alters how the brain processes internal and external sensory information, which ultimately leads to poor motor control of the spine. Over time, this can lead to ongoing changes to the brain and nervous system that can have negative effects on the body.
This review also provides a thorough summary of the literature that shows how chiropractic adjustments influence the brain’s control of the muscles.
This is the most extensive current review that synthesises the literature on how chiropractic subluxations affect the body and that spinal adjustments can impact muscle control in a variety of ways.
Haavik, H., Kumari, N., Holt, K., Niazi, I. K., Amjad, I., Pujari, A. N., ... & Murphy, B. (2021). The contemporary model of vertebral column joint dysfunction and impact of high-velocity, low-amplitude controlled vertebral thrusts on neuromuscular function. European Journal of Applied Physiology, 1-46.
A number of research studies had found that chiropractic adjustments change how the brain processes and integrates sensory information and then creates movement, something called sensorimotor integration. This study sought to investigate which areas of the brain were involved in these changes to sensorimotor integration.
Nineteen participants were included in the study. Researchers used special equipment to measure electrical activity in the brain to compare and identify which areas of the brain showed changes following chiropractic spinal manipulation and following a sham control intervention.
The findings of this study demonstrated that following chiropractic spinal manipulation a decrease in the N30 amplitude was seen, whilst in the control group no changes were noted. This difference was statistically significant. The underlying brain source of these changes was localised to the prefrontal cortex.
This was the first study of its kind to identify the brain source of sensorimotor changes following chiropractic adjustments. The identification of the prefrontal cortex as the primary source of brain changes has been an important discovery in understanding the neurological effects of chiropractic care. The prefrontal cortex plays an important role in sensorimotor integration and is responsible for executive functions, which is the control and co-ordination of numerous processes required in planning and goal-directed tasks in response to the environment around us. The prefrontal cortex is also involved in pain modulation, the immune response and autonomic nervous system functions. This finding has helped researchers and chiropractors in understanding why patients report numerous benefits to chiropractic care, that exceed pain reduction alone.
Lelic, D., Niazi, I. K., Holt, K., Jochumsen, M., Dremstrup, K., Yielder, P., ... & Haavik, H. (2016). Manipulation of dysfunctional spinal joints affects sensorimotor integration in the prefrontal cortex: a brain source localization study. Neural plasticity, 2016.
This study was conducted as a follow up to previous research that had investigated the short-term effects of chiropractic adjustments on neuromotor control in chronic stroke survivors. We wanted to understand longer term effects of chiropractic care in chronic stroke survivors and whether the changes in neurological function translated to clinical changes of function. So, this study investigated whether the addition of chiropractic care to 4 weeks of physical therapy care for chronic stroke survivors improved their ability to use their weak limbs.
In this study, researchers randomly allocated 63 chronic stroke participants into two groups- one group received chiropractic adjustments plus normal physical therapy, the other group received the same physical therapy and a sham control intervention. To assess for improvements in motor function we used a measurement called the Fugl-Meyer assessment, which is a highly reliable and valid scale that measures movement ability, coordination, speed and control after stroke. This was assessed at baseline, after the 4 weeks of the intervention and again at 8 weeks to see if the effects remained four weeks after the four-week intervention period had finished.
The results showed that at 4 weeks both groups improved, but the group that received chiropractic care plus physical therapy had significantly more improvement in the function of their affected limbs than the group that was not adjusted. What this means is that chiropractic care, plus usual physical therapy, appears to have greater benefit to motor recovery in stroke survivors than physical therapy alone.
This ground-breaking research allows a greater understanding of the effects of chiropractic adjustments on brain function and how chiropractic care could be utilised in the neurorehabilitation of stroke survivors to improve their functional outcomes.
Holt, K., Niazi, I. K., Amjad, I., Kumari, N., Rashid, U., Duehr, J., ... & Haavik, H. (2021). The Effects of 4 Weeks of Chiropractic Spinal Adjustments on Motor Function in People with Stroke: A Randomized Controlled Trial. Brain Sciences, 11(6), 676.
This review papers discusses what the research shows about the effects of chiropractic care on the central nervous system. A model is proposed that demonstrates how a vertebral subluxation can disrupt the sensory information that is sent from the spine to the brain. This has a flow on affect and alters how the brain processes and integrates all the sensory information that it receives from our body and the world around us. Changes in this processing and integration can ultimately leading to changes in how our brain can control and co-ordinate our muscles and can contribute to pain and dysfunction in the body. The effects of a chiropractic adjustment and how it can reset this pathway is also outlined.
Taylor, H. H., Holt, K., & Murphy, B. (2010). Exploring the neuromodulatory effects of the vertebral subluxation and chiropractic care. Chiropractic Journal of Australia, 40(1), 37-44.
This research investigated the effects of chiropractic spinal manipulation on the central nervous system and in particular changes to sensorimotor integration and motor control.
This body of work has helped chiropractors, researchers and other health professionals understand how an initial episode of back or neck pain can lead to ongoing changes of sensory input from the spine and lead to negative changes in the brain and altered sensorimotor integration and subsequent motor control.
Chronic musculoskeletal pain affects millions of people in the world, has significant financial and healthcare burdens and contributes to further long-term health problems such as depression and cardiovascular diseases. The research studies discussed in this review give an understanding and explanation as to how chiropractic spinal manipulation could change central processing of sensory information, improve function and reduce chronicity and re-occurrence of musculoskeletal pain.
Haavik, H., & Murphy, B. (2012). The role of spinal manipulation in addressing disordered sensorimotor integration and altered motor control. Journal of Electromyography and Kinesiology, 22(5), 768-776.
This study investigated whether chiropractic adjustments to the neck improved the person’s ability to accurately sense where their arm was positioned in space. Participants for this study had something called ‘subclinical neck pain’ which is when an individual has a history of recurrent neck pain that they have not sought treatment for, but were pain-free on the day they participated in the study. This allows researchers to look at the effects of chiropractic adjustments on the nervous system without the changes that can occur to the brain and body from being in pain.
In this study participants had their eyes closed and their elbow joint put into a set position. They then received a chiropractic adjustment to a dysfunctional segment of their neck (intervention group) or a 5 minute rest period (control group) and then were required to re-position their elbow to the same point as previous with their eyes closed. This measures a function of the body called joint position sense, which is something that the brain controls through accurately sensing where our body is in space and controlling our movement.
The participants that received the chiropractic adjustment had better joint position sense than the control group that did not get adjusted. This study demonstrates that chiropractic adjustments may improve the sensory information coming from the neck to the brain and help the brain to more accurately perceive what is happening in our body and where our body is in space.
Haavik, H., & Murphy, B. (2011). Subclinical neck pain and the effects of cervical manipulation on elbow joint position sense. Journal of manipulative and physiological therapeutics, 34(2), 88-97.
This study investigated changes to the function of the cerebellum, the part of the brain that is largely responsible for balance and fine motor control, following chiropractic spinal adjustments. In this study participants had something called ‘subclinical neck pain’ which is when an individual has a history of recurrent neck pain that they have not sought treatment for, but were pain-free on the day they participated in the study. This allows researchers to look at the effects of chiropractic adjustments on the nervous system without the changes that can occur to the brain and body from being in pain.
The researchers measured brain function using special equipment and measured the connection between the cerebellum and the motor cortex (the part of the brain that controls movement). They then had participants complete a motor learning task where they were required to learn and perform a set typing sequence and they then received chiropractic adjustments to areas of spinal dysfunction. Researchers then re-measured the same brain function as before to see if the cerebellum function changed, they compared these results to a second group that did the same motor learning task but did not receive chiropractic adjustments.
They found that the group that received chiropractic adjustments showed changes to their cerebellum function and the control group did not.
Daligadu, J., Haavik, H., Yielder, P. C., Baarbe, J., & Murphy, B. (2013). Alterations in cortical and cerebellar motor processing in subclinical neck pain patients following spinal manipulation. Journal of manipulative and physiological therapeutics, 36(8), 527-537.
Children
Holm, L. V., Jarbøl, D. E., Christensen, H. W., Søndergaard, J., & Hestbæk, L. (2021). The effect of chiropractic care on infantile colic: Results from a single-blind randomised controlled trial. Chiropractic & Manual Therapies, 29(1), 1-11.
This review assessed the available research on adverse events related to manual therapy for infants and children. This covers manual therapy provided by chiropractors, physios, osteopaths, cranial-sacral therapists and medical doctors. The reviewers found that serious adverse events associated with manual therapy in infants and children are rare. If they did occur it was usually due to an underlying medical condition. Chiropractic care for infants and children is very safe when done properly and with a thorough history taken.
Todd, A. J., Carroll, M. T., Robinson, A., & Mitchell, E. K. (2015). Adverse events due to chiropractic and other manual therapies for infants and children: a review of the literature. Journal of manipulative and physiological therapeutics, 38(9), 699-712.
SPORTS PERFORMANCE
In this research study premier league soccer players were recruited to assess the effects of spinal manipulation on kicking speed performance. Forty players were split into four different groups- one that received chiropractic adjustments to the lumbar spine only, one that received chiropractic adjustments to the pelvis only, one that received chiropractic adjustments to both the lumbar spine and pelvis and a final group that did not receive any chiropractic adjustments.
The players were assessed for kicking speed before and after the intervention (adjustments or control). The results of this study showed that kicking speed was increased in all three groups that received chiropractic adjustments, with the group that received both lumbar and pelvic adjustments having the greatest improvement.
This study had a small sample size and the groups were not randomly allocated so this study should be repeated to validate the findings.
Deutschmann, K. C., Jones, A. D., & Korporaal, C. M. (2015). A non-randomised experimental feasibility study into the immediate effect of three different spinal manipulative protocols on kicking speed performance in soccer players. Chiropractic & manual therapies, 23(1), 1-10.
This research article is a systematic review of the best available research evidence on the effects of spinal manipulation on sports performance. The researchers have identified 7 clinical trials on this topic, they have then synthesised and summarised their findings and also assessed the quality of the studies and the overall evidence.
They found that 4 out of the 7 included studies demonstrated improvement in sports performance following spinal manipulation. Overall, more research is needed on this topic but the results are promising.
Botelho, M. B., Alvarenga, B. A., Molina, N., Ribas, M., & Baptista, A. F. (2017). Spinal manipulative therapy and sports performance enhancement: a systematic review. Journal of manipulative and physiological therapeutics, 40(7), 535-543.
This study compared the effects of chiropractic spinal manipulation plus stretching to stretching alone in golf players. They assessed the outcomes of 43 golf players based on full-swing performance. One group received chiropractic care plus a standard stretching programme, and the other group received the stretching programme only. Each participants received the intervention once per week for 4 weeks.
The researchers found that the group that recieved the chiropractic care plus the stretching had an improvement in swing performance after the adjustments each week. No improvement was seen in the stretching group alone. When comparing the two groups the chiropractic group had a significant improvement over stretching alone.
There is a growing body of research that suggests that chiropractic care could be beneficial for sports performance enhancement.
Costa, S. M., Chibana, Y. E., Giavarotti, L., Compagnoni, D. S., Shiono, A. H., Satie, J., & Bracher, E. S. (2009). Effect of spinal manipulative therapy with stretching compared with stretching alone on full-swing performance of golf players: a randomized pilot trial. Journal of chiropractic medicine, 8(4), 165-170.
OLDER ADULTS
This survey was conducted over 12 years and included 1,057 people over 70 years old who sought help for a single episode of back pain. The researchers interviewed them every two years and looked at health differences between people receiving medical-only care or chiropractic care.
Their main outcomes were ‘activities of daily living’ (i.e. getting across a room, getting dressed, bathing or showering, eating, and getting in or out of bed); ‘instrumental activities of daily living’ (i.e. using a telephone, taking medication, handling money, shopping, and preparing meals); lower body function (i.e. climbing up and down one flight of stairs, walking several blocks, pushing or pulling heavy objects, and lifting or carrying 10 or more pounds) as well as self-rated health and progression of depressive symptoms. Interestingly, 11% less people receiving chiropractic care had a decline in ‘activities of daily living’ and ‘instrumental activities of daily living’. Lower body function decline also occurred in less people receiving chiropractic care (30% vs 38%). However, they did not find any difference in self-rated health and in worsening of depressive symptoms between the medical-only and chiropractic groups.
This study is interesting as it presents data from a large sample taken from ‘real-life’ settings in the community. Overall, those results suggest that chiropractic, even when primarily sought after to reduce the discomfort related to back pain, has a protective effect on the level of activities older adults are able to engaged in their everyday life. This means that chiropractic care is a valid modality that older adults can use to foster their quality of life and independence.
Weigel, P. A., Hockenberry, J., Bentler, S. E., & Wolinsky, F. D. (2014). The comparative effect of episodes of chiropractic and medical treatment on the health of older adults. Journal of manipulative and physiological therapeutics, 37(3), 143-154.
This study was conducted in New Zealand over 12 weeks and included 56 older adults (>65 years old). They were divided into a ‘control’ group (no intervention) and a ‘chiropractic’ group, which received regular chiropractic care, as deemed appropriate by the chiropractor they were seeing in the community. Since falls account for more than 80% of injury-related hospital admissions in people over 65 years, researchers were interested in factors related to fall risks. In particular they measured people’s postural stability, ankle ‘proprioception’ (i.e. the ability for the brain to know where the joints are in space to be able to provide controlled and adequate movement), and multi-sensory integration (i.e. the ability of the brain to manage efficiently multiple stimulus simultaneously, similar to what would happened if you walked upstairs while being on the phone and carrying an object for instance). They also measured health related quality of life.
Researchers examined participants at the start of the study, after 4 weeks and after 12 weeks. They found significant improvement in all of the neurological factors involved with fall risk described above. This suggests that chiropractic might have a role to play in ‘sharpening’ the brain’s ability to monitor the external environment, such as sound, and internal environment such as postural muscles control and perception of where ankles are in space. In addition, the chiropractic group reported improvement in the physical aspect of their quality of life.
Interestingly, most of the improvements were observed between 4 weeks and 12 weeks, which suggest that longer-term chiropractic care might be required to create meaningful changes in the way the brain is perceiving the environment.
Holt, K. R., Haavik, H., Lee, A. C. L., Murphy, B., & Elley, C. R. (2016). Effectiveness of chiropractic care to improve sensorimotor function associated with falls risk in older people: a randomized controlled trial. Journal of manipulative and physiological therapeutics, 39(4), 267-278.
This study involved 12,170 adults over 65 years old and assessed the changes in their abilities to perform activities of daily living (such as bathing, dressing and eating), lifting, stooping, walking as well as their self-rated health and their overall satisfaction with care. The authors compared adults using medical care only to chiropractic users. They found that over 1 year, chiropractic care significantly reduced the decline in the everyday activities described above, including the ability to walk, dress, bath and lift objects. The group that received chiropractic care was also overall more satisfied with their follow-up care, the information provided to them regarding their conditions and rated their health better than their medical-only care counterpart.
Overall, this study suggests that chiropractic care can help prevent the health decline commonly associated with ageing and that as part of a healthy lifestyle could help older adults remain active longer in the community.
Weigel, P. A., Hockenberry, J. M., & Wolinsky, F. D. (2014). Chiropractic use in the Medicare population: prevalence, patterns, and associations with 1-year changes in health and satisfaction with care. Journal of manipulative and physiological therapeutics, 37(8), 542-551.
NECK & BACK PAIN
Low back pain is one of the most common reasons that people seek chiropractic care. It is also one of the most common debilitating conditions in the world and one of the top reasons that people require time off work. Low back pain often becomes a chronic issue that keeps recurring. Sometimes people seek chiropractic care only at the time that they have low back pain for symptom management.
This study investigated whether maintenance care was more effective at reducing low back pain than only seeing a chiropractor when you have symptoms. Maintenance care is when you continue to see your chiropractor on a regular basis even when you are symptom free to help keep the body functioning at its best and prevent further episodes of low back pain. The results of this study showed that people who were under maintenance care had significantly fewer days when they experienced low back pain, compared to the group that only sought care when they had symptoms.
Eklund, A., Jensen, I., Lohela-Karlsson, M., Hagberg, J., Leboeuf-Yde, C., Kongsted, A., ... & Axén, I. (2018). The Nordic Maintenance Care program: Effectiveness of chiropractic maintenance care versus symptom-guided treatment for recurrent and persistent low back pain—A pragmatic randomized controlled trial. PloS one, 13(9), e0203029.
Low back pain is one of the leading causes of disability world-wide and a very common reason to seek medical care. Usual medical care for low back pain consists of pain relief medications such as Ibuprofens or opioid medications, steroid injections into the joints or spinal fusion surgery. However, these treatments come with some significant side effects and are contributing to an opioid crisis where too many people have become addicted and reliant on strong opioid pain medication.
This study compared the effects of chiropractic care plus standard medical care to medical care alone on low back pain and disability in members of the US military. The results showed that the addition of chiropractic care to usual medical care resulted in significant improvements in low back pain intensity, disability and satisfaction. They also reported a significant reduction in pain medication use in the group that received chiropractic care.
Goertz, C. M., Long, C. R., Vining, R. D., Pohlman, K. A., Walter, J., & Coulter, I. (2018). Effect of usual medical care plus chiropractic care vs usual medical care alone on pain and disability among US service members with low back pain: a comparative effectiveness clinical trial. JAMA network open, 1(1), e180105-e180105.
Read full article
This study is a systematic review of the best available research evidence on the effects of spinal manipulation and mobilisation for chronic non-specific neck pain. A systematic review is a large study which assesses the quality of all the research on a particular topic and a meta analyses combines the results of all the studies included. This large study concluded that there is low-moderate quality of evidence that spinal manipulation or mobilisation reduces pain and improves function for chronic non-specific neck pain. They pointed out that a combined approach of different treatments had the best outcomes but more studies need to be done. The research also suggests that spinal manipulation is a safe option.
Coulter, I. D., Crawford, C., Vernon, H., Hurwitz, E. L., Khorsan, R., Booth, M. S., & Herman, P. M. (2019). Manipulation and mobilization for treating chronic nonspecific neck pain: a systematic review and meta-analysis for an appropriateness panel. Pain physician, 22(2), E55.
This study is a systematic review of the the best available research evidence on the effects of spinal manipulation and mobilisation for low back and neck pain. A systematic review is a large study which assesses the quality and results of research on all the research on a particular topic. The researchers found that spinal manipulation is as effective or more effective than common pain relief medications, physical therapy strategies or general practitioner management for acute and chronic low back pain and neck pain. However, more research needs to be done in some areas.
Bronfort, G., Haas, M., Evans, R. L., & Bouter, L. M. (2004). Efficacy of spinal manipulation and mobilization for low back pain and neck pain: a systematic review and best evidence synthesis. The spine journal, 4(3), 335-356.
HEADACHES
This study compared the effects of spinal manipulation to a common medication used to treat chronic headaches called Amitriptyline. The researchers assessed the participants for changes in headache intensity, frequency, how much pain relief was used and overall functional health status. One group received chiropractic care for 6 weeks and the other group received the Amitriptyline medication for 6 weeks.
The results of this study found that both groups had an improvement in all four outcome measures. However, they re-assessed the participants 4 weeks after their 6 week treatment phase and found that the group that had chiropractic care continued to show improvements but the medication group had gone back to baseline and some had even gotten worse. This is an important finding because it highlights that chiropractic care affects the cause of the problem and so has more lasting changes, rather than just treating symptoms as many medications do.
Boline, P. D., Kassak, K., Bronfort, G., Nelson, C., & Anderson, A. V. (1995). Spinal manipulation vs. amitriptyline for the treatment of chronic tension-type headaches: a randomized clinical trial. Journal of manipulative and physiological therapeutics, 18(3), 148-154.
Read full article
Tuchin, P. J., Pollard, H., & Bonello, R. (2000). A randomized controlled trial of chiropractic spinal manipulative therapy for migraine. Journal of manipulative and physiological therapeutics, 23(2), 91-95.
“Medicine is the study of disease and what causes man to die. Chiropractic is the study of health and what causes man to live.”
B. J. Palmer