How does Chiropractic Work?

How does chiropractic work is a great question I am often asked in the clinic. The question is complex with a lot to unpack. However, now that we have addressed a lot of questions in other blog posts, we can now tackle “How does Chiropractic work?” We will be linking a lot of our previous posts to help answer this question to help keep this blog as concise as possible. If you haven’t read these previous blog posts, they are quite good you know!

We cannot explore the question How does Chiropractic work, without first explaining its history, for us to know where we are going, we must first understand where we started. The chiropractic profession has some deep-rooted philosophical concepts that we are likely to touch upon during this blog. As regular readers of my blogs will know, I enjoy discussing controversial topics found within chiropractic and other manual therapy professions. That being said, the chiropractic profession was founded in the late 1800’s by Daniel David Palmer, and therefore many of its philosophical concepts are rooted in 120+ years of Christianity and spiritualism¹. As a result, these concepts are very close to some practitioners’ hearts as some still subscribe to these philosophies and integrate them into their current practice. Therefore, I will do my best to not discuss these philosophical concepts in detail. As a scientist, the concepts discussed in this blog are strictly from recent scientific research and from a scientific perspective.

We have already discussed what the crack is when a chiropractor manipulates your spine, but what does spinal manipulation do? How does Chiropractic work?

Spinal Health and Dysfunction

A functional and healthy human spine has 24 movable vertebrae that stack up on top of one another forming a S-shaped column. We discussed the normal shape and curves of the spine in a previous blog post.

If there is only one thing that everyone takes from the blog post, is that the fundamental philosophy of chiropractic is all about spinal health and restoring normal spinal segmental motion and optimal function. This then implies that the spinal segments become dysfunctional and therefore require a treatment/intervention to restore normal function right?

There are several concepts and models of spinal dysfunction². These different models have many different terms that are used to describe the location of dysfunction between the spinal segments. These names include but are not limited to ‘manipulable or functional spinal lesion’, ‘vertebral spinal lesion’, ‘vertebral subluxation’, ‘Chiropractic subluxation’, ‘vertebral subluxation complex’, ‘biomechanical joint dysfunction’, and a ‘spinal fixation’ ^2–5. Spinal subluxation is the original term used to describe and diagnose this dysfunction. The term was first used by the founder of Chiropractic D. D. Palmer back in the late 1800’s who said that only chiropractors can detect and remove subluxations. As a result of Palmer’s old writing from 120+ years ago, subluxations has its roots in spiritualism like many medical terms from their day and therefore are seen by some to have demi-religious inferences. Spinal subluxations is a “dirty word” in the UK with the General Chiropractic Council (GCC) having relegated the term subluxation to the chiropractic history books⁶.

For the sake of this blog post and professional inclusivity, I will refer to spinal joint dysfunction as spinal lesions.

The spine can become dysfunctional and develop these spinal lesions through several means including:

• Prolonged poor posture.
• Postural disorders (e.g., scoliosis and kyphosis).
• Neurological disorders (e.g., Parkinson’s disease, cerebral palsy).
• Spinal trauma.
• Inflammatory disorders (e.g., Rheumatoid arthritis, axial spondylarthritis)
• Post-surgical complications (e.g., spinal fusion surgery).

When these spinal lesions develop, the spinal segments lose their mobility, gradually getting stiff, often resulting in pain. Other negative effects of spinal dysfunction include changes within the central nervous system and spinal muscles^2,7. These changes are described as maladaptive changes of the central nervous system, and result in rapid atrophy (loss of size and strength) of the surrounding spinal muscles, ^{8–10,11–16} neurological inhibition, muscle fibrosis (scar tissue), and fatty infiltration of the spinal muscles ^11,12. During the early (acute) stages of any injury, the same inflammatory changes occur that we have discussed in our previous blog post as well, adding to the severity of the pain experienced.

Fig. 1 demonstrates the negative feedback loop of spinal dysfunction and its subsequent neurological and physical (neurophysiological) changes, or maladaptive changes. When spinal joints become dysfunctional, maladaptive changes in the central nervous system begin, resulting to weakness of the surrounding muscles, and a loss of control of the joints movements. The loss of control causes the mechanoreceptors to send incorrect information to the brain, which results in abnormal processing of this information. This is called sensorimotor processing and it is where the mechanoreceptors feedback information regarding the location and position of every part of your body to the brain. When these spinal lesions occur, maladaptive changes begin to provide inaccurate information to the brain, which is then processed incorrectly and the brain sends the wrong information back to the spine/joint. Abnormal sensorimotor processing leads to further abnormal joint movements, leading to pain.

If treatment is not sought, the lack of muscular strength and control of the injured spinal joints leads to dysfunctional movement of the spinal segments and the development of chronic pain syndromes, including back and neck pain¹⁸.  The longer the injury is left before treatment is sought, the worse the muscle weakness, loss of control of the joints and therefore overall joint dysfunction gets.

Fig.1 Demonstrating the neurophysiological changes that occur as a result of spinal dysfunction leading to pain (adapted from Haavik & Murphy 17).                                                                                                                                                           

Hopefully, some of you reading this have just had a light bulb moment, as this answers the question of recurrent pain episodes when it comes to back and neck pain. There is a common cycle of back pain, where the patient injures their back, but the pain resolves itself and they feel better. Their recovery might have taken a few days after the pain first started. However, a few months later, the pain returns. Over the next few months or even years, they are stuck in this cycle of episodes of back pain every few months. It gradually becomes easier to trigger the pain, and it takes longer and longer to resolve every time. Eventually, a simple task like a sneeze or making a cuppa can trigger it. The reason is because the dysfunction was never corrected or treated properly in the first place, which gradually becomes more and more dysfunctional with weaker muscles and less and less muscular control.

How Does Chiropractic Work?

Now we have covered the basics, let’s dive into the main part of this blog. How does chiropractic work and what is the effect of spinal manipulation on the body?

Chiropractic manipulation has been shown to bombard the central nervous system with stimulus from the dysfunctional spinal joints and muscular mechanoreceptors. The mechanoreceptors bombard the brain with information regarding the position and function of the spinal joints and muscles, which leads to normalising the brains processing and integration with the returning motor information from the brain. As this process of spinal manipulation is repeated, the processing of sensory information restores the returning control signals from the brain, leading to increased muscular activity and improved joint positioning. Eventually, this leads to the normalisation of the joint function, resolving the pain experienced by the patient (Fig. 2). Manipulating the spinal joints improves their motion by taking the joint through its range of motion without exceeding its limits. Doing so restores the joints normal range of motion and movement pattern, whilst also creating the satisfying “pop”. It must be said that the “pop” is not required for the therapeutic outcome to be achieved.

Fig. 2 demonstrating the impact spinal manipulation has on correcting spinal dysfunction, restoring normal neurological and muscular function (adapted from Haavik & Murphy 17).

At Spriggs Chiropractic, your care plan is structured to reflect this gradual change and improvement in neurological, spinal, and muscular function. The required phases of a high frequency of treatment visits at the start of your care plan is built using the principles above. The gradual improvement in spinal function and muscular control needs frequent applications of spinal manipulation to restore the joint and neurological function quickly. Treatment frequency is gradually reduced and your exercise rehabilitation begins as you are prescribed targeted exercises to improve the strength and endurance of the spinal muscles. Increasing the muscle mass, strength and endurance of the spinal muscles is a key component to achieving the long-term improvement and reduces the risk of future flare-ups.

How Does Chiropractic Biophysics (CBP®) Work?

Chiropractic Biophysics (CBP®) works on the same principles described above with additional focus on the patient’s rehabilitation after the manipulation phase of care. CBP® has a primary focus on structural rehabilitation of the spine, whereas traditional rehabilitation programs are focused on function alone¹⁹. The structural component of any rehabilitation program is an important one, as structure dictate’s function. If we change the structure of any joint of the body, say as a result of a trauma or a surgical intervention, then the joint may not function as it once did, for better or worse.

When applying this principle to the spine, we must understand the shape and structure of the patient’s spine before we attempt to rehabilitate it. A working example of this is with a common structural change that we see in patient’s spines, forward head posture.

When we lose muscular strength of their neck muscles, say from a car crash/whiplash injury for example, the neck loses its normal C-shapes curve (lordosis) by straightening or even reversing it (kyphosis)²⁰. These two different structural changes may result in the same outcome or forward head posture, they require different treatment methods, as the structural changes result in different functional changes. In other words, as structure dictate’s function, in order to improve the spinal function, we must apply the appropriate approach to the structural changes with patient has following their injury. There is a significant body of research supporting this^20–25. Our chiropractors at Spriggs Chiropractic are CBP® trained to apply a customised rehabilitation plan to your individual needs.

I hope this blog post has sparked your interest and answered the question “How Does Chiropractic Work?” The profession has a fascinating but challenging history, but as with any medical or healthcare profession, it has it’s roots in the prominent theories of its time that evolve with new scientific discoveries. It has been a long time since holes were drilled in the heads of headache sufferers, or the application of leaches for every ache or pain. One final thought, for those who “don’t believe in Chiropractic”, belief is not required, but your ability to read the scientific evidence is. It was my father who told me to keep an open mind, but not so open that your brain falls out.

Dr Mark Spriggs DC, MChiro, MSc, PGCert, FRCC

 References:

1. Moore JS. Subluxations, Science, and the Spine: D.D. Palmer and the Origins of Chiropractic. In: Chiropractic in America: The History of a Medical Alternative. ; 1993:6.
2. Haavik H, Kumari N, Holt K, et al. The Contemporary Model of Vertebral Column Joint Dysfunction and Impact of High-Velocity, Low-Amplitude Controlled Vertebral Thrusts on Neuromuscular Function. Vol 121.; 2021. doi:10.1007/s00421-021-04727-z
3. Gatterman MI. Principles of Chiropractic. In: Chiropractic Management of Spine Related Disorders. 1st ed. Williams & Wilkins; 1990:37-54.
4. Triano JJ, Budgell B, Bagnulo A, et al. Review of methods used by chiropractors to determine the site for applying manipulation. Chiropr Man Therap. 2013;21(1):36. doi:10.1186/2045-709X-21-36
5. Nelson C. The Subluxation Question. J Chiropr Humanit. 1997;7:46-55. doi:10.1016/S1556-3499(13)60088-1
6. Guideline CP. Council on Chiropractic Clinical Practice Guideline: : Vertebral Subluxation in Chiropractic Practice.; 2003.
7. Lelic D, Niazi IK, Holt K, et al. Manipulation of dysfunctional spinal joints affects sensorimotor integration in the prefrontal cortex: A brain source localization study. Neural Plast. 2016;2016. doi:10.1155/2016/3704964
8. Sung PS, Kang YM, Pickar JG. Effect of spinal manipulation duration on low threshold mechanoreceptors in lumbar paraspinal muscles: a preliminary report. Spine (Phila Pa 1976). 2005;30(1):115-122. doi:10.1097/01.BRS.0000147800.88242.48
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14. Hodges PW, James G, Blomster L, et al. Can proinflammatory cytokine gene expression explain multifidus muscle fiber changes after an intervertebral disc lesion? Spine (Phila Pa 1976). 2014;39(13):1010-1017. doi:10.1097/BRS.0000000000000318
15. Hodges PW, James G, Blomster L, et al. Multifidus Muscle Changes After Back Injury Are Characterized by Structural Remodeling of Muscle, Adipose and Connective Tissue, but Not Muscle Atrophy: Molecular and Morphological Evidence. Spine (Phila Pa 1976). 2015;40(14):1057-1071. doi:10.1097/BRS.0000000000000972
16. James G, Blomster L, Hall L, et al. Mesenchymal Stem Cell Treatment of Intervertebral Disc Lesion Prevents Fatty Infiltration and Fibrosis of the Multifidus Muscle, but not Cytokine and Muscle Fiber Changes. Spine (Phila Pa 1976). 2016;41(15):1208-1217. doi:10.1097/BRS.0000000000001669
17. Haavik H, Murphy B. The role of spinal manipulation in addressing disordered sensorimotor integration and altered motor control. J Electromyogr Kinesiol. 2012;22(5):768-776. doi:10.1016/j.jelekin.2012.02.012
18. Haavik H, Niazi IK, Kumari N, Amjad I, Duehr J, Holt K. The potential mechanisms of high-velocity, low-amplitude, controlled vertebral thrusts on neuroimmune function: A narrative review. Med. 2021;57(6):1-26. doi:10.3390/medicina57060536
19. Harrison DE, Harrison DD, Haas JW. CBP Structural Rehabilitation of the Cervical Spine. 1st ed. Harrison Chiropractic Biophysics Seminars Inc; 2002.
20. Oakley PA, Cuttler JM, Harrison DE. X-Ray Imaging is Essential for Contemporary Chiropractic and Manual Therapy Spinal Rehabilitation : Radiography Increases Benefits and Reduces Risks. Dose-Response. 2018;16(2):0-6. doi:10.1177/1559325818781437
21. Moustafa IM, Diab AA, Taha S, Harrison DE. Addition of a Sagittal Cervical Posture Corrective Orthotic Device to a Multimodal Rehabilitation Program Improves Short- and Long-Term Outcomes in Patients With Discogenic Cervical Radiculopathy. Arch Phys Med Rehabil. 2016;97(12):2034-2044. doi:10.1016/j.apmr.2016.07.022
22. Moustafa IM, Diab AA, Hegazy F, Harrison DE. Does improvement towards a normal cervical sagittal configuration aid in the management of cervical myofascial pain syndrome: A 1- year randomized controlled trial. BMC Musculoskelet Disord. 2018;19(1). doi:10.1186/s12891-018-2317-y
23. Moustafa IM, Diab AA, Harrison DE. The effect of normalizing the sagittal cervical configuration on dizziness, neck pain, and cervicocephalic kinesthetic sensibility: a 1-year randomized controlled study. Eur J Phys Rehabil Med. 2017;53(1):57-71. doi:10.23736/S1973-9087.16.04179-4
24. Moustafa IM, Diab AA, Harrison DE. Does improvement towards a normal cervical sagittal configuration aid in the management of lumbosacral radiculopathy: A randomized controlled trial. Proc 13th World Fed Chiropr Bienn Congr / ECU Conv Athens, Greece,. 2015;Paper #184.
25. Moustafa IM, Diab AAM, Hegazy FA, Harrison DE. Does rehabilitation of cervical lordosis influence sagittal cervical spine flexion extension kinematics in cervical spondylotic radiculopathy subjects? J Back Musculoskelet Rehabil. 2017;30(4):937-941. doi:10.3233/BMR-150464