One of the problems regularly encountered when evaluating the effectiveness of chiropractic spinal manipulation is that there are numerous chiropractic spinal manipulative techniques and clinical trials rarely provide an exact means of differentiating between them. Faced with a negative studies, chiropractors might therefore argue that the result was negative because the wrong techniques were used; therefore they might insist that it does not reflect chiropractic in a wider sense. Others claim that even a substantial body of negative evidence does not apply to chiropractic as a whole because there is a multitude of techniques that have not yet been properly tested. It seems as though the chiropractic profession wants the cake and eat it.
Amongst the most commonly used is the ‘DIVERSIFIED TECHNIQUE’ (DT) which has been described as follows: Like many chiropractic and osteopathic manipulative techniques, Diversified is characterized by a high velocity low amplitude thrust. Diversified is considered the most generic chiropractic manipulative technique and is differentiated from other techniques in that its objective is to restore proper movement and alignment of spine and joint dysfunction.
Also widely used is a technique called ‘FLEXION DISTRACTION’ (FD) which involves the use of a specialized table that gently distracts or stretches the spine and which allows the chiropractor to isolate the area of disc involvement while slightly flexing the spine in a pumping rhythm.
The ‘ACTIVATOR TECHNIQUE’ (AT) seems a little less popular; it involves having the patient lie in a prone position and comparing the functional leg lengths. Often one leg will seem to be shorter than the other. The chiropractor then carries out a series of muscle tests such as having the patient move their arms in a certain position in order to activate the muscles attached to specific vertebrae. If the leg lengths are not the same, that is taken as a sign that the problem is located at that vertebra. The chiropractor treats problems found in this way moving progressively along the spine in the direction from the feet towards the head. The activator is a small handheld spring-loaded instrument which delivers a small impulse to the spine. It was found to give off no more than 0.3 J of kinetic energy in a 3-millisecond pulse. The aim is to produce enough force to move the vertebrae but not enough to cause injury.
There is limited research comparing the effectiveness of these and the many other techniques used by chiropractors, and the few studies that are available are usually less than rigorous and their findings are thus unreliable. A first step in researching this rather messy area would be to determine which techniques are most frequently employed.
The aim of this new investigation was to do just that, namely to provide insight into which treatment approaches are used most frequently by Australian chiropractors to treat spinal musculoskeletal conditions.
A questionnaire was sent online to the members of the two main Australian chiropractic associations in 2013. The participants were asked to provide information on treatment choices for specific spinal musculoskeletal conditions.
A total of 280 responses were received. DT was the first choice of treatment for most of the included conditions. DT was used significantly less in 4 conditions: cervical disc syndrome with radiculopathy and cervical central stenosis were more likely to be treated with AT. FD was used almost as much as DT in the treatment of lumbar disc syndrome with radiculopathy and lumbar central stenosis. More experienced Australian chiropractors use more AT and soft tissue therapy and less DT compared to their less experienced chiropractors. The majority of the responding chiropractors also used ancillary procedures such as soft tissue techniques and exercise prescription in the treatment of spinal musculoskeletal conditions.
The authors concluded that this survey provides information on commonly used treatment choices to the chiropractic profession. Treatment choices changed based on the region of disorder and whether neurological symptoms were present rather than with specific diagnoses. Diversified technique was the most commonly used spinal manipulative therapy, however, ancillary procedures such as soft tissue techniques and exercise prescription were also commonly utilised. This information may help direct future studies into the efficacy of chiropractic treatment for spinal musculoskeletal disorders.
I am a little less optimistic that this information will help to direct future research. Critical readers might have noticed that the above definitions of two commonly used techniques are rather vague, particularly that of DT.
Why is that so? The answer seems to be that even chiropractors are at a loss coming up with a good definition of their most-used therapeutic techniques. I looked hard for a more precise definition but the best I could find was this: Diversified is characterized by the manual delivery of a high velocity low amplitude thrust to restricted joints of the spine and the extremities. This is known as an adjustment and is performed by hand. Virtually all joints of the body can be adjusted to help restore proper range of motion and function. Initially a functional and manual assessment of each joint’s range and quality of motion will establish the location and degree of joint dysfunction. The patient will then be positioned depending on the region being adjusted when a specific, quick impulse will be delivered through the line of the joint in question. The direction, speed, depth and angles that are used are the product of years of experience, practice and a thorough understanding of spinal mechanics. Often a characteristic ‘crack’ or ‘pop’ may be heard during the process. This is perfectly normal and is nothing to worry about. It is also not a guide as to the value or effectiveness of the adjustment.
This means that the DT is not a single method but a hotchpotch of techniques; this assumption is also confirmed by the following quote: The diversified technique is a technique used by chiropractors that is composed of all other techniques. It is the most commonly used technique and primarily focuses on spinal adjustments to restore function to vertebral and spinal problems.
What does that mean for research into chiropractic spinal manipulation? It means, I think, that even if we manage to define that a study was to test the effectiveness of one named chiropractic technique, such as DT, the chiropractors doing the treatments would most likely do what they believe is required for each individual patient.
There is, of course, nothing wrong with that approach; it is used in many other area of health care as well. In such cases, we need to view the treatment as something like a ‘black box’; we test the effectiveness of the black box without attempting to define its exact contents, and we trust that the clinicians in the trial are well-trained to use the optimal mix of techniques as needed for each individual patient.
I would assume that, in most studies available to date, this is precisely what already has been implemented. It is simply not reasonable to assume that a trial the trialists regularly instructed the chiropractors not to use the optimal treatments.
What does that mean for the interpretation of the existing trial evidence? It means, I think, that we should interpret it on face value. The clinical evidence for chiropractic treatment of most conditions fails to be convincingly positive. Chiropractors often counter that such negative findings fail to take into account that chiropractors use numerous different techniques. This argument is not valid because we must assume that in each trial the optimal techniques were administered.
In other words, the chiropractic attempt to have the cake and eat it has failed.
You have asked a good question, with so many techniques being used by so many professions, what is the basic underlying mechanism? What works, what doesn’t work and what’s going on? I have been asking the same question for 25+ years, so I had a look in my research library and here are a few relevant articles:
Spinal manipulative therapy and somatosensory activation.
http://www.sciencedirect.com/science/article/pii/S105064111200017X
The Within-Session Change in Low Back Pain Intensity Following Spinal Manipulative Therapy Is Related to Differences in Diffusion of Water in the Intervertebral Discs of the Upper Lumbar Spine and L5-S1
http://www.ncbi.nlm.nih.gov/pubmed/24261925
Short-term effect of spinal manipulation on pain perception, spinal mobility, and full height recovery in male subjects with degenerative disk disease: a randomized controlled trial.
http://www.ncbi.nlm.nih.gov/pubmed/24862763
Effect of spinal manipulation on the development of history-dependent responsiveness of lumbar paraspinal muscle spindles in the cat
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4045034/?tool=pmcentrez&report=abstract
The effect of application site of spinal manipulative therapy (SMT) on spinal stiffness.
http://www.ncbi.nlm.nih.gov/pubmed/24139864
Immediate changes in neck pain intensity and widespread pressure pain sensitivity in patients with bilateral chronic mechanical neck pain: a randomized controlled trial of thoracic thrust manipulation vs non-thrust mobilization.
http://www.ncbi.nlm.nih.gov/pubmed/24880778
Instantaneous rate of loading during manual high-velocity, low-amplitude spinal manipulations.
http://www.ncbi.nlm.nih.gov/pubmed/24928638
The role of preload forces in spinal manipulation: experimental investigation of kinematic and electromyographic responses in healthy adults.
http://www.ncbi.nlm.nih.gov/pubmed/24928637
Changes in pain sensitivity following spinal manipulation: A systematic review and meta-analysis
http://www.sciencedirect.com/science/article/pii/S1050641112000065
Outcomes of Acute and Chronic Patients With Magnetic Resonance Imaging–Confirmed Symptomatic Lumbar Disc Herniations Receiving High-Velocity, Low-Amplitude, Spinal Manipulative Therapy: A Prospective Observational Cohort Study With One-Year Follow-Up
http://www.sciencedirect.com/science/article/pii/S0161475414000347
Changes in biomechanical dysfunction and low back pain reduction with osteopathic manual treatment: results from the OSTEOPATHIC Trial.
http://www.ncbi.nlm.nih.gov/pubmed/24704126
Immediate effects of spinal manipulative therapy on regional antinociceptive effects in myofascial tissues in healthy young adults.
http://www.ncbi.nlm.nih.gov/pubmed/23830709
Immediate effects of spinal manipulation on nitric oxide, substance P and pain perception.
http://www.ncbi.nlm.nih.gov/pubmed/24674816
Clinical effectiveness of manual therapy for the management of musculoskeletal and non-musculoskeletal conditions: systematic review and update of UK evidence report
http://www.chiromt.com/content/22/1/12/abstract
Quantification of Cavitation and Gapping of Lumbar Zygapophyseal Joints during Spinal Manipulative Therapy
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3501577/?tool=pmcentrez&report=abstract
Neuromechanical characterization of in vivo lumbar spinal manipulation. Part I. Vertebral motion.
http://www.ncbi.nlm.nih.gov/pubmed/14673406
Neuromechanical characterization of in vivo lumbar spinal manipulation. Part II. Neurophysiological response.
http://www.ncbi.nlm.nih.gov/pubmed/14673407
Biomechanical and neurophysiological responses to spinal manipulation in patients with lumbar radiculopathy.
http://www.ncbi.nlm.nih.gov/pubmed/14739869
The Effect of Duration and Amplitude of Spinal Manipulative Therapy (SMT) on Spinal Stiffness
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3477278/?tool=pmcentrez&report=abstract
Immediate reduction in temporal sensory summation after thoracic spinal manipulation
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3092807/?tool=pmcentrez&report=abstract
Immediate effects from manual therapy: much ado about nothing?
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3172950/?tool=pmcentrez&report=abstract
The neurophysiological effects of a single session of spinal joint mobilization: does the effect last?
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3143008/?tool=pmcentrez&report=abstract
Spinal Manipulative Therapy–Specific Changes in Pain Sensitivity in Individuals With Low Back Pain (NCT01168999)
http://www.jpain.org/article/S1526-5900%2813%2901300-X/abstract
Do manual therapies help low back pain? A comparative effectiveness meta-analysis.
http://www.ncbi.nlm.nih.gov/pubmed/24480940
Neural Responses to the Mechanical Parameters of a High-Velocity, Low-Amplitude Spinal Manipulation: Effect of Preload Parameters
http://www.sciencedirect.com/science/article/pii/S0161475413002716
Changes in biochemical markers of pain perception and stress response after spinal manipulation.
http://www.ncbi.nlm.nih.gov/pubmed/24450367
Changes in postural activity of the trunk muscles following spinal manipulative therapy
http://www.sciencedirect.com/science/article/pii/S1356689X06001093
Is manipulative therapy more effective than sham manipulation in adults?: a systematic review and meta-analysis
http://www.chiromt.com/content/21/1/34
Neurophysiological effects of spinal manipulation
http://www.sciencedirect.com/science/article/pii/S152994300200400X
Efficacy of spinal manipulation and mobilization for low back pain and neck pain: a systematic review and best evidence synthesis
http://www.sciencedirect.com/science/article/pii/S1529943003001773
Physiological Responses to Spinal Manipulation Therapy: Investigation of the Relationship Between Electromyographic Responses and Peak Force
http://www.sciencedirect.com/science/article/pii/S0161475413002297
Effectiveness of Physical Therapist administered spinal manipulation forEffectiveness of physical ther the treatment of low back pain: a systematic review of the literature.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3537457/?tool=pmcentrez&report=abstract
Spinal high-velocity low amplitude manipulation in acute nonspecific low back pain: a double-blinded randomized controlled trial in comparison with diclofenac and placebo.
http://www.ncbi.nlm.nih.gov/pubmed/23026869
Does maintained spinal manipulation therapy for chronic nonspecific low back pain result in better long-term outcome?
http://www.ncbi.nlm.nih.gov/pubmed/21245790
Manipulative therapy versus education programs in chronic low back pain.
http://www.ncbi.nlm.nih.gov/pubmed/7644961
Chiropractic and rehabilitative management of a patient with progressive lumbar disk injury, spondylolisthesis, and spondyloptosis.
http://www.ncbi.nlm.nih.gov/pubmed/16396733
Manipulation or microdiskectomy for sciatica? A prospective randomized clinical study.
http://www.ncbi.nlm.nih.gov/pubmed/21036279
Chiropractic spinal manipulation for back pain. E. Ernst
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1724640/?tool=pmcentrez&report=abstract
Spinal manipulative therapy for chronic low-back pain
http://summaries.cochrane.org/CD008112/BACK_spinal-manipulative-therapy-for-chronic-low-back-pain
Response of muscle proprioceptors to spinal manipulative-like loads in the anesthetized cat.
http://www.ncbi.nlm.nih.gov/pubmed/11174689
The effective forces transmitted by high-speed, low-amplitude thoracic manipulation.
http://www.ncbi.nlm.nih.gov/pubmed/11698887
Spinal manipulation force and duration affect vertebral movement and neuromuscular responses.
http://www.ncbi.nlm.nih.gov/pubmed/16378668
Physical therapy treatment choices for musculoskeletal impairments.
http://www.ncbi.nlm.nih.gov/pubmed/9037215
Manual therapy followed by specific active exercises versus a placebo followed by specific active exercises on the improvement of functional disability in patients with chronic non specific low back pain: a randomized controlled trial.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3518179/?tool=pmcentrez&report=abstract
Relationship between Biomechanical Characteristics of Spinal Manipulation and Neural Responses in an Animal Model: Effect of Linear Control of Thrust Displacement versus Force, Thrust Amplitude, Thrust Duration, and Thrust Rate.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3563165/?tool=pmcentrez&report=abstract
The mechanisms of manual therapy in the treatment of musculoskeletal pain: a comprehensive model.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775050/?tool=pmcentrez&report=abstract
Effect of Seated Thoracic Manipulation on Changes in Scapular Kinematics and Scapulohumeral Rhythm in Young Asymptomatic Participants: A Randomized Study.
http://www.jmptonline.org/article/S0161-4754%2813%2900204-2/abstract
Two-year follow-up of a randomized clinical trial of spinal manipulation and two types of exercise for patients with chronic neck pain.
http://www.ncbi.nlm.nih.gov/pubmed/12438988
High-velocity low-amplitude spinal manipulation for symptomatic lumbar disk disease: a systematic review of the literature.
http://www.ncbi.nlm.nih.gov/pubmed/16096043
Basic science research related to chiropractic spinal adjusting: the state of the art and recommendations revisited.
http://www.ncbi.nlm.nih.gov/pubmed/17142166
Lumbar traction: a review of the literature.
http://www.ncbi.nlm.nih.gov/pubmed/7827634
Manipulation or microdiskectomy for sciatica? A prospective randomized clinical study.
http://www.ncbi.nlm.nih.gov/pubmed/21036279
Mechanisms and effects of spinal high-velocity, low-amplitude thrust manipulation: Previous theories
http://www.ncbi.nlm.nih.gov/pubmed/12021744
Chiropractic technique procedures for specific low back conditions: characterizing the literature.
http://www.ncbi.nlm.nih.gov/pubmed/11514818
Distraction manipulation of the lumbar spine: a review of the literature.
http://www.ncbi.nlm.nih.gov/pubmed/16396738
Loads in the lumbar spine during traction therapy.
http://www.ncbi.nlm.nih.gov/pubmed/11552865
Relationship between techniques taught and practice behavior: education and clinical correlation.
http://www.ncbi.nlm.nih.gov/pubmed/10029947
Rating specific chiropractic technique procedures for common low back conditions.
http://www.ncbi.nlm.nih.gov/pubmed/12532145
Lumbar spine traction: evaluation of effects and recommended application for treatment.
http://www.ncbi.nlm.nih.gov/pubmed/10903582
Spinal manipulative therapy for low back pain. A meta-analysis of effectiveness relative to other therapies.
http://www.ncbi.nlm.nih.gov/pubmed/12779297
Efficacy of spinal manipulation and mobilization for low back pain and neck pain: a systematic review and best evidence synthesis.
http://www.ncbi.nlm.nih.gov/pubmed/15125860
Neuromechanical characterization of in vivo lumbar spinal manipulation. Part I. Vertebral motion.
http://www.ncbi.nlm.nih.gov/pubmed/14673406
Effect of spinal manipulation thrust magnitude on trunk mechanical activation thresholds of lateral thalamic neurons.
http://www.ncbi.nlm.nih.gov/pubmed/24928636
Spinal reflex attenuation associated with spinal manipulation.
http://www.ncbi.nlm.nih.gov/pubmed/11013505
Functional MRI of the rat lumbar spinal cord involving painful stimulation and the effect of peripheral joint mobilization.
http://www.ncbi.nlm.nih.gov/pubmed/12884326
Central neuronal plasticity, low back pain and spinal manipulative therapy.
http://www.ncbi.nlm.nih.gov/pubmed/15195039
Immediate effects of spinal manipulation on thermal pain sensitivity: an experimental study
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1578563/?tool=pmcentrez&report=abstract
Hypoalgesia post-manipulative therapy: a review of a potential neurophysiological mechanism.
http://www.ncbi.nlm.nih.gov/pubmed/11327789
A pilot study of the manual force levels required to produce manipulation induced hypoalgesia.
http://www.ncbi.nlm.nih.gov/pubmed/12034124
An investigation of the interrelationship between manipulative therapy-induced hypoalgesia and sympathoexcitation.
http://www.ncbi.nlm.nih.gov/pubmed/9777544
Spinal manipulation alters electromyographic activity of paraspinal muscles: a descriptive study.
http://www.ncbi.nlm.nih.gov/pubmed/16182019
The mechanisms of manual therapy in the treatment of musculoskeletal pain: a comprehensive model.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2775050/?tool=pmcentrez&report=abstract
Short-term effects of manipulation to the upper thoracic spine of asymptomatic subjects on plasma concentrations of epinephrine and norepinephrine-a randomized and controlled observational study.
http://www.ncbi.nlm.nih.gov/pubmed/22343005
Understanding inhibitory mechanisms of lumbar spinal manipulation using H-reflex and F-wave responses: a methodological approach.
http://www.ncbi.nlm.nih.gov/pubmed/22878176
The articles above are from chiro’s, physio’s, osteo’s and medico’s. They are all consistent and seem standardized in describing the spinal manipulation in regards to velocity (high, low, traction, distraction) force, amplitude and duration. Few name a specific technique.
Apologies for the lengthy reply, but this topic is of great interest and has a huge bearing on why I practice and how I practice.
Still asking why, some questions have been answered yet even more questions pop up!
Thanks, Thinkin’ Chiro, I am sure that your hard work posting references from your library will convince EE and he will like you now and like everything you do to help people.
Dear Professor Ernst,
I wish make a statement. The diversified technique is more of a system and was constructed from other technique systems. Some choose to view it as how the martial art Jeet Kun-Do was constructed from several other martial arts. It is a series of different moves that is quite standardized and usually taught that way. Some instructors or practitioners may have their own twist, but that should be of minimal influence to any result.
There are many other technique systems like that of “activator (AT)” which the argument should refer to if I am not mistaken.
“Flexion Distraction” is more of a modality than a technique system. It would be more like using a screwdriver instead of a drill. It is viewed as less invasive and the belief is that it works better for acute patients with discogenic problems. The hypothesis is that it creates a negative pressure within the disc that withdraws some of the material of the disc for the duration of the treatment.
These techniques may or may not work, regardless I wished to clarify what I tried to do above. I am under the assumption that it is very difficult to understand the subtle differences between techniques and technique systems from outside the profession. I hope this was of some benefit and not just a complete waste of your time. I have not made any references, due to the complexity of my statements and they should therefore just be view as personal views.
Did you just spend all that time linking to articles on the association website? Wow, I am amazed you thought that would convince anyone. Tell ya what I don’t believe in God, can you link some Bible verses as proof for him as well?