This section will examine manipulation of the spine, as practised by chiropractors and osteopaths but many others too. It will examine possible modes of action, the evidence available, safety and regulation.
It is divided into the following sections:
- Mechanism of Action
- Dangers and Contraindications
- Acquiring Evidence
- Placebo Control
- Evidence About Manipulation
- Further Resources
- Site Index
If you wish to go directly to one of these sections, click on the title in blue.
Manipulation of the spine is practised principally by chiropractors and osteopaths but many others too. This section will examine possible modes of action, the evidence available, safety and regulation. Some people manipulate peripheral joints too but as there is far less evidence about this, it will not be examined. Basically, there is manipulation of the neck, the thoracic spine and the lumbar spine.
Manipulation dates back many centuries and probably millennia. The treatment involves taking a joint to its full range of movement and then moving it just a little further. This is usually applied to parts of the spinal column, most often the lumbar spine, less often the neck and sometimes the thoracic spine. It can be used on peripheral joints too, but this article will concentrate on manipulation of the spinal column, called the axial skeleton. Manipulation for other conditions will be mentioned briefly.
Over the years, manipulators have come from many backgrounds, including the very basic bone setters with little or no medical knowledge. Chiropractors and osteopaths are comparatively recent in origin and are unique amongst CAM practitioners in that they are regulated by Act of Parliament. There is a General Chiropractic Council and a General Osteopathy Council to oversee standards and registration. Some doctors and physiotherapists also manipulate and there is nothing to prevent a totally unregistered practitioner from practising, so long as he does not pretend to be registered. It is very difficult to know how many people practice manipulation and how commonly it is performed.
Many manipulators claim to be realigning misplaced bones or reducing slipped discs. Dislocation occurs when a bone is pulled out of the joint but a partial dislocation is called a subluxation. This is a term that manipulators often use, but high resolution x-rays and MRI scans have failed to show any displacement in such lesions.
A slipped disc is also called a herniated disc or a prolapsed intervertebral disc. The discs between the vertebrae act as shock-absorbers. They have a soft, spongy nucleus pulposus and a hard, fibrous annulus fibrosus. If the annulus fibrosus is damaged or torn, the nucleus pulposus can ooze out. As shown in the picture, this can press on nerves. It is hard to imagine that manipulation will return the prolapsed contents of the disc to its original place, where the annulus can heal. Indeed, if proper imaging such as MRI shows such a lesion, I would suggest that it is a contraindication to manipulation which could make it worse. Diagnosing a prolapsed disc on a plain x-ray is very difficult.
As the nucleus prolapses, it can impinge on the sciatic nerve causing sciatica. However, most cases of sciatica are not caused by a slipped disc. The brain is very good at locating touch or pain on the skin, but not so good inside the body. Hence, pain in the area supplied by the same nerves as the sciatic nerve causes pain in the distribution of the sciatic nerve, down the back of the leg. Higher up, it may be down the front of the thigh. If there is pressure on a nerve, this may suppress the ankle or knee reflex, depending on the level. However, I do not intend to go further with the clinical examination of the patient with back pain. My point is that disc problems do occur, but they are grossly over-diagnosed by manipulators.
Manipulation as a form of treatment is recorded as far back as 2700BC in China and Hippocrates and Galen both used it.
Osteopathy was founded in 1874 by Andrew Taylor Still, a doctor in rural Missouri, USA, who became disillusioned with the medicine of the day when two of his children died of meningitis. This was well before the advent of antibiotics and osteopathy would not have helped meningitis. He founded osteopathy as an independent system of medicine. Osteopathy means disease of bones, from the Greek word osteon meaning bone and -pathy, from patheia, meaning suffering, disease or feeling. As a system of treating disease by the manipulation of bones, it dates from 1889. According to one source, the therapeutic system of treatment he devised has its origin in a number of treatment philosophies of the time including phrenology, mesmerism, magnetic healing, bone setting and conventional medicine.
Chiropractic was founded by Daniel David Palmer in 1895. It is also derived from Greek. Cheir means hand and praktos means done. It translates as done by hand. In 1895, Palmer met a janitor who claimed to have lost his hearing when he moved and heard a “pop” in his back. Palmer noted that the janitor had a “vertebra out of place.” The man lay face down on the floor while he manipulated the man’s spine “gently coaxing it into alignment”. The next day the janitor claimed that he could hear again. I can think of no anatomical explanation for this. I wonder if maybe some ear wax moved or catarrh drained. Palmer was very interested in spiritualism and the “energetic” healing traditions that were current in the late 19th century.
With both osteopathy and chiropractic, pretence to be a whole system of healing has caused friction with conventional medicine. It is not a whole system of healing, but may be of value in orthopaedic problems, especially back pain at the various levels.
AJ Cronin’s book The Citadel was first published in 1923 and whilst it is fiction, much is based on his experience as a doctor. Association with unregistered practitioners was one of the cardinal sins of the General Medical Council (GMC). He recounts how a doctor had been erased from the medical register (struck off) for anaesthetising for Jarvis the manipulator.
It was some time later before manipulation came to the medical fraternity. In Australia in the 1950s, Geoffrey Maitland was a pioneer of manipulation within a setting of physiotherapy. His teachings are much respected.
Many doctors have used manipulation over the years and the best known is Dr James Cyriax. He was a controversial character whose books on orthopaedic examination rather than treatment are held in high regard. With regard to manipulation he is regarded as a luminary by some, but others argue that his dogmatic and unscientific stance set back the cause of manipulation. His writings and teachings suggest that he thought that manipulation of the lumbar spine replaces a slipped disc. Even in the days before CT and MRI scans, I thought that this was fanciful. He was also accused of using excessive force in his techniques.
It may be a reflection of his practice or his personality that he spent 30 years as a consultant physician at St Thomas’ Hospital in London but was never elected to Fellowship of the Royal College of Physicians of London. For a consultant physician at a London teaching hospital, that is quite exceptional.
Techniques are legion and there are said to be around 150 schools of manipulation. The most important difference is the action of the rotation of manipulation. It may be a small range of movement with high velocity or a larger range of movement with low velocity. There is considerable debate about the relative safety and efficacy of each but very little evidence to support any proposition.
There are two pictures of manipulation of the neck, one with the patient lying and one with the patient sitting. There are two pictures of different techniques to manipulate the thoracic spine and one for the lumbar spine. There are very many different techniques that are used. Flexing the neck fixes the upper spine and manipulates the lower joints whilst extending it fixes the lower joints and manipulates the upper joints. The opposite is true for the lumbar spine.
Manipulation should only follow a proper history and examination to ascertain the nature and level of the problem and to identify any contraindication to manipulation. Identifying the exact level of the cause is not as easy as it seems because spinal reflexes can cause pain a few segments above or below the source. Examination will include palpation for muscle spasm and tenderness and just running two fingers down either side of the spine may reveal differences in friction along the skin. This is because changes to the autonomic nervous system may cause differences in sweating.
Being manipulated feels strange but it is not normally painful. There is usually a slight clicking or popping sound but not always. There may be a significant amount of muscle spasm around the joint if there is much pain. Pain killers and massage may help to relieve this before treatment or excessive pain and hence resistance may make the treatment impossible.
Mechanism of Action
The mode of action of manipulation is uncertain. The idea that there is a slight subluxation (minor dislocation) of the joints that then pop back is not supported by the evidence. The clicking or popping sound that often accompanies manipulation can be most impressive, but it is thought to be caused by gas bubbles coming out of solution in the stretched joint, as with clicking knuckles. There appears to be no correlation between the presence or impressiveness of the sound and the effectiveness of the procedure.
The most feasible suggestion for the mode of action of manipulation is that it overstretches the pain receptors of the joints and, in doing so closes the pain pathway as suggested by the gate theory of pain. This mechanism is probably similar to traction, used for back pain, which does not pull apart the vertebrae of the lumbar spine to any measurable amount, even with very heavy weights. I shall not go into the neurology of pain, but a fairly simple explanation is available.1Pain and Why It Hurts The gate pathway is also overloaded by rubbing a pain or scratching an itch. Itch, pain and tickle have similar mechanisms and nervous pathways.
If the mechanism of action is overload of the pain pathways, then presumably manipulation under anaesthetic has no benefit. Orthopaedic surgeons perform manipulation under anaesthetic, but the aim is to break down adhesions and this is a very different procedure.
Dangers and Contraindications
Much has been made of the potential dangers of spinal manipulation and whilst they do exist, they have almost invariably been grossly overstated. Contraindication is a medical term meaning a reason for not doing something, usually because it is too dangerous.
Before manipulating it is important to form a working diagnosis. This will involve history and examination but not normally special investigations such as blood tests and imaging. The routine use of x-rays is to be depreciated. X-ray of the lumbar spine offers little information, whilst the dose of radiation is equivalent to 120 chest x-rays.2(Back Pain. Report of a Clinical Standards Advisory Group on Back Pain. 1994). Nevertheless, many non-medical manipulators are very keen on x-rays and their equipment may be less modern than that in hospitals departments and so give higher doses of radiation. It seems to impress the patients, but if they knew how much they had been irradiated, they may be less enthusiastic.
The diagnosis is usually simple back pain. Sinister causes of back pain must be excluded. If imaging is required, an MRI scan (magnetic resonance imaging) gives far more information than a plain x-ray but it is also much more expensive. MRI scans are very good at showing soft tissue including discs and the spinal cord. If a fracture of part of a vertebra is suspected a CT (computerised tomography) scan gives the best picture of bone. Manipulating a back that is weakened by Paget’s disease, multiple myeloma or secondary cancer may produce collapse of the vertebrae and compression of the spinal cord resulting in paralysis. The nerves coming off the bottom of the spinal cord look like a horse’s tail and so it is called the cauda equina. Cauda equina syndrome is compression of these nerves and it requires immediate referral to a neurosurgeon.
I shall not expand on the diagnosis, but it is important for practitioners to recognise this whether they are doctors or not. Cauda equina compression resulting from manipulation is extremely rare.3Cauda equina syndrome in manipulation of the lumbar spine. The ability to recognise “red flags” and to refer on rather than manipulating inappropriate cases is one reason for professional regulation. Despite the very widespread use of manipulation, serious complications as a result of manipulation of the lumbar spine are very few.
Where there have been serious problems from manipulation, they have most often been from manipulation of the neck. The spinal cord fills more of the vertebral canal in the neck than in the lumbar region and so any problem, such as a small bleed, is far more likely to press on the spinal cord. In addition, the shearing stresses of manipulation have been known to tear or cause dissection of the carotid or vertebro-basilar arteries. These arteries supply the brain and so this can cause a stroke. In rheumatoid arthritis there is weakness of the ligament holding the odontoid peg of a vertebra high in the neck. Manipulation may cause rupture and slippage of the joint between the neck and skull with high spinal cord compression. This will cause paralysis and loss of sensation. At such a high level it would paralyse the nerves to the diaphragm and cause death as breathing is longer be possible. Rheumatoid arthritis is an absolute contraindication to manipulation, especially of the neck.
Sometimes neurologists or neurosurgeons have scoured the neurology wards to find victims of manipulation and these small series can be very poignant. However, they give no indication of the degree of risk involved.4Manipulation of the cervical spine: a systematic review of case reports of serious adverse events It is difficult to estimate the number of manipulations performed annually because of the varied background of those who perform them. Stroke would seem to be a rare and unpredictable event following manipulation and it cannot be blamed on any specific technique.5Stroke, cerebral artery dissection, and cervical spine manipulation Where estimates have been made, they usually suggest that the risk of serious adverse outcome from manipulating the neck is between 2 per million and 0.5 per million procedures. In other words, it takes 2 million procedures to produce somewhere between 1 and 4 disasters. The risk for the lower back is much lower.
To put this into perspective, suppose that a practitioner manipulates five necks each morning and five each afternoon, five days a week, taking two weeks holiday a year. He would perform 2,500 manipulations of the neck per year. If his professional lifetime is 40 years, and most people have more than 2 weeks holiday a year, he would perform 100,000 manipulations of the neck in his lifetime. If the risk of adverse outcome is the higher figure of 2 per million, then, on average, one practitioner in five would expect to have one severe adverse outcome in his entire professional lifetime.
This is very much safer than the prescription of non-steroidal anti-inflammatory drugs such as ibuprofen or diclofenac. One study concluded that based on the number of practicing chiropractors and neurologists in Canada, 1 of every 48 chiropractors and 1 of every 2 neurologists would have been made aware of a vascular complication from manipulation of the neck during their practice lifetime. Being aware does not necessarily mean that it was their patient. They estimated the risk of neurological complications as fewer than 1 in 5 million treatments.6Clinical perceptions of the risk of vertebral artery dissection after cervical manipulation: the effect of referral bias
Risks have been calculated as per manipulation and not per patient. Patients usually require a course of treatment that involves several manipulations and the same person may return for treatment several times. With such small numbers of complications and so many techniques, it is impossible to ascertain which are safer and which are more dangerous. Indeed, calculations to determine the incidence of serious adverse effects are beset by the problem of knowing just how many manipulations are done each year.
The following should be seen as contraindications to manipulation at any level of the back:
- Any potential sinister cause of back pain, including a history of malignancy that may spread to bone
- Patient on anticoagulants or with a clotting disorder
- Any neurological disease
- Cauda equina syndrome as mentioned above
- Active inflammatory arthritis or even quiescent rheumatoid arthritis
In addition, the following are contraindications to manipulation of the neck:
- Known disease of the blood vessels to the brain, eg previous stroke
- High blood pressure, not well controlled
In view of the increasing risk of sinister causes of back pain with advancing age and the increased incidence of arterial disease, increasing age should be seen as a relative contraindication to manipulation, especially for the neck.
The gold standard for clinical research is the Randomised Controlled Trials with double blind placebo control. This is relatively easy for medicines. For physical treatments, a placebo control is much more difficult, as has been discussed with acupuncture. For this reason, many physical treatments in conventional medicine have a poor evidence base. This includes much physiotherapy and many surgical interventions. Sham surgery would neither gain patient consent nor ethics committee approval.
A randomised controlled trial of manipulation produces a number of problems:
- Over 90% of people pay for CAM treatment and so are likely to want what they pay for directly and not to risk paying to be in the control group. Trials within the NHS tend to be easier to arrange.
- Often, manipulation is not the only form of treatment. There may be pain relief prescribed and massage to reduce muscle spasm. There may be advice. This does not negate a trial so long as manipulation is the only variable.
- It is important to use a validated method to assess outcome. For manipulation this will usually be a validated pain and disability score such as the Oswestry score.
- Sham treatment can be very difficult to achieve. It should seem the same to the patient, but it should not have any discernible benefit.
- There must be analysis by intention to treat. This means that if a patient is put in the manipulation group but perhaps pain and muscle spasm prevent the procedure, this must be analysed in the manipulation group and not in the control.
Of these problems, by far the most difficult is placebo control. If controlled trials have a placebo that has a therapeutic effect, the difference between the two groups will be diminished, obscuring any benefit from the investigated intervention. The ideal placebo is, to the patient, in all ways like the intervention but has no effect. Sham manipulation can take several forms, none of which is satisfactory.
- The practitioner may take the joints through the range of movement but omit the final thrust. The final thrust, with or without the popping or cracking sound from the joints, is impressive and the patient is unlikely to be blind to the placebo state. There may also be some benefit from just taking the joints through to the extreme of movement. This is called mobilisation rather than manipulation.
- The most common sham is to manipulate the wrong level. There are two problems with this: One is that the diagnosis of the precise level is not very accurate. Spinal reflexes can mean that the apparent level of the lesions may be a little higher or lower than suspected. The other is that it is not possible to be precise about exactly which level is manipulated.
These difficulties make placebo control very difficult and it is tempting to make any trial open label, meaning that the patient knows in which group he is. There are some problems with this:
- If manipulation has a strong placebo effect, this will be unbalanced without a control. The more we know about the placebo response, the more impressive it becomes.
- If other modalities such as medication for pain and massage are involved, it may affect the subject’s enthusiasm for these.
- Perhaps one group is sent to a chiropractor or osteopath and the other group is given a prescription and just sent home. A good practitioner will not only manipulate but will discuss such problems as ergonomics at work, in the car and at home as well as exercise and mobility. The fact that someone is also taking a great interest in the patient, talking to him and discussing the problems is very therapeutic. Interaction with the practitioner is certainly very important in terms of patient satisfaction.7Factors associated with patient satisfaction with chiropractic care The discussion and advice that osteopaths or chiropractors offer may be very valuable, whether the manipulation is beneficial or not.
In view of the immense difficulties of placebo control, an open label trial is very attractive. Some people may argue that a placebo response is not important so long as the patient gets better. Such trials are not without merit, but they ask a different question. A placebo-controlled trial asks, does manipulation produce benefit in its own right? An open label trial asks does manipulation and all that is involved therein, perhaps including a consultation with the practitioner, have benefit over other forms of management? The Medical Research Council conducted a trial to compare chiropractic manipulation with standard hospital outpatient treatment for mechanical low back pain.8 Low back pain of mechanical origin: randomised comparison of chiropractic and hospital outpatient treatment The result was promising for manipulation.
Evidence About Manipulation
The volume of papers and the variety of quality make the use of reviews most attractive. A review of reviews from 1995 had concluded that the majority of the reviews found that spinal manipulation is an effective treatment for low back pain.9The relationship between methodological quality and conclusions in reviews of spinal manipulation. The reviews with a relatively high methodological quality had a positive conclusion but strong conclusions were precluded by the overall low quality of the reviews. A systematic review of systematic reviews from the Department of Complementary Medicine in Exeter in 2006 has produced much controversy.10A systematic review of systematic reviews of spinal manipulation Their conclusion was that collectively, there was not enough evidence to recommend manipulation for any condition. Unsurprisingly, there were many responses from practitioners claiming to refute this conclusion. It would be interesting to know if funnel plotting would demonstrate selective publication of positive results as was found with homeopathy.
The reviews with the most positive results do tend to have the lowest rigour and to be written by chiropractors or osteopaths,11Sources of bias in reviews of spinal manipulation for back pain but they are the people who do the treatment and who need to know if what they do is effective. However, human nature makes it most unlikely that they will willingly form the conclusion that what they have trained for and how they have been earning their living, is totally useless. On the other hand, this may be said of any practitioner in any field.
A Cochrane review of 200412Spinal manipulative therapy for chronic low back pain concluded that there is no evidence that spinal manipulative therapy is superior to other standard treatments for patients with acute or chronic low-back pain. The UK(BEAM) trial was a “pragmatic randomised trial” based on 181 general practices. BEAM stands for back pain, exercise and manipulation. It concluded that relative to “best care” in general practice, manipulation followed by exercise achieved a moderate benefit at three months and a small benefit at 12 months. Spinal manipulation achieved a small to moderate benefit at three months and a small benefit at 12 months.13United Kingdom back pain exercise and manipulation (UK BEAM) randomised trial Exercise achieved a small benefit at three months but not 12 months. In terms of value for money it concluded that spinal manipulation is a cost-effective addition to “best care” for back pain in general practice. Manipulation alone probably gives better value for money than manipulation followed by exercise.14Cost effectiveness of physical treatments for back pain in primary care.
The volume of evidence for treatment of neck pain by manipulation is rather less than for low back pain. A Cochrane review15Manipulation or Mobilisation for mechanical neck disorders. found that mobilisation and/or manipulation when used with exercise are beneficial for persistent mechanical neck disorders with or without headache. Compared to one another, neither was superior. Manipulation of the neck appears to be helpful for headache originating from the upper neck.16Efficacy of spinal manipulation for chronic headache
In 2019, a systematic review and meta-analysis to examine17Benefits and harms of spinal manipulative therapy for the treatment of chronic low back pain concluded that it produces similar effects to recommended therapies for chronic low back pain, but it seems to be better than non-recommended interventions for improvement in function in the short term. I have done some manipulation in my time and I would agree that whilst it appears to offer short-term benefit, this may not last. The review also advises that clinicians should inform their patients of the potential risks of adverse events associated with the procedure. As we have seen, serious adverse events are very rare and the paper stated that most of the observed adverse events were musculoskeletal related, transient in nature, and of mild to moderate severity. They were not in the order of strokes or spinal cord compression. One study with a low risk of selection bias and powered to examine risk (n=183) found no increased risk of an adverse event (relative risk 1.24, 95% confidence interval 0.85 to 1.81) or duration of the event (1.13, 0.59 to 2.18) compared with sham manipulation. In one study, the Data Safety Monitoring Board judged one serious adverse event to be possibly related to the treatment.
A Cochrane review found that there was no benefit from the use of manipulation to treat dysmenorrhoea (painful periods). There is no evidence of benefit from manual therapies in asthma. RCTs of chiropractic for pathology outside the spinal column include: treatment of fibromyalgia, carpal tunnel syndrome, infantile colic, otitis media (middle ear infection), dysmenorrhoea (painful periods) and chronic pelvic pain. There is no evidence to support the use of manipulation in any of these.18Chiropractic manipulation for non-spinal pain- a systematic review Cranial osteopathy has been advocated for treating infantile colic, glue ear and improving childhood asthma but there are no RCTs to be found and anecdotes of improvement in these conditions may well represent natural history rather than benefit of treatment. This means a normal progress irrespective of intervention. Neither rationale nor evidence supports the use of manipulation for conditions that are not musculoskeletal in origin.
Manipulation has been used very extensively for a very long time. There is a vast range of techniques and it is impossible to state if any is outstandingly good or outstandingly bad in terms of efficacy or safety. The risk of adverse events is extremely low but rather more likely to follow manipulation of the neck than the lumbar spine.
Despite extensive research of variable quality, it is impossible to be firm about its place, if any, in treatment. It may well be beneficial for musculoskeletal disorders such as simple back pain or neck pain but for other disorders such as dysmenorrhoea or glue ear it is useless. It should be seen as a treatment for back pain at various levels rather than a system of healing for a variety of conditions.
There does not seem to be a valid method of applying a randomised double-blind placebo controlled trial. Pragmatic, open label treatment has been assessed. There are many anecdotes of people who walk into a consultation bent in pain, and walk out upright, but the benefit with time is more dubious. If manipulation simply blocks the pain gate, it can be expected to have just temporary benefit. However, as pain causes muscle spasm that pulls on local structures and causes more pain, breaking this vicious cycle may be beneficial and it may require several treatments. Combined treatment, along with analgesia (pain relied), massage and exercise would seem appropriate.
The negative reviews of manipulation have perhaps been too rigorous in their expectations and they have interpreted failure to demonstrate clear and convincing benefit by vigorous methodology as evidence for lack of efficacy. Lack of evidence of effect and evidence of lack of effect are not the same. However, it does seem that if manipulation is beneficial, it is more so in the short than the medium or long term. Individual success stories may also be diluted in the numbers in trials.
If there is still pain after manipulation, the use of drugs and massage to reduce muscle spasm is important. They may also be necessary before manipulation can be performed as pain and spasm may prevent it.
Spinal manipulation may well have a part to play in treatment regimes, but its precise place is yet to be determined. On the basis of primum non nocere, it must be judged as very safe, but not totally safe. However, nothing is completely safe, and that includes drug treatment.
Osteopaths and chiropractors do not just manipulate but they spend time talking to their patients about aggravating factors at home and at work and how to reduce risk. This ergonomic assessment is very valuable and it is something that the general practitioner may not have the time or expertise to offer. Whether or not they manipulate and whether or not it is beneficial, their overall contribution to the management of back pain, which causes so much suffering and loss of time from work, should not be underestimated.
- General Osteopathic Council.
- General Chiropractic Council.
- College of Osteopaths.
- Royal College of Chiropractors
- Chiropractic. NHS.
- Osteopathy. NHS.
- Neuroscience for kids. Pain.
- Back Pain. Report of a Clinical Standards Advisory Group on Back Pain. 1994 HMSO £14.95. ISBN 0-11-321887-7.
- Haldeman S, Rubinstein SM; Cauda equina syndrome in patients undergoing manipulation of the lumbar spine. Spine. 1992 Dec;17(12):1469-73.
- Ernst E Manipulation of the cervical spine: a systematic review of case reports of serious adverse events, 1995-2001. Med J Aust. 2002 Apr 15;176(8):376-80.
- Haldeman S, Kohlbeck FJ, McGregor M; Stroke, cerebral artery dissection, and cervical spine manipulation therapy. J Neurol. 2002 Aug;249(8):1098-104.
- Haldeman S, Carey P, Townsend M, et al; Clinical perceptions of the risk of vertebral artery dissection after cervical manipulation: the effect of referral bias. Spine J. 2002 Sep-Oct;2(5):334-42.
- Gaumer G; Factors associated with patient satisfaction with chiropractic care: survey and review of the literature. J Manipulative Physiol Ther. 2006 Jul-Aug;29(6):455-62.
- Meade TW, Dyer S, Browne W, et al; Low back pain of mechanical origin: randomised comparison of chiropractic and hospital outpatient treatment. BMJ. 1990 Jun 2;300(6737):1431-7. [full text]
- Assendelft WJ, Koes BW, Knipschild PG, et al; The relationship between methodological quality and conclusions in reviews of spinal manipulation. JAMA. 1995 Dec 27;274(24):1942-8.
- Ernst E, Canter PH; A systematic review of systematic reviews of spinal manipulation.; J R Soc Med. 2006 Apr;99(4):192-6.
- Canter PH, Ernst E; Sources of bias in reviews of spinal manipulation for back pain. Wien Klin Wochenschr. 2005 May;117(9-10):333-41.
- Assendelft WJ, Morton SC, Yu EI, et al; Spinal manipulative therapy for chronic low back pain.; Cochrane Database Syst Rev. 2004;(1):CD000447.
- No authors listed; United Kingdom back pain exercise and manipulation (UK BEAM) randomised trial: effectiveness of physical treatments for back pain in primary care. BMJ. 2004 Dec 11;329(7479):1377. Epub 2004 Nov 19.
- No authors listed; United Kingdom back pain exercise and manipulation (UK BEAM) randomised trial: cost effectiveness of physical treatments for back pain in primary care. BMJ. 2004 Dec 11;329(7479):1381. Epub 2004 Nov 19.
- Gross A, Miller J, D’Sylva J, Burnie SJ, Goldsmith CH, Graham N, Haines T, Brønfort G, Hoving JL. Manipulation or Mobilisation for mechanical neck disorders. Cochrane Database of Systematic Reviews 2010, Issue 1. Art. No.: CD004249.
- Bronfort G, Assendelft WJ, Evans R, et al; Efficacy of spinal manipulation for chronic headache: a systematic review. J Manipulative Physiol Ther. 2001 Sep;24(7):457-66.
- Rubinstein SM, de Zoete A, van Middlecoop M, Assendelft WJJ, de Boer MR van Tulder MW. Benefits and harms of spinal manipulative therapy for the treatment of chronic low back pain: systematic review and meta-analysis of randomised controlled trials. BMJ 2019;364:l689 [full text]
- Ernst E; Chiropractic manipulation for non-spinal pain–a systematic review. N Z Med J. 2003 Aug 8;116(1179):U539.
This website is now completed, although I shall continue to do updates. The following list shows the sections or chapters. Just click on the topic in blue to go to that part of the site.