The DSM-5, Diagnostic Criteria and a new name to replace  Restless Legs Syndrome / Period Limb Movement Disorder

Please see the parent page ../ for the context of the material below.

Page established 2011-10-22.  Latest substantial update 2011-11-16.  Latest minor update 2013-04-07.

This material is directed at psychologists and other health-care professionals who are already familiar with Restless Legs Syndrome (RLS) and Periodic Limb Movement Disorder/Syndrome (PLMD/PLMS) also potentially known as Periodic Limb Movements in Sleep (PLMS) or Period Limb Movements of Wakefulness (PLMW).  I will refer to all these as "PLMD". 

It is also directed at those who are responsible for the DSM-5. and plan to change the name of "Restless Legs Syndrome" to "Willis-Ekbom Disease", which clashes with the plan to continue the use of "Restless Legs Syndrome" in the DSM-5.  I argue that this condition should not have its own diagnostic category in the DSM, since it is not a mental / psychiatric disorder.  It is a movement disorder, with all the pathology occurring in the spinal cord.  It is also a sleep disorder, in that it invariably disrupts sleep.  However, it is not primarily a sleep disorder, since the symptoms and pathological mechanisms do not directly involve sleep mechanisms.  I argue that this condition should be referred to in the DSM as a leading cause of insomnia.

I propose these two diagnostic criteria RLS and PLMD be replaced by a term for a condition whose etiology is now understandable:

Restless Limbs Sensorimotor Disorder (RLSD)

Quick update 7th April 2013:

The DSM-5 is due for release in May.  According to this authoritative article (2013-03-15):

one of the new diagnoses in the DSM-5 is indeed "Restless Legs Syndrome". 

On 2013-02-28 the US-based Restless Legs Syndrome (RLS) Foundation began doing business as the Willis-Ekbom Disease (WED) Foundation.  The site still exists and appears to have the same contents as the new site: .

The other organization which is changing its terminology is the International Restless Legs Study Group:

However, the change they propose is less absolute: "a gradual transition to the use of the name Willis-Ekbom Disease in addition to Restless Legs Syndrome for those countries or situations where the name Restless Legs Syndrome has become a problem."

I am glad to see that the page you are reading now is Google's top result for a search for "Restless Legs" "DSM-5".

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© 2011 Robin Whittle  Melbourne Australia 


>>> Introduction The RLS -> Willis-Ekbom Disease name change, and the DSM-5's RLS.
>>> Amalgamation under Restless Limbs Sensorimotor Disorder (RLSD) 
>>> Should RLS/PLMD/RLSD have its own diagnostic category in the DSM-5?
>>> Update history



It is widely recognized that the conditions targeted by the separate diagnostic categories of RLS and PLMS both result from the same underlying pathology.  The same treatments are used for sufferers whose symptoms meet either or both diagnostic categories.  For those sufferers with both sets of symptoms, a successful treatment invariably reduces or eliminates both sets of symptoms.

Officially, and in practice (in October 2011, for most researchers and practitioners) the etiology of both RLS and PLMD is unknown.  As far as I know, no comprehensive - or even tentative and incomplete - etiological hypothesis for RLS/PLMD has published in a peer-reviewed journal.

On 1 September 2011 I sent a 32 page document to about 25 RLS researchers, outlining my new observations and etiological hypotheses.  I am confident that this will be be basis for a widely accepted etiology of the underlying condition.  Please let me know if you would like a copy of this document.  It is NOT for publication.  In 2012 I plan to create a revised version which will be publicly available on this site.  There will also be a section of this site devoted to researchers and clinicians, including independent researchers such as myself who got into the field due to our concern about our own symptoms, or in my case, my wife Tina's symptoms.

A brief outline of my etiological hypotheses is at the parent page:  ../#summary .

A summary of my new observations and etiological hypotheses, specifically for medical specialists and researchers is:  ../briefsumm/ .

RLS/PLMD has been researched for decades, with hundreds of papers and numerous expensive drug and genetic trials, with no significant progress towards understanding the etiology.  Many researchers still believe the pathology is in the brain, and the Restless Legs Syndrome Foundation encourages people do donate their brains to their brain bank, to further RLS research.  Yet there's plenty of evidence that the pathology is entirely in the spinal cord.  There's no widely accepted evidence of causative pathology in the brain or the limbs.  (Unless perhaps vascular problems in the legs directly disrupts the circulatory system in a way which reduces tyrosine supply to the lumbar spinal cord.)

In mid-November 2011, I am still awaiting feedback from the RLS researchers.  (In April 2013 I still haven't received any feedback.) They are probably taking a while to read my material, and wondering how to respond to someone from outside their field - a non-academic from Australia.

I am confident that that with refinement and further research, a full etiological theory will emerge along the lines I suggest. 

I argue that the condition is not a disease and that the two existing diagnostic criteria should be replaced by the new name:  Restless Limbs Sensorimotor Disorder.  Below is the section of my 32 page document where I argue for this.  That piece was directed to RLS specialists who are already aware of the difficulties with the current name, not least that it only concerns the legs, when in fact symptoms are common in the arms, and sometimes the torso.  At least one peer-reviewed journal article has reported similar symptoms in the face. (To do: find the reference.)

The Restless Legs Foundation ( and the International Restless Legs Study Group ( have jointly decided to rename the condition "Willis-Ekbom Disease":  (June 2011.)

However, overshadowing this is something far more significant.  The DSM-IV did not specifically mention RLS.  The new DSM-5, is planned to include a new diagnostic category within the sleep disorders section:  "Restless Legs Syndrome":

In order to give feedback on these changes, one must get a user account. I did this, but on 2011-10-24 I can't see where to log in.  The reason seems to be that there were two or more comment periods, which have now closed.  According to: the last comment period ended on 2011-06-15.  Perhaps there will be further opportunity to comment, since the final version is currently scheduled for release in May 2013 (according to the overview).

The above page contains two alternative texts for the proposed diagnostic criteria. Both alternatives involve mentioning just the leg symptoms, but there is additional text (apparently not footnotes, but I guess after the main text) which mentions "the arms or other parts of the body".

Even if there was no proposed or agreed etiological theory, I would propose the amalgamation under Restless Legs Sensorimotor Disorder.

I am sure this is not a disease.  The problems arise from a part of the human "design" which only recently evolved (the last few million years, since we became bipedal and developed foot arches).  There may be some genetic variations which make it worse, and obviously low levels of iron in neurons is a significant contributing factor.  Pregnancy, spinal injury, vascular problems and end-stage renal disease also contribute to or precipitate symptoms.  However, there's no cancer, no infection, no degeneration - and nothing is wrong with the brain or legs.  There's usually nothing wrong with the spinal cord either - but this is where things go wrong, usually for reasons which can be corrected with dietary changes and other non-drug approaches.

Whether or not this condition is regarded as a "disease" or a "disorder", I argue strongly against using family names for any pathological condition.  People in general, and children in particular, need to be able to go through life without their given or family names instantly evoking thoughts of pathological disease.

Consider the fate of two children: Amelia Alexander and Amelia Alzheimer.  Which child is going to cop more flak in the schoolyard?  Which child is going to be burdened with regret about a particular, unchosen, inseparable, part of their self?

Likewise for those whose family names are Willis or Ekbom if the proposed name change is accepted.

Below I argue for the adoption of Restless Legs Sensorimotor Disorder (RLSD), to encompass not just RLS and PLMD, but also the less intense but surely more prevalent disturbances of sleep due to the same processes, which are currently classed as insomnia or some other sleep disturbance of unknown cause.

I haven't devised what I think would be a good diagnostic criteria for RLSD.  If and when I do, I will add it to this page. 

 - Robin Whittle  


Amalgamation under "Restless Limbs Sensorimotor Disorder"

Here is what I wrote in my 32 page document of 1 September 2011, as sent to about 25 RLS researchers:

Amalgamation under "Restless Limbs Sensorimotor Disorder"

The term "Restless Legs Syndrome" is widely recognized as being inadequate, if only because the same symptoms frequently occur in the arms and torso. argues against the term and for the change to "Willis-Ekbom Disease" in this document from 2011-06-23:

I understand that this name, like the choice earlier in 2010 of "Ekbom Disease", has been decided in collaboration with the International Restless Legs Study Group.

Contrary to's arguments, I think "restless" is a perfectly good description of this pathological state of the limbs, since when we are not walking or running, we shouldn't have an urge to move them, and they shouldn't move of their own accord.

It is vital that we recognize the diagnostic categories of RLS and PLMD as arising from a common pathology.  I hope that my observations and hypotheses will be widely discussed and will be improved and accepted as the basis for a common etiology for the conditions described by these two diagnostic categories.  Even if researchers and clinicians couldn't agree on a single etiology, if there is to be a name change now, I argue that it should be to an encompassing term which is descriptive of the symptoms.

"RLSD" closely resembles "RLS".  People will use "Restless Limbs" as shorthand,  just as they now use "Restless Legs".

There's no doubt this is a "sensorimotor disorder" - it has both sensory and motor symptoms.  "Sensorimotor disorder" is frequently used in the introductions of RLS papers to describe RLS.  Google finds 6000+ pages for "sensorimotor disorder" and "RLS".

While "Limbs" doesn't encompass the torso, I think this is acceptable since it would be rare for anyone to have these symptoms in their torso alone. 

"Restless" is a good description of both the sensation and the involuntary movements.

I think it is vital to have a highly descriptive name for any medical condition, because it is easy to remember and to enable sufferers to recognize their condition by its name alone.

The terms "Ekbom Disease" or "Willis-Ekbom Disease" have none of these benefits.  Already, there is confusion with the other disorder named after Karl-Axel Ekbom.  This site: states "The Ekbom Syndrome Association is dedicated to helping people who suffer with Restless Legs Syndrome, also known as Ekbom Syndrome."

Yet, "Ekbom Syndrome" and "Wittmaack-Ekbom Syndrome" have a long history of being used to refer to Delusional Parasitosis: .

"Syndrome", "disorder" and "disease" are close enough in many people's minds as not to be properly distinguished - as with the people adopting "Ekbom Syndrome" instead of "Ekbom Disease" or "Willis-Ekbom Disease".

"Willis-Ekbom" could be mistaken for "Wittmaack-Ekbom".

Furthermore, the perception of parasitic insects crawling under the skin (Delusional Parasitosis) is hard to distinguish from some of the descriptions given by RLS sufferers, including: "creepy-crawlies", "heebie-jeebies" and "like ants crawling under my skin".

I argue that this condition is not really a "disease", any more than the systematic weakness of the human lower back is a disease.  RLSD is primarily a product of a recently evolved reflex response not having the support from blood supply and the CSF circulatory/diffusional system which is required to provide sufficient tyrosine 24 hours a day to some evolutionarily novel dopaminergic output terminals in the spinal cord.  I think that for sufferers who have had the symptoms from an early age, the most significant factor contributing to the problems is probably a different genetic design for iron transport, which in high-iron diet situations would have given their ancestors a decisive advantage.
Causes of what might be termed "secondary RLSD" - pregnancy, iron deficiency, end-stage renal disease and venous problems in the legs (which I assume affects circulation in general, reducing flows to the spinal cord) - are simply adding to the factors which contribute to the potentially inadequate design of the supraspinal inhibition system for the foot-arch protective reflex circuits.  The outcome and the underlying causes hardly seem worthy of the term "disease".  (Towards the end of this document I consider the "primary" and "secondary" RLSD, and suggest that these distinctions may not be valid.)

The disorder and its underlying mechanisms are not genetic, cancerous, auto-immune, psychosomatic, infectious or degenerative - they are just an aspect of human physiology and neurology which doesn't work very well.  Furthermore, the symptoms are transient and can change within seconds and minutes as conditions  are altered.  I believe they could be induced in almost anyone if they were short of tyrosine and/or iron, were immobile for a few hours, and/or if their CSF had higher than normal levels of dopamine receptor antagonists and/or opioid receptor antagonists.

Finally, I argue against naming any pathological condition with one or more family names.  There are unknown hundreds of thousands of people whose family name is either Willis or Ekbom.  The currently proposed name-change would place an unreasonable burden on these people and their descendents - especially their children.  When introducing themselves, no-one should have to face a situation where the first word which comes into people's mind at the mention of their family name is disease.


Should RLS / RLSD have its own diagnostic category in the DSM-5?

On 23 October 2011, Tina pointed out that this condition may not belong in the DSM at all.  I agree, since it is not a psychiatric disorder.  

I think RLS/PLMD/RLSD is a neurological disorder which should be referred to in the DSM-5 as a leading cause of insomnia and that it should not have its own category in the DSM, since it is not a mental / psychiatric disorder.

Here's why:

RLS/PLMD/RLSD is not inherently a sleep disorder, since its mechanisms and effects are much the same when awake.  A sleeping person may not consciously perceive the RLS sensations, or the effects of limb movements.  However, the movements occur pretty much the same, or identically, when awake as when asleep.  Sleep itself does not alter the pathological processes, though perhaps REM sleep may reduce or eliminate the movements via its global inhibition of all lower motor neurons except those of the eyes.

Nonetheless, RLS/PLMD/RLSD typically does disrupt sleep.  I think few people would suffer from it only when they are awake.  Those who seem to sleep through their PLMs may seem to be unaffected, but I am sure it does affect their sleep.  There is research (to do, find the references) that PLMs in sleep are a cause of high blood pressure.  This presumably degrades sleep and has serious long-term consequences for heart disease.  Those who are lucky enough to sleep through their PLMs are likely to be disturbing their bed-partner.

I am arguing that the future RLSD diagnostic criteria be extended beyond a union of the RLS and PLMD diagnostic criteria (and there is debate about how reliable or appropriate the RLS criteria are) to also encompass symptoms which are not consciously perceived as RLS discomfort, twitchiness, agitation etc., and which may not involve PLMs, but which nonetheless degrade sleep.  Therefore, I am arguing that the diagnostic criteria for "Insomnia" include a section which identifies sleep disturbances due to the RLSD pathologies, as distinct from other underlying causes - even if the sufferer or their bed-partner does not consciously perceive that anything is wrong. 

The RLSD pathologies are: insufficient dopaminergic receptor activation in the relevant spinal cord synapses, perhaps accompanied or exacerbated by insufficient opioid receptor activation in the relevant (presumably entirely spinal cord) synapses.  There are various causes of these, involving iron, tyrosine, circulation, vibration, opioid receptor antagonists, dopamine receptor antagonists, spinal injury, kidney failure etc.  Hence the need for a 32 page document!

The DSM is a diagnostic manual of mental disorder, produced by psychiatrists, for use by psychiatrists, psychologists, psychotherapists and many other types of clinician in many countries, including GPs (General Practitioners - family doctors) and nurses.

Two rather similar definitions of the scope of the DSM-5 are being considered.  This page, "Definition of a Mental Disorder", contains the two alternatives and in separate tabbed pages, the rationale and the existing DSM-IV text:

There has never been convincing evidence that RLS/PLMD/RLSD pathology is in the brain.  I believe the etiological hypotheses I have presented will be the basis for a well researched and widely accepted etiological theory - and these hypotheses concern the spinal cord, not the brain or brain-stem.  The fact that spinal injury can lead immediately to RLS/PLMD/RLSD symptoms which persist indefinitely seems to indicate that the pathology need not be in the brain - and therefore might never be in the brain.

RLS/PLMD/RLSD is typically a movement disorder, unless the only symptom is disturbed sensations - that is, there are never any involuntary movements.  (However, this is unlikely to be the case, since the sensations effectively force the person to move their limbs consciously, contrary to their actual desires.)  Since the disorder occurs with spinal nociceptive systems which have a dual role - reporting to the brain and driving withdrawal actions in muscles - I think it would be unrealistic to define it as not being a movement disorder, for the small subset of people who may not in fact experience involuntary movements in sleep or when awake.  I am sure that if anyone with this condition had the sole of their foot touched lightly with a pencil-tip, they would have involuntary movements!  So if we agree that the concept of movement disorders covers involuntary movements in response to stimuli which would normally not elicit movement, then RLS/PLMD/RLSD is certainly a movement disorder. 

It is hard to imagine the pathological processes not degrading the sufferer's sleep, or the sleep of the sufferer's bed-partner.  So RLS/PLMS/RLSD is a movement disorder which invariably disrupts sleep.

It is a disorder of the central nervous system - of the spinal cord, not the brain.

Is Sleep Medicine within the realm of psychiatry?  I think it is.  The American Board of Medical Specialties lists the Sleep Medicine Subspecialty Certificate within the following General Certificates:
Each of these fields of medicine has its own regulatory board, for instance the American Board of Psychiatry and Neurology.  The DSM is the product of the American Psychiatric Association.  The American Neurological Association is separate, though the two professions are regulated by the same board.

I think that while this condition:
it still has a place in the DSM because:
However, this condition is an oddball in the DSM, since it is not by any ordinary definition a mental condition.  Therefore, it is not a "psychiatric" condition.

Parkinson's Disease is a diagnostic category in the DSM-5, though there are categories:

for Mild or Major Neurocognitive Disorders associated with a variety of implicitly non-mental pathologies, including Parkinson's Disease, HIV Infection, Vascular Disease, Prion Disease and Alzheimer's Disease.  Many conditions affect sleep, including many movement disorders.  These movement disorders do not have their own diagnostic categories within the DSM-5, but they are referred to in the DSM-5.

I believe that the underlying disorder which gives rise to RLS and PLMD symptoms, by whatever name, should be referred to in the DSM-5 due to its high prevalence, its impact on sleep and its general impact on health.  For instance something along the lines by which these two revisions refer to Parkinson's Disease:

S 18 Mild Neurocognitive Disorder Associated with Parkinson's Disease

S 30 Major Neurocognitive Disorder Associated with Parkinson's Disease

I argue that this RLS/PLMD/RLSD disorder should not have its own diagnostic category in the DSM-5, because it is not a psychiatric disorder. Yet this is a planned revision for the DSM-5:

M 11 Restless Legs Syndrome

I understand that RLS sufferers are typically referred to neurologists or sleep specialists, rather than psychiatrists.  However, considering the huge number of people who suffer from the condition, I think the best way of handling it is a combination of well-informed sufferers and carers and well-informed GPs and nurses.  

RLS/PLMS/RLSD is highly amenable to non-drug interventions, though this is not widely recognized at present: percussive or vibratory spinal massage, oral tyrosine and partial topical anesthesia of the skin of the arches of the feet (we are experimenting with this at present, with clove oil).  Once everyone understands the etiology, they will be able to make most of the problems go away with correct nutrition, including avoiding coffee and ideally caffeine.  The remaining difficulties will be highly amenable to non-drug interventions.  Still, a few people may require prescription drugs, but I expect this will be a small fraction of the numbers who are currently prescribed dopamine- and opioid-receptor agonists.

Many of those who continue to suffer significantly from it once they do this (or if they choose to keep using coffee and caffeine) should probably take iron supplements.  They could do this themselves, but it really should be done under the supervision of their GP. 

I think psychiatrists would not be involved at all, except in their capacity as a general medical doctor.  I think neurologists would only be involved if the usual measures failed to reduce the problem acceptably, which the might for some people due to spinal injury, unusual genetics or a developmental abnormality.  (I don't know of any developmental abnormalities which cause RLSD, but the possibility can't be ruled out.)


Update history

Page established, with "Introduction" and "Amalgamation under Restless Limbs Sensory Motor Disorder".

Added a section regarding the DSM-5.

Expanded and clarified the DSM-5 section with links to the proposed revision for an RLS diagnostic category, and links to two categories which refer to another movement disorder: Parkinson's Disease.

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Contact details and copyright information: ../../contact/
© 2011 Robin Whittle  Melbourne Australia