Restless legs syndrome ( RLS ) is a neurological sensorimotor disorder characterized by an irresistible urge to move the limbs ( usually legs ) accompanied by dysaesthesia like creeping crawling , tingling , cramping or aching 

Also known as Willis-Ekbom disease Most patients with RLS also have periodic limb movement of sleep ( PLMS) Exact prevalence is difficult to find
Affects 5-15 % of the general population in the US
 5-10 % in UK
Upto 25 % of patients on dialysis Women affected more commonly Prevalence increases with age Diagnostic criteria as per the International Restless Legs Syndrome
study Group

An urge to move the legs usually but not always accompanied by or felt to be caused by uncomfortable unpleasant sensations in the legs
 The urge to move the legs and any accompanying unpleasant sensation begin or worsen during periods of rest or inactivity such as lying down or sitting
 The urge to move the legs and any accompanying unpleasant sensations are partially or totally relieved by movement , such as walking or stretching , atleast as long as the activity continues
 The urge to move the legs and any accompanying unpleasant sensations during rest or inactivity only occur or are worse in the evening or night than during the day
 The occurrence of the above features are not solely accounted for as symptoms primary to another medical or behavioral condition ( eg myalgia , venous stasis , legs edema , arthritis , leg cramps , positional discomfort , habitual foot tapping )

Primary-Familial pattern Likely autosomal dominant Patients start suffering early , can start in childhood Can progress showy through age secondary-Iron deficiency Pregnancy – 26 % may develop RLS Renal insufficiency Drugs eg 
♦ antidepressants-tricyclics , SSRIs , SNRIs
♦ some antipsychotics and Lithium
♦ some antiepiletics
♦ antihistamines
♦ metoclopramide , prochlorperazine
♦ beta blockers Smoking , obesity , low social status

Aetiology-Not fully understood Abnormalities in the central subcortical dopamine pathways Impaired iron homeostatsis Genetic variants that ↑↑ risk of RLS have been identified and various chromosomes have been implicated

Diagnosis is clinical Examination – including neurological is normal Sleep disturbance is common Ask about family history Check use of nicotine ,alcohol , caffeine Medications Mental health ( ↑ rate of anxiety , depression in people with RLS )   Ferritin ( check in all with suspected RLS ) Renal function FBC TFT Bl glucose B12 , folate Magnesium Consider sleep studies No imaging is currently indicated

Differential diagnosis- Periodic limb movement disorder Akathisia ( inner urge to move all or part of the body without a focal sensory complaint in the limb ) Neuropathy Nocturnal leg cramps Positional discomfort Deep vein thrombosis Intermittent claudication Volitional movements , foot tapping , leg rocking Polyneuropathy

Consider dopamine receptor agonist as pramipexole , ropinirole
 or Rotigotine Anticonvulsants as 
pregabalin
 or gabapentin Off label Levodopa – take when symptoms happen or anticipated Hypnotics-Can be used intermittently during episodes of symptoms Consider in people with significant sleep disturbance Opioids should be stopped first before commencing benzodiazepines Risk of dependency and habituation  opioids-Seem to help RLS symptoms through an unknown mechanism Particularly in painful RLS Risk of opioid dependence Eg codeine phosphate 30-60 mg before bed or Tramadol 50-100 mg before bed or during night Opioid agonists-It is possible that prolonged release
 oxycodone/ naloxone improves RLS symptoms , sleep adequacy , sleep duration and RLS specific
 qoL in patients with RLS who have not 
responded to other treatment

Licensed to use in RLS eg Targinact 

Sleep hygiene Caffeine , alcohol (reduce if in excess) Quit smoking Moderate regular exercise ( benefit has not been studied ) Some patients may benefit with measures before bedtime as
♦ hot or cold bath
♦ whirpool bath
♦ limb massage
♦ vibratory or electrical stimulation of the feet and the toes
 During en episode
♦ walking and stretching the limbs
♦ heat pads or hot bath
♦ mental alertness distraction at times of rest
♦ massaging affected limbs

References
 Practice guideline summary : Treatment of restless legs syndrome in adults Report of the Guideline Development , Dissemination , and Implementation Subcommittee of the American Academy of Neurology December 13 , 2016 :87 (24) European guidelines on management of restless legs syndrome : report of a joint task force by the European Federation of Neurological Societies , the European Neurological Society and the European Sleep Research Society European Journal of Neurology , 2012 , 19 : 1385-1396 CKS NHS Restless legs syndrome Last revised October 2015 Restless Legs Syndrome in Patients with Chronic Kidney Disease Seminars in Nephrology , 2015-07-01 , Volume 35 , Issue 4 , Pages 347-358 BMJ Best Practice Restless legs syndrome Restless Legs Syndrome in Primary Care A Prevalence Study ARCH INTERN MED/VOL ,163 , OCT 2003 Prevalence of restless legs syndrome and associated factors in an otherwise healthy population : result from the Danish Blood Donor Study Sleep Medicine , 2017-08-01 , Volume 36 , Pages 55-61 IRLSSG Diagnostic criteria http://irlssg.org/diagnostic-criteria/