Periodic Limb Movement 

Disorder & Restless Legs


Restless legs syndrome (RLS) is a neurological disorder characterized by a strong — nearly irresistible — urge to move the legs. It is categorized as a sensorimotor disorder because it involves nerves that transmit sensations and those that command the muscles to move. You may experience involuntary jerking or twitching movements of the legs while sitting or lying awake, an uncontrollable urge and uncomfortable sensation in the legs (or possibly arms), and sometimes a creepy, crawly feeling that occurs more often in the evening. This continuous need to stretch or move can cause insomnia or delay sleep onset, which in turn leads to excessive daytime sleepiness and the inability to function optimally during the day. Ultimately, the irritable sensations can lead to anxiety and depression.

Periodic Limb Movement Disorder
Periodic limb movement disorder (PLMD) is similar to RLS, but occurs while a person is asleep. The movements include anything from an extension of the big toe to a flexing of the knee or hip. The intervals between each movement are usually regular (20 to 40 seconds), and these movements usually cluster at the beginning of the night. A certain number of limb movements per night are considered normal. For the diagnosis of PMLD, an involuntary movement of a section of the limbs must occur at least four times in a row while you are asleep and you must have symptoms of RLS.

Our experienced sleep disorders specialists at Houston Methodist employ a multidisciplinary approach to diagnose and treat RLS and PLMD.

How Common Are RLS and PLMD?
Eighty percent of the people who have RLS may also have symptoms characteristic of PLMD to some extent. However, many people with PLMD say that they do not have symptoms of RLS. It is thought that RLS affects anywhere from 5 to 15 percent of the population at some point in their lives. RLS is more common in older people, but can occur in both men and women at any age.

PLMD is rare in people under the age of 30 and only affects a very small percentage of the population between ages 30 and 50. This increases to one third of the population 50 years and older, and nearly half of the people over age 65.

Treatment Options for RLS and PLMD
Our team of sleep specialists can help diagnose and offer treatment options unique to each patient’s condition.

Some people with RLS get relief from home remedies, such as a hot bath, heat and ice packs, massaging the affected area, pain relievers, regular exercise and the elimination of caffeine and tobacco.

When these methods do not provide adequate relief, medication may be effective. Because everyone responds to medication differently, your doctor may try several different drugs over a period of time to see which is most effective.

Some people with periodic limb movement disorder (PLMD) are able to sleep through the leg movements without any arousals, so no treatment is needed. However, many PLMD patients experience repetitive "micro-arousals" throughout the night, preventing them from getting restorative sleep, and therefore may need to be treated to optimize sleep and functioning while awake . If treatment is needed, the medications are generally the same as those used to treat RLS.


Our physicians at Houston Methodist specialize in evaluating and treating restless legs syndrome and periodic limb movement at the following convenient locations.