Sleep - Periodic Limb Movements

Periodic Limb Movements in Sleep (PLMD) is a symptom that is commonly associated with another type of sleep disorder which is known as Restless Leg Syndrome (RLS). However, while similar, PLMS is a separate condition and RLS is not always present at the same time.

Although PLMD does not seem to cause or aggravate any other medical conditions itself, the frequent limb movements can obviously cause a disruption in a person's sleep. This sleep disruption can lead to significant insomnia, or an insomnia like condition, which can have its own adverse affects on health, attention, and activities. It is for this reason that PLMS is considered to be a sleep disorder.

There are not many symptoms of PLMD, but, if there's a good side, at least they're obvious.

As the name implies, periodic limb movements, the lower limbs, okay, legs, of individuals with this disorder move, not just once in a while, but, repetitively, for varying periods of time. These movements, which are either sudden jerks, or twitches, or a flexing of the foot upwards, occur while the individual is asleep. These episodes can last just a few seconds, a minute or two, or they can go on for many hours. However, once an episode stops, it typically takes less than a minute for the episode to repeat.

An individual with PLMD may also have symptoms of Restless Leg Syndrome (RLS) which also consists of awkward feelings in the limbs. People with RLS describe these feelings as a crawling, or prickly, or tingling sensation in the legs and, sometimes even in the arms. There generally aren't any other noticeable symptoms, although medical measuring machines would show some. Since the leg movements happen during sleep, you may not even be aware of this condition. Obviously, it is usually the bed partner who first becomes aware of the condition.

So far, there seems to be no single common cause for PLMD's although some medications and conditions may contribute to the condition. Despite that, it seems fairly certain that the movements have something to do with the way the individual's central nervous system functions. It can be secondary, that is, meaning that it may be the result of some other condition such as diabetes, sleep apnea, narcolepsy or anemia.

When someone experiences these types of movements during sleep, and if they also have symptoms of Restless Leg Syndrome, a diagnosis of PLMD is generally suspected. If an individual is complaining of constant fatigue for which no other cause has been identified, a doctor might have cause to suspect PLMD. To confirm such a diagnosis, a doctor will usually have the sufferer spend a night in a sleep center where the patient's sleeping patterns can be closely monitored.

Since it's root cause is not known, it is difficult to prescribe a treatment for PLMD. Some patients can be treated with medications such as Benzodiazepines. These can help the victim ot get a better night's sleep. There are also medications that can be taken to help control the movements themselves, including anticonvulsive agents, dopaminergic and GABA agonists.