Periodic limb movements Disorder (PLMD)
Periodic limb movements in sleep are repetitive movements, most typically in the lower limbs, that occur about every 20-40 seconds. If you have PLMD, or sleep with someone who has PLMD, you may recognize these movements as brief muscle twitches, jerking movements or an upward flexing of the feet. They cluster into episodes lasting anywhere from a few minutes to several hours.
The exact cause of PLMD is still unknown. Scientists believe that the underlying mechanisms probably involve factors in the nervous system, although studies have not revealed any consistent abnormalities. PLMD is not considered medically serious. It can, however, be implicated as a contributing factor in chronic insomnia and/or daytime fatigue because they may cause awakenings during the night. Occasionally, PLMD may be an indicator of a serious medical condition such as kidney disease, diabetes or anaemia.
SYMPTOMS:
Individuals with PLMD may also experience Restless Leg Syndrome (RLS), an irritation or uncomfortable sensation in the calves or thighs, as they attempt to fall asleep or when they awaken during the night. Walking or stretching may relieve the sensations, at least temporarily. However, research also shows that many individuals have PLMD without experiencing any symptoms at all. It’s not unusual for the bed partner to be the one who’s most aware of the movements, since they may disturb his/her sleep.
TREATMENT:
A number of medications have been shown to be effective in treating PLMD, but treatment is only necessary when PLMD are accompanied by restless legs (RLS), insomnia or daytime fatigue.
COPING:
Seek professional medical advice. You may wish to begin by consulting your family physician or by making an appointment for an evaluation at an accredited sleep disorders centre in your area.