Restless Leg Syndrome and Periodic Limb Movement Disorder

Restless leg syndrome and periodic limb movement disorder have similar symptoms and often occur together, but they are distinct conditions that require different tests and sometimes different treatments.

Restless Leg Syndrome
RLS causes uncomfortable, tingling, and painful sensations -- usually in your legs -- that make you feel like you need to move. Movement usually relieves the sensations momentarily, but they quickly return. Symptoms tend to worsen in the evening around bedtime and often lead to insomnia. RLS can be genetic, but it can also be caused by sleep apnea, kidney disease or injury, or low iron stores called ferritin. RLS can also be related to peripheral neuropathy. 

Periodic Limb Movement Disorder
Sometimes called periodic limb movements of sleep, this condition causes your legs or arms to move frequently during sleep. PLMD can cause daytime drowsiness, but it often goes undetected because you aren’t aware of the movements while you’re asleep. RLS can cause PLMD.

Your doctor will perform a physical exam and ask questions about your medical history and symptoms. They may order bloodwork to check your iron levels.

Sleep Study
Your doctor may suggest you undergo an overnight sleep study if:

• You have daytime fatigue that is otherwise unexplained.
• You regularly notice that your bedding is very disheveled in the morning. 
• A bed partner reports that you move around a lot during sleep. 

During a sleep study, leads placed on your limbs will measure your movements as you sleep. At least 15 limb movements per hour generally indicates you have PLMD. A sleep study can also help identify whether another sleep disorder like sleep apnea might be causing your limb movements or making them worse. 

We Treat the Full Spectrum of Sleep Problems
Restless leg syndrome and periodic limb movement disorder may or not be related. Other sleep disorders can cause or be caused by RLS or PLMD. Our sleep medicine specialists distinguish between these disorders, help identify their root causes, and minimize downstream effects.

We Treat Difficult Cases
People often come to Duke with hard-to-treat cases of RLS and other sleep disorders. Our sleep experts work together and collaborate with other specialists to create successful, personalized treatment plans when other treatments have failed.