Periodic Leg Movements

Periodic leg movements are repetitive, involuntary movements of the limbs while a person is asleep.

Most often, the movements involve parts of the legs such as the toes, ankles, knees or hips. The arms can also be involved. These movements last only a few seconds and typically occur every 20 to 40 seconds sporadically throughout the night. They are not the same as the common spasms that many people experience when falling asleep.

Such movements can result in partial or full awakenings from sleep, causing sleep fragmentation, which can lead to daytime fatigue.


Periodic leg movements occur in approximately 4% of adults. The condition occurs more often in middle-aged and older patients, especially females. Periodic leg movements occur in 80-90% of patients with restless leg syndrome,[[link]] but the reverse is not true: Many patients with periodic leg movements do not have restless leg syndrome.

Types of Periodic Leg Movements

Primary Periodic Leg Movements

The condition is called primary period leg movements when:

  • The cause is unknown.
  • Some types of antipsychotic or antidepressant medications or withdrawal from medications may be causing it.
  • It is precipitated by medical conditions including:

Secondary Periodic Leg Movements

The condition is referred to as secondary periodic leg movements when other medications or medical conditions play a role.


In many cases, patients are unaware they have periodic leg movements, and they come to the clinic or their physician with unexplained insomnia or daytime fatigue.

In other cases, a sleep partner observes periodic leg movements.

The only way to obtain a definite diagnosis is to conduct an overnight polysomnogram (PSG) or sleep study, which records limb movements and other body functions during sleep. We may also obtain blood work to test iron levels and rule out other electrolyte abnormalities.


We treat primary periodic leg movements only when the patient also has restless leg syndrome, insomnia or daytime fatigue. Treatment is the same as the treatment for restless leg syndrome.

For secondary periodic leg movements, treating the underlying condition may be helpful when possible.

Next Steps

Please call 734-936-9068 to schedule a clinic visit.

We will need a referral from your physician before your appointment. We look forward to helping you resolve your sleep issues.