Rhythmic Movement Disorder - Diagnosis

Diagnosis

Diagnosis of Rhythmic Movement Disorder is done on an exclusionary basis in which other closely related movement disorders are systematically ruled out. Because of this, a thorough clinical evaluation is necessary. Often, impairments are not severe enough to warrant this process and so RMD is not often diagnosed unless there are extremely interfering or disabling symptoms. Many patients do not seek treatment for RMD directly and most seek professional help to alleviate sleep-affecting symptoms. To compound the issue, many sufferers are often misdiagnosed as having Restless Legs Syndrome or sleep apnea or some combination of the two. Rhythmic Movement Disorder differs from Restless Legs Syndrome in that RMD involves involuntary contractions of muscles with no urge or uncomfortable sensation to provoke such movement. Additionally, 80-90% of Restless Legs Syndrome sufferers show periodic limb movements as observed on a polysomnogram, which are not common in RMD patients. Rhythmic Movement Disorder can also have symptoms that overlap with epilepsy. However, use of a polysomnogram can help distinguish one disorder from the other as RMD involves movements in both REM and NREM sleep, which is unusual for seizures . Additionally, patients can usually stop the movements upon request, unlike the movements observed in epilepsy. Other movement disorders like Parkinson’s Disease, Huntington’s Disease, ataxia, and dystonia differ from RMD in that they occur primarily during wakefulness and reduced sleep, whereas RMD episodes occur in or around sleep .