Functional Movement Disorder (FMD) happens when you experience involuntary movements within the body. • FMD is often prevalent within individuals who also have TS, however this often goes undiagnosed due to the similarities of the two. • Both TS & FMD have the kinematics of voluntary movements (although TS movements can appear more 'normal').
They both worsen with attention, are suggestable and distractible.
They both also have common co-occuring conditions such as mood and anxiety disorders. • However they are different due to the following:
FMD's onset is usually in adulthood, these symptoms come on suddenly and in full force, symptoms usually are the same. Its common for tics to appear after a psychological or physical event. (Note: This does not rule out children - my son has FMD too age 11 at diagnosis)
FMD movements are completely unwilled and involuntary unlike TS movements which although unwanted, there is some element of control over them (suppressible)
FMD rarely respond to anti-tic medication
FMD movements rarely affect the head, its more common to affect the body and limbs.
FMD movements are not subject to a premonitory urge
As you can see the difference really is very small.
Below is a list of different movement disorders from the Mayo Clinic website. They state here that " Functional movement disorder may resemble any of the movement disorders, but is not due to neurological disease."
-Ataxia. This movement disorder affects the part of the brain that controls coordinated movement (cerebellum). Ataxia may cause uncoordinated or clumsy balance, speech or limb movements, and other symptoms.
-Cervical dystonia. This condition causes long-lasting contractions (spasms) or intermittent contractions of the neck muscles, causing the neck to turn in different ways.
-Chorea. Chorea is characterized by repetitive, brief, irregular, somewhat rapid, involuntary movements that typically involve the face, mouth, trunk and limbs.
-Dystonia. This condition involves sustained involuntary muscle contractions with twisting, repetitive movements. Dystonia may affect the entire body (generalized dystonia) or one part of the body (focal dystonia).
-Functional movement disorder. This condition may resemble any of the movement disorders, but is not due to neurological disease.
-Huntington's disease. This is an inherited progressive, neurodegenerative disorder that causes uncontrolled movements (chorea), impaired cognitive abilities and psychiatric conditions.
-Multiple system atrophy. This uncommon, progressive neurological disorder affects many brain systems. Multiple system atrophy causes a movement disorder, such as ataxia or parkinsonism. It can also cause low blood pressure and impaired bladder function.
-Myoclonus. This condition causes lightning-quick jerks of a muscle or a group of muscles.
-Parkinson's disease. This slowly progressive, neurodegenerative disorder causes tremor, stiffness (rigidity), slow decreased movement (bradykinesia) or imbalance. It may also cause other nonmovement symptoms.Parkinsonism.
-Parkinsonism describes a group of conditions that has symptoms similar to those of Parkinson's disease.
-Progressive supranuclear palsy. This is a rare neurological disorder that causes problems with walking, balance and eye movements. It may resemble Parkinson's disease but is a distinct condition.
-Restless legs syndrome. This movement disorder causes unpleasant, abnormal feelings in the legs while relaxing or lying down, often relieved by movement.
-Tardive dyskinesia. This neurological condition is caused by long-term use of certain drugs used to treat psychiatric conditions (neuroleptic drugs). Tardive dyskinesia causes repetitive and involuntary movements such as grimacing, eye blinking and other movements.
-Tourette syndrome. This is a neurological condition that starts between childhood and teenage years and is associated with repetitive movements (motor tics) and vocal sounds (vocal tics).
-Tremor. This movement disorder causes involuntary rhythmic shaking of parts of the body, such as the hands, head or other parts of the body. The most common type is essential tremor.
-Wilson's disease. This is a rare inherited disorder that causes excessive amounts of copper to build up in the body, causing neurological problems