Repetitive Arm and Hand Movements (Complex Motor Stereotypy) in a Six-Year Boy

Abnormal movements are not uncommon in children. Most of these abnormal movements can be defined by the available criteria. Abnormal movements are easily diagnosed in adults. Most of these abnormal movements are well categorized and diagnosed by the defined characteristics. Sometimes it is difficult to diagnose an unusual movement disorder in children, particularly if it is rare and there are no investigations to prove the diagnosis. Repetitive arm and hand movements (complex motor stereotypy) is one such disorder which is rare and difficult to diagnose unless seen before. In this case report, we described a 6-year-old boy with this disorder, in whom it took 6 years to diagnose.

Definition and Classification of Involuntary Movements

Involuntary movements, also called hyperkinetic movement disorders, are defined as abnormal, unintended movements. They are defined as “abnormal” because not all unintended movements are pathological (reflexive or spontaneous movements also occur but are part of normal function; these include breathing, yawning, blinking, and the like). Involuntary movements can be classified into several categories according to their phenomenological characteristics and then according to the etiology and/or pathophysiology for each kind of involuntary movement. Involuntary movements include tremor, chorea, ballism, athetosis, dystonia, myoclonus, dyskinesia, tics, asterixis, and motor stereotypy. Many of the involuntary movements can occur as side effects of pharmaceutical drugs. Functional or psychogenic involuntary movements are not infrequently encountered.