Definition of Movement - unpredictable or jerky:

Jerky body movements is a condition in which uncontrolled, purposeless, rapid motions interrupt normal movement or posture.

Considerations:

Typical movements of chorea (called tics) include facial grimacing, raising and lowering the shoulders, bending and extending the fingers and toes. The condition can affect one or both sides of the body.

These involuntary movements are generally not repetitive and can appear purposeful even though they are involuntary and uncontrollable. A person with chorea may be viewed as jittery or restless.

Common Causes:

There are many possible causes of unpredictable, jerky movements, including Sydenham's chorea, Huntington disease and other rare disorders. Some medical illnesses that can cause chorea include anti-cardiolipin antibody syndrome, systemic lupus erythematosus, polycythemia rubra vera, stroke, thyroid disease, and disorders of calcium, glucose or sodium metabolism.

Some medications such as anti-psychotic drugs, may cause tardive dyskinesia, a movement disorder which may include choreic movements. Rarely, it is inherited in the syndrome called benign hereditary chorea. Some women may develop chorea when pregnant. This is called chorea gravidarum.