In medicine, monoplegia is a paralysis of a single limb, usually an arm. It is frequently associated with cerebral palsy. This is the mildest form of cerebral palsy, and individuals with it generally have a good prognosis for later life. It can also be used if just one muscle group or muscle is affected. It is often thought as hemiplegia with much less involvement of the other limb.
A similar condition is monoparesis, in which one limb is very weak, but not completely paralyzed. For more information, see paresis.
A person with monoplegia can be referred to as a monoplegic. Monoplegia of the upper limb is sometimes referred to as brachial monoplegia while that of the lower limb is called crural monoplegia.