Flaccid Paralysis Vs Spastic Paralysis

Flaccid Paralysis describes a condition in which people experience limp, floppy muscles that lack firmness, due to lack of activity in these muscles. Voluntary control over these muscles has been lost and they are unable to contract. This can result from diseases such a Polio and West Nile Virus as well as  Neuromuscular diseases such as Myasthenia Gravis.

Spastic Paralysis is a term used to describe a condition where people experience spasms that can be accompanied by muscle stiffness. Spasms are spontaneous, uncontrolled, exaggerated muscle contractions that can result in uncontrolled jerky movement. In spastic paralysis the nerves controlling muscle movement are hyperirritable and do not function in a coordinated manner, so that impulses from them cause spasmodic muscle contraction.

Spinal cord injury, such as that produced by inflammatory diseases of nerve tissue, can injure motor neuron fibers in the spine and cause spastic paralysis. Congenital spastic paralysis, or cerebral palsy, is often a result of intrauterine disease or birth injury, or occasionally some inherited nervous system defect.