What is (are) spastic paraplegia type 4 ?
Spastic paraplegia type 4 is part of a group of genetic disorders known as hereditary spastic paraplegias. These disorders are characterized by progressive muscle stiffness (spasticity) and the development of paralysis of the lower limbs (paraplegia). Hereditary spastic paraplegias are divided into two types: pure and complex. The pure types involve only the lower limbs, whereas the complex types also involve the upper limbs (to a lesser degree) and the nervous system. Spastic paraplegia type 4 is a pure hereditary spastic paraplegia.  Like all hereditary spastic paraplegias, spastic paraplegia type 4 involves spasticity of the leg muscles and muscle weakness. People with this condition can also experience exaggerated reflexes (hyperreflexia), ankle spasms, high-arched feet (pes cavus), and reduced bladder control. Spastic paraplegia type 4 generally affects nerve and muscle function in the lower half of the body only.