Medical Definition of TONUS. 1. : tone 2a. 2. : a state of partial contraction that is characteristic of normal muscle, is maintained at least in part by a continuous bombardment of motor impulses originating reflexly, and serves to maintain body postureâcalled also muscle tone; compare clonus.
Neuralgia is the definitive term for nerve pain. Words ending in -algia indicate pain. A closely related word is neuropathy. It indicates an injury, disease, deterioration, defect or other abnormality of the nerve, which usually produces pain, pos...
Sciatica is a pain that runs along the sciatic nerve, a large nerve extending from the lower back and down the back of each leg. Sciatica is a common kind of back pain. Although sciatica can be very painful, it is rare for the disorder to cause permanent nerve damage. Pain in the rear or leg that is worse when sitting.