Define nadir. nadir synonyms, nadir pronunciation, nadir translation, English dictionary definition of nadir. n. 1. Astronomy A point on the celestial sphere directly below the observer, diametrically opposite the zenith. 2. The lowest point: the nadir of their...
Annular tear â definition and causes. By Michael Perry, M.D. An annular tear is one of the most common degenerative spine conditions that develop with the natural aging process of the spine. In fact, many people over the age of 50 have an annular tear and never know it.
Annular fissure is a type of discogenic condition that affects the spine. It usually occurs when the fibers that make up the tough, outer covering of the intervertebral disc (called the annulus fibrosus ) either break or separate. Annular fissure is also called annular tear, although there are differences between the two terms.