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.
Cervical Annular Tear. A cervical annular tear occurs with a disc herniation. The annular tear is a tearing of the disc external surface that may occur with the aging process or with injury. The annulus may thin or bulge or weaken to the point that disc material may extrude into the spinal canal.