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.
What is an Annular Tear? Between the vertebrae of the spinal column rest discs made of cartilage, which cushion bones and facilitate movement. Surrounding each intervertebral disc, a tough, shock-absorbing layer known as the annulus protects the discâs vulnerable interior.