What is an Annular Tear
An annular tear refers to a tear or damage to the outer layer of a spinal disc (known as the Annulus Fibrosus). An annular tear is sometimes a precursor to a herniated disc,
What is the difference between a herniated disc and a bulging disc?
There are some differences of opinions between doctors.
This is one common statement Herniated disc and bulging disc usually imply the same thing. There is no specific definition for the term herniated disc, bulging or protruded disc.
Here are details from Peter F. Ullrich, Jr., MD
There are many different terms used to describe spinal disc pathology and associated pain, such as “herniated disc”, “pinched nerve”, and “bulging disc”, and all are used differently by doctors.
Unfortunately, there is no agreement in the healthcare field as to the precise definition of any of these terms, and patients are often frustrated when they hear their diagnosis referred to in various terms by different practitioners. Additional terms such as ruptured disc, torn disc (or disc tear), slipped disc, collapsed disc, disc protrusion, disc disease, and black disc often add to a patient's confusion.
Rather than try to reconcile the terminology used to refer to disc problems, it's generally more useful for patients to gain a clear understanding of the precise medical diagnosis, which identifies the actual cause of the patient’s low back pain, leg pain, or other symptoms.
Bulging discs are still contained within the annulus fibrosis. Herniated disc extend outside the annulus.
A herniated disc is a traumatic focused injury to the disc, which results in a portion of the nucleus, or inside material, pushing out into a nerve.
More helpful definitions are the terms contained or non-contained disc herniation. A non-contained disc herniation indicates a disc has herniated material that is no longer connected to the main portion of the disc. A contained disc is a disc herniation that still has connections to the main disc.
This is really a difference of degree. A bulging disc is a smaller protrusion of the central nuclear material still contained by some of the outer annular fibers. A herniated disc is one that has ruptured through the annulus. It is best to give the actual measurements of the protrusions instead of just using the descriptive terms herniated or bulging or even ruptured.
This one is my favorite
Think of your disc as a jelly donut, you can squash down the jelly donut and the jelly never comes out. That is a bulging disc.
A herniated disc is when the jelly actually comes out.