I Have What?
The report is in front of you. And it looks dire. Degeneration, bulges, herniations and
annular tears. It sounds terrible!
I am not a radiologist but I have seen a lot of MRI’s and MRI reports over the years.
I have taken many courses and have been privileged enough to work with several
surgeons who read the films with me, so I am going to explain this so a “regular Joe”
can understand it. This is only to help people understand that many of these phrases
and words we use are not quite as scary as they sound.
A normal disc. Normal defines disks that are of proper size, shape and color on
the MRI. They would have a complete hard outer covering and would remain in the
“disc space” with no part of the disc going further than the vertebra above and below
it. To have all “normal discs”, you would probably be very young, not play sports and
have a sedentary job. To be quite honest, after 30, it’s a pretty rare occurrence.
An annular tear or fissure is when there is an opening in the hard outer covering
around the disc. Sometimes it leads to a disc herniation, sometimes it doesn’t. They
generally heal themselves but can often lead to disc degeneration because the
normal fluid in the disc leaks out. The word “fissure” is preferred as it does not
A disc herniation refers to a displacement of disc material beyond the normal
confines of the disc. The herniation can include disc material, cartridge, bone or
annular tissue (or a combination of all of these). The herniation is further
described as either a protrusion or an extrusion.
A protrusion means that the base of the herniation is wider than the rest of it and
the outer fibers of the disc outer covering (annulus) are intact.
An extrusion is when the base (or neck) of the herniation is narrower than the piece
that comes out of the disc. The hard out covering is torn and the piece may hang
down or float up in the spinal canal.
A bulging disc is something no one seems to really agree upon. In 2014 The American
Society of Spine radiology describe it as “annular tissue projecting beyond the
margins of the adjacent vertebral bodies, over more than 90° circumference”.
It also says a circumferential bulge involves the entire disc circumference and
an asymmetric bulge does not involve the entire circumference but more than 90°
of the disc.
In other studies and articles a bulging disc is not considered a form of herniation
but a descriptive term of the shape of the disc contour. Symmetrical bulging disc is
when the whole disc has tissue beyond the edges and an asymmetrical bulging disc
is within the bulging is only noted from one part of the disc still greater than 90°.
Needless to say, every radiologist, according to age, training and vernacular would
describe a bulging disc differently.
The big thing to remember is that no good surgeon “operates on an MRI” which
means we look at the patient and see what their symptomology is and compare it
to the MRI. A person could have 3 herniated discs and no pain or weakness. They
would most likely not require surgery. Someone else could have a small disc that
presses directly on a nerve and not get better over time, or with conservative care,
and would require surgery.
So, calm down. It sounds bad but very often that horrible sounding MRI is normal
for someone of your age and circumstance. Remember a disc herniation or a disc
bulge is only a problem if it is causing one.
- Herzog R, Elgort DR, Flanders AE, Moley PJ. Variability in diagnostic error rates of 10 MRI centers performing lumbar spine MRI examinations on the same patient within a 3-week period. Spine J. 2017 Apr;17(4):554-561. PubMed PMID: 27867079