Disc herniation is a common term used to describe the disruption of the intervertebral disc.
A disc herniation model is helpful is the explanation of how the nucleus pushes out radially through the outer walls of the disc.
Recently, lumbar disc terminology has been updated as there has been some confusion in the nomenclature in discussing this common condition. To read the latest in terminology, visit here as the publication is open access and in full text.
Herniation is a general term and not specific enough when describing the type of herniation. It is currently described as a local or focal displacement of disc material beyond the limits of the intervertebral disc space.
The material can be any material of the disc including:
- fragmented apophyseal bone
- annular material
- any combination
If a disc’s material extends beyond the boundaries of the apophyseal ring endplates in a circumferential fashion, then the term used to describe this is a ‘bulging’ disc and not a herniation.
Disc herniation can be classified into the shape of displacement of material and they are classified into:
- protrusion (if the base of the material is larger than the material protruding)
- extrusion ( when the material is smaller at the base)
- sequestrated (material has moved independently away from the disc)
- intravertebral herniation (where the material has moved into the endplate)
There is also another category indicating whether the disc is contained or non-contained. Contained indicates the the material has not ‘broken through’ the posterior logitudinal ligament, whereas, a non-contained has.
Annular tears, which was a term used to describe the damaged annular wall, is now described as a annular fissure. Fissures are a better descriptor because tears indicates a traumatic event which in most cases it is difficult to tell if the damage is traumatic or as a result of ongoing poor posture, for example.
Dynamic Disc Models strive to remain current with terminology so patients can understand the mechanisms of their back pain and manage accordingly. An accurate disc herniation model can assist in the patient-doctor team to improve outcomes.