Do you know that discs can slip in different ways?
This article is by the chiropractor in Islington at the Angel Wellbeing Clinic and looks at the five or six different possible disc injuries that can occur. These disc injuries can lead to the signs and symptoms of a trapped nerve or pinched nerve.
• Disc bulge
• Disc herniation
• Disc protrusion
• Disc sequestration
Disc pain is a common problem and most back pain has some component of disc pain. The anatomy of the intervertebral disc enables it to support weight and to act as a shock absorber as well as to allow movement but this movement of the disc also leads it susceptible to damage. Discs in the lumbar region are bigger and fatter than in the rest of the spine and with the lumbar region having a lordosis the discs are kept in compression.
The facet joints in the lumbar spine are aligned front to back and allow flexion and extension of the lumbar spine. If the lumbar spine and the pelvis both function correctly this compression of the disc will be maintained throughout the range of motion and the discs will be safe from damage.
If the movement patterns of the pelvis and lumber spine are incorrect the forces acting on the disc will also be incorrect and the disc will be prone to damage. Most of this happens over a period of months and possibly years and the annular fibres suffer what is effectively a repetitive strain injury as a result of everyday activities that incorporate this incorrect movement pattern.
Slipped discs can be described more specifically
Disc bulge: This is due to radial tears in the annulus allowing disc material to increase the disc volume either centrally or laterally, depending on the area that has accumulated the most radial tears.
Disc herniation: This is also called a subligamentous disc herniation. This occurs when the nuclear material has protruded into the radial tears in one area and has displaced surrounding anatomic structures, i.e., proximal spinal nerve, but has not passed the annulus.
Disc protrusion: A herniated disc is still considered a contained disc as long as the protruding nuclear material is contained by the posterior longitudinal ligament-disc capsule complex.
Radiological reports often use the terms disc protrusion and disc herniation indiscriminately to describe an abnormal bulging of the disc. These terms are often interchangeably used by consultants in their reports and this can lead to confusion. Disc protrusion generally signifies anatomically a focal or diffuse protrusion of the disc with an intact annulus fibrosus. The diffusely bulging disc is broad-based or slightly asymmetric and reflects disc degeneration.
The term protrusion is used to define this radiological appearance of a diffuse disc bulge.
Focal disc protrusion: This is often defined as a disc herniation. The term disc protrusion is inappropriate in this case and the term disc herniation is better as it defines to a focal bulging of the disc due to the extrusion of the nucleus pulposus through a tear on the annulus fibrosis.
Extruded disc or transligamentous disc: This is when the nuclear material is non-contained, since the herniated disc material is extruded beyond the posterior longitudinal ligament-disc capsule complex. Sequestered disc is the end stage of an extruded disc. The once-herniated disc material has lost continuity with its point of attachment to the disc. The disc material can then migrate within the spinal canal, becoming a free fragment.
The important points to be considered when classifying a disc lesion are
• Is the annulus fibrosis is intact.
• Is the posterior longitudinal ligament complex is intact.
• Which anatomic structures are displaced by the disc lesion.
• Do the clinical imaging findings correlate with the clinical symptoms?
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If you have back pain or disc pain and you are in Islington chiropractic care at the Angel Wellbeing Clinic may be helpful. If you want further information or you wish to make an appointment click below.