Within the health profession sector, we come across a lot of common injuries that occur to the spine and discs. These injuries can vary from the top of the spine, neck through to the bottom of the spine finishing in the lower back. Some common misconceptions surrounding discs are their fragility, that they can be easily injured and be easily moveable within our spine. This article intends to broaden the general knowledge surrounding discs and their structural purpose within our spine.
Each disc forms a fibrocartilaginous joint (smooth rubber like elastic tissue padding) between two vertebrae to allow slight movement of said vertebrae and acts as a ligament to hold the vertebrae together. This type of fibrocartilage joint is also known as a symphysis. Within the body, we have other examples of symphysis joints; one is the pubic symphysis which connects to two pubic bones in the anterior pelvis, the second; the joint between the sternum and manubrium in the chest. Both of these joints are EXTREMELY STRONG, very robust and can withstand tremendous amounts of force without failing.
Within the spinal discs, there is an outer fibrous ring called the annulus fibrosus. The annulus creates an exceptionally strong connection to the cartilagenous and endplate layers, making it almost IMPOSSIBLE for the disc to SLIP. The endplates function to hold discs in place and evenly spread applied loads.
Can discs get injured? Yes. Can discs heal? Definitely. How strong are discs, really though? A study examined compressive and tensile strength of thoracic discs in both young and older populations ranging from 20-77 years of age respectively. Results showed it takes around 740Ibs of force to compress the disc height 1mm in young subjects, and 460Ibs of force to compress disc height 1mm in older subjects.
What if a disc is already injured? A further study displayed high percentages of discs that are injured, can subsequently heal.
End story, discs are very strong. They can not slip and can heal!
Hopefully, this has been insightful and allows for greater awareness and knowledge about our discs. However, if there is any concern following an injury whether it be minor or due to greater strain and or force placed through your spine, please do not hesitate to contact a health professional to have it assessed and provide further clarification for you.
Link to study: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2944859/#CIT16