Written by Lydia Evans
What is a Disc?
What is a disc, and what does it mean when it has slipped? There are 23 discs in the spine, which lie between the bones.
The discs are flat circular shapes made of up to 86% water and contain mainly type one and type two collagen (Reid, J.E et al. 2002). The centre of a disc is made up of a gel-like substance in the middle called the nucleus pulposus; unlike muscles and skin, this substance does not feel any sensation because it doesn't have a nerve or blood supply. This area cannot be felt if a pain stimulus aggravates it.
The disc's outer layer, the annulus fibrosus, comprises a tougher material called collagen. This allows stability of the spine when it moves around, whereas the gel-like centre distributes forces to wherever it needs to go in the disc; it provides flexibility and can swell with water to act as a shock absorber and protective cushion between the bones.
What is a Slipped Disc?
What is meant when a disc slips is that the gel-like centre of the disc can sometimes move beyond its normal distribution due to uneven load through the spine and aggravate the outer layer of the disc (depending on how far out it moves outwards). Unlike the centre, the outer layer of the disc can feel sensations. Sometimes when the centre travels to the outside of its disc, it can irritate nearby nerves. The disc can also travel beyond the outer layers and begin interacting with the surrounding nerves in the spine, causing altered sensations, pain or weakness in the arm(s) or leg(s), depending on where the disc is affected. According to Sonntag (2010), not all people with disc herniation will experience symptoms.
So... What Are My Options?
Over the counter and prescribed medications such as anti-inflammatories and painkillers are used. According to Qaseem A. et al. (2017), there is limited evidence for using muscle relaxants and oral corticosteroids. There are also translaminar injections and selective nerve root blocks, which have little evidence of efficacy beyond three months.
Surgical interventions include discectomies, where there is a partial or complete removal of the disc. There is a procedure whereby the disc is replaced by an artificial one made up of metal and plastic. Spinal fusion is another option, where there is a complete fusion of two or more vertebrae in the spine. This permanently immobilizes that portion of the spine.
According to a study by Dan-Azumi et al. (2018), the outcome after one to two years of having surgery is no different to having conservative care.
Many variables can affect the outcome of recovery. A study by Sabnis and Diwan (2014) suggests that duration of sick leave, low education status, age of more than 40 years, and single or divorced marital status can affect how well people heal from a disc problem. According to a study by Stewart and Loftus (2018), it was suggested that language used to explain what may be happening in a person's body could influence how people think about their health, which can affect healing times and behaviours towards recovery.
According to a study by Lurie, J.D. et al. (2008), Conservative care is the most favourable option. It is reported by Molinaru (2006) that those with sciatica from an acute lumbar disc herniation are expected to improve with conservative care in 90% of people within four months of having the onset of symptoms. It is suggested that people with disc herniations may prefer to avoid surgery due to the risk of surgery complications and the benefit of successful conservative care.
Alves Filho, A.C., Gonçalves, A.L.F. and Barbosa, A.D.M., 2021. Conservative versus surgical treatment in patients with lumbar disc herniation. BrJP, 4, pp.357-361.
Dan-Azumi, M.S., Bello, B., Rufai, S.A. and Abdulrahman, M.A., 2018. Surgery versus conservative management for lumbar disc herniation with radiculopathy: A systematic review and meta-analysis. Journal of Health sciences, 8(1), pp.42-53.
Lurie, J.D., Berven, S.H., Gibson-Chambers, J., Tosteson, T., Tosteson, A., Hu, S.S. and Weinstein, J.N., 2008. Patient preferences and expectations for care: determinants in patients with lumbar intervertebral disc herniation. Spine, 33(24), p.2663.
Molinari, R.W., 2006. Lumbar disk herniation. Current Opinion in Orthopaedics, 17(3), pp.189-194.
Park, D. 2022 Herniated Disc in the Lower Back
Qaseem, A., Wilt, T.J., McLean, R.M., Forciea, M.A. and Clinical Guidelines Committee of the American College of Physicians*, 2017. Noninvasive treatments for acute, subacute, and chronic low back pain: a clinical practice guideline from the American College of Physicians. Annals of internal medicine, 166(7), pp.514-530.
Reid, J.E., Meakin, J.R., Robins, S.P., Skakle, J.M.S. and Hukins, D.W.L., 2002. Sheep lumbar intervertebral discs as models for human discs. Clinical Biomechanics, 17(4), pp.312-314.
Sabnis, A.B. and Diwan, A.D., 2014. The timing of surgery in lumbar disc prolapse: A systematic review. Indian Journal of Orthopaedics, 48(2), pp.127-135.
Sonntag, V.K., 2010. Treatment of the herniated lumbar disc: persistent problem. World neurosurgery, 6(74), pp.574-575.
Stewart, M. and Loftus, S., 2018. Sticks and stones: the impact of language in musculoskeletal rehabilitation. journal of orthopaedic & sports physical therapy, 48(7), pp.519-522.