Understanding L4-L5 Disc Bulge/ Herniation


Lower back pain remains a prevalent cause of disability worldwide gauging it’s ramifications on work hours affected globally and adverse impact on quality of life. A commonly encountered cause of low back pain encountered in a number of patients across various age groups is disc bulges and disc herniations. The most commonly affected level is the L4-L5 disc owing to a greater degree of movement at this level. Let’s explore what L4-L5 disc bulges are, their causes, symptoms, and available treatment options

What is a L4-L5 Disc Bulge?

The bony vertebrae which compose the spine are punctuated with intervertebral discs which act as shock absorbers and provide flexibility to the spine. A disc bulge, also referred to as disc herniation or slip disc( though technically there is a difference between disc bulge and disc herniation) occurs when the gel-like inner material known as nucleus pulpous of a disc pushes through a weakened or damaged outer layer, namely the annulus fibrosis. This happens due to the dehydration of the disc.In the case of an L4-L5 disc bulge, the offending disc is the one present between the fourth (L4) and fifth(L5) lumbar vertebrae.

Causes : The risk factors leading to the development of an L4-L5 disc bulge include:

  1. Mechanical age related degeneration : As we age, the discs lose their elasticity and become more prone to bulging or herniation.
  2. Repetitive stress : Repeatedly performing activities that strain the lower back, such as heavy lifting or twisting, can lead to disc damage over time.
  3. Poor Ergonomics : Maintaining an incorrect posture while sitting, standing, or lifting heavy objects can place excessive stress on the discs. Repetitive poor posture is a common culprit in people with desk jobs or those who spend a large part of the day in front  of a screen.
  4. Obesity : Excess weight can increase the load on the spine, leading to disc problems.
  5. Trauma : An injury or accident involving the lower back can cause immediate disc bulging or herniation.
  6. Sedentary lifestyle- Lack of physical exercise coupled with an inactive lifestyle can also increase the propensity of developing disc related issues.

Symptoms : The symptoms of an L4-L5 disc bulge can vary from person to person. Common signs and symptoms include:

  1. Lower back pain : Persistent or intermittent pain in the lower back is a typical symptom of disc bulges and is characteristic of discogenic pain.
  2. Radiculopathy or Associated Leg pain : The adjacent nerve roots can get irritated  or compressed by the bulging disc  leading to radiating pain, numbness, or tingling sensations in the buttocks, thighs, or legs. This condition is known as sciatica Focal paresis, restricted trunk flexion, and increases in leg pain with straining, coughing, and sneezing are also indicative of disc bulge.
  3. Muscle weakness : If the compressed nerve affects the muscles in the leg, it can result in weakness or difficulty in lifting or controlling the leg.
  4. Loss of bladder or bowel control : In rare cases where the disc bulge severely compresses the spinal cord, it can cause loss of control over the bladder or bowel function. This condition is called Cauda Equina. This requires immediate medical attention.


Careful history and clinical examination can give a clue towards a history of disc bulge/herniation but MRI is considered as the Gold Standard as it gives details about the level of the disc eg L4-L5, the extent of disc herniation, state of associated nerve roots and the state of the spinal cord(signs of compression).The treatment for a L4-L5 disc bulge depends on the severity of symptoms and their impact on daily life.  common treatment options are

Treatment Options

The treatment for a L4-L5 disc bulge depends on the severity of symptoms and their impact on daily life.  common treatment options are
  1. Rest and activity modification : Taking a break from activities that exacerbate the symptoms and adopting a posture-friendly routine can alleviate discomfort.
  2. Physical therapy : Targeted exercises and stretches can help strengthen the muscles supporting the spine, improve flexibility, and reduce pain.
  3. Pain medication : Nonsteroidal anti-inflammatory drugs (NSAIDs) or muscle relaxants may be prescribed to manage pain and inflammation.
  4. Epidural steroid injections : In some cases image guided corticosteroid injections around the affected nerve can provide  relief from pain and inflammation. Coupled with a good physical therapy regime many people are back to their normal routines.
  5. Comprehensive Platelet Rich Plasma + Prolotherapy is a proliferative injection treatment which helps in strengthening of the ligament bone interface thus increasing the strength of the Lumbar spine.
  6. Surgery : Failure of  conservative treatments calls for  surgical intervention though it is reserved for no more than 10-15% of the cases.. Procedures such as discectomy or spinal fusion may be performed to alleviate pressure on the affected nerve.


While it’s not always possible to prevent an L4-L5 disc bulge, certain lifestyle modifications can reduce the risk. These include
  1. maintaining a healthy weight
  2. practicing good ergonomics
  3. Active lifestyle with exercise


  1. Vroomen P, de Krom M, Wilmink J, Kester A, Knottnerus J. Diagnostic value of history and physical examination in patients suspected of lumbosacral nerve root compression. J Neurol Neurosurg Psychiatry. 2002;72(5):630–634. doi: 10.1136/jnnp.72.5.630. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
  2. Vucetic N, Svennson O. Physical signs in lumbar disc hernia. Clin Orthop Relat Res. 1996. [PubMed]
  3. Kreiner DS, Hwang SW, Easa JE, et al. An evidence-based clinical guideline for the diagnosis and treatment of lumbar disc herniation with radiculopathy. Spine J. 2014;14(1):180–191. doi: 10.1016/j.spinee.2013.08.003. [PubMed] [CrossRef] [Google Scholar]
  4. Kim KY, Kim YT, Lee CS, Kang JS, Kim YJ. Magnetic resonance imaging in the evaluation of the lumbar herniated intervertebral disc. Int Orthop. 1993;17(4):241–244. doi: 10.1007/BF00194188
  5. Akuthota V, Meron AJ, Singh JR, Boimbo S, Laker SR, Brakke Holman R, Sridhar BV, Friedrich J, Sullivan WJ. The utility of magnetic resonance imaging results in physician decision-making before initial lumbar spinal injection. Spine J. 2019 Sep;19(9):1455-1462. [PubMed]
  6. Arici T, Kurçaloğlu M, Eyıgor C, Uyar M. Transforaminal epidural steroid injection and infraneural approach. Agri. 2019 Apr;31(2):104-106. [PubMed]
  7. Taşdemir BB, Aydın ON. [A retrospective investigation of the efficiency of transforaminal anterior epidural steroid injections in patients with low back pain and the effects of interventional pain therapy on quality of life]. Agri. 2019 Apr;31(2):93-100

FAQs – L4-L5 disc bulge

Leave a Comment

Your email address will not be published. Required fields are marked *