[Doctor-supervised] What is lumbar disc herniation? Explanation of causes, symptoms, and treatment options from conservative therapy to stem cell therapy.

Are you worried that severe pain in your lower back or buttocks might be a herniated disc? Lower back and buttock pain is not uncommon among working-age adults. This article provides a clear explanation of herniated discs, including accurate information and treatment options ranging from conservative therapy to regenerative medicine.

What is a herniated disc? Mechanism and patient background

A herniated disc occurs when a portion of the intervertebral disc, which acts as a cushion between the vertebrae, protrudes and compresses the nerves, causing pain and numbness. It can develop suddenly due to trauma such as an accident, or it can be triggered by poor posture during activities.

What is a herniated disc?

The intervertebral discs, made up of a fibrous ring and a nucleus pulposus, connect the vertebrae of the spine and act as cushions. A herniated disc is a condition in which a portion of the intervertebral disc protrudes and compresses the nerves, causing symptoms such as pain and numbness. It can suddenly develop due to trauma such as an accident or repeated minor injuries, or it can be more likely to occur when lifting heavy objects in an awkward posture.

Patient characteristics of intervertebral disc herniation

The male-to-female ratio is approximately 2-3:1, with herniated discs being more common in men. The most common age of onset is between 20 and 40 years old. The reason it is common in this age group is thought to be that [mf1.1], when strong pressure is applied during a period when the membrane covering the intervertebral disc is weakened, the contents are more easily pushed out through the fragile parts or tears in the membrane. More than 80% of cases occur in the lower lumbar spine (between the vertebrae L4/L5 and L5/S1), but after the age of 50 [mf2.1], the contents of the intervertebral disc harden, so it is said that herniated discs become less likely to occur.

Factors contributing to the development of intervertebral disc herniation [mf3.1]

While various factors may contribute to the onset of the condition, it is unclear whether environmental factors or sports are contributing factors.

environmental factors

While some reports indicate a higher incidence among heavy laborers, professional drivers, and metal and machinery workers, studies comparing these groups to control groups have shown contradictory results, and no clear conclusion has been reached. Furthermore, studies comparing sports such as baseball, golf, tennis, soccer, wrestling, and swimming to control groups have found no clear association.

Genetic factors

On the other hand, it is known that juvenile intervertebral disc herniation is highly familial, with the same tendency being observed from parent to child or among siblings.

Reference: Japanese Orthopaedic Association | Orthopedic Series 2 "Lumbar Disc Herniation"
References: Japanese Society for Clinical Orthopaedic Surgery | Lumbar Disc Herniation ; Japanese Orthopaedic Association | Lumbar Disc Herniation Treatment Guidelines

A herniated disc is a dangerous symptom that should not be overlooked.

The typical symptoms of a herniated disc are as follows:

• Lower back and buttock pain
• Numbness and pain radiating to the lower limbs
• I have difficulty putting weight on my legs.
• It becomes difficult to move.

The pain may worsen when lifting heavy objects or moving, and the spine may curve sideways to avoid pain (painful scoliosis). Particular attention is needed if there is significant nerve damage. Severe compression of the nerve roots can cause paralysis of the legs. Furthermore, if the cauda equina, a bundle of nerves located beneath the spinal cord, is affected, there is a risk of losing control of the bladder and intestines, leading to incontinence. If you experience such urinary problems, you should seek medical attention immediately.

Reference: Japanese Society for Clinical Orthopedic Surgery | Lumbar Disc Herniation

Conservative treatment of herniated discs

Unless the nerve loss is progressive or severe, the basic treatment is conservative therapy. During periods of severe pain, rest is necessary, and pain is controlled with oral anti-inflammatory and analgesic drugs, vitamins, and muscle relaxants, as well as epidural blocks, nerve root blocks, and the use of a corset. When the pain subsides, exercise therapy such as traction therapy and abdominal muscle training is performed. Strenuous exercise is restricted, but walking and light activities are permitted within acceptable limits.

Reference: Keio University Hospital | Understanding the Disease "Lumbar Disc Herniation"
References: MSD Manual | Lumbar Disc Herniation ; Japanese Orthopaedic Association | Orthopedic Series 2 "Lumbar Disc Herniation"

When surgery is necessary, and when regenerative medicine is an option.

Even if diagnosed with a herniated disc, immediate surgery is only necessary in a limited number of cases. If there are no severe symptoms, alternative treatments can be considered. In recent years, regenerative medicine, which promotes tissue repair without surgery, has also been attracting attention as a new treatment option.

If surgical intervention is necessary

A herniated disc does not automatically mean immediate surgery. Immediate surgery is necessary only in cases of urinary or bowel dysfunction (cauda equina syndrome) or when paralysis (muscle weakness) of the lower limbs is rapidly progressing. Surgery may also be considered if pain does not improve after more than three months of conservative treatment and significantly impairs daily life. In other cases, there is room to consider non-surgical options. It is important to note that even if the protruding portion is surgically removed, the degeneration (aging) of the intervertebral disc itself is not cured, so there is a possibility of recurrence in the same or different location.

Application of regenerative medicine to herniated discs [mf4.1]

In recent years, regenerative medicine has been researched as a new treatment option. One treatment method involves concentrating platelets taken from the patient's own blood and administering them to the affected intervertebral disc. In addition, in stem cell therapy, the relationship between cytokines (repair substances) released by stem cells and nerve inflammation is being studied.

However, these treatments are not yet established as standard medical care, and many aspects of their indications and effectiveness are still under research. This is an area where further research is eagerly awaited.

Reference: Intradiscal administration of autologous platelet‐rich plasma in patients with Modic type 1 associated low back pain: A prospective pilot study

summary

While the mechanisms behind the development of herniated discs are not entirely clear, a diagnosis does not necessarily require immediate surgery. In most cases, conservative treatment is attempted, and surgery is considered only if the condition does not improve. The age group most susceptible to herniated discs coincides with busy generations who hold responsible positions at work and at home. Many people continue to work despite the pain, or are too busy to attend treatment. For those who wish to avoid surgery and hospitalization, regenerative medicine holds new potential for improving symptoms.