L5/S1 Herniated Nucleus Pulposus (HNP)


L5/S1 herniated nucleus pulposus (HNP) is a type of spine degeneration situated between the lumbar spine in the lower back and the sacral spine segment in the pelvis. This condition can often cause chronic lower back pain and sciatica, and is particularly common in older patients as a result of the natural aging process.

The role of wear and tear

L5/S1 HNP is often caused by nothing more than regular wear and tear. The lumbar spine in the lower back is the most flexible section of the spine and also supports most of the body’s weight. These characteristics make disc damage common, particularly later in life when the intervertebral discs that cushion the vertebrae have already begun to weaken. However, it is important to understand that the presence of a disc herniation alone usually doesn’t cause pain. An individual experiences chronic pain when the sciatic nerve, spinal cord or another nerve becomes compressed by the herniated disc material.

When the nucleus pulposus – the gel-like center of the intervertebral disc – extrudes into the spinal column through a tear in the fibrous disc wall, the disc material can cause nerve compression. It is this neural impingement that leads to chronic pain and requires treatment.

Symptoms and treatment

L5/SI HNP and nerve compression can lead to a number of pain-related symptoms, including:

  • Local, chronic lower back pain
  • Sciatic pain
  • Muscle weakness or fatigue in the buttocks, legs and feet
  • Numbness or tingling in the feet or toes
  • Soreness or stiffness

In most cases, the aforementioned symptoms can be treated with conservative, non-surgical techniques. However, if your pain persists through several weeks of treatment and you are in the process of considering your other options, contact Laser Spine Institute to learn about our minimally invasive spine procedures for treating L5/S1 HNP.