Herniated nucleus pulposus (HNP) at L4-L5

A herniated nucleus pulposus (HNP) is another term for a herniated disc. If you have been diagnosed with HNP at the L4-L5 vertebrae, that means you have a herniated disc between the fourth and fifth vertebrae in your lumbar spine.

Also known as a ruptured or prolapsed disc, a herniated disc is a common type of degenerative spine condition typically caused by the regular wear and tear of the spine over time. While this condition often develops slowly as the spine weakens, it can also appear suddenly as a result of an injury or trauma.

Spine degeneration

L4-L5 HNP is a damaged disc that is supposed to support the two largest vertebrae in the spine — the fourth and fifth lumbar vertebrae. These two vertebrae are responsible for the most support of the body’s weight and flexibility, and therefore place the most pressure on the disc in between them that is supposed to be a cushion or “shock absorber” for them.

After years of pressure from constant movement and sometimes weight gain, the disc in the L4-L5 section weakens and loses elasticity. When a tear develops in the fibrous wall of the disc, the nucleus pulposus can extrude into the spinal column. This condition isn’t necessarily symptomatic unless the nucleus pulposus compresses a nearby nerve, resulting in the following symptoms:

  • Sciatica
  • Chronic, lower back pain
  • Soreness or stiffness in the legs, knees or hip joints
  • A burning sensation in the legs
  • Muscle weakness
  • Numbness or tingling

Treatment options

Treatment options vary depending on the severity and cause of the damaged disc, but in most cases disc herniation is manageable with a series of conservative, nonsurgical treatments, including heat therapy, pain medication and exercise.

In the event that your pain persists through several months of treatment, you may be a candidate for the minimally invasive spine surgery at Laser Spine Institute. We offer minimally invasive decompression and stabilization surgery that is safer and more effective than traditional open back surgery^. Many damaged discs can be treated with a decompression surgery; this type of procedure removes the part of the damaged disc that is pressing against the nerve and causing pain. In some cases, the entire disc may need to be replaced with an artificial one to regain stability in the spine; this is done through a stabilization surgery.

To see if you are a candidate for our minimally invasive spine surgery, contact Laser Spine Institute today and ask for a review of your MRI report or CT scan.