Guide to an L4-L5 HNP, or lumbar herniated nucleus pulposus

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

This is typically an age-related condition that occurs with the natural breakdown of the discs over time. However, symptoms of an L4-L5 HNP can be debilitating and interfere with your ability to enjoy a good quality of life. At Laser Spine Institute we are dedicated to patient education as an important part of treatment. If this condition is affecting your life, the following information can help you work more closely with your doctor to find the relief you require. You can also contact our caring and dedicated team to learn more about your treatment options for this condition.

Spinal degeneration and HNP

An L4-L5 HNP affects the spinal disc that supports the two largest vertebrae in the spine — the fourth and fifth lumbar vertebrae. These two vertebrae support much of the upper-body’s weight while still remaining flexible enough to bend and twist. This means a lot of stress is placed on this rubbery and flexible disc that cushions these vertebrae and allows for movement.

After age-related loss of water and protein content combined with years of stress, spinal discs, including the L4-L5, lose elasticity. When a tear develops in the fibrous wall of the disc, the core — called the nucleus pulposus — can push out, or herniate, into the spinal column. This condition isn’t necessarily symptomatic unless the nucleus pulposus irritates the outer layer of the disc or compresses a nearby spinal nerve, resulting in the following symptoms:

  • 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 for an L4-L5 HNP

Treatment options vary depending on the severity and cause of the damaged disc, but in a large number of cases, symptoms are manageable with a series of conservative 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 minimally invasive stabilization surgery that is a safer and effective alternative to 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. We also provide minimally invasive stabilization as an outpatient alternative to traditional fusion procedures for patients with more severely damaged discs.

We are happy to provide you with a no-cost MRI or CT scan review* to determine if you are a potential candidate for one of our procedures.

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