Question

What is the epidemiology of herniated nucleus pulposus (HNP)?

1) Age
2) 80
3) 35
4) Most common in what 3 areas and which one of those is most common

Answer 1

Herniated nucleus pulposus is more common with increasing age, particularly after the age of 35, and most commonly affects the L5/S1, L4/L5, C5/C6, and C6/C7 intervertebral discs, with L5/S1 being the most frequently affected area.

Step-by-step explanation:

The epidemiology of herniated nucleus pulposus (HNP) indicates that it is more common with increasing age, particularly in individuals around and after age 35. As individuals get older, the water content of the nucleus pulposus decreases, resulting in reduced flexibility and increased susceptibility to herniation. Heavy lifting or strenuous activity can exacerbate this issue, particularly if the posterior anulus fibrosus is already weakened. The most common areas for HNP are within the lumbar and cervical regions of the spine, specifically the L4/L5, L5/S1, C5/C6, and C6/C7 intervertebral discs, with L5/S1 being the most frequently affected area.

Herniations at these sites can lead to symptoms such as sciatica, where pain radiates from the lower back into the leg, or neck and upper limb pain, depending on the location of the herniation. The most common sites for disc herniation are the L4/L5 or L5/S1 intervertebral discs, which can cause sciatica, a widespread pain that radiates from the lower back down the thigh and into the leg. Other factors, such as injury and lifting heavy objects, can also contribute to the development of HNP.