The L5-S1 disc is the most highly loaded lumbar disc, accepting the greatest mechanical stress from the combination of lumbar lordosis and sacral kyphosis. The S1 nerve root is compressed by L5-S1 posterolateral disc herniation, producing pain radiating to the posterior thigh and leg, heel numbness, and plantarflexion weakness. L5-S1 spondylolisthesis (forward slip of L5 on S1) occurs at this level from pars interarticularis defects.
L5-S1 herniation compresses S1, producing absent ankle reflex, plantar foot and posterior leg pain, and gastrocnemius-soleus weakness (single-leg heel rise failure). Isthmic spondylolisthesis from bilateral pars defects allows L5 to slip forward on S1, producing buttock and posterior thigh pain with L5 radiculopathy from the foraminal L5 nerve root compression.
S1 root compression producing absent ankle reflex and posterior leg pain managed with conservative care or microdiscectomy for neurological deficit.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
