The lumbar superior articular processes face posteromedially, articulating with the inferior articular processes of the vertebra above to form the zygapophyseal (facet) joints. Their orientation (20-25 degrees from the sagittal plane at L1-L2 to more coronal at L5-S1) determines the proportion of rotational versus sagittal motion permitted at each level.
| Articulations |
|
|---|---|
| Landmarks |
|
| Ossification | Formed from the neural arch ossification centres, fusing to the vertebral body by age 6. |
The orientation of the lumbar superior articular process determines susceptibility to rotational versus flexion-extension injury. More coronally oriented L4-L5 and L5-S1 facets allow more flexion-extension but resist rotation less. Facet joint hypertrophy of the superior articular process is a major contributor to lateral recess and neural foraminal stenosis, compressing the exiting nerve root. Articular process fractures occur in hyperextension injuries and are a component of traumatic spondylolisthesis.
Degeneration of the lumbar facet joints causes low back pain worse on extension and can narrow the lateral recess.
Hypertrophy of the superior articular process compresses the traversing nerve root, causing sciatica.
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.
