Lumbar and Sacral Vertebrae Flashcards
In relation to the thoracic segment, where is the lumbar segment?
Caudal
How many lumbar vertebrae are there?
Typically 5 but can vary between 4 and 6
What is the main function of lumbar vertebrae?
Weight bearing
How much movement, if any, does the lumbar segment produce?
Little movement due to the interlocking articular facets which are almost perpendicular to the body
What shape are the spinous processes of lumbar vertebrae?
Square
Where and what do the lumbar vertebrae articulate with?
Articulate with each other at inferior and superior articular facets
Articulate with sacrum at the inferior articular facet of L5
What different process is found on the edge of the superior articular facets of lumbar vertebrae?
Mamillary process
What lumbar vertebrae is oval-shaped with the pedicle almost missing?
L5
How many sacral vertebrae are there?
Typically 5 which are fused in adults
What does the sacrum articulate with and where?
Articulates with L5 at the superior articular facet
With coccyx at the facet for coccyx
What are the typical characteristics of the single sacral vertebrae?
Body Lamina Vertebral Canal Spinous process Superior and inferior articular facets
What are the characteristics of a FUSED sacrum?
Alae (wings) which point post superio-laterally
Promontory which articulates with L5
Superuor articular facet which links to L5
Body
Sacral foramina anterior and posterior for sacral nerves (this runs into the sacral canal)
Auricular surface
Median sacrl crest (spine) which runs straight down the middle
Intermediate sarcal crest which is fused with articular facets and ends in line with the posterior sacral foramina
Lateral sacral crest which is fused with transverse processes
Sacral hiatus and sacral cornu
Transverse ridges on anterior side
Sacral canal behind median sacral crest
What is the coccyx?
Evolutionary remnant of a tail
How many coccygeal vertebrae are there?
4-5 fused or unfused
What can the vertebrae of the coccyx form?
Superior cornua
