somatic lumbar spine mod 2

How many lumbar vertebrae are typically present?

L1-L5

How do lumbar vertebrae compare in size to the other spinal regions?

They are the largest vertebrae of the spine.

Do lumbar vertebrae have costal facets?

No

What type of curvature does the lumbar spine have?

A lordotic curvature

What basic structures are found on a typical lumbar vertebra?

Vertebral body, pedicles, superior and inferior articular processes, pars interarticularis, laminae, spinous process, and transverse processes.

What shape are the lumbar vertebral bodies?

Kidney shaped

How does anterior vertebral body height compare with posterior height at L1 and L2?

shorter than the posterior height

How does vertebral body height compare anteriorly and posteriorly at L3?

the same

How does anterior vertebral body height compare with posterior height at L4 and L5?

is taller than the posterior height

How are the pedicles oriented at L1 and L2?

They extend directly posteriorly

How are the pedicles oriented from L3-L5?

They extend posteriorly at approximately a 45-degree angle

How are the lumbar pedicles notched?

They are deeply notched inferiorly

What happens to the interpedicular distance from L1 to L5?

It increases

What is the lateral recess?

A space medial to the pedicles bilaterally where descending/transiting nerve roots travel

What happens to nerve roots as they travel through the lateral recess?

They leave the central canal and extend inferiorly and laterally

What can cause narrowing of the lateral recess?

Facet joint arthrosis or a disc protrusion

What can result from lateral recess narrowing?

Nerve root irritation or compression, potentially causing radicular pain or radiculopathy

Are the lumbar laminae imbricated?

No

Which lumbar transverse process is the widest?

L3

Where do lumbar transverse processes project?

They project laterally and posteriorly

What are the main characteristics of lumbar spinous processes?

They are thick, large, club like

At what angle are the lumbar facet joints oriented to the transverse plane?

90 degrees

Which directions do the superior lumbar facets face?

Posterior and medial

What type of surface do the superior lumbar facets have?

A concave surface

Which directions do the inferior lumbar facets face?

Anterior and lateral

What type of surface do the inferior lumbar facets have?

A convex surface

What shape do the facet joints resemble in the upper lumbar spine?

An inverted J

What plane do the upper lumbar facet joints primarily lie in?

The sagittal plane

How does facet orientation change from the upper to lower lumbar spine?

Upper lumbar facets are more sagittal, while lower lumbar facets become more coronally oriented

What is facet asymmetry or facet tropism?

where one facet may be more sagittal and the other more coronal

What are the facet joint angles for the cervical, thoracic, and lumbar spine?

Cervical = 45 degrees, thoracic = 60 degrees, lumbar = 90 degrees

Where does the mammillary process extend from?

posteriorly from the superior articular process.

Why is the mammillary process important clinically?

It can be used as a point of contact when adjusting the lumbar spine.

What attaches to the mammillary process?

Ligaments and muscles, including the multifidus

Where is the accessory process located?

On the posterior aspect of the base of the transverse process.

What is a characteristic of the accessory process?

It is very small and can be difficult to detect

What ligament attaches to the accessory process?

The mamillo-accessory ligament (MAL)

What is the pars interarticularis?

An isthmus or narrow bridge of bone between the superior and inferior articular processes

Where is the pars interarticularis located?

Between the superior articular process (SAP) and inferior articular process (IAP)