After completing this study unit you will be able to:
- Describe the structure and function of the lumbar spine.
- Identify the features of a typical lumbar vertebra.
- Name the articulations of the lumbar vertebrae and their associated ligaments.
The lumbar spine consists of five lumbar vertebrae, designated L1-L5. They are the largest and sturdiest examples of all vertebrae due to their role in supporting the weight of the upper body. Like their cervical and thoracic counterparts, the lumbar vertebrae articulate with each other via the intervertebral symphyses and zygapophyseal joints. The inferiormost lumbar vertebra, L5, articulates with the sacrum via the lumbosacral joint, which is morphologically similar to the more superior intervertebral joints.
Watch the following video to take a closer look at the lumbar spine and compare its anatomical features with those of the thoracic spine.
Take a quiz
Make all that new knowledge stick with the quiz below!
Have you mastered the lumbar spine and are now looking for an extra challenge? Try out the quiz below and test yourself on the structures of the vertebral column.
Take a closer look at all the distinguishing features of the lumbar vertebrae in the gallery below.
|Structure||Five lumbar vertebrae (L1-L5)|
|Typical vertebra||Vertebral body, vertebral arch, spinous process, transverse process, accessory process, mammillary process, costal process|
Intervertebral symphyses: Between the bodies of the contiguous vertebrae
Lumbosacral joint: Intervertebral and zygapophyseal joints between L5 and sacrum
|Type||Anterior intervertebral joint: symphysis
Facet joints: synovial plane joints
|Articular surfaces||Anterior intervertebral joint: Inferior surface of L5 vertebral body, superior surface of S1 vertebral body
Facet joints: superior articular processes of S1, inferior articular processes of L5
|Ligaments||Iliolumbar ligament, lateral lumbosacral ligament|
|Movements||Flexion, extension, lateral flexion|