Back Pain Back Pain Anatomy and Biomechanics 2 — Questions and Answers
Question 1: Which ligament runs along the posterior surface of the vertebral bodies inside the spinal canal?
- Anterior longitudinal ligament
- Posterior longitudinal ligament (Correct answer)
- Interspinous ligament
- Ligamentum flavum
Correct answer: Posterior longitudinal ligament
The posterior longitudinal ligament lines the posterior aspect of vertebral bodies within the canal and partially resists disc herniation.
Question 2: The facet joints of the lumbar spine are oriented primarily in which plane, limiting rotation?
- Coronal
- Transverse
- Sagittal (Correct answer)
- Oblique
Correct answer: Sagittal
Lumbar facet joints are oriented in the sagittal plane, which allows flexion/extension but restricts axial rotation.
Question 3: Which vertebral level marks the termination of the spinal cord in most adults?
- T12
- L1-L2 (Correct answer)
- L3
- L4-L5
Correct answer: L1-L2
The spinal cord typically ends at the L1-L2 level as the conus medullaris; below this level lies the cauda equina.
Question 4: What biomechanical change occurs in the lumbar discs when a person moves from standing to sitting?
- Intradiscal pressure decreases
- Intradiscal pressure increases (Correct answer)
- Disc height increases
- Annular tension decreases
Correct answer: Intradiscal pressure increases
Sitting increases intradiscal pressure compared to standing because spinal flexion shifts load anteriorly and compresses discs more.
Question 5: Which structure is disrupted in a spondylolysis?
- Vertebral body
- Intervertebral disc
- Pars interarticularis (Correct answer)
- Ligamentum flavum
Correct answer: Pars interarticularis
Spondylolysis is a stress fracture or defect in the pars interarticularis, the bony bridge between the superior and inferior articular processes.
Question 6: The erector spinae group includes all of the following EXCEPT:
- Iliocostalis
- Longissimus
- Spinalis
- Multifidus (Correct answer)
Correct answer: Multifidus
The multifidus is a deep segmental stabilizer separate from the erector spinae group, which includes iliocostalis, longissimus, and spinalis.
Back Pain Back Pain Anatomy and Biomechanics 2
Which ligament runs along the posterior surface of the vertebral bodies inside the spinal canal?