Atlas of Human Anatomy by Netter

FACTS & HINTS

High-Yield Facts

Clinical Points
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Types of Vertebral Fractures

Compression fractures

Vertebral body collapses

Caused by osteoporosis, trauma, or tumor

Usually occur at C7 and T1

Moderate to severe pain, limitation of movement, kyphosis

Jefferson fracture

Four part fracture of the ring of C1

Caused by a fall on the vertex

Patients have upper neck pain but can be neurologically intact

Hangman fracture

Caused by hyperextension of the head on the neck

Bipedicle fracture of C2

Anterior displacement of C2 and C3

Results in quadriplegia or death

Cervical Hyperextension

Most common in young adults from trauma and sports injuries and the elderly, resulting in cord compression

Result of whiplash from car accidents

Results in soft tissue injury, fractures, dislocations, ligamentous tears, and disc disruption

Clinical Points

Spinal curvatures: The primary curvatures of the vertebral column in the thoracic and sacral regions develop during the fetal period and are

caused by differences in height between the anterior and posterior aspects of the vertebrae. The secondary curvatures are mainly a result of

anterior-posterior differences in IV disc thickness. The cervical curvature is acquired when the infant begins to lift its head, and the lumbar

curvature when the infant begins to walk.

Abnormal curvatures: Kyphosis is an increased thoracic curvature, commonly seen in the elderly ("Dowager hump"). It is usually caused by

osteoporosis, resulting in anterior vertebral erosion or a compression fracture. An excessive lumbar curvature is termed a lordosis and is

seen in association with weak trunk muscles, pregnancy, and obesity. Scoliosis is an abnormal lateral curvature of the spine, accompanied

by rotation of the vertebrae.

Spondylolisthesis: The lumbosacral angle is created between the long axes of the lumbar vertebrae and the sacrum. It is primarily because

of the anterior thickness of the L5 body. As the line of body weight passes anterior to the SI joints, anterior displacement of L5 over S1 may

occur (spondylolisthesis), applying pressure to the spinal nerves of the cauda equina.

Sacralization: In about 5% of individuals, the L5 vertebra is partially or totally fused with the sacrum. Because the L5/S1 level is now very

strong, the L4/5 level is likely to degenerate in these cases.

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Mnemonics

Memory Aids

Vertebral bodies:

Thoracic are heart-shaped since your heart is in your thorax

Lumbar are kidney-bean shaped as the kidneys are in the lumbar area

Craniovertebral joints:

Atlantooccipital joint is the yes-yes joint because it permits nodding

Atlantoaxial joint is the no-no joint because it permits turning the head from side to side