curvatures of vertebral column (cervical, thoracic, lumbar, sacral)

Introduction

Vertebral column in adult has 4 curvatures:

• cervical
• thoracic
• lumbar
• sacral

Primary curvatures (thoracic & sacral):

Caused by differences in height between the anterior & posterior parts of the vertebra; retained in the thoracic & sacral regions as the thoracic & sacral kyphosis.

• develop during the fetal period

Thoracic curvature:

• concave anteriorly
• results from the slightly wedge-shaped thoracic vertebral bodies

Sacrococcygeal (pelvic) curvature:

• concave anteriorly
• spans from the lumbosacral joint to the tip of the coccyx

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Secondary curvatures (cervical & lumbar):-

Caused by differences in thickness between the anterior & posterior parts of the IV discs; retained in the cervical & lumbar regions as the cervical & lumbar lordosis.

• develop postnatally in the cervical & lumbar region

Cervical curvature:

• concave posteriorly
• prominent when an infant begins to hold its head erect

Lumbar curvature:

• concave posteriorly
• becomes obvious when an infant begins to walk & assumes the upright posture
• more pronounced in females
• ends at the lumbosacral angle

Function

• the curvatures provide flexible support (shock-absorbing resilience) for the body.

More general terms

• vertebral column