Vertebral Column (Spine)

is a column usually consisting of 24 articulating vertebrae, and 9 fused vertebrae in the sacrum and the coccyx. It is situated in the dorsal aspect of the torso, separated by intervertebral discs. It houses and protects the spinal cord in its spinal canal.

Structures of Vertebrae

Body or centrum: disclike, weight-bearing part of the vertebra facing anteriorly in the vertebral column.

Vertebral arch: arch formed from the joining of all posterior extensions, the laminae extends from pedicles & fuse in the midline, and pedicles w/c extends the body , from the vertebral body.

Vertebral foramen: canal through w/c the spinal cord passes.

Transverse processes: two lateral projections from the vertebral arch.

Spinous process: single projection arising from the posterior aspect of the vertebral arch.

Superior and inferior articular processes: paired projection lateral to the vertebral foramen, allowing a vertebra to from joints w/ adjacent vertebrae.

Regional Characteristics of Vertebrae: (Cervical Vertebrae)

Thoracic vertebrae and lumbar vertebrae:

Different Regions of The Spine:

Central Curvature (concave 7 vertebrae C1-C7)

serves as the framework of the Neck and support the Head. These are flexible bones. The first Cervical Vertebrae is called C1 or the Atlas and the second is called C2 or the Axis.

Parts of Cervical Vertebrae:

*C1- dermatome covers the occiput and top neck

*C2- covers the lower part of neck to clavicle*C3- covers the area just below the clavicle*C4- covers the lateral arm at and above elbow*C5- covers the forearm and thumb side hand*C6- is the middle finger*C7- is the lateral aspects of the hand

Thoracic Curvature (convex

12 vertebrae T1-T12) which is composed of twelve

vertebrae and is located in the chest area or in the middle of the Back. The bone in the Thoracic Vertebrae move with the ribs and protect many vital organs.

It lies in the dorsal portion of the thorax.

Parts of Thoracic Vertebrae:

*T1 covers the medial side of the forearm The thoracic covers the axillary and chest region:*T3-T12 cover the chest and back to hip girdle*T4 covers the nipples*T10 is situated at the umbilicus*T12 ends just above the hip girdle

Lumbar vertebrae (concave 5 vertebrae L1-L5)

Occupying the region of the loin or lumbus.

consisting of five vertebrae. The Lumbar Vertebrae is larger than the Cervical and Thoracic, and carries most of our body's weight.

Parts of Lumbar vertebrae:

L1 covers the hip girdle and groin area

L2 and 3 cover the front part of the thighs

L4 and L5 cover medial and lateral aspects of the lower leg

Sacrum and Coccyx

a fused triangle-shaped vertebra. The Sacrum is originally composed of five vertebrae during childhood and fused into one vertebra after the age of 26. This vertebrae consists the Back wall of the pelvic girdle.

Also known as tailbone, is composed of 3-5 bones that are fused together during adulthood.

Parts of Sacrum: S1 covers the heel and the middle

back of the leg S2 covers the back of the thighs S3 cover the medial side of the

buttocks S4-S5 covers the perineal region S5 is of course the lowest

dermatome and represents the skin immediately at and adjacent to the anus.

Abnormal spinal curvatures:

Lordosis. Also called swayback, the spine of a person with lordosis curves significantly inward at the lower back.

Kyphosis. Kyphosis is characterized by an abnormally rounded upper back (more than 50 degrees of curvature).

Scoliosis. A person with scoliosis has a sideways curve to their spine. The curve is often S-shaped or C-shaped.