Head: Neutral position, not tilted forward or back

Cervical Spine: Normal curve, slightly convex anteriorly

Scapulae: In good alignment, flast against upper back

Thoracic Spine: Normal curve, slightly convex posteriorly

Lumbar Spine: Normal curve, slightly convex anteriorly.

Pelvis: Neutral position, anterior-superior spines in the same vertical plane as the symphysis pubis

Hip Joints: Neutral position neither flexed nor extended.

Knee Joints: Neutral position, neither flexed nor hyperextended

Ankle Joints: Neutral position, leg vertical and at a right angle to the sole of the foot

-Anterior and posterior muscles attached to the pelvis maintain it in ideal alignment.

-Anteriorly, the abdominal muscles pull upward, and the hip flexors pull downward

-Posteriorly the back muscles pull upward, and the hip extensors pull downward

-The anterior abdominal and hip extensor muscles work together to tilt the pelvis posteriorly: the low back and hip flexor muscles work together to tilt the pelvis anteriorly

Head: Forward

Cervical Spine: Hyperextended

Scapulae: Abducted

Thoracic Spine: Increased flexion (kyphosis)

Lumbar Spine: Hyperextended (lordosis)

Pelvis: Anterior tilt

Hip Joints: Flexed

Knee Joints: Slightly hyperextended

Ankle Joints: Slight plantar flexion because of backward inclination of the leg

Kyphotic - lordosis posture muscles

Elongated and weak: 

Neck flexors, upper back erector spinae, external oblique. Hamstrings are slightly elongated but may or may not be weak

Hip flexors are in a shortened position in both the sitting posture and the lordotic posture in standing

Low back muscles may or may not be tight

Back will flatten while sitting

Low back muscle shortness is less prevalent than hip flexor shortness

Short and strong:

Neck extensors and hip flexors

The low back is strong and may or may not develop shortness

Head: Neutral Position

Cervical Spine: Normal Curve (slightly anterior)

Thoracic Spine: Normal Curve (slightly posterior)

Lumbar Spine: Hyperextended (lordosis)

Pelvis: Anterior tilt

Knee Joints: Slightly hyperextended

Ankle Joints: Slight plantar flexed

Elongated and weak:

Anterior abdominals

Hamstring muscles are somewhat elongated but may or may not be weak

Short and strong:

Low back and hip flexor muscles

Head: Forward

Cervical Spine: Slightly extended

Thoracic Spine: Upper part, increased flexion: lower part straight

Lumbar Spine: Flexed (straight)

Pelvis: Posterior tilt

Hip Joints: Extended

Knee Joints: Extended

Ankle Joints: Slight plantar flexion

Elongated and weak:

One-joint hip flexors

Short and strong: 

Hamstrings

Frequently, abdominal muscles are strong

Although back muscles are slightly elongated when the normal anterior curve is eliminated, they are not weak

Sway Back Posture

Head: Forward

Cervical Spine: Slightly extended

Thoracic Spine: Increased flexion (long kyphosis) with posterior displacement of the upper trunk

Lumbar Spine: Flexion (flattening) of the lower lumbar area

Pelvis: Posterior tilt

Hip Joints: Hyperextended with anterior displacement of the pelvis

Knee Joints: hyperextended

Ankle Joints: Neutral. Knee joint hyperextension usually results in plantar flexion of the ankle joint, but that does not occur here becasue of anterior deviation of the pelvis and thighs

Elongated and Weak:

One-hip joint flexors

External oblique

Upper back extensors

Neck flexors

Short and Strong:

Hamstrings

upper fibers of the internal oblique

Strong but not Short:

Low back muscles

The pelvis is in posterior tilt and sways forward in relation to the stationary feet, causing the hip joint to extend.  The effect is equivalent to extending the leg backward with the pelvis stationary.  With posterior pelvic tilt, the lumbar spine flattens.  Hence, there is no lordosis, although the long curve in the thoracolumbar region (caused by the backward deviation of the upper trunk) is sometimes mistakenly referred to as lordosis.