The document discusses posture, including the development and curvature of the spine, definition of normal and poor posture, types of posture, advantages of good posture, causes of poor posture, and evaluation of posture. It defines normal posture and outlines how to analyze posture from the front, back, and side views by examining spinal curves, pelvic tilt, leg alignment, and other factors. Deviations from normal alignment like kyphosis, lordosis, and scoliosis are also described.

1. KKU_Biomech_M4_L1
Posture
Dr / Shimaa Essa
Lecturer of physical therapy , faculty of community,
King Khalid university
Lesson (1)

2. Upon successful completion of this lesson you would
be able to:
1.
2.
3.
4.
5.
6.
7.
Define normal posture.
Realize the development of posture.
Identify advantages of normal posture.
Distinguish between different types of posture.
Realize types of poor posture.
Analysis posture.
Evaluate deviations of normal posture.

3. The postural alignment starts its development from early
period of life with development of the spine and its
curvature. You we learn what is meant by posture, the
development and characteristics of normal posture,
advantages of correct posture, types of postures, what is
meant by poor or faulty posture, the disadvantages of
poor posture. And practically diagnose posture deviations
of normal.

4. DEVELOPMENT OF POSTURE
The postural alignment starts its development from early
period of life with development of the spine and its
curvature. At first, at birth the spine has one "C"-shaped
curve with one convexity and one concavity. Then, as the
child is trying to raise his head 'from prone lying position
cervical curve starts to develop and in the early phase of
education of walking, another curve will be developed
which is the lumbar curve. These two curves are considered
as "secondary curves" to the first one which is called
"primary curve".

5. CURVATURES OF THE SPINE
1- FROM FRONTAL VIEW:
If the spine is viewed from the
front or the back view it
seems to be straight and
symmetrical.
Posterior (Back) Spinal
Column

6. CURVATURES OF THE SPINE
2- FROM SAGITTAL VIEW:
If the spine is viewed
from the lateral side, four
normal curves will appear
which are:
a- Two primary curves:
dorsal and sacral which
are convex posteriorly.
b- Two secondary curves:
cervical and lumbar which
are convex anteriorly.

7. DEFINITION:
Good posture is the attitude which, is
assumed by Body parts to maintain stability
and balance with minimum effort and least
strain during supportive and non supportive
positions.

8. CHARACTERISTICS OF GOOD POSTURE
(Prerequisites of good posture):
For good posture to be maintained the following
must be obtained:
The ability to maintain 'the body upright in
good and erect position with less energy.
The ability to maintain balance in upright
position via keeping the line of gravity near the
center of the base of support.

9. Effects
of good posture:
Maintaining good posture has its values in different
body functions and systems.
The effects of good posture include:
1- Helps the muscles in the body to be unloaded
and relaxed.
2- Improves respiratory and circulatory
efficiency.
3- Prevents unnecessary strain and fatigue.
4- Decreases the incidence of diseases resulting
from bad posture.
5- Improves the subject’s state; mentally or
psychologically.

10. TYPES OF POSTURE
1) Fatigue posture
2) Easy posture
3) Rigid posture

11. 1- Easy Posture
It Is good, symmetrical and balanced
position
This position can not be maintained for a long
time. So, the subject will shift his weight in a
swaying movement in order to prevent fatigue
and to maintain a good circulation in the postural
muscles of the legs when standing.
By alternating the main support from one leg to
the other; the muscles become periodically
unloaded and relaxed.

12. 2- Fatigue Posture
It is asymmetrical or sagging posture
This position is relaxed and can be
maintained for. a long time as most of
body's joints are in semi-flexion. The load on
the muscles will decrease and the energy
expenditure is 10% less than easy posture.

13. 3- Rigid Posture
It is called posture of attention. It
doesn't mean normal posture
This position can not be assumed
for a long time as most of body's joints
are. In extension; so, the load will
increase on joints and muscles and
energy expenditure is 20% more than
easy posture. So, with referring to 3 types
of posture the energy in:
Rigid > Easy > Fatigue

14. DEFINITION:
Poor posture is a position resulting from any deviation
from ideally aligned erect posture (good posture).

15. CAUSES OF POOR POSTURE:
Poor posture may occur due to:1- Defects in:
•Joints: such as stiffness or immobilization.
•Bones: such as shortening or deformity.
•Muscles: such as weakness, paralysis or contracture.
•Vision or hearing.
2- Bad habits: either from early childhood or from
occupational positions. Example for that is the
workers that perform jobs which require continuous
flexed position of the trunk.
3- Pain, fatigue or bad psychological state.

16. EFFECTS OF POOR POSTURE:
Poor posture causes deviations from the normally aligned
posture. As a result the body functions are altered and this
may lead to dysfunction and diseases. Poor posture may
cause one or more of the following dysfunction:
1. Secondary deformities and compensatory postural
defects.
2. Easy fatigability and high energy expenditure.
3. Decrease both respiratory and circulatory efficiency.
4. Pain, bad cosmetic appearance and psychological
disturbances.

17. Analysis of
Posture

18. To assess posture ideally, the subject stands upright,
and attention should be given to the following:
No movement in the atlantoaxial or atlanto-occipital
joint which results in protrusion of the jaw.
Stands as straight as possible.
Knees should be straight as much as possible.
Head faces forward and arms beside the body.
Almost all joints of the body must be in the neutral
position.

19. Assessment should be From 3 Views:
1- Anterior view.
2- Posterior view.
3- Lateral view.
The Parts Which are Important to be
Observe:
1- Head alignment.
2- Curvature of the spine; cervical, thoracic and lumbar.
3- Shoulders and arms.
4- Pelvic inclination.
5- Hip, knee and ankle joints.

20. Correct Posture (Lateral)
Line is…
• Through external
auditory meatus (Ear)
• Midway through
shoulder
• Through lumbar bodies
• Slightly anterior to
midline of knee
• Slightly anterior to lateral
malleolus

21. Correct Posture (Posterior)
Line is…
• In the center of head,
neck, back and pelvis
• Falls exactly in the mid
point between the two
Knees and ankles
Good Posture

22. Types of Poor Posture
(from the lateral view)
Kyphotic-lordotic Posture
Flat-back Posture
Sway-back Posture

23. Kyphotic-Lordotic Posture
Head- Forward
Cervical Spine- Hyper-lordosis
(hyper-extended)
Thoracic Vertebrate- increased
flexion
Lumbar Vertebrate- Hyperlordosis; (hyperextended).
Pelvis- Anterior tilt (forward and
down)
Knees- hyperextended
Ankle joints- plantar flexed, legs
are behind midline
IDEAL

24. Flat-Back Posture
Head- Forward
Cervical Spine- extended
Thoracic Vertebrate- reduced
curvature (extension)
Lumbar Vertebrate – straight
(flexion)
Pelvis- posterior tilt (backward)
and down)
Hips- extended
Knees- extended
Ankle joints- slightly plantar flexed
IDEAL

25. Sway-Back Posture
Head: Forward
Cervical Spine -Hyper extended
Thoracic Vertebrate- slight flexion
Lumbar Vertebrate –slight
extension
Pelvis-posterior tilt and anterior to
midline
Hips- Hyper extended
Knees- Hyper extended
Ankle- slightly planter-flexed
IDEAL

26. Evaluation
Lateral Evaluation
• Plumb Alignment: aligned anterior to lateral
malleolus
Things to Examine
• Position of knees
– Check for hyperextension or flexion
• Pelvic position and spine curvature
• Head, chest and abdominal position

27. Lateral: Knee Position
Good Alignment
Flexion of Knees
Hyperextension
of knees

28. Evaluation
Anterior Evaluation
• Position of feet
– Check for pronation or supination
– Check arch of the foot
• Position of legs
– Check for bowlegs
• Position of knees
– Check for knock-knees
• Appearance of ribs
• Position of head

29. Anterior: Good Alignment
Knee caps face
straight ahead
Legs are straight
up and down
Toes are straight
Arches have
normal halfdome shape

30. Anterior: Foot Supination & Pronation
Slight knee
knocking
Contracted
anterior
tibalis
Feet are supinated
Weight is
on outside
of feet
Feet are pronated

31. Evaluation
Posterior Evaluation
• Plumb Alignment- align midway between heels
Things to Examine
•
•
•
•
•
Note alignment of Achilles Tendon
Hip adduction/abduction
Check for level posterior iliac spine
Check for lateral pelvic tilt
Check for spine and shoulder problems

32. Posterior Evaluation
Scoliosis
•Lateral curve in the spine
Types of Scoliosis
•Congenital
•Neuromuscular
•Paralytic
•Idiopathic
85% of cases
Unknown Cause
Adolescent Idiopathic Scoliosis (AIS)

33. Posterior Evaluation
Scoliosis: Perform Posture Analysis
Check if shoulders are
level
Check distance between
arms and side of body
Check if hips are level
Check if head is centered
over the pelvis.

34. Posterior Evaluation
Scoliosis
• Shoulders not level,
prominent or uneven
scapulas
• Uneven gap between arm
and body
• Elevated or uneven hip
• Head not centered over
pelvis
• Bending test reveals
uneven portions of back

35. Summary of
Posture

36. o The spinal column has 2 primary curves (Thoracic &
Sacral) and 2 secondary curves (Cervical & Lumber).
o Good posture is the attitude which, is assumed by Body
parts to maintain stability and balance with minimum effort
and least strain during supportive and non supportive
positions.
o Poor posture is a position resulting from any deviation
from ideally aligned erect posture (good posture).
o There are 3 types of normal posture, Easy, fatigue and
rigid postures.
o Evaluation of posture is conducted from 3 views. Lateral,
Anterior and posterior views.