Chapter 2

Posture is how the body balances.Muscles, bones, and ligaments all work

together to exert postural control.The nervous system innervates these

structures to regulate growth and function.

Muscles and their nerves…A) provide stability to the trunk.B) produce movement during physiologic

activity.

The motor system consists of bones, muscles, and ligaments.

The nervous system controls the motor system.

Postural analysis is an assessment of the function of the motor system as well as the nervous system.

The brain and nervous system utilize information from three sources to balance the body in space.

Sources of balance…Eyes – level.Ears – vestibular apparatus.Muscles and joints – proprioceptive pathways.

A postural reaction that turns a falling animal's body in space so that its paws or feet are pointed at the ground.

Returns the animal to sternal recumbency after being placed on its back or side.

A normal reaction is dependent on normal vestibular, visual and proprioceptive functions.

Postural changes can be the cause of a clinical problem.

Postural changes can be the effect of a clinical problem.

Orthopedic problems can cause a postural change, which can worsen the orthopedic problem.

Asymptomatic postural problems can produce mechanical stress, which can predispose an individual to injury.

There is no “normal” posture.Ideal posture serves as a reference point.Ideal posture…

Distributes gravitational stress for balanced muscle function.

Allows joints to move in their mid range to minimize stress on ligaments and articular surfaces.

Effective for the individual’s activities of daily living.

Allows the individual to avoid injury.

Good habits contribute to a strong and stable posture.

Bad habits contribute to poor posture and instability.

Excessive sitting.Carrying a heavy backpack.Slumping.Poor sleeping positions.One-sided activities…

Carrying a heavy purse.Sitting on a wallet.Sitting in a twisted position.

Overstressed muscles tighten.Favored muscles weaken.This imbalance perpetuates the poor posture.

Anterior to posterior.Lateral.Helical.Foundational distortions create changes

above.

Palpate for hypertonic (overused) muscles.Palpate for weak / inhibited muscles.A muscle is weak because it is unstressed and

should be strengthened with exercise.An inhibited muscle is not being used

because it’s antagonistic muscle is being overused.

Reciprocal inhibition describes muscles on one side of a joint relaxing to accommodate contraction of muscles on the other side of a joint.

Postural (tend to hyperactivity)

Triceps suraeHamstringsAdductorsRectus femorisTensor fascia latae

(TFL)PsoasErector spinae

Phasic (tend to hypoactivity)

Tibialis anteriorGluteus maximusGluteus mediusRectus abdominusLower / middle

trapeziusLongus capitus and

colliDeltoidsDigastrics

Postural (tend to hyperactivity)

Quadratus lumborum (QL)

PectoralisUpper TrapeziusSternocleidomastoidSuboccipitalMasticatories

Obtain pertinent history.Description of symptoms.Fractures.Injuries.Congenital anomalies.Dominant hand.

Note gross structural asymmetries such as scoliosis.

Occipital protruberance.Cervical, thoracic, and lumbar spinous

processes.Coccyx.Gluteal folds.Arms should hang equally with palms slightly

visible.

The space between the arms and sides of the body should be equal.

Legs should be equally abducted.The backs of the knees should be the same.Ankles and feet aligned b/l (no pronation or

supination).

Structures that should be level and equal.Tips of mastoid processes.Acromia.Scapula.Lower margins of 12th ribs.Iliac crests.Posterior superior iliac spines (PSIS).Ischial tuberosities.

Evaluate from both sides.Landmarks.

External auditory canal.Acromion process of shoulder.Axillary line.Mid-point of iliac crest.Greater trochanter of hip.Lateral condyles of femur.Tibia slightly anterior to lateral malleolus.

Balanced posture should appear equal from left to right.

Landmarks.Bridge of nose.Center of chin.Episternal notch.Xiphoid process.Umbilicus.Pubes.

Arms should hang similarly with palms at the side of the thighs

Shoulder girdle symmetryHands should show similar rotation and

placement on the bodyLegs should appear equally abducted from

the center line

Feet aligned b/lNo pronation / supinationNo inversion of eversion

Knees forward and symmetric b/l

Structures that should be equal b/l and levelEyesClaviclesLower margins of the ribcageAnterior superior iliac spines (ASIS)Femoral trochantersKneesAnkles

Affects the head, neck and shoulders.Result of long-term seated postures.Rolled-in and forward shoulders.Increased thoracic kyphosis.Forward head posture.Loss of cervical lordosis.

Postural findingRounded shouldersForward-drawn headC0-C1

hyperextensionWinging of scapulaeElevation of

shoulders

DysfunctionShortened pectoralsKyphotic t-spineShort suboccipitalsWeak serratus

anterior, weak rhomboids

Shortened upper trap, shortened levator scapulae, weak lower and middle trap

Tight-short musclesSuboccipitalsPectoralsAnterior shoulderUpper trapezius

Weak-long musclesMid to lower

trapeziusSerratus anteriorRhomboids

Affects the lumbar spine and pelvis.Anterior pelvis and increased lumbar

lordosis.Tightness in the psoas and lumbar erector

spinae.Long-term sitting contributes to this

syndrome as well.

Weak gluteus maximus and short hip flexors. Weak abdominals and short lumbar erector

spinae. Weak gluteus medius and short TFL and QL.

Postural findingLumbar hyperlordosisAnterior pelvic tiltProtruding abdomenFoot turned outHypertrophy of

thoracolumbar junction

Groove in iliotibial band

DysfunctionShortened erector

spinaeWeak gluteus maximusWeak abdominalsShortened piriformisHypermobile

lumbosacral junctionShortened tensor

fascia latae

Layered syndrome is a combination of the muscle imbalances seen in both upper and lower crossed syndrome.

It develops with chronic cases.