Alignment and orientation of body segments to maintain equilibrium and stability

It encompasses static and dynamic postures, which interact with both internal and external forces

Understanding posture is essential for addressing altered postural control and funcitonal challenges, particularly in clinical settings

Position or attitude of the body, the relative arrangement of body parts for a specific activity or a characteristic manner of bearing one’s body

Relative disposition of the body at any movement, is a composite of the posituon of the different joints of the body at that time

Positions of joints and body segments and also in terms of the balance between the muscles crossing the joints

Area bounded posteriorly by the tips of the heels and anteriorly by a line joining the tips of the toes is considerably smaller than the quadrupedal base

Places stress on the structures responsible for maintaining the body upright in posture

For WB joint to be stable or in equilibrium,

Im the body, the counterforce is either

Upright posture usually involves a slight A-P swaying of the body of about _____, so the muscles are necessary to control the sway and maintain equilibrium

Inert structures that support the body

Dynamic structures that maintain the body in a posture or move it from one posture to another

Defining human trait, offering both advantages and challenges

Where is COM located

Center of mass in children is lower

Relies on passive structures like ligaments, reducing the need for constant muscle activity

Depends on the integration of sensory inputs, CNS and musculoskeletal components

Provides environmental and head position feedback

Detects head movement and spatial orientation via the inner ear

Offers feedback from joints, muscles and skin about body position and movement

CNS processes sensory inputs to generate appropriate postural adjustments

Disruptions impair balance and coordination

Visual system, vestibular system and proprioceptive system

Supplies the structural framework and strength for maintaining stability

Weakness, stiffness or deformities compromise postural control

Forces or movements that disrupt equilibrium, requiring corrective actions

BOS remains unchanged

Ankle and hip strategies

BOS changes

Stepping or grasping responses maintain COM over the BOS

Used for small perturbations

Muscles activate distally to proximally

Used for larger perturbations

Muscles activate proximally to distally

Fewer, larger corrective steps

Multiple smaller, cautious steps

Anterior hip strat response

Posterior hip strat response

Anterior ankle strat response

Posterior ankle strat response

Absent or altered inputs

Altered outputs

Reduced feedback impairs balance

Hinder environmental awareness and head positioning

Causes dizziness and disorientation

Atrophy reduces stabilizing responses

Common in aging and neurological disorders, increasing fall risk

Predictive actions based on expected changes

Compensatory actions in response to unexpected disturbances

Breathing and neurological disorders

Causes minor COM shifts, countered by subtle muscular adjustments

Impair anticipatory and reactive adjustments, increasing fall risk

Maintain head stability during dynamic activities like walking or transitioning from sitting to standing

Crucial for visual focus, orientation and balance

HSS

HST

Head adjusts independently of trunk motion to maintain stability

Anticipates body movements caused by shifts in the center of gravity

Head and trunk move as a single unit

Ensures coordination between head and trunk during movements like sudden directional changes

External forces

Resists changes in motion

More significant in dynamic tasks than static posture

Constant downward force acting on the body

Point of reaction of grf

Rotates joint of LE; opposed by muscles, if not = gait deviations

Generated by muscles, ligaments, and other connective tissues to balance external forces

Stabilize jts and maintain posture

Natural oscillation in static standing

Reflects the body’s ability to adjust and maintain COG over the BOS

Sagittal plane

Frontal plane

Represents the total force appled by the ground on the body

Vertical line representing the direction of gravitational force

In_____ posture, the LoG aligns with GRFV

Supports BW

Stabilizes side to side motion

Stabilizes forward backward motion

Y axis

X axis

Z axis

Reflects the GRFV’s point of application, which shifts with posture and movement

Alignment of body segments to minimize stress on jts, muscles and ligaments while efficiently countering gravitational forces

LOG passes near jt axes, minimizing torque and energy expenditure

Maintained by low level muscle activity and passive tension in ligaments and other connective tissue

Habitual poor posture leads to

Small deviations are normal but large ones increase strain on structures and energy demands

Static posture

Dynamic posture

LOG should pass through or near key landmarks

LOG divides the body into symmetrical halves

LOG and COP shift with movement

Focuses on maintaining balance and recovering from perturbations during movement

Result from LOG deviations from jt axes, creating torques

Generated by muscle activity to counteract external moments and maintain stability

Ideal posture reduces snergy expenditure by minimizing gravitational moments

Faulty postures increase muscular effort leading to fatigue and potential injury

Atlanto-occipital jt

Cervical