S3_L5: Postural Control Flashcards
An unsupported posture in which a person attempts to sit up as straight as possible
Active erect sitting posture
A sudden cessation of muscular activity, as manifested by electrical silence of the back extensors during trunk flexion in either sitting of standing postures
Flexion relaxation phenomenon
Pressure caused by contact forces between the person’s body and the seat
Seat interface pressure
A compensatory posture where the head is positioned anteriorly and the normal anterior cervical convexity is increased with the apex of the lordotic cervical curve
Forward Head Posture
Source: Levangie & Norkin, 5th
A compensatory posture where hyperextension at the knee is usually caused either by limited dorsiflexion at the ankle or by a fixed plantarflexion position of the foot and ankle called equinus.
Genu recurvatum
Source: Levangie & Norkin, 5th
Postures that represent an attempt to either improve function or normalize appearance
compensatory postures
Source: Levangie & Norkin, 5th
TRUE OR FALSE: With more stability due to more muscle bulk, males are relatively more stable than females.
True
During pregnancy, the CoG shifts ___, challenging the stability. This results in an increase in the lordotic curves in the cervical and lumbar areas of the vertebral column, protraction of the shoulder girdle, and hyperextension of the knees.
Forward / anteriorly
TRUE OR FALSE: A taller individual has a higher CoG, which makes them more unstable
True
TRUE OR FALSE: A heavier individual is more stable and more difficult to perturb.
True
The sum of all of the external and internal forces and torques acting on the body and its segments must be equal to ____ for the body to be in equilibrium.
Zero
Any sudden change in conditions that displaces the body away from equilibrium. An eternal force applied, just one type of activity that is related to postural control.
Perturbation
TRUE OR FALSE: Proprioception is not just related to sensory perturbation, as it can also be activated in mechanical perturbation.
True
For balance control, there is an interaction between 3 systems. Enumerate all.
- Visual system
- Somatosensory system
- Proprioceptive / Vestibular system
Determine the corresponding descriptions of the perturbation types
- E.g. standing on soft or wobbly surface, push, nudge
- Alteration of visual input, environment cannot be seen
- Also addresses proprioception
- External force that challenges CoG to be maintained within the BoS
A. Sensory perturbation
B. Mechanical / Contact perturbation
- B
- A
- A
- B
When unable to see, an automatic mechanism that makes an individual slouch and ___ their arms. This is a safety mechanism in the absence of visual input.
Extend
Posture where the body and its segments are aligned and maintained in certain positions. E.g. sitting, standing, lying, kneeling.
Static posture
Posture where the body and its segments are moving. E.g. walking, running, jumping, throwing, and lifting.
Dynamic posture
An abnormal increase in the normal thoracic posterior convexity
Kyphosis
A stance where the body weight is distributed in UE & LE. It is composed of 1 whole kyphotic curve and this stance is to maintain a stable position.
Quadrupedal stance
A stance that is unique to humans. It increases the work of heart and stress on vertebral column, pelvis, and LE. The BoS is reduced with this stance and secondary curves and adjustments are a result.
(Erect) Bipedal Stance
Postural control where the individual reacts to an external force displacing the body’s CoM. A force came into contact with body thus changing the CoM outside of its equilibrium state.
Reactive / Compensatory
The nudge test is used for this postural control.
Reactive / Compensatory