Transcript Balance
Common Sense Rules For Balance Spatial Orientation Horizontal Reference Vertical Reference All Tasks Require Postural Control Postural Mechanisms Postural Control System Nystagmus Postural Control and Balance Cone of Stability Movement Sequence Balance Strategies Attention Demands Posture Map of Essential Concepts Balance Tests Balance Exercises Fall 2006 DM McKeough Posture Control and Balance Common sense rules of balance Spatial orientation Posture Postural control system Horizontal reference Vertical reference ALL tasks require postural control Nystagmus Postural Mechanisms Movement sequence Cone of stability Balance strategies Attentional demands Balance tests Balance training exercises Last Viewed Posture & Balance Concept Map Exit Common Sense Rules of Balance Rule Get up Stay up Don’t fall down If you do fall down don’t hit your head Last Viewed Posture & Balance Movement Solutions Place center of gravity over the base of support Maintain center of gravity over base of support Have adequate equilibrium responses Have protective responses Concept Map Exit Spatial Orientation 1/2 Balance = Stability + Spatial Orientation Spatial Orientation Cartesian coordinate system divides space into X, Y, Z planes We orient our body in space according to its relationship to the 3 planes Last Viewed Posture & Balance Concept Map Exit Spatial Orientation Last Viewed Posture & Balance 2/2 Concept Map Exit Posture Postural requirements change for different tasks and different environments Reading a paper while sitting, standing, or riding a bus Each individual solves postural demands with their unique movement ability Last Viewed Posture & Balance Individual Task Posture Environment Concept Map Exit Postural Control System 1. Sensory Input Vision Vestibular Somatosensation (Proprioception) 2. Central Integration Spatial orientation 3. Motor Output Extensor muscles Postural control system is complex interaction of musculoskeletal and neural systems Last Viewed Posture & Balance Concept Map Exit Sensory Systems in Balance Visual System Provides a reference for horizontal in environment Head righting reactions Midbrain level reflexes designed to maintain the eyes in the horizontal plane Last Viewed Posture & Balance Concept Map Exit Sensory Systems in Balance Vestibular System Gravity and motion receptors that provide a reference for vertical in environment Helps determine position of head in reference to vertical Last Viewed Posture & Balance Concept Map Exit Sensory Systems in Balance Somatosensation (Proprioception) Mechanoreceptors provide body awareness Neck proprioceptors connect head position with body position to provide spatial orientation (body Visceral Nervous System Intero-ceptors provide position in space) information about the environment inside the body Last Viewed Posture & Balance Somatic Nervous System Extreo-ceptors provide information about the environment outside the body Concept Map Exit Postural Control System 2. Central Integration Spatial orientation “Perception” of a body’s “posture” and its relative position in Cartesian space Produced by central integration of visual, vestibular, and somatosensory information Vast majority of posture and balance is regulated reflexively at subcortical levels Last Viewed Posture & Balance Concept Map Exit Postural Control System 3. Motor Output Produce sufficient force to oppose gravity (Extensor muscles) and maintain LOG inside BOS Vestibular system has direct input to antigravity muscles to maintain erect posture (vestibulospinal tract facilitates axial extensor muscles) Last Viewed Posture & Balance Concept Map Exit ALL Tasks Require Postural Control Orientation component Stability component Visual Vestibular Somatosensory Sufficient force production to maintain COG inside BOS Example: reading a book while: Sitting, standing, or riding a bus Last Viewed Posture & Balance Concept Map Exit Nystagmus Nystagmus is rapid involuntary rhythmic eye movement, with the eyes moving quickly in one direction (quick phase), and then slowly in the other (slow phase). The direction of nystagmus is defined by the direction of its quick phase (e.g. right nystagmus is due to a right moving quick phase). Dix-Hallpike Test Last Viewed Posture & Balance Concept Map Exit Postural Mechanisms What mechanism does the Ventromedial Motor System use to auto-regulate balance during quiet posture? Muscle spindles and the stretch reflex in antagonistic pairs of muscles What must be done before the Dorsolateral Motor System can produce smooth, coordinated manipulation on top of the postural set? Reciprocal inhibition of antagonists Last Viewed Posture & Balance Concept Map Exit Movement Sequence During the performance of every task what component of the movement occurs first? Postural set (anticipatory postural adjustment) What happens next? Manipulation is superimposed on a stable base Last Viewed Posture & Balance Concept Map Exit Cone of Stability Distance the COG can travel before leaving the BOS Anterior > Posterior Last Viewed Posture & Balance Concept Map Exit Balance Strategies Anterior-Posterior Strategies Medial-Lateral Strategies Last Viewed Posture & Balance Concept Map Exit A-P Balance Strategies 1/2 Ankle strategy Hip strategy Stepping strategy Stepping Strategy Hip Strategy Ankle Strategy C of G Flat Surface Last Viewed Narrow Beam Posture & Balance Concept Map Exit A-P Balance Strategies Different strategies used depending on mass and displacement 2/2 Ankle, hip, stepping strategies Muscle patterns organized in a distal-toproximal direction Ankle strategy: distal Hip strategy: intermediate Stepping strategy: proximal Last Viewed Posture & Balance Concept Map Exit Ankle Strategy 1/2 Postural sway control from the ankles and feet Head and hips move in the same direction, at the same time, as a unit Response to small, slow, midline displacement Surface broad and stable enough to allow pressure against it Last Viewed A-P Strategies Concept Map Exit Ankle Strategy Last Viewed A-P Strategies 2/2 Concept Map Exit Hip Strategy 1/2 Postural sway control from the hip, pelvis, trunk Head and hips travel in opposite directions (Counteract) Used when movement is large, fast, nearing the limit of stability Surface is too narrow or unstable to allow counter pressure Last Viewed A-P Strategies Concept Map Exit Hip Strategy Last Viewed A-P Strategies 2/2 Concept Map Exit Stepping (Reaching) Strategy An attempt to reestablish a new base of support with the active limb when the COG has exceeded the original base of support Last Viewed A-P Strategies Concept Map Exit M-L Balance Strategies Alternative strategies used to recover stability in mediolateral direction Muscle patterns organized in a proximalto-distal direction Last Viewed Balance Strategies Concept Map Exit Cognitive Systems in Postural Control Nervous system must distribute limited attention capacity between postural, manipulative, and cognitive systems Dual task paradigm Attentional demands of postural control are small unless the system is stressed When you slip on the ice you stop searching for your keys Last Viewed Posture & Balance Concept Map Exit Clinical Examination of Balance Functional Reach Clinical Test of Sensory Integration and Balance Last Viewed Posture & Balance Concept Map Exit Functional Reach Test Finish 1/2 Start 25.5 -8.5 17.0 (Duncan 1990) Last Viewed Balance Tests Concept Map Exit Functional Reach Interpretation 2/2 Normal 15 inches < 10 inches: increased risk of fall 5 inches: x 5 increased risk of fall For every inch less than 10 x 1 increased risk of fall Intervention Although this test can identify an activity limitation (functional limitation) it does not identify the responsible body structure or function (impairment) and tell us what to treat (Duncan 1990) Last Viewed Balance Tests Concept Map Exit Clinical Test for Sensory Integration and Balance (CTSIB) (Foam and Dome Test) 1/8 EYES OPEN Functional test of the effects of various sensory systems on balance Record the time performer is able to maintain hand contact on shoulder under various testing conditions Maximum of 30 sec per condition Last Viewed Balance Tests EYES CLOSED DOME FIRM SURFACE COMPLIANT SURFACE Concept Map Exit Condition 1 2/8 EYES OPEN All three senses are available and accurate Vision Vestibular Somatosensory FIRM SURFACE Last Viewed Balance Tests Concept Map Exit Condition 2 3/8 EYES CLOSED Vision: unavailable Accurate senses Vestibular Somatosensory FIRM SURFACE Last Viewed Balance Tests Concept Map Exit Condition 3 4/8 DOME Vision is inaccurate Accurate senses Vestibular Somatosensory FIRM SURFACE Last Viewed Balance Tests Concept Map Exit Condition 4 5/8 Support surface can sway (Somatosensory cues are available but inaccurate) Accurate senses EYES OPEN Visual vestibular COMPLIANT SURFACE Last Viewed Balance Tests Concept Map Exit Condition 5 6/8 Vision: unavailable Somatosensory cues are available but inaccurate Accurate senses EYES CLOSED Vestibular COMPLIANT SURFACE Last Viewed Balance Tests Concept Map Exit Condition 6 7/8 Vision: inaccurate Somatosensory cues are available but inaccurate Accurate sense DOME Vestibular COMPLIANT SURFACE Last Viewed Balance Tests Concept Map Exit Sway By Condition Last Viewed Balance Tests 8/8 Concept Map Exit Balance Training Exercises 1/4 “Kitchen sink exercises” (Shumway-Cook) Stand supported at kitchen sink (look out the window – stand up straight) 1. Toes up, heels up 2. Side ticks, back kicks 3. 1/4 squats 4. Knee to counter Last Viewed Posture & Balance Concept Map Exit Balance Training Exercises 2/4 “Kitchen sink exercises” (Shumway-Cook) Stand supported at kitchen sink (look out the window) 1. Toes up, heels up 2. Side ticks, back kicks 3. 1/4 squats 4. Knee to counter Last Viewed Posture & Balance Concept Map Exit Balance Training Exercises 3/4 “Kitchen sink exercises” (Shumway-Cook) Stand supported at kitchen sink (look out the window) 1. Toes up, heels up 2. Side ticks, back kicks 3. 1/4 squats 4. Knee to counter Last Viewed Posture & Balance Concept Map Exit Balance Training Exercises 4/4 “Kitchen sink exercises” (Shumway-Cook) Stand supported at kitchen sink (look out the window) 1. Toes up, heels up 2. Side ticks, back kicks 3. 1/4 squats 4. Knee to counter Last Viewed Posture & Balance Concept Map Exit Age-Related Changes in Balance Components Sensory Vision Vestibular Proprioception Central Integration Spatial orientation Motor Extensor muscles Last Viewed Posture & Balance Age Related Changes Exercise Effects Concept Map Exit The End © DM McKeough 2006 Last Viewed Posture & Balance Concept Map Exit