Seattle Dizzy Group

Postural Control & Balance

by Morgan Kriz, DPT

Vestibular Physical Therapist

 (Presented to Seattle Dizzy Group on 4/14/18)

This presentation gives an overview of how postural control helps maintain balance including the role of the cervical spine and the somatosensory system (musculoskeletal and joint systems).  It also offers a few strengthening and stretching exercises to practice for maintaining better posture and improving balance.

Balance is the ability to maintain the body’s center of mass over its base of support

Balance/stability is achieved and maintained by a complex set of sensorimotor control systems that include sensory input from 3 main systems:

1. Vestibular System/Inner Ear (motion, equilibrium, spatial orientation)
2. Vision (eyes)
3. Somatosensory/Proprioception (sense of body’s position)

These systems are connected to each other and to the brain to help maintain good balance.

Vestibular System

• Size of a coin

• 5 end organs
  • 3 semicircular canals
    • Angular accelerations of the head
  • 2 otolith organs
    • Linear accelerations
    • Utricle
    • Saccule

Semicircular canals — Full of fluid that moves when you move your head around (little “fish bowls”)

Otolith Organs — Where otoliths live on a bed of jello

Vision System

Vision is human’s strongest sense

80% of what we learn is through our eyes

40% of our brain is mapped to connect to vision

• Make sure you have vision exam annually
  • Ensure proper prescription for glasses

• Bifocal and progressive lenses considerations

• Eyes and inner ears communicate
  • Via Vestibulo-Ocular Reflex (VOR)
  • Practice gaze stabilization

• Eyes and the body connect
  • Via Cervico-Ocular Reflex (COR)

Vestibular Dysfunction

People with vestibular disorders often experience problems with vertigo, dizziness, visual disturbances and/or balance.

Other problems also arise that are secondary to vestibular disorders, such as nausea and/or vomiting, headaches, “foggy headedness,” heavy headedness, reduction in one’s ability to focus or concentrate and increase fatigue.  (Cervical spine issues can also cause or exacerbate foggy or heavy headedness).

These impairments can be life-altering.

The Brain Controls It All

The midbrain is like a busy mail room.  Incoming messages need to be sorted and sent on.  Error signals cause system alarms (resulting in symptoms such as nausea, headache, etc.).

Brainstem = Body’s Highway

• The brainstem controls the flow of messages between the brain and the rest of the body.  Sensory and motor neurons connect through here to the brain.

• It also controls basic body functions such as:
  • Breathing
  • Swallowing
  • Heart Rate
  • Digestion
  • Blood Pressure
  • Consciousness (whether one is awake or sleepy)
  • Vestibular System
  • Motor Movement (particularly movements of the eye)
  • Auditory and Visual Processing

Definitions

Posture:  The position in which someone holds their body when standing or sitting.  Other:  An approach or attitude.  (Attitude plays a role in brain function.  It is important to give the brain positive encouragement.  For example, congratulate the brain for milestones achieved in the healing process).  Posture and attitude are interconnected.  (For example, good posture brings confidence).

Somatosensory:  Relating to or denoting a sensation (such as pressure, pain, or warmth) that can occur anywhere in the body, in contrast to one localized sense organ (such as sight, balance, or taste).

Proprioception:  The unconscious perception of movement and spatial orientation arising from stimuli within the body itself.  (Humans use nerves, joints, and semicircular canals of the inner ear).

Human Body Anatomy

• Muscles = 640
  • Eye muscles = 6
• Joints = 360
• Circulation System = 60,000 miles
• Nerves = 95-100 billion
  • Nerves in Brain = 85 billion (of the 100 billion total nerves in the body)

Nerves are like “cords” of the body’s “entertainment system.”  After an injury or onset of an inner ear or balance disorder, Vestibular Rehabilitation Therapy (VRT) helps to organize the “cords” so that the brain and body can relearn to function properly together.

Body Reflexes for Posture

Maintaining balance is complex.  It is dependent on maturity of the nervous system, mobility of the joints in the spine and limbs and muscle power. 

• Involuntary:  Goosebumps when cold, eyes water when cutting an onion
• Voluntary:  Walking, slapping someone when someone slaps you

Occur through habit.

We get these in the developmental stages of life (start after being born = gravity must be involved).

Vestibulospinal Reflex (VSR):  Motor output to skeletal muscle below the neck

Neck Reflexes

The neck is the bridge between the brain and the body.

• Vestibulocollic Reflex (VCR)
  • Reflex for the neck musculature in order to stabilize the head
  • Neck movement counters the movement sensed by the otoliths or semicircular canals

• Cervicospinal Reflex (SSR), also known as Tonic Neck Reflex (TNR)
  • When neck moves, body stabilizes/changes position

• Cervicocollic Reflex
  • Stabilizes head on the body (like toothpick with a bowling ball on it)

• Cervico-ocular Reflex (COR)
  • Eye movements driven by neck proprioceptors

Cervical Spine Anatomy

Atlanto-occipital (AO):  flexion/extension “yes joint”

Atlanto-axial (C1-2):  rotational/lateral “no joint”

Lower cervical spine (C3-C7):  rotation

Position of the Spine Matters!

Muscle tightness can change the position of bones and spine.  This can impact blood flow and bring on symptoms such as headache/migraine.  Try not to associate muscle tightness with pain, but instead use muscle tightness as a signal to change/improve posture.  Practice exercises regularly to relieve muscle tightness, change bad habits and improve posture, and increase efficiency of muscles (move easier).

Exercise Tips

• It is important to be proactive to exercise to calm your brain prior to it becoming overwhelmed and triggering symptoms.

• While exercising, use diaphragmatic (deep) breathing to oxygenate the body.

• Try using phone apps for postural check reminders and breathing pace/biofeedback exercises (for example, the Calm app).

• A foam roller or lacrosse/tennis ball or trigger point roller ball (pictured below) may be used to help relieve muscle tightness.

Base of Support

Try Exercises With Your Eyes Closed

• If we are 80% visually dominant, consider connecting your brain better with other systems (for example, the somatosensory system)

• Continue exercises/movement but try to also do so with your eyes closed (be safe!)

• You may have to make balance stance easier to be successful (try not to grab for walls, instead make balance control internal)

• Purpose:  To know your boundaries in space and catch yourself (increases confidence and reduces fear of falling)

Considerations

• Sitting
  • Move every 15 minutes
  • Neck range of motion
  • Stand up every hour
  • Knees hip width apart
  • Ankle rolls/toe tapping
  • Shoulders down and back
  • Screen/book directly in front
  • Breath from belly

• Standing/Walking
  • Stand tall
  • Keep big toes down
  • Shoulders down and back
  • Engage core
  • Look at stable object in the distance
  • Swing arms
  • KEEP MOVING!

Recommended Books

Migraine Brains and Bodies by C.M. Shifflett

The Brain Always Wins by John Sullivan

 

Morgan Kriz, DPT

Vestibular Physical Therapist