Biomechanics of the Nervous System Flashcards
Biomechanics
What are proprioceptors? Name as many as you can.
Nervous System
Sensory nerves located in the muscles, tendons, and joints that are stimulated by motion. Their response depends upon the magnitude, direction, and the rate of change in movement.
- Muscle Spindles
- Golgi Tendon Organs
- Ruffini Endings
- Pacinian Corpuscles
- Mazzoni Endings
- Merkel Discs
Biomechanics
What are muscle spindles?
Nervous System
Muscle spindles are proprioceptors which lie between muscle fibres and give information about changes in muscle length.
Biomechanics
What are golgi tendon organs?
Nervous System
Golgi tendon organs are sensitive to tension (i.e. force) and are located at the muscle-tendinous junction (i.e. between a muscle and a tendon).
Biomechanics
What are paccinian corpuscles and where are they located?
Nervous System
Paccinian corpuscles are located around joint capsules, ligaments and tendon sheaths. They detect joint angle change, intra-articular pressure and vibration.
Biomechanics
What are Ruffini endings and where are they located?
Nervous System
Ruffini endings are located in the deep layers of the skin or within the joints. They detect joint angle changes and intra-articular pressure.
Biomechanics
Which regions of the body have the highest density of proprioceptors?
Nervous System
- Hands
- Cervical Spine
Biomechanics
Describe the stretch reflex of the quadriceps.
Nervous System
- A quick stretch stimulates muscle spindles (receptor).
- The sensory nerve becomes excited.
- The interneuron stimulates the motor neuron of quadricep to contract and stimulated antagonists to relax.
- This results in knee extension.
Biomechanics
Describe the tendon reflex.
Nervous System
- Increasing tension stimulates the golgi tendon organ. (receptor)
- The sensory neuron becomes excited.
- The spinal cord activates inhibitory interneurons.
- The motor neuron receives inhibitory stimulation.
- The muscle relaxes and releases tension.
Biomechanics
Describe the withdrawl reflex.
Nervous System
- A nociceptor becomes activated.
- The excited sensory receptor sends information to the spinal chord.
- Within the spinal chord, several interneurons activate.
- Flexor motor neurones are excited on the affected leg.
- Extensor motor neurons in the opposite leg contract muscles for weight transfer onto that side.
Biomechanics
Describe the Stretch-shortening Cycle and why it improves muscular output.
Nervous System
The Stretch-shortening Cycle refers to the pre-stretch, or countermovement action, that is commonly observed during typical human movement (eg - jumping). It is the load before the explode.
It improves muscular output by:
* Harnessing energy storage in elastic elements of the muscle.
* Potentiating the nervous system by stimulating the stretch reflex and allowing more time for muscular recruitment.
Biomechanics
Broadly, name two things that improve neural health and two things that irritate the nervous system.
Nervous System
- Nerves like space and mobiltiy.
- They do poorly under tension or compression.
Biomechanics
What does a nerve being velocity dependant mean?
Nervous System
Nerves do not stretch well. The gliding and deformation of a nerve under tension takes time to adapt. Thus, nerves can perform functional motions slowly that they otherwise couldn’t do quickly.
