Mod 2 Flashcards
Somatic dysfunction in spinal joints may be either…
(1) primary functional disturbance of joint itself
(2) secondary viscerosomatic reflex produced by visceral afferent bombardmen
Activation of ______ fibers produce contraction of _____ fibers in muscle mass
Efferent (motor) alpha nerve
Extrafusal
Activation of efferent gamma nerve fibers produce ___
Contraction of SMALL INTRAFUSAL muscles
fibers of muscle spindle
Proprioceptors transmit info to CNS regarding
LENGTH
TENSION
Three types of muscle proprioceptors are?
Golgi tendon organs (GTO) in tendons
* Primary endings → Annulospiral
* Secondary endings → Flower-spray
What is the role of a GOT
Prevent too much pull from excessive muscle tension
What does a GTO do to prevent too much tension from developing ?
Moniotors change in muscle force
When tension in extrafusal muscle (contraction) pulls on tendon → sends sensory info to spinal cord
To get information into the spinal cord, GTO’s must do what?
Excite inhibitory interneurons that synapse with alpha motor neurons controlling same muscle = causes muscles to relax
What causes involuntary relaxation of extrafusal fibres (think GTO’s)
Rapid lengthening of the GTO
What are muscle spindles?/ Role
Protect muscle from tearing, that are sensitve to change in length
(How much and how fast a muscle is lengthened or shortened.)
Each end of spindle is attached to _____ muscle
fibers
Extrafusal muscle
What are Extrafusal Muscle Fibres ?
The standard skeletal muscle fibers that are innervated by alpha motor neurons and generate tension by contracting, thereby allowing for skeletal movement.
What do Gamma Motor neurons do/ innervate?
Activate the intrafusal muscle fibres, changing the resting firing rate and stretch-sensitivity of the afferents.
Regulate the stretch reflex by adjusting the level of tension in the intrafusal muscle fibers of the muscle spindle.
Spindle & intrafusal fibers innervated by
Gamma Motor neve
What are Annulospiral Primary Receptors
In the Muscle spindle/ Group Ia myelinated afferent, Sense’s length & rate of change
What are Flower-Spray Secondary Receptors ?
In the Muscle spindle Group II smaller, unmyelinated afferent
What is the difference between Annulospiral and Flower-Spray Receptors ?
Annulospiral (Type I)- Sense’s length & rate of change (Velocity & length) Myelinated
Flower-Spray Receptors (type II)- Stretch receptor & length of muscle non-myelinated
I am thinking …“What is the position of the joint and is the joint moving rapidly or slowly?” and what Provides predictive & anticipatory info to CNS.. What am I thinking of?
Proprioceptor–> Muscle Spindle–> Primary Sensory Endings (Annulospiral Endings) Located nucleated portion of intrafusal fibers
The Muscle spindle reports ______ fibers relative
to the __________fibers in the spindle to the CNS
Length of extrafusal muscle
Length of the intrafusal muscle
Rapid lengthening of the muscle spindle Causes…
Involuntary muscular contraction of the intrafusal fibres
What can be “pre-set” by the CNS to allow specific motions without loss of control?
Gamma motor activity to the spindles
So… Muscle injury and loss of control can be prevented
What are instances where inappropriate Gamma motor activity is involved in a mechanism leading to somatic dysfunction?
- Initially set too high in the CNS
- May be a factor in maintaining somatic dysfunction
- Causes a palpable change of the tissues (Ropey feeling)
- Produces restricted motion of the joint, and muscle stiffness
- it can produce cramps in the synergistic muscles
What is Hilton’s Law ?
The principle that the nerve supplying a joint also supplies both the muscles that move the joint and the skin covering the articular insertion of those
muscles
Why is Hilton’s law Important for us?
Palpation provides information of texture and temperature of soft tissue before boney tissue. If there is soft tissue alteration, some degree of hard tissue l esioning b/c superficial & deep tissues are innervated by the same neurology.
