Wk4 muscles tone notes
Stretch of muscle spindles activates afferent fibres
Resistance is modulated by supraspinal activity
Muscle tone: as the resistance to passive stretch due to tension in the muscle
Readiness: of the body’s muscles in preparation for the maintenance of a posture or
movement
Resistance: felt during passive movement of limb throughout ROM. The force the resists a
muscle lengthening is stiffness. Modulated by supraspinal activity
Categories is either High (spasticity) or Low. Pain increases tone
Rigidity – parkinsons
Spasticity – velocity-dependent increase in resistance to passive stretch. lack of inhibition
on the spinal cord increases tone
Factors
Non-neuronal (biomechanical): contractile and non-contractile/ connective tissues
e.g. muscle fibres, collagen, fascia, elastin + other connective tissues ok
- Epimysium and perimysium maintain and hold bundle fibres together muscle. Any
disuse affects the muscle itself and provide an exaggerated feeling of stiffness in
muscle tone. Shortening of muscle
- Non-contractile connective tissues:
Perimysium: connective tissue, maintains alignment and structural support to the
muscle bundles of muscle fibres
Epimysium: surrounds the whole muscle, maintaining muscle shape and support
Disuse contributes to stiffness non-contractile, compromising how muscles move
between each other. Inactivity without neural factor compromises the efficiency of
muscle contraction, result in feeling of stiffness in muscle (Thixotropy - muscle
fluidity)
- Sarcomeres are decreased with disuse and may provide false info on tone
Actin-myosin filaments: rest and inactivity sarcomeres are lost. Shortness, stiffness
Weak, stiff, tight
Scars adhere to muscle decreasing ROM
(viscoelastic properties of non-neural elements provide resistance, particularly at slow
velocities)
Neural control: supraspinal, spinal (Spasms, tremor)
Extrafusal muscle spindles
- Alpha efferent motor neurone
Stretch of muscle spindles activates afferent fibres
Resistance is modulated by supraspinal activity
Muscle tone: as the resistance to passive stretch due to tension in the muscle
Readiness: of the body’s muscles in preparation for the maintenance of a posture or
movement
Resistance: felt during passive movement of limb throughout ROM. The force the resists a
muscle lengthening is stiffness. Modulated by supraspinal activity
Categories is either High (spasticity) or Low. Pain increases tone
Rigidity – parkinsons
Spasticity – velocity-dependent increase in resistance to passive stretch. lack of inhibition
on the spinal cord increases tone
Factors
Non-neuronal (biomechanical): contractile and non-contractile/ connective tissues
e.g. muscle fibres, collagen, fascia, elastin + other connective tissues ok
- Epimysium and perimysium maintain and hold bundle fibres together muscle. Any
disuse affects the muscle itself and provide an exaggerated feeling of stiffness in
muscle tone. Shortening of muscle
- Non-contractile connective tissues:
Perimysium: connective tissue, maintains alignment and structural support to the
muscle bundles of muscle fibres
Epimysium: surrounds the whole muscle, maintaining muscle shape and support
Disuse contributes to stiffness non-contractile, compromising how muscles move
between each other. Inactivity without neural factor compromises the efficiency of
muscle contraction, result in feeling of stiffness in muscle (Thixotropy - muscle
fluidity)
- Sarcomeres are decreased with disuse and may provide false info on tone
Actin-myosin filaments: rest and inactivity sarcomeres are lost. Shortness, stiffness
Weak, stiff, tight
Scars adhere to muscle decreasing ROM
(viscoelastic properties of non-neural elements provide resistance, particularly at slow
velocities)
Neural control: supraspinal, spinal (Spasms, tremor)
Extrafusal muscle spindles
- Alpha efferent motor neurone
