CSkills 2 - Tone Abnormalities and Motion Restrictions

What is muscle tone

Underlying tension in the muscle that serves as a background for contraction

Examples of muscle tonicity includes

- Passive resistance to stretch

- Degree of activation before movement

- Tension or stiffness at rest

Hypotonicity, or low tone, can lead to

Decreased resistance to stretch or flacciddity

Hypertonicity, or high tone, can lead to

- Rigidity

- Spasticity

- Clonus (rhythmic oscillations in response to quick stretch)

What is spasticity

Velocity-dependent resistance to passive muscle stretch

Fluctuating abnormal tone can be seen in disorders with

Abnormal involuntary movements or dyskinesias

Optimal accuracy when measuring muscle tone is at

Midrange of the muscle's length

On the clinical tone scale, a 0 indicates

No tone

On the clinical tone scale, a 1 indicates

Hypotonicity

On the clinical tone scale, a 2 indicates

Normal tone

On the clinical tone scale, a 3 indicates

Moderate hypertonicity

On the clinical tone scale, a 4 indicates

Severe hypertonicity

The contractile elements that contribute to muscle tone are

Myofilaments

The cellular elements that contribute to muscle tone include

- Neural stimulation of calcium release

- Formation of actin and myosin cross-bridges

- ATP use

According to the length-tension relationship, the most cross bridges are formed during

Mid-range of muscle length

Neural contributions to muscle tone includes

- Peripheral inputs

- Spinal cord inputs

- Supraspinal brain center inputs

All neural contributions to muscle tone must work through the

Alpha motor neurons to stimulate muscle fibers to contract

Muscle contraction is dependent on sufficient

Motor unit recruitment

Alpha motor neurons transmits signals from

The CNS to the muscles

Activation of a motor unit depends on the

Sum of excitatory and inhibitory input to the alpha motor neuron

What is a motor unit

All the muscle fibers that are innervated by 1 axon

Dendrites _ stimuli and axons _ stimuli

Receive; conduct

Signals from the dendrites and axons cross synapses via

Neurotransmitters

Depolarization/repolarization are initiated by the

Sodium/potassium pump

Causes of alpha motor neuron damage includes

- Poliomyelitis

- Demyelinating diseases

- Trauma

- Compression

Low muscle tone is due to

Insufficient activation of motor units for holding positions of movement

Decreased alpha motor neuron excitation can be caused by

- Immobilization

- Stroke

- MS

- TBI

What are some potential consequences of abnormal muscle tone and function

1. Difficulty developing adequate force output for normal posture and movement

2. Poor posture

what causes Noxious stimulation, coldness, and stress?

- Guarding due to pain

- Temperature homeostasis

- Perception of threat

High muscle tone is characterized by

Abnormally high excitatory input to intact alpha motor neuron

Regrowth of alpha motor neurons is

Slow and limited in distance (about 1 mm per day)

Spasticity develops

Some time after injury

Fluctuating muscle tone is typically due to _ and can cause _

Basal ganglia; difficulty with muscle control

What is an example of fluctuating muscle tone

Resting tremors that come with Parkinson's disease

What are possible consequences for abnormally high muscle tone

- Discomfort or pain

- Contractures

- Abnormal posture

- Skin breakdown

- Function inhibition

Common restrictions of active motion include

- Muscle weakness

- Abnormal muscle tone

- Pain

- Direction following issues

- Restrictions in ROM

Common restrictions of passive motion includes

- Soft tissue shortening

- Edema

- Adhesion

- Mechanical block

- Spinal disc herniation

- Adverse neural tension

What is physiological motion

Motion of one segment of the body relative to another segment

What is accessory motion

Motion that occurs between joint surfaces during normal physiological motion

Accessory motion can be either

Intraarticular or extraarticular

What is a capsular pattern restriction

A specific combination of motion loss that is caused by shortening of the joint capsule surrounding a joint

Common causes of capsular patterns include

- Effusion

- Fibrosis

- Inflammation with degenerative joint disease

- Arthritis

- Immobilization or acute trauma

What is a noncapsular pattern restriction

Pattern of motion loss that does not follow the capsular pattern

Common causes of noncapsular pattern restriction are

- Ligamentous adhesion

- Internal derangements

- Extra-articular lesions

A ligamentous adhesion limits

Motions in all directions that stretch the adhesion

Internal derangements limits

Motion in directions that compress the fragment

Extra-articular lesions limits

Motion in directions tha stretch or compress the lesion

Contractile tissues limit _ while noncontractile tissue limits _

Active ROM; Passive ROM

What is the difference in the 2 types of edema fluid types

Intraarticular fluid causes capsular type restriction and extraarticular fluid causes a noncapsular type restriction

Contracture, or soft tissue shortening, are primarily caused by

- Immobilization or disuse

- Scarring and fiber cross linking

Adhesion is defined as

Abnormal joining of parts to each other

What are the primary causes of adhesion

- Scarring

- Immobilization

- Disuse

Mechanical blocks are defined as

Bone or fragments of articular cartilage or intraarticular discs/menisci

Primary causes of mechanical block include

- DJD and osteophytes

- Fracture malunion

- AVN

- Trauma

- Disc/meniscal tears