Atypical development

Question 1

What is the dynamic systems theory?

Answer 1

Holistic approach to understanding human motor development

Includes various body systems and social environment, physical environment, and psychological environment

Question 2

List the characteristics of atypical development

Answer 2

Abnormal tone – hypotonia, hypertonia, fluctuations, rigidity​

Exaggerated, prolonged reflex behavior​

Absence of normal reflexes​

Lack of variability, variety, and frequency of spontaneous movement​

Lack of adaptability

Lack of antigravity control​

Lack of dissociation, rotation​

Flexion and extension are not balanced​

Persistence of asymmetry​

Lack of controlled weight shifts​

Lack of elongation on weight bearing side with lateral flexion on non-weight bearing side

Poor proximal stability with decreased ability to move against gravity​

Prolonged fixing or limiting degrees of freedom due to poor underlying control​

Abnormal postural alignment​

Poor coordination and control of movement

Question 3

What are positive signs for motor disorder diagnosis?

Answer 3

lead to increased frequency or magnitude of muscle activity, movement, or movement patterns

Examples: ​

Hypertonia​

Chorea​

Tics​

Tremor

Question 4

What are negative signs for motor disorder diagnosis?

Answer 4

insufficient muscle activity or insufficient control of muscle activity

Examples:​

Weakness​

Impaired selective motor control​

Ataxia​

Apraxia

Question 5

In addition to positive and negative signs, what else can contribute to reduced function?

Answer 5

sensory deficits, biomechanical limitations, abnormalities of posture and balance, cognitive deficits, learning disabilities, fatigue, and decreased motivation​

And, of course, the environment!

Question 6

Explain weakness in context of a negative sign:

Answer 6

insufficient muscle activation, inability to generate normal voluntary force in a muscle or normal voluntary torque about a joint​

Assessed during attempts to generate force in a single joint at one point in time

Question 7

What are some different causes of weakness?

Answer 7

many possible causes of weakness​

Weakness may be caused by dysfunction in many different parts of the neuralaxis including the cerebrum, corticospinal and bulbospinal tracts, spinal cord, lower motor neurons, neuromuscular junction, or contractile elements of muscle​

With chronic weakness there may be changes in passive and active muscle properties that either perpetuate or partially counteract the weakness

Question 8

more weakness continued… (2)

Answer 8

Normally weakness is manifest in many different postures, movements, or tasks​

However, weakness may only be evident for certain joint angles, speeds of movement, or postures of other joints​

Ability to generate force may deteriorate as a result of early fatigue of muscles, reduced endurance, or an inability to generate a sufficiently rapid increase in force

Question 9

more weakness continued.. (3)

Answer 9

In presence of significant contractures or other limitations of ROM it may not be possible to identify weakness​

hard to tell how much kid is trying and hard to test strength with contracture

It may not be possible to establish the level of effort exerted by the child​

May not be able to test in presence of cognitive deficits or psychiatric disorders​

In very young child, weakness is one possible cause of hypotonia and hypotonia may be the only clinically evident sign of weakness in a young or uncooperative child

Question 10

what is reduced selective motor control?

Answer 10

Defined as the impaired ability to isolate the activation of muscles in a selected pattern in response to demands of a voluntary posture or movement​

“Muscles in a selected pattern”: simultaneous activity level of each muscle in a group of muscles in which certain muscles may be activated while others are relaxed

Question 11

What happens to cause impaired ability to have selective motor control?

Answer 11

the expected pattern is not achieved either due to excessive activation of muscles that would be expected to be relaxed or inability to activate muscles that would be expected to be active

Question 12

Reduced selective motor control notes continued (2)

Answer 12

When reduced selective motor control involves decreased muscle activation, then particular muscles may be unable to generate full force when they are part of the abnormal pattern of activity​

This is distinguished from weakness if the muscles are able to generate full force in other contexts​

When weakness is present, it may not be possible to determine if a deficit of selective motor control exists

Question 13

Reduced selective motor control notes continued (3)

Answer 13

Examples: activation of knee and hip flexors muscles when a child attempts to dorsiflex the ankle​

These patterns are sometimes referred to as “obligate synergies”​

Reduced selective motor control may manifest as abnormal postures or unusual movement patterns​

Example: the child may have to adduct the shoulder in order to generate sufficient elbow extension force

Question 14

What is ataxia?

Answer 14

Definition: inability to generate a normal or expected voluntary movement trajectory that cannot be attributed to weakness or involuntary muscle activity about the affected joints​

“Trajectory” is a series of positions or joint angles over time​

In some cases, may lead to decreased accuracy

Question 15

Continued notes about ataxia (2)

Answer 15

May be present in multiple parts of the body​

Leads to disorders of gait, limb, or trunk control​

It may also occur only during certain types of movement​

For example, there may be greater abnormality for multijoint movements or greater deficits of rhythmic movements​

Deficits are not specific to particular tasks or goals

Question 16

Continued notes about ataxia (3)

Answer 16

Specific deficits that may be seen as components of ataxia include:​

Dysmetria (inaccurate motion to a target) ​

Dyssynergia (decomposition of multijoint movements)​

Dysdiadochokinesia (lack of rhythmicity)

Question 17

Continued notes about ataxia (4)

Answer 17

Associated with increased movement variability (think of gait)​

Intention tremor​

Examples: failure to adjust trunk musculature before or during reaching may lead to postural instability and poor reaching​

Often associated with injury to cerebellum​

Can also be seen in the context of peripheral sensory loss

Question 18

What is apraxia and developmental dyspraxia ?

Answer 18

Apraxia: impaired ability to accomplish previously learned and performed complex motor actions that is not explained by ataxia, reduced selective motor control, weakness, or involuntary motor activity​

B. Developmental Dyspraxia: failure to have ever acquired the ability to perform age-appropriate complex motor actions that is not explained by the presence of inadequate demonstration or practice, ataxia, reduced selective motor control, weakness or involuntary motor activity

Question 19

Apraxia and developmental dyspraxia notes continued (2)

Answer 19

“Impaired ability” means that the motor acts are performed in a manner that is awkward, slow, or fails to accomplish the desired goal​

“Complex motor actions” refers to actions that may have multiple components and are associated with goal oriented task performance, tool use, or gestures

putting movements together is hard for them

Question 20

What are some other negative signs in childhood?

Answer 20

Deficits in sensory function including tactile, kinesthetic, or proprioceptive sensation​

Sensory information and attention are needed to correct for errors during movement and to determine errors in the outcome​

Deficits in higher-order sensory function may impair the ability to determine spatial relationships between objects and therefore can interfere with tool use, bimanual coordination or task planning

Question 21

What is neglect?

Answer 21

Neglect may lead to inadequate effort and thus can be a cause of weakness​

Neglect may also lead to inadequate practice or self observation and thereby slow learning of complex tasks​

“Learned nonuse” or “developmental disregard”

Question 22

What is a soft sign?

Answer 22

may not mean anything, but may point towards possible problems with neurologic system

Refers to a group of functional neurological findings which are general and not focal, often subtle, and may relate to faulty integration in abnormal development​

They may give clues to underlying poor organization and possible CNS deficit

Question 23

What are some behavioral soft signs in early diagnosis of neuromotor dysfunction?

Answer 23

Manifest early​

Sucking, swallowing, and feeding abnormalities​

Colic​

Persistent irritability​

Demanding behavior​

Continuous gross movement and activity

Markedly limited attention span​

Delayed speech with poor or repetitive expression​

Withdrawn and isolated behavior​

Irregular sleep habits​

Repetitive movements