OT1172 Neuro Reading Summary for Tues. Feb. 22, 2005

OT1172 Neuro Reading Summary for Tues. Feb. 22, 2005

By Ahuva Katzman & Jenny Kim

Schoen, S. & Anderson, J. (1993). Neurodevelopmental Treatment frame of reference (pp. 46-49). In P. Kramer & J Hinojosa (Eds.) Frames of reference for pediatric occupational therapy. Baltimore, MD: Williams and Wilkins.

-Neurodevelopmental treatment (NDT)= a sensorimotor approach widely used by OT’s in tx of neuromuscular disorders  sensory motor techniques are applied to remediate the neurological and developmental sequelae of dysfunction.

HISTORY

-NDT originally dev’d and used in tx of neurologically impaired children, primarily those dx with cerebral palsy (CP)

-an early focus = to decrease muscle tone thru use of reflex inhibiting postures (RIP), postures opposite to primitive reflex patterns typically assumed by child  later, hierarchical motor sequences into therapy were used, with one activity following another during facilitation next phase of NDT emphasized facilitation of automatic movement sequences as opposed to isolated developmental skills

-most current phase of NDT recognizes need for tx to be directed towards specific functional situations  thru use of facilitation techniques, child should be able engage in functional and meaningful activities  present approach focuses on facilitation of normal movement patterns for functional activities

THEORETICAL BASE FOR NDT

-according to this frame of reference, normal development is divided into four basic categories:

1. Principles of Normal Motor Development

-general principles of normal motor development dictate control precedes from cephalo to caudal, proximal to distal, and gross to fine  these principles provide guide for the determination and sequencing of intervention

2. Sensory-Motor-Sensory Feedback

-developmentally, most movement is preceded by a sensory experience  a resulting motor response provides sensory feedback from the proprioceptors in the muscles and joints used to accomplish a specific movement  the initial sensory stimulus can be an internal event, an external event, or a combination of both

3. Components of Normal Development

a) Interplay between Stability and Mobility

-can be understood most effectively by defining dynamic movement, which refers to smooth, controlled, coordinated action based on a point of stability as its support  the part of the body in contact with the support surface can function as the point of stability

-mobility is then achieved through a weight shift in any direction  NDT assumes that normal movement requires the combination of stability and mobility  each body part can perform both a stabilizing and mobilizing function, depending on the activity

b)Effects of Postural Reflex Mechanism on Movement

–assumes postural reflex mechanism provides the foundation for the qualitative aspects of normal movement

-postural tones= provides background tone for normal movement and determines the muscle quality in overall patterns and distribution throughout the body rather than in specific muscles  normal postural tone must be low enough to allow movement against gravity (mobility) yet high enough to maintain a stable position against gravity (stability)  mature distribution of postural tone is reflected in greater tone proximally and lower tone distally

-reciprocal innervation = interplay between agonist and antagonist muscles during coordinated muscle activity

-righting and equilibrium reactions= two automatic movement patterns that occur during the first year of development and persist throughout life  righting reactions restore and maintain the vertical position of the head in space, the alignment of the head and trunk, and the alignment of the trunk and limbs

-postural alignment=a term often used to describe the presence of mature righting reactions  equilibrium reactions build on already developing righting reactions, and they serve to maintain or regain balance during a shift in the center of gravity

c)Ability to Dissociate Movements

– dissociation (the ability to differentiate movements between the various parts of the body) is indicative of maturation of the CNS  dissociation of movement occurs in normal development within the first year of life and is characterized by separate movements between the segments of the body

d) Development of Postural Control in the Three Planes of Space

-developmentally, motor control occurs first in sagittal plane (extension and flexion against gravity)  next phase is in frontal plane (lateral righting)  final phase in transverse plane (rotation)

-in this frame of reference  most significant developmental postures are prone, supine, sidelying, sitting, quadruped, kneeling, and standing

4. Sequences in Motor Development

-NDT assumes motor dev’t occurs sequentially with the sequences overlapping also assumes that previously developed skills prepare child for later behaviours  while baby is mastering a specific motor skill, he already is experimenting with the components in the subsequent stage

VARIETY OF MOVEMENT

-in normal dev’t, infants show a variety of motor patterns when moving in and out of developmental positions and when interacting with objects

ABNORMAL MOTOR DEVELOPMENT

-abnormal dev’t can be viewed in several ways

-Bly (1980)  abnormal dev’t occurs in ‘blocks’ in the neck, shoulder girdle, pelvis, and hips

-Bobaths (1975, 1971)  abnormal dev’t described as a lack of cortical inhibition that results from a damaged or immature nervous system  emphasized importance of abnormal postural tone combined with gradual appearance of tonic reflex activity, as causing abnormal patterns of posture and movement

- may also be seen as the persistence of primitive reflexes or as compensatory attempts to gain anti-gravity control  both views characterized by stereotypical patterns of movement the cycle then moves from compensation to habit, resulting in changes in muscle length, that over time may cause orthopaedic limitations in movement.

-problems in postural tone are assumed to have a significant impact on the development of abnormal movement patterns in this frame of reference

-lack of dissociation may also result in abnormal movement  often characterized by total patterns of movement, referred to as associated responses

SENSORY INPUT AS A MEANS OF BRINGING ABOUT CHANGE

-may be done thru therapist’s use of various techniques referred to as handling (=when the therapist uses her hands on child in a specified manner, using graded sensory input at key points of control)

-key points of control= specific areas on child’s body selected for therapeutic handling  key points of control may be proximal or distal

-thru handling, therapist elicits and facilitates motor responses

FUNCTION/DYSFUNCTION CONTINUA

-provide therapists with descriptions of observable behaviours that are clinically relevant and that identify function and dysfunction in children

Postural Tone

-normal postural tone allows person move against gravity with mobility and ease

-postural tone may be abnormally high resulting in excessive stability and difficulty moving against gravity

-postural tone may be abnormally low, resulting in excessibe mobility and lack of control of movement

-fluctuations in postural tone are also possible

- dysfunctions in postural tone can also be reflected in pattern of distribution  normal tone is lower distally  in dysfunction tone is higher distally than proximally

(refer to chart on p. 60)

Stability/Mobility

-Normal child: combines stability and mobility when weightshifting and moving from one position to another. (i.e. child who is able to maintain sitting and then weightshift to the side to reach for a toy).

-child who lacks stability uses compensations- the use of the skeletal system rather than the neuromuscular system to achieve stability. (i.e. the use of a posture with a broad base of support such as the hips marked in external rotation and abduction or “W” sitting, or high guard posturing of the arms)

Reciprocal Innervations as it Relates to Controlled Coordinated Movement

-Normal child: has controlled coordinated mvmt throughout the full range of motion when moving. Reciprocal innervation allows this to occur through interplay between agonist and antagonist muscle groups and coordinated mvmt involves the timing, sequence, and rhythm of mvmt.

-Child with low/fluctuating tone (athetosis)- uses extremes of the ranges of motion and has difficulty controlling mvmt in the mid range.

Child with high tone (spasticity) uses mid range of motion and has difficulty in achieving full range of mvmt.

Righting and Equilibrium Reactions as They Relate to Postural Alignment

-a lack of postural alignment is considered dysfunctional

-behaviours indicative of dysfunction: excessive pull into flexion in upright positions, predominance of head hyperextension, inability to elongate muscles on weightbearing side of body, asymmetry

Dissociation

-the ability to differentiate mvmts among various parts of the body

-mvmt patterns performed in an associated or synergistic way are indicative of dysfunction

-behaviours indicative of function: to roll with rotation between shoulders and pelvis, the ability to use reciprocal leg mvmts in crawling etc.

-behaviours indicative of dysfunction: log rolling, bunny hopping etc.

Variety of Movement

-in normal development infants show a variety of motor patterns

behaviours indicative of dysfunction: stereotypically, one or both lower extremities persist with extension, adduction, internal rotation in all positions, stereotypically one or both upper extremities persist with shoulder elevation and retraction in all positions

-children restricted by abnormal tone and stereotypical mvmt patterns may develop contractures an deformities.