Children with Hypertonia

1. Children with Hypertonia

2. What is Cerebral Palsy (CP)? • A group of disorders impacting the development of movement and posture • Results in activity limitation • Accompanied by disturbances of: • Sensation • Cognition • Communication • Perception • Possibly behavior and/or seizure disorder (Campbell S 2000, Miller F 2005, Bax M 2005 )

3. What is Cerebral Palsy (CP)? • Caused by a non-progressive defect or lesion occurring in an immature brain • Insult occurs before or after birth • Single or multiple locations (Campbell S 2000, Miller F 2005, Bax M 2005 )

4. Categories of CP • Spastic or Hypertonic CP • Hemiplegia • Diplegia • Quadriplegia • Ataxia • Athetosis • Hypotonia

5. M R Franjoine & M P Haynes + Domains- Dimensions NDT Enablement Classification Model of Health and Disability From: NDT Approach Theoretical Foundations & Principles of Clinical Practice, Table 2.1 pg. 82

6. M R Franjoine & M P Haynes + Domains- Dimensions NDT Enablement Classification Model of Health and Disability From: NDT Approach Theoretical Foundations & Principles of Clinical Practice, Table 2.1 pg. 82

7. Body Structure and Functions • Spastic Diplegia 41.5 • Spastic Hemiplegia 36.4% • Dyskinesia or Athetosis 10% • Spastic Quadriplegia 7.3% • Ataxia 5% (Campbell S 2000)

8. Body Structure and Functions • Lesion(s) impacts: • the motor cortex and/or • white matter projections to and from cortical sensorimotor areas of the brain Causes: • Unknown prenatal condition • Asphyxia • Prematurity • Intracranial bleeds, infection, medical conditions (Campbell S 2000)

9. Body Structure and Functions • Cognition • Neuromuscular System • Sensory System • Musculoskeletal System • Regulatory • Gastrointestinal • Cardiopulmonary • Integumentary

10. Cognition VARIABLE CHILD BY CHILD Dependent on: • Lesion(s) • Secondary effects of various systems • Seizures • Access to environment

11. Neuromuscular System What is muscle “tone”? • Amount of tension in a resting muscle • Resists being lengthened • Has neural components • Has mechanical and elastic components; muscle and connective tissue (Lundy-Ekman 2002, Kandel 2000)

12. Neuromuscular System What is Hypertonicity? • Abnormally high resting tension • An abnormally high resistance to being lengthened • Still has both neural and mechanical components • The tonic component of hypertonus (Crenna 1998, Lundy-Ekman 2002, Kandel 2000)

13. Neuromuscular System What is Spasticity? • Resistance to rapid muscle stretch • Velocity dependent • The phasic component of hypertonus • Often associated with: • Upper Motor Neuron Syndrome (UMNS) • Hyperactive deep tendon reflexes • Clonus (Kandel 2000)

14. Neuromuscular System --Primary Impairments • Impaired Muscle Activation Excessive Co-activation • Impaired Muscle Synergies • Inability to Initiate, Sustain, Terminate

15. Typical • Co-activation • Simultaneous activation of agonists and antagonists at a joint influencing movement in the same plane • Normally used to increase joint stability or for proximal stability to support precise distal movements • Allows for graded movement

16. Atypical • Excessive Co-activation • Decreases movement speed • Limits flexibility of movement responses • Increased energy costs and fatigue

17. Child Picture

18. Typical • Muscle Synergies • A group of muscles working together across multiple joints and organized to act as a functional unit • Simplifies the work of the CNS • Strengthens with repetition

19. Atypical • Impaired Muscle Synergies • Based on limited movement repertoires • Difficult to vary or adapt to meet the requirements of different tasks • Produces stereotypical movement patterns

20. Atypical • Impaired Muscle Synergies • Movements are limited in amount and frequency • Movements tend to be in more limited ranges

21. Child Picture

22. Typical • Initiate, Sustain, Terminate • Quick response of muscles to the decision to move • Easily maintain posture against gravity • Relax muscles • Quick response of muscles to the decision to cease movement

23. Atypical • Difficulty with Initiate, Sustain, Terminate • Delay between desire to activate and ability to initiate muscular movement (latency) • Difficulty holding against gravity…especially postural muscles • Can’t turn off muscles in time

24. Child Picture

25. Neuromuscular System • Impaired Motor Execution • Impaired Modulation and Scaling of Forces • Impaired Timing and Sequencing • Excessive overflow of Intra-Interlimb contractions

26. Typical • Modulation and Scaling of Forces • Controlled acceleration or deceleration • Using the proper amount of force • Constant balancing of agonists and antagonists during movement

27. Atypical • Impaired Modulation and Scaling of Forces • Inability to slow down as they approach a target • Reduces accuracy (overshoots) • Particular difficulties grading grip

28. Child Picture

29. Typical • Timing and Sequencing

30. Atypical • Impaired Timing and Sequencing • Unable to turn on and off muscles or patterns of muscles at the appropriate times • i.e. agonist and antagonist coordination • i.e. the hamstrings during gait • Incorrect sequence of activation for a task

31. Child Picture

32. Typical • Overflow of Intra-Interlimb contractions • When learning a new skill • With increased effort • Within a limb or elsewhere in the body • Decreases as proficiency is gained • Can be actively overridden

33. Atypical • Excessive overflow of Intra-Interlimb contractions • Bobaths described “associated movements” • i.e. while grasping with one arm, will posture with the other • i.e. when flexing the hip, the ankle dorsiflexes • Occur at times similar to typical but with a generally lower threshold • Decreases the capacity for isolated control during effort

34. Child Picture

35. Neuromuscular System • Impaired Force Generation • Strength: the ability to contract a muscle to a sufficient degree to impact the task • Can be masked by tone and spasticity • Primary—impaired input from motor pathways • Secondary– atrophy and resultant fiber type and connective tissue changes • Postural • Movement system

36. Child Picture

37. Neuromuscular System • Anticipatory Postural Control • TYPICAL: • Postural set prior to initiating a task or movement • ATYPICAL: • Posture is not linked to movement • Fail to anticipate postural needs prior to a movement or task • Fail to generate adequate proximal posture for distal function

38. Child Picture

39. Neuromuscular System • Poverty of Movement • TYPICAL: • Large variety of movement repertoires to chose from • Can easily adapt and modify repertoires for the task • Movements are fluid, flexible, and complex • ATYPICAL: • Movement repertoires are limited in number • “Stereotypic” • Repertoires are difficult to change • Adapt poorly to various tasks

40. Neuromuscular System • Fractionated or Dissociated Movements • TYPICAL: • “Isolated movement” or “dissociated movement” • ATYPICAL: • Difficulty isolating movement • Segment to segment • Inter-limb • Intra-limb • Limbs from trunk

41. Child Picture

42. Sensory System Vision • Vestibular • Somatosensory

43. Vision • Varies greatly • Cortical blindness to refractory errors • Strabismus (eyes not properly aligned) • Esotropia (the eye turns in) • Exotropia (the eye turns out) • Nystagmus • Visual tracking problems • Field cuts

44. Vision • Ghasia, Brunstrom, Gordon & Tychsen, 2008 • GMFCS levels I and II • Similar to typically developing children • Strabismus • Amblyopia (lazy eye) • GMFCS levels III to V • More severe deficits • Deficits not observed in typically developing children i.e. dyskinetic strabismus and Cerebral Visual Impairment

45. Vestibular • Difficult to separate from vision and postural control • More impact seen in SQ than SD

46. Somatosensory • Clearly atypical yet difficult to truly assess • Propioception • Kinesthetic awareness • 2 point discrimination • Stereognosis

47. Sensory Processing • “ the ability of the nervous system to perceive, interpret, modulate, and organize sensory input for use in generating or adapting motor responses… (Miller & Lane 2000)

48. Musculoskeletal System • Considerable secondary impairments • Bone: • Boney deformities 2° atypical muscle pull • Decreased bone density of long bones (FX)

49. Musculoskeletal System • Considerable secondary impairments • Dislocations: • 2° to atypical muscle pull and atypical bone shape formation • Impacts many joints from jaw to foot • Scoliosis and rib cage deformities

50. Musculoskeletal System • Considerable secondary impairments • Muscle: • Shortening and contracture • Fiber type shift • Weakness • Connective tissue: • Increased stiffness due to atypical matrix within muscle • Over-lengthening or shortening of tendons