12/06/2020 INTRODUCTION TO CLASSIFICATION Dianne Zeller 2020 1 Objectives • Introduce and familiarise participants with commonly used and current Classification systems 2 Classification • The act or process of dividing things into groups according to their type • Classifying children with Cerebral Palsy according to their type of CP 3 12/06/2020 Why do we Classify? • Common language • To assist in treatment planning • To help predict potential abilities and possible associated problems • For research –for consistency and comparisons across groups of children with CP • Epidemiology • To plan current and future service needs • Evaluation of change over time 4 Difficulties with classification • CP is an umbrella term for a heterogeneous groups of disorders • The clinical picture changes • The terminology is confusing • Classification systems have different purposes 5 Classification systems can be based on: • Subtype –quality and distribution of tone • Functional abilities • Pathology • THERE IS NO UNIVERSAL CLASSIFICATION SYSTEM 6 12/06/2020 Current Classification Systems • Bobath/NDT Classification System • SCPE: Surveillance of Cerebral Palsy in Europe • Washington Workshop: 7 Bobath NDT Classification System Based on Quality of Tone and Distribution • 4 Main Groups 1. Spastic Hypertonia-Always increased tone in one or more limbs • Quadriplegia, Diplegia, Hemiplegia • Mild, Moderate, Severe 2. Dyskinaesia- Presence of excess or unwanted movement • Dystonic • Chore-Athetosis • Pure Athetosis 3. Ataxia- Generalised hypotonia with cerebellar signs 4. Hypotonia 8 Continuum of tone Spastic hypertonicity-Always above normal Severe Hypertonia Moderate Mild Pure Choreo Normal Mild Moderate Dystonia with Hypotonia Severe Dystonic spasticity 9 12/06/2020 SCPE: Surveillance of Cerebral Palsy in Europe • Established in Europe in 1998- in 8 European countries • Establish a data base • Monitor specific trends • Provide information for service planning • Collaborative research 10 SCPE Definition of CP (2000) • Cerebral Palsy (CP) is a group of disorders involving movement and posture and of motor function; it is permanent, but not unchanging; it is due to a non- progressive interference, lesion, or abnormality of the developing/immature brain. (SCPE, Dev Med Child Neurol 42 (2000) 816-824) 11 Classification tree of Cerebral Palsy Sub types SCPE classification(Cans C., (2000) DMCN, 42: 816-824) 12 12/06/2020 SCPE Classification(Cans C., (2000) DMCN, 42: 816- 824) • Bilateral Spastic • Unilateral • Dystonic-hypokinesia, hypertonia Dyskinetic • Choreoathetotic-hyperkinesia, hypotonia Ataxic 13 Classification: Clinical subtype Quality of Tone • Hypertonia: • Hypotonia • Fluctuating, varies through a wide range Anatomical distribution • Bilateral- Previously known as Quadruplegia/Diplegia • Hemiplegia-Unilateral • * 14 Spastic Hypertonia Is there persisting increased muscle tone in one or more limbs Y Are both sides of the body involved Y N Spastic Bilateral Spastic Unilateral Spastic CP is characterized by at least two of the following : Abnormal pattern of posture and/or movement Increased tone (not necessarily constant) Pathological reflexes (increased reflexes; hyperreflexia and / or pyramidal signs eg. Babinski response) 15 12/06/2020 Hypertonia- • Tone is defined as “resistance to passive stretch while the patient is attempting to maintain a relaxed state of muscle activity”. It reflects the state of active muscle contraction • Hypertonia is defined as “abnormally increased resistance to externally imposed movement about a joint”. Sanger et al., (2003) Pediatrics 111: 89) • It is measured at rest or during involuntary movement but not on voluntary muscle contraction 16 Hypertonia vs spasticity • Are they the same thing? • Hypertonia has 2 components: • Neural component: Spasticity • Non neural component: Muscle properties, Joint capsule restrictions • The presence of spasticity suggests the presence of hypertonia(Sanger, (2003)) 17 Hypertonia, Upper Motor Neurone Syndrome and Spasticity: Clinical Management and Neurophysiology , Johnson et al 2001 Neural related, eg spasticity Upper motor neuron Increased resistance to syndrome passive movement Non neural related e.g changes in muscle, mechanical properties Figure 1. Neural and non neural mechanisms contributing to increased resistance to passive motion in an upper motor neuron syndrome 18 12/06/2020 Hypertonia • May be caused by spasticity, dystonia, rigidity, or a combination of features Spastic Dystonic Hypertonia Hypertonia Rigid Hypertonia Classification and Definition of Disorders Causing Hypertonia in Childhood Terence D. Sanger, et al Pediatrics, 2003;111;e89, DOI: 10.1542/peds.111.1.e89 19 Spastic Hypertonia. Predominant Lesion in the Brain: Cortex and Corticospinal tracts 20 Theory of Spasticity The exaggeration of the stretch reflex in patients with spasticity could be produced by two factors. 1. An increased excitability of muscle spindles. In this case, passive muscle stretch in a patient with spasticity would induce a greater activation of spindle afferents with respect to that induced in a normal subject, of course considering a similar velocity and amplitude of passive displacements. 2. The second factor is an abnormal processing of sensory inputs from muscle spindles in the spinal cord, leading to an excessive reflex activation of 훼-motoneurons. 21 12/06/2020 22 Definition of Spasticity The pathophysiology of spasticity, G. Sheean, European Journal of Neurology 2002, 9 (Suppl. 1): 3–9 Spasticity ……….is a form of hypertonia due to a velocity-dependent increase in tonic stretch reflexes, which results from abnormal spinal processing of proprioceptive input. Velocity dependent: Resistance increases as speed of lengthening increases • Tested using Ashworth , Tardieu • R1: Range at which a catch is felt when moving the limb quickly • R2 Range at which a catch is felt when moving a limb slowly 23 24 12/06/2020 Dyskinetic CP Is there persisting increased muscle tone in one or more limbs? N Is the tone varying? Y N Dyskinetic CP Unclassifiable Reduced activity-Tone Increased activity –Tone tends to be increased tends to be decreased Dystonic CP Choreo-athetotic CP 25 Dyskinetic CP is dominated by both : Abnormal pattern of posture and/or movement Involuntary, uncontrolled, recurring, occasionally stereotyped movements 26 Predominant lesion in the Brain- Basal Ganglia Basal ganglia are strongly interconnected with the cerebral cortex, thalamus, and brainstem, as well as several other brain areas. The basal ganglia are associated with a variety of functions, including control of voluntary motor movements, procedural learning, habit learning, eye movements, cognition, and emotion. 27 12/06/2020 Dystonia • A movement disorder in which involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures, or both (Sanger et al., 2009) • . 28 Sanger article……. • Dystonia could potentially cause hyperkinetic movements by inserting dystonic postures that result in movement of a part of the body away from the intended position. • If sustained dystonic postures are inserted in voluntary movements, this could result in the prevention of movement, substitution of an unwanted posture for an intended posture, or slow movement in an attempt to overcome the inserted dystonic posture. • Thus in our definitions, dystonia is characterized by one or more repeated postures. Chorea is characterized by multiple repeated but not rhythmic movements. Athetosis is characterized by nonrhythmic movements without intervening postures. 29 Dystonic CP Reduced activity (Hypokinesia), tone tends to be increased( Hypertonia) 30 12/06/2020 Choreo-Athetotic CP • Chorea is distinguished from dystonia due to the apparently random, unpredictable, and continuously ongoing nature of the movements, compared with the more predictable and stereotyped movements or postures of dystonia. • Athetosis involves continuous smooth movements that appear random and are not composed of recognizable sub-movements or movement fragments. The term “athetosis” derives from the Greek meaning “without position or place,” reflecting the inability to maintain a stable posture • Chorea is characterized by multiple repeated but not rhythmic movements. Athetosis is characterized by non-rhythmic movements without intervening postures. 31 Choreo-athetotic CP Increased activity (Hyperkinesia); tone tends to be decreased (Hypotonia) 32 Ataxia • Is there persisting increased muscle tone in one or more limbs N Is the tone varying? Is there generalised hypotonia with signs of ataxia? Y N Ataxia Unclassifiable 33 12/06/2020 Ataxia • The term “Ataxia” is derived from Greek word meaning ‘lack of order’ • “Ataxia” is defined as an inability to generate a normal or expected voluntary movement trajectory that cannot be attributed to weakness or involuntary muscle activity about the affected joints (Sanger et al, 2003) • Mismatch between intention and action Ataxic CP is characterized by both : Abnormal pattern of posture and / or movement Loss of orderly muscular coordination so that movements are performed with abnormal force, rhythm and accuracy 34 Main body of cerebellum- 3 functional areas Functional area Function Indication of dysfunction Vestibulocerebellum Equilibrium Cannot control eye movements Postural control/movement during head rotation and when Reciprocal innervation standing and walking. (agonist/antagonist) Wide base of support (Low Anticipatory correction COG) Eye movements Inefficient balance