Cerebellar Lesions Lecture 3.2 PDF

ATAXIA Lecture 3.2 (1.5 hours)  ATAXIA May be due to lesion in Vestibular apparatus Cerebellum Peripheral sensory mechanisms (sensory ataxia)  TYPES OF ATAXIA Cerebellar eg stroke, MS, head injury, alcohol abuse, vitamin deficiency Sens...

ATAXIA Lecture 3.2 (1.5 hours)  ATAXIA May be due to lesion in Vestibular apparatus Cerebellum Peripheral sensory mechanisms (sensory ataxia)  TYPES OF ATAXIA Cerebellar eg stroke, MS, head injury, alcohol abuse, vitamin deficiency Sensory eg peripheral neuropathy, GBS, partial spinal cord injury (dorsal columns) Vestibular eg infection, tumour  DIAGNOSIS OF ATAXIA Medical history, family history, neurological symptoms Urine and blood examination Genetic testing MRI  WHAT IS ATAXIA? General term to describe abnormal coordination of voluntary movements Errors of Rate Amplitude Accuracy Force (NOT weakness)  ROLE OF THE CEREBELLUM Initiation and control of voluntary movement Timing of movement/muscle action Moment-to-moment correction of errors Compensating for lesions of cerebral cortex Motor learning and adaptive adjustments  FUNCTIONAL REGIONS OF THE CEREBELLUM Vestibulocerebellum (flocculonodular lobe) Balance & eye movements Spino cerebellum (central part of anterior and posterior lobes, including vermis & intermediate part of hemispheres) Ongoing execution of limb movt, error correction Cerebro cerebellum (lateral parts of cerebellum) Preparation of movement, feedforward role in modulating cortical motor outputs  CEREBELLAR LESIONS Damage to midline structures (vermis & flocculonodular lobe) Truncal ataxia Damage to hemisphere structures Symptoms ipsilateral to side of lesion  CEREBELLAR ATAXIA Clinical signs of cerebellar lesions Neurological diseases resulting in ataxia Functional implications of ataxia Physiotherapy assessment of ataxia Principles of physiotherapy treatment  CEREBELLAR ATAXIA Lesion of UMN system Hyper reflexia Predominantly motor (afferent input via spinocerebellar pathways transmit subconscious proprioception info used esp for balance)  CEREBELLAR ATAXIA Dysmetria Rebound phenomenon Dysdiadochokinesia Intentional tremor Dyssynergia Hypotonia  FEATURES OF ATAXIA Dysmetria – inaccurate amplitude of movement and misplaced force (hypometria – undershooting; hypermetria – overshooting)  ATAXIC MOVEMENT Adaptive motor behaviour Proximal stabilisation to permit distal function Fixing with upper limbs in sit/stand Wide base of support in sit/stand/gait  FEATURES OF ATAXIA Rebound phenomenon – dysfunction in agonist/antagonist relationship; inability to ‘brake’ movement Dysdiadochokinesia – difficulty performing rapid alternating movements (RAM) a) Delay in initiation of movement b) Dysmetria, with intention tremor as hand nears the nose c) Dysdiadochokinesia Fig 9.2 Carr & Shepherd  OFTEN PRESENT WITH ATAXIA: Tremor – intention (not at rest); also see in postural muscles (titubation) when sitting or standing still Dyssynergia – decomposition of movement Dysarthria Nystagmus  FEATURES OF ATAXIA Hypotonia Historically described as ‘Reduced resistance to passive movement’ ? Due to loss of dynamic spindle response ? Due to decrease in phasic motor cortex neuronal discharge (? Whether it really exists – may just be loss of reinforcement that cerebellum usually provides to cortical output)  FUNCTIONAL PROBLEMS Reduced coordination of functional movements eg rolling, bridging, reach and grasp Reduced postural stability eg poor sitting and standing balance, unsteady gait, frequent falls  DIFFICULTY DECELERATIN G WHEN ASKED TO STOP WALKING Fig 9.4 Carr & Shepherd  Need for distal stability in order to coordinate fine motor function Fig 9.7 Carr & Shepherd  Need for distal stability in order to coordinate fine motor function Fig 9.8 Carr & Shepherd  C AUSE OF CEREBELLAR ATAXIA Paediatric or early adult onset Spinocerebellar ataxia (group of degenerative disorders manifested by progressive ataxia) Friedrich’s ataxia (inherited ataxia; degeneration of spinal cord and cerebellum; cerebrum relatively spared) 50% - unknown cause 26YO MALE, CAN’T STAND UP WITHOUT SWAYING, R SIDED ATAXIA  Dependence on upper limbs for proximal stability, wide BOS Fig 9.9 Carr & Shepherd  PHYSIOTHERAPY ASSESSMENT Assessment of primary movement disorders as result of lesion Assessment of adaptive motor behaviour Eg ask patient to stand up from chair – physio notes that patient has wide BOS and pushes with UL (adaptive changes). Physio then asks patient to repeat task, this time with normal BOS and no UL assist (observe primary movement disorder)  PRINCIPLES OF PHYSIOTHERAPY INTERVENTION Will vary dependent upon whether patient has ataxia due to Degenerative/progressive condition eg MS Reversible condition eg cerebellar stroke https://www.hopkinsmedicine.org/health/conditions-and- diseases/ataxia (14.39) exercises for ataxia – general principles and pl watch it before the practical session  PRINCIPLES OF PHYSIOTHERAPY INTERVENTION Strategies to build up proximal control and core stability Strengthening program LET’S GLANCE THE SELF-STUDY DOCUMENT ATTACHED AS 4.2.2 Rehabilitation and Cerebellar Ataxia By Prof Jon Marsden School of Health Professions University of Plymouth 2017 PRINCIPLES OF PHYSIOTHERAPY INTERVENTION Train control during performance of functional tasks & modified independence Use external constraints for steadiness if necessary Provide practice controlling agonist/antagonist Train actions that require sustained force as well as actions that require burst of force Train actions that involve varying degrees of postural adjustments Enable practice of open and closed tasks for development of predictive timing  PRINCIPLES OF PHYSIOTHERAPY INTERVENTION Activities may include Stop & start Fast & slow Low resistance/high resistance Low accuracy demand/high accuracy demand Single task/dual task Low postural demand/high postural demand Predictable movement/unpredictable movement Simple, safe and focus on the quality of exercises  EFFIC ACY OF INTERVENTION Paucity of research in this area Motor skill learning is possible in those with cerebellar dysfunction Requires multiple repetitions for skill acquisition of complex task such as reaching accuracy eg 100+ trials* *  OUTCOME MEASURES Qualitative Handwriting, video footage Quantitative Eg finger-nose counts, heel-shin counts, CTSIB, 10 metre walk test, falls/week, 9 hole peg test Standardised or informal Impairment, function or participation based Eg International cooperative ataxia rating scale (ICARS), Barthel Index, SF 36  INTERNATIONAL COOPERATIVE ATAXIA RATING SCALE (ICARS) Utilises traditionally known tests such as the finger-to-nose, heel-to-shin, walking, drawing, speech and oculomotor movements tests with qualitative analysis. A reliable and repeatable measure of ataxia Will be covered in the practical session this week  SUMMARY Ataxia describes abnormal coordination of movement Ataxia may result from lesions in the cerebellum, vestibular system or sensory systems Errors of rate, accuracy, amplitude and force may occur Physiotherapy intervention will be dependent upon whether lesion is stable (reversible) or progressive (degenerative)