Neurological Disorders and Motor Systems

Neurological Infective and Degenerative Diseases

• The extrapyramidal and spinocerebellar systems modulate and fine-tune outputs, evaluating and adjusting based on feedback to achieve desired outcomes.
• The cerebellum enables learning and adjustment, together with the cortex.
• The extrapyramidal system influences output from the cortex via feedback loops and instructions to the AHC via reticulo-spinal fibers.

Parkinson's Disease

• Neurodegenerative disease characterized by Lewy body accumulation in areas of the body, resulting in dysfunction.
• Classic degeneration occurs in the Substantia nigra pars compacta.
• Diagnosis involves bradykinesia and at least one of the following: muscular rigidity, 4-6 Hz resting tremor, or postural instability.

Cerebellar Ataxia

• Characterized by incoordination of movement and unsteadiness due to cerebellar dysfunction.
• Clinical examination reveals gait disorder with imbalance, staggering, difficulties with tandem walking, upper-limb and lower-limb dysmetria, and saccadic ocular pursuit.
• Management involves treating the underlying etiology, and symptomatic therapy including physical measures and medications.

Chorea and Ballismus

• Chorea is characterized by irregular, rapid, non-stereotyped, random, and involuntary movement.
• Ballismus is proximal chorea resulting in large amplitude movements.
• Classified according to etiology, and therapy relates to etiology and symptomatic therapy usually involving butoryphenones or antidopaminergics.

Dystonia

• Characterized by involuntary sustained contraction of muscles or groups of muscles resulting in abnormal posture, often associated with a tremor.
• Classified by age of onset, distribution, and other factors.
• Therapy involves botulinum toxin and physical therapy.

UMN and LMN Weakness

• UMN (Upper Motor Neuron) weakness: characterized by increased tone, brisk reflexes, and extensor plantar responses.
• LMN (Lower Motor Neuron) weakness: characterized by reduced tone, reduced or absent reflexes, and wasting of muscles.
• Causes of UMN and LMN weakness include brain lesions, spine lesions, demyelination, and peripheral neuropathy.

Muscular Dystrophies

• Many causes of muscular dystrophy, with pattern of weakness defining the type.
• Examples include Duchenne muscular dystrophy, limb-girdle muscular dystrophy, and congenital myopathy.
• Therapy is usually supportive, involving occupational therapy and physiotherapy.

Infectious Diseases

• Poliomyelitis: inflammation of the grey matter in the spinal cord, usually caused by polio or other viruses.
• AIDP (Guillain-Barré syndrome): acute inflammatory demyelinating polyneuropathy, often preceded by an infection.
• Brain abscess: bacterial or fungal infection of the brain, can be caused by hematogenous or contiguous spread.
• Meningitis: inflammation of the meninges, often caused by bacterial or viral infection.
• Encephalitis: inflammation of the brain tissue, often caused by viral or bacterial infection.