Guillain-Barre Syndrome
What is the etiology of GBS?
-incidence: 1-2/100,000
-peaks in young adults and 50-80 yrs
-more men than women, some seasonal variance
-immune-mediated disease; 2/3 cases have previous acute infection: bacterial (campylobacter), viral (influenza, Epstein-Barr virus, CMV), surgery, rarely vaccinations
What is the etiology of PPS and who does it affect?
- new neuromuscular sxs occur decades (~25 years) after recovery from acute polio
-1/4 to 1/2 of 1.63 million polio survivors will develop PPS
What is the etiology of Myasthenia Gravis? What is the pathogenesis?
-Etiology: autoimmune disorder affecting the neuromuscular junction and motor end plate; risk factors: thymic disorders, diabetes, RA, systemic lupus erythematosus, pregnancy, chronic infections, familail diposition
-pathogenesis: defect of neuromuscular junction, number of acetylcholine receptors is decreased, decreased efficiency of neuromuscular transmission, failure of nerve impulses to cross neuromuscular junction to stimulate muscle contraction
What is the pathogenesis of cerebral palsy and the most common etiology?
-pathogenesis: varies with the etiology (no consistent pathology); on autopsy: hemorrhage, encephalopathy, or malformation of CNS; hypoxic-ischemic injury at birth; bottom line: neurodevelopment doesn't progress normally, brain fails to show normal maturation after injury
-most common etiology: prenatal (80%)- often unknown factors
-other etiologies: perinatal, postnatal, cerebral hemorrhage, anoxia, brain malformations, infections, infections, poor maternal condition, trauma
What is the pathogenesis of GBS? What is the prognosis?
- Pathogenesis: lesions appear throughout PNS, from spinal nerve roots to distal motor and sensory fibers, antibody-mediated demyelination (autoimmune): inflammatory process, demyelination at Nodes of Ranvier, Schwann cells divide and remyelinate nerves
-prognosis: 5% mortality rate; after 1 year: 67% get complete recovery, 20% with remaining deficits; poorer outcomes: older age, longer time before recovery begins, need for mechanical ventilation
What is the pathogenesis of PPS?
-surviving axons innervate many more muscles than originally; weaker systems
-sxs are related to attrition of oversprouting motor neurons that can no longer support these axonal sprouts
-overuse of muscles with < 5/5 strength
What is the clinical presentation of Myasthenia Gravis?
-main feature: weakness and fatigue of skeletal muscles
-85% of cases have generalized, proximal weakness
-spectrum of mild to severe disease (4 major categories): ocular, mild generalized, acute fulminating, late severe
-cranial muscles, especially eyes, show weakness first (diplopia and ptosis)
-weak neck muscles may cause head bobbing
-difficulty with chewing, swallowing, aspiration
What are the key neuromotor and musculoskeletal clinical presentations?
-neuromotor= altered muscle tone and performance: spasticity: 75-85% have spastic CP, poor balance and coordination, uncontrolled movements (dyskinesia), weakness; delayed postural reactions; delayed motor development: impaired muscle performance, decreased ability to learn new movements, all motor functions affected
-musculoskeletal: weakness: use of compensatory strategies, maladaptive changes in muscle tissue; contractures: habitual movement or positioning; bony malalignment: posture and movement, abnormal bone growth; joint instability: hips especially at risk
What are the clinical manifestations of GBS? (course of disease)
-ascending symmetric distal motor weakness and sensory impairments
-paresthesia in toes, distal weakness in LEs
-weakness progresses to trunk, UEs, facial muscles, breathing
-flaccid paralysis with absence of DTR
-"classic form": </= 4 wks from onset to peak impairment
-90% of cases: sxs stop progressing in 4 wks
-static phase of 2-4 wks before recovery
-recovery occurs from proximal to distal
-recovery: months to yrs
What is the clinical presentation and medical management of PPS?
-SxS: declining muscle strength in previously affected muscles, joint pain, muscle atrophy, excessive fatigue
-treatments: treat symptoms, modify lifestyle, surgery to correct deformities
What is the medical management of Myasthenia Gravis?
-increased weakness improvement with rest
-acetylcholinesterase inhibitor
-immunosuppressives
-thymectomy-success in 85% of patients; 35% achieve remission
-plasmapheresis for short-term treatment (controls auto-immune response
What are the 3 types of the most common CP Classification?
-spastic CP is most common: spastic diplegia/diparesis (mainly in LEs- amb with scissoring), spastic hemiplegia/hemiparesis, spastic hemiplegia/quadriparesis- most severe form, affects all limbs, trunk, and face, usually have other developmental disabilities
-dyskinetic CP: muscle tone in limbe changes, making movements difficult
-ataxic CP- difficulty with balance and coordination
-mixed cp- most common is spastic/dyskinetic
What is the treatment of GBS?
-Rx to control the autoimmune respone
-plasmapharesis/plasma exchange (plex)- filters antibodies
-IV immunoglobulin
-mechanical ventilation
-rehabilitation is essential
What is the prognosis of PPS?
-slowly progressive disorder
-stable periods of 3-10 years
-decreased function = decreased QOL
What is the prognosis of Myasthenia Gravis?
-exacerbations and remissions are variable, especially in 1st year
-remissions are rarely permanent
-slowly progressive course
-infections can cause exacerbations
-myasthenic crisis is a medical emergency: respiratory muscle weakness and mechanical ventilation
What are the possible medical interventions for CP? How would you describe the main goal of PT for people with CP?
-pharmacology: decrease tone, Baclofen Pump to deliver meds, botox injections
-surgery: selective dorsal rhizotomy (resecting post roots of spinal cord), orthopedic (support a joint, increase flexibility, maintain alignment)
-PT goal: focus on improving motor control and minimizing musculoskeletal issues with growth
-rehabilitation: activity based interventions with lifestyle modifications and devices to improve mobility (serial casting, orthoses, family-centered care)
What is the PT role in treating patients with GBS?
-early stages: ROM, monitor muscle strength, easy fatigability, avoid complications of immobility, respiratory support, skin care
-recovery stages: active assistive exs, progress to active, then resistive; aquatic therapy; neuromuscular facilitation; assistive devices, orthotics
What is the PT role in treating patients with PPS?
-never exercise to point of fatigue
-monitor vitals for response
-orthoses for stability
What is the PT role in Myasthenia Gravis?
-monitor respiratory function
-treat side effects of corticosteroid
-energy conservation to avoid fatigue
-strength-training with close monitoring for fatigue
-patient/family education
What aspects determine the prognosis of people with CP?
-life expectancy is normal in general; less for quadriplegic CP
-ambulation potential is predicted by motor skill at age 2 yrs (50-60% children can ambulate independently)