Myasthenia Gravis is a neuromuscular disease causing fluctuating muscle weakness and fatigue due to a breakdown in communication between nerves and muscles. There is no cure, but treatment can relieve symptoms. Signs include weakness of specific muscles like eyes and throat, as well as limbs, worsened by exertion and stress. Physical therapy focuses on aerobic exercise, strength training, swimming, posture, and breathing to build functional capacity and decrease fatigue while avoiding overexertion that worsens symptoms. The goal is improved mobility, balance, and ability to perform daily activities.

1. Myasthenia Gravis

2. Introduction
• Myasthenia gravis (MG) is a neuromuscular
disease that leads to fluctuating muscle
weakness and fatigue
• Caused by a breakdown in the normal
communication between nerves and muscles
• There is no cure for myasthenia gravis, but
treatment can help relieve signs and
symptoms

3. Signs and symptoms
• Initial complaint is a specific muscle weakness
• Extraocular muscle weakness or ptosis
• Bulbar muscle weakness is also common,
along with weakness of head extension and
flexion
• Limb weakness may be more severe
proximally than distally
• Weakness is typically least severe in the
morning and worsens as the day progresses

4. • Weakness is increased by exertion and
alleviated by rest
• Weakness progresses from mild to more
severe over weeks or months, with
exacerbations and remissions
• About 87% of patients have generalized
disease within 13 months after onset
• Difficulty breathing, chewing, swallowing

6. • Factors that worsen MG symptoms :
– Fatigue
– Illness
– Stress
– Extreme heat
– Some medications (chloroquine, procaine, lithium,
phenytoin, beta-blockers, procainamide, statins)

7. Diagnosis
• Neurological examination
• Edrophonium test
• Ice pack test
• Blood analysis
• Repetitive nerve stimulation
• Single-fiber electromyography (EMG)
• Pulmonary function tests

8. Treatment
• Cholinesterase inhibitors
• Corticosteroids
• Immunosuppressant
• Plasmapheresis
• Intravenous immunoglobulin (IVIG)
• Surgery

9. Physical
Rehabilitation

10. Introduction
• MG symptoms tend to progress over time,
usually reaching their worst within a few years
after the onset of the disease
• Muscle weakness caused by MG worsens as
the affected muscles are used repeatedly,
therefore symptoms usually improve with rest

11. Factors limiting daily physical
function in stable MG
• Neuromuscular fatigue
• Low CV fitness levels (20% below normal)
• Diminished physiological fitness reserve (high
energy cost of walking at peak fitness level)
• Percent body fat 2-X normal (45%) and poor
fitness contribute to mobility disability

14. Potential benefits of physical
therapy in MG
• Weight reduction
• Decrease in risk of hypertension, diabetes,
cholesterol
• Decrease in risk of cardiac diseases
• Decrease in risk of osteoporosis
• Mood elevation ; improve cognitive function
• Enhance baseline functional capacity,
improved mechanical efficiency

15. Management Strategy
• There is a lot of variance between patients with
MG
• No one exercise program is same and treatment
strategies may vary
• Evaluation-
– Strength
– Flexibility
– Mobility
– Balance
– Gait

17. Exercise Goals
• Enhance ability to function daily
• Decrease risk of falling
• Completion of functional tasks and
maintenance of independence
• Smoothness and coordination of activities
• Once MG is stable, consistent exercise will
elevate baseline functional capacity which will
diminish the effect of MG exarcebation

18. Exercise Considerations
• The dollar per day rule
• Exercise at the best time of day
• Exercise at peak dose of medication
(pyridostigmine)
• Exercise large, proximal muscle groups for
short periods of time building up only to
moderate intensity
• Do not exceed moderate intensity exercise
level

19. Moderate Exercise Intensity
• HR should not elevate greater than 30 bpm from
resting baseline
• Patient should not become short of breath at
peak of exercising
• MG symptoms should not become worse during
exercise (drooping of eyes)
• Patient should not be tires after 2 hours of
exercise
• Patient should not have severe residual muscle
soreness the day post exercise

20. Types of Exercise used in MG
• Aerobic Exercises
• Strength exercises
• Swimming
• Postural exercise
• Breathing exercise

22. • Strength Exercise –
– Should be done progressively
– Range of motion (flexibility) to light resistance to
full resistance
– Start with lower prescription : 3 sets of 5 reps
– If significant weakness is present, active assist
exercises may be necessary (therapist help)
• The primary goal of therapy is to build the
individual's strength to facilitate return to
work and activities of daily living
• Do not overdo resistive training to the point of
fatigue

25. • Swimming
– Patients should swim in water where they can
touch the bottom
– Deep water is dangerous and may cause patient to
over exert

26. • Postural Exercises-
– Important in assisting with breathing, speaking
and swallowing
– Keeps bones and joints in the correct alignment so
that muscles are being used properly
– Prevents fatigue because muscles are being used
more efficiently, allowing the body to use less
energy

28. • Breathing exercises -
– Help improve lung function
– Include inspiratory muscle training
• Pursed lip breathing
• Diaphragmatic breathing
– These exercises can improve respiratory
endurance as many people with MG have affected
respiratory muscles

31. Reference
• http://www.myastheniagravis.org/
• Myasthenia Gravis foundation of America
http://www.myasthenia.org/
• http://www.mdguidelines.com/
• http://www.pivotalphysio.com/
• http://www.livestrong.com/