Musculoskeletal Consequences of SCI (exam 2) Flashcards
Mechanisms of bone loss
Imbalance of formation and resorption
Loss of leading and normal pull of muscles
Kidney resorbs and excretes large amount of CA in blood
When does the decline in bone production happen?
Rapid decline in first two years
Greatest loss in first 6 months
Chronic and slow loss after
How does the bone change?
Cortical thinning and decreased trabecular bone
What bone is not impacted or only minimally impacted?
Spine!
Most common fracture site?
Distal femur and proximal tibia
When do most fractures occur?
During non traumatic events
Name at least 3 complications of fractures
Pressure ulcers
Altered position in WC
Respiratory illness
UTI
AD
Spasticity
Delirium
Mortality
Decreased functional mobility and independence
Muscle complications/cascade after an SCI
Neuromuscular junction degeneration
Fat deposition (smaller muscle)
Protein degradation
Macrophage type 2 becomes type 1
Insulin resistance
Muscle fibers become more fast twitch
Muscle cells apoptosis
Why is the switch from slow twitch to fast twitch fibers not ideal?
Muscle gets faster (and smaller) but also fatigues faster
What is the direct result from a reduced amount of anabolic hormones?
Muscle atrophy followed by reduced energy expenditure
What happens when we get more energy in than we’re putting out?
Increased adiposity!
Intramuscular adipose doubles
Increase in visual adipose tissue
How do determine if someone is obese after an SCI
Fat mass over 20% (impacts 66% of chronic SCI patients)
BMI and waist circumference under estimate obesity
What does obesity increase the risk of?
Hyperglycemia
Dyslipidemia (high cholesterol)
Diabetes (50% of the population)
What are the components of metabolic syndrome and what can it lead too?
Hyperglycemia
Dyslipidemia
Abdominal obesity
Hypertension
Can lead to cardiovascular disease
What is the primary cause of death in chronic SCI patients?
Cardiovascular disease
How can electrical stimulation help mitigate musculoskeletal impacts of SCI?
Used for strengthening
Primarily can help with body composition (muscle and fat) and metabolism
Can also help with bone, pulmonary, spasticity, function and quality of life
Contraindications/precautions for electrical stimulation
Bone density/fracture history
Pacemaker
Uncontrolled AD
Uncontrolled hyper/hypotension
Open skin
Thrombosis
Pregnancy
Cancer
ROM limits that impact activity
Types of NMES that is studied to have benefits
Resistance training
Cycling
Rowing
Changes in cardiovascular and metabolism from electrical stimulation
Increased glucose uptake pathways
Decreased intra-muscular fat
Improved CV and metabolic outcomes
Changes in bone from electrical stimulation
Requires 6-12 months to make changes but there is some evidence for prevention of BMD decline and reversal of bone mineral loss
Dosing is critical and needs:
Strong viable contractions
Resistance
At least 1 year of intervention
Key takeaways from electrical simulation for patients with SCI
Greater effects on muscles than bone
Loading and dosing is important
A strong viable contraction must be elicited!
Changes in fibers and fatigability from electrical stimulation
Increase VO2
Increased amount of type 2a fibers (fast oxidative) and decreased type 2b (fast glycolytic)
Reversal of loss in the fatigue index after training
