Week 2 (Weakness and Strength Tests)

Question 1

Weakness and loss of muscle strength result from

Answer 1

1. Decreased voluntary drive

2. Decreased muscle cross sectional area / atrophy

Question 2

What are the 4 grades of weakness and what does each mean?

Answer 2

1. Paralysed: no activity in muscle or ability to contract a force
2. Very weak: some strength but profoundly weak
3. Weak: muscles are working but not against resistance
4. Strong: can work against resistance

Question 3

Define concentric, eccentric isometric

Answer 3

Concentric: muscle develops force by muscle shortening
Eccentric: still developing force while muscle tendon unit is lengthening
Isometric: developing force but muscle length isn’t changing

Question 4

What does changing the resistance force moment/lever arm do

Answer 4

• Changes exercise intensity
• Importance of location of external force, joint angle, patient position
• Changes assessment/measurement

Question 5

Types of measurement

Answer 5

• Isometric
• Dynamic
• Functional vs non-functional

Question 6

Manual muscle testing grades

Answer 6

0. No observable or palpable muscle contraction
1. Observable or palpable muscle contraction but no movement
2. Full ROM not against gravity
3. Full ROM against gravity
4. Full ROM with some manual resistance through range against gravity
5. Full ROM with full manual resistance through range against gravity

Question 7

What grades are manual muscle testing useful for

Answer 7

Grades 0-3

Not reliable and becomes subjective after grade 3

Question 8

Types of hand-held dynamometer tests

Answer 8

Make test: requires measuring instrument be held still while subject contracts maximally against it
Break test: requires subject keep their joint still while tester applies an increasing load

Question 9

How to set up RM testing

Answer 9

• Standardise body position for subject
• Adequate warm up and rest periods
• Avoid compensatory movements
• Minimise number of tests to avoid fatigue
• MUST FAIL

Question 10

How to increase reliability of tests

Answer 10

Standardise

• Point of application of force (lever arm): direction of force on the moment arm changes the exercise intensity
• Joint angle: whether at beginning, midpoint or end range changes the muscle and moment arm length
• Maximal effort: standardise verbal encouragement

Question 11

Advantages and disadvantages of RM testing

Answer 11

Advantages:
- Multiple muscle groups can be tested
- Can be used for testing and training
- Provides measure of dynamic strength
Disadvantages:
- Not good for weak population
- Strength is limited by weakest point in ROM

Question 12

Advantages and disadvantages of dynamometry

Answer 12

Advantages:
- Emphasis at a specific point in ROM
- Easy to use and portable
Disadvantage:
- can't convert data to functional activities 
- less functional to ADLs

Question 13

Advantages and disadvantages of MMT

Answer 13

Advantages
- Good for paralysed patients
Disadvantages
- Subjective after grade 3