Muscle Strength & Length

Question 1

Objective Assessments

Answer 1

Observation (standing alignment, muscle tone, symmetry)
Functional tests (squatting, hopping, jumping, running etc.)
Active/passive ROM
Muscle strength/length/palpation
Special tests

Question 2

Contradictions to Muscle Testing

Answer 2

• Neurological conditions with spasticity
• Severe cardiac or respiratory disease
• Fracture
• Dislocation
• Myositis ossificans
• Severe infection/inflammation in the muscle or joint
• Malignancy in the region

Question 3

What Does Optimal Muscle Function Require Muscle to be able to do?

Answer 3

• Shorten concentrically (mobility)
• Hold isometrically (postural control)
• Lenghten eccentrically (stability)
• Provide proprioceptive feedback to CNS

Question 4

Isometric Testing

Answer 4

Diagnostic techniques to determine if pain is from contractile (muscle or tendon) or non-contractile structure. If symptoms are reproduced on contraction, suggests muscle or tendon problem.
Not always conclusive due to shearing and compression of inert structures.
No grading system.

Question 5

Isotonic Testing

Answer 5

Measure of the strength of muscles when moving through range of motion. Groups of muscles testing, and if needed, individual muscles.
Grading system.
Strength will depend on age, gender, build, level of physical activity of patient.

Question 6

Interpretation of Resisted Isometric Testing

Answer 6

Strong and pain free: normal response
Strong and painful: minor lesion of muscle and tendon (muscle strain or tendinopathy)
Weak and painful: Severe lesion (fracture, infection, inflammation, severe strain or tendinous lesion)
Weak and pain free: Lesion of nervous system, complete muscle tear or tendon rupture.

Question 7

Isometric Muscle Testing - Components

Answer 7

• Joint positioned in mid-range (where muscle is strongest)
• Build resistance up to maximal over a few seconds (and slowly release)
• Meet strength of patient with your resistance to avoid sudden movements

Question 8

Grading of Isotonic Muscle Testing - MRC Scale

Answer 8

Grade 0: No visible or palpable contraction
Grade 1: Visible or palpable contraction
Grade 2: Full ROM, gravity eliminated (not able to move against gravity.
Grade 3: Full ROM, against gravity
Grade 4: Full ROM against gravity + moderate resistance
Grade 5: Full ROM against gravity + maximal resistance

Question 9

Basic Rules of Isotonic Muscle Testing

Answer 9

1. PATIENT POSITION (comfortable, stable, only 1 joint moving)
2. CHECK UNAFFECTED SIDE FIRST
3. GIVE CLEAR INSTRUCTIONS
4. START WITH GRADE 3!
5. APPLY GRADUAL PRESSURE
6. DOCUMENT CLEARLY

Question 10

When to Stop Manual Resistance

Answer 10

Watch patient’s face for pain reaction

Stop when patient does not resist anymore or experiences too much pain.

Question 11

Muscle Length Testing

Answer 11

Flexibility of muscle.

Stabilizing one end of muscle and slowly and smoothly moving body part to stretch muscle.

Question 12

Which components are noted when doing a muscle length test?

Answer 12

• the quality of movement
• the range of movement
• the presence of resistance ROMovement and at the end of the ROMovement: may identify whether muscle, joint or neural tissues are limiting the movement.
• pain behavior (local and referred) through the range.

Question 13

ROM vs. Muscle Length Testing

Answer 13

Joint ROM depends on:
- Movement available at joint (ROM of ligament, capsule)
- Length of muscles crossing the joint
One joint muscle length = Joint ROM
2 joint muscle length < Joint ROM (other joint can limit ROM because of its positioning).

Question 14

Position for Muscle Length Testing

Answer 14

• Muscle should be in elongated position
• Muscle should be isolated as far as possible (testing one single muscle)
• Bony landmarks used for measurement tools should be palpable
• Motion should not be blocked by external objects (like pillows/bed)
• Patient should be able to move into the starting position themselves (otherwise not safe)