PCE Clinical Knowledge and Theory 2 — Questions and Answers
Question 1: Which dermatome corresponds to sensation over the lateral aspect of the foot and little toe?
- L4
- L5
- S1 (Correct answer)
- S2
Correct answer: S1
The S1 dermatome supplies the lateral foot, little toe, and posterior calf.
Question 2: A patient presents with a positive Thomas test. Which structure is most likely shortened?
- Hamstrings
- Hip flexors (iliopsoas) (Correct answer)
- Hip external rotators
- Tensor fascia latae
Correct answer: Hip flexors (iliopsoas)
The Thomas test assesses iliopsoas (hip flexor) flexibility; a positive result indicates hip flexor tightness causing the tested hip to flex off the table.
Question 3: Which type of muscle fiber is primarily recruited during high-intensity, short-duration activities such as sprinting?
- Type I (slow-twitch)
- Type IIa (fast oxidative)
- Type IIx (fast glycolytic) (Correct answer)
- Type III (intermediate)
Correct answer: Type IIx (fast glycolytic)
Type IIx fibers have the highest contraction speed and rely on anaerobic glycolysis, making them dominant in maximal short-burst efforts.
Question 4: The resting membrane potential of a typical neuron is approximately:
- -55 mV
- -70 mV (Correct answer)
- -90 mV
- -110 mV
Correct answer: -70 mV
The resting membrane potential of most neurons is approximately -70 mV, maintained mainly by the sodium-potassium ATPase pump.
Question 5: During which phase of gait does the gluteus medius primarily contract to prevent contralateral pelvic drop?
- Initial contact
- Mid-stance (Correct answer)
- Terminal stance
- Pre-swing
Correct answer: Mid-stance
Gluteus medius fires eccentrically during mid-stance to stabilize the pelvis and prevent a Trendelenburg drop on the opposite side.
Question 6: The Neer impingement sign is produced by:
- Passive horizontal adduction with the shoulder at 90° flexion
- Passive internal rotation of the shoulder with the elbow at 90°
- Passive forward flexion of the internally rotated arm (Correct answer)
- Active abduction against resistance at 90°
Correct answer: Passive forward flexion of the internally rotated arm
The Neer sign compresses supraspinatus and subacromial structures by passively forward-flexing the internally rotated arm, reproducing impingement pain.
Question 7: Which law states that bone remodels in response to the mechanical stresses placed upon it?
- Laplace's law
- Wolff's law (Correct answer)
- Starling's law
- Hooke's law
Correct answer: Wolff's law
Wolff's law describes how bone density and architecture adapt to loading, forming along lines of mechanical stress.
PCE Clinical Knowledge and Theory 2
Which dermatome corresponds to sensation over the lateral aspect of the foot and little toe?