DPM Clinical Biomechanics 2

Question 1

During the contact phase of gait, which muscle group acts eccentrically to control the rate of pronation?

Accepted Answer

Tibialis posterior

Answer

The tibialis posterior decelerates subtalar joint pronation eccentrically during the contact phase of gait.

Question 2

What is the functional significance of the angle of gait (toe-out angle) averaging approximately 7 degrees?

Accepted Answer

It aligns the foot with the line of progression to optimize lever arm efficiency

Answer

A 7-degree toe-out angle aligns the foot's propulsive axis with the line of progression, optimizing the lever arm for push-off.

Question 3

The windlass mechanism is most dependent on which anatomical structure becoming taut?

Accepted Answer

Plantar fascia

Answer

Dorsiflexion of the hallux tightens the plantar fascia, elevating the medial longitudinal arch via the windlass mechanism.

Question 4

In Root's neutral position casting technique, the subtalar joint is held at what position?

Accepted Answer

Neutral — one-third of total range from supination

Answer

Root's technique defines subtalar neutral as the position one-third of total range from full supination (or two-thirds from full pronation).

Question 5

Which forefoot deformity involves the plane of the metatarsal heads being inverted relative to the rearfoot when the subtalar joint is in neutral?

Accepted Answer

Forefoot varus

Answer

Forefoot varus is defined as inversion of the forefoot relative to the rearfoot when the subtalar joint is in neutral position.

(DPM) Doctor of Podiatric Medicine Practice Test