APMLE Biomechanics and Orthopedics Flashcards

Which term describes a foot type with an elevated medial longitudinal arch and associated equinus contracture?

Answer: Pes cavus

Pes cavus is characterized by an elevated medial longitudinal arch and is often associated with equinus and digital contractures.

In the swing phase of gait, which muscle group is responsible for foot clearance via ankle dorsiflexion?

Answer: Anterior compartment muscles (tibialis anterior, EHL, EDL)

The anterior compartment muscles dorsiflex the ankle during swing phase to ensure foot clearance from the ground.

What is the primary deforming force in a hallux valgus deformity?

Answer: Lateral pull of the adductor hallucis and FHB lateral head

The adductor hallucis and lateral head of FHB create a lateral deforming force that is central to the progression of hallux valgus.

Which radiographic angle is used to assess the severity of hallux valgus and has a normal value of less than 15°?

Answer: Hallux abductus angle (HAA)

The hallux abductus angle (HAA) measures the angular relationship between the first metatarsal and the proximal phalanx, with normal values less than 15°.

Which gait abnormality is characterized by excessive hip hiking and circumduction to achieve foot clearance?

Answer: Steppage gait compensation for foot drop

Steppage gait (hip hiking and circumduction) is a compensation for foot drop caused by anterior compartment weakness.

What is the function of the plantar fascia during the propulsive phase of gait?

Answer: Windlass mechanism that raises the arch and supinates the foot

The windlass mechanism of the plantar fascia is activated during toe dorsiflexion in propulsion, raising the arch and supinating the foot for rigid propulsion.