Biomechanics & Gait Analysis Flashcards

A patient presents with an antalgic gait pattern. Which characteristic best identifies this gait deviation?

Answer: Shortened stance phase on the painful limb

Antalgic gait is characterized by a shortened stance phase on the painful limb because the patient minimizes the time spent bearing weight on the affected side.

What gait deviation is most directly caused by insufficient ankle dorsiflexion (foot equinus)?

Answer: Early heel rise and knee hyperextension in stance

Foot equinus prevents the tibia from advancing over the foot during midstance, causing early heel rise and compensatory knee hyperextension to maintain forward progression.

Which orthotic intervention is most appropriate for a patient with excessive rearfoot pronation during gait?

Answer: Medial heel wedge with rearfoot post

A medial heel wedge combined with a rearfoot post controls excessive subtalar eversion (pronation) by applying a varus moment to the calcaneus during stance.

The Trendelenburg sign is positive when which finding is observed during single-limb stance?

Answer: The pelvis drops on the swing limb side

A positive Trendelenburg sign occurs when the pelvis drops on the swing limb side due to weakness of the hip abductors (primarily gluteus medius) on the stance limb side.

What is the primary purpose of the metatarsal bar in orthotic device design related to gait biomechanics?

Answer: Transfer weight-bearing stress proximal to the metatarsal heads

A metatarsal bar transfers weight-bearing forces proximal to the metatarsal heads, reducing pressure and pain at the metatarsophalangeal joints during the push-off phase of gait.

During normal walking, ground reaction force peaks at approximately how many times body weight?

Answer: 1.1–1.2 times body weight

During normal level walking, ground reaction force peaks at approximately 1.1–1.2 times body weight, occurring during loading response and terminal stance.

Steppage gait is a compensatory mechanism for which underlying deficit?

Answer: Foot drop due to weak or absent ankle dorsiflexion

Steppage gait — characterized by exaggerated hip and knee flexion during swing phase — compensates for foot drop (inability to dorsiflex the ankle), preventing the toes from catching the ground.