CFO Biomechanics & Gait Analysis 2 — Questions and Answers
Question 1: A patient presents with an antalgic gait pattern. Which characteristic best identifies this gait deviation?
- Shortened swing phase on the painful limb
- Shortened stance phase on the painful limb (Correct answer)
- Increased cadence with normal step length
- Exaggerated arm swing on the affected side
Correct 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.
Question 2: What gait deviation is most directly caused by insufficient ankle dorsiflexion (foot equinus)?
- Trendelenburg gait
- Steppage gait
- Early heel rise and knee hyperextension in stance (Correct answer)
- Circumduction of the contralateral limb
Correct 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.
Question 3: Which orthotic intervention is most appropriate for a patient with excessive rearfoot pronation during gait?
- Lateral heel wedge
- Medial heel wedge with rearfoot post (Correct answer)
- Metatarsal pad
- Forefoot valgus wedge
Correct 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.
Question 4: The Trendelenburg sign is positive when which finding is observed during single-limb stance?
- The pelvis drops on the stance limb side
- The pelvis drops on the swing limb side (Correct answer)
- The trunk leans over the stance limb
- The knee flexes excessively during loading
Correct 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.
Question 5: What is the primary purpose of the metatarsal bar in orthotic device design related to gait biomechanics?
- Transfer weight-bearing stress proximal to the metatarsal heads (Correct answer)
- Increase push-off power at the forefoot
- Correct hallux valgus deformity
- Limit subtalar inversion
Correct 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.
Question 6: During normal walking, ground reaction force peaks at approximately how many times body weight?
- 0.5–0.8 times body weight
- 1.1–1.2 times body weight (Correct answer)
- 1.5–2.0 times body weight
- 2.5–3.0 times body weight
Correct 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.
Question 7: Steppage gait is a compensatory mechanism for which underlying deficit?
- Hip extensor weakness
- Knee flexion contracture
- Foot drop due to weak or absent ankle dorsiflexion (Correct answer)
- Excessive ankle plantarflexion strength
Correct 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.
CFO Biomechanics & Gait Analysis 2
A patient presents with an antalgic gait pattern.
Which characteristic best identifies this gait deviation?