COF COF Neuromuscular Conditions & Orthotics 2 — Questions and Answers
Question 1: An AFO fabricated with a plantarflexion stop and free dorsiflexion is most appropriate for a patient with:
- Spastic hemiplegia with equinus tendency (Correct answer)
- Flaccid foot drop with intact dorsiflexors
- Mild ligamentous laxity
- Plantar fasciitis
Correct answer: Spastic hemiplegia with equinus tendency
A plantarflexion stop prevents the foot from dropping into equinus during swing while allowing dorsiflexion during stance, which is ideal for managing spastic equinus in hemiplegia.
Question 2: What is the recommended orthotic management for a patient with a complete C6 spinal cord injury who has preserved wrist extension?
- No orthosis needed
- TLSO for trunk support
- Wrist-driven flexor hinge orthosis (tenodesis splint) (Correct answer)
- Bilateral KAFOs
Correct answer: Wrist-driven flexor hinge orthosis (tenodesis splint)
A wrist-driven flexor hinge orthosis uses preserved wrist extension to create a functional three-jaw-chuck pinch grip for C6 SCI patients through the tenodesis effect.
Question 3: In a patient with L3–L4 spinal cord injury, which orthotic option best facilitates community ambulation?
- Bilateral solid ankle AFOs
- Bilateral KAFOs (Correct answer)
- Hip-knee-ankle-foot orthoses (HKAFOs)
- No orthosis needed
Correct answer: Bilateral KAFOs
An L3–L4 SCI preserves hip flexors and quadriceps but lacks ankle dorsiflexors and reliable knee stability, requiring bilateral KAFOs for functional ambulation.
Question 4: A stroke patient with spastic hemiplegia develops genu recurvatum (knee hyperextension) during stance. The most appropriate AFO modification is:
- Free plantarflexion stop
- Set the ankle trim line in slight dorsiflexion (Correct answer)
- Switch to a carbon fiber posterior leaf spring
- Increase the medial flange height
Correct answer: Set the ankle trim line in slight dorsiflexion
Setting the AFO ankle in slight dorsiflexion creates an anterior tibial moment (knee flexion moment) during stance, counteracting hyperextension of the knee.
Question 5: When prescribing orthoses for a patient with myasthenia gravis, what is the most critical design consideration?
- Maximum rigidity and durability
- Minimal weight to reduce energy expenditure in fatigable muscles (Correct answer)
- Dynamic resistance to strengthen affected muscles
- High-profile design for maximum support
Correct answer: Minimal weight to reduce energy expenditure in fatigable muscles
Myasthenia gravis causes fatigable weakness; lightweight orthoses minimize the additional muscular effort required for ambulation, conserving the patient's limited energy reserves.
Question 6: Which gait deviation caused by foot drop is directly corrected by an AFO with a dorsiflexion assist spring?
- Trendelenburg gait
- Steppage gait (Correct answer)
- Scissor gait
- Antalgic gait
Correct answer: Steppage gait
A dorsiflexion assist spring lifts the foot during swing phase, eliminating the compensatory high-stepping (steppage) pattern used to clear a dropped foot.
COF COF Neuromuscular Conditions & Orthotics 2
An AFO fabricated with a plantarflexion stop and free dorsiflexion is most appropriate for a patient with: