Which orthosis might be used to assist with crouched gait due to plantar flexor weakness?

• A. AFO
• B. SMO
• C. FO
• D. KAFO

Answer: (A)

An ankle-foot orthosis is the most appropriate choice because it provides stability and control at the ankle, which is exactly what is needed when plantar flexors are weak. With plantar flexor weakness, the ankle tends to plantarflex and the leg may compensate by bending the knee and hip going into a crouched gait. An AFO holds the ankle in a neutral or slight dorsiflexed position, supporting the tibia to progress over the foot, improving foot clearance during swing, and reducing the knee and hip crouch. It stabilizes the foot during stance and can be solid or articulated to match the walking needs. Other devices either don’t control the ankle adequately (FO), are too mild for this issue (SMO), or include knee control beyond what’s needed (KAFO), making the AFO the best fit here.