Which pattern describes lower limb spasticity in CNS lesions?

Which pattern describes lower limb spasticity in CNS lesions?

• A. Knee extension
• B. Knee flexion
• C. Ankle dorsiflexion
• D. Hip abduction

Answer: (C)

In CNS lesions, spasticity often shows up as stereotyped synergy patterns in the lower limb. The flexor (or knee–ankle) synergy is characterized by hip flexion with external rotation, knee flexion, and ankle dorsiflexion. Ankle dorsiflexion is a key part of that pattern, so it best describes the typical way the lower limb moves when spasticity is present. Knee extension represents the extensor component of a different synergy, and hip abduction isn’t a defining part of the classic lower-limb spastic pattern.

In CNS lesions, spasticity often shows up as stereotyped synergy patterns in the lower limb. The flexor (or knee–ankle) synergy is characterized by hip flexion with external rotation, knee flexion, and ankle dorsiflexion. Ankle dorsiflexion is a key part of that pattern, so it best describes the typical way the lower limb moves when spasticity is present. Knee extension represents the extensor component of a different synergy, and hip abduction isn’t a defining part of the classic lower-limb spastic pattern.