Which muscle is classically associated with a 'foot slap' gait?

Which muscle is classically associated with a 'foot slap' gait?

• A. Tibialis anterior
• B. Gastrocnemius
• C. Soleus
• D. Peroneus longus

Answer: (A)

Foot slap gait reflects weakness of the ankle dorsiflexors, especially the tibialis anterior. Normally, as the heel contacts the ground, the tibialis anterior contracts eccentrically to dorsiflex the ankle and control plantarflexion, producing a smooth heel strike. When this muscle is weak, the foot cannot dorsiflex promptly, so it rapidly plantarflexes and the forefoot slaps onto the ground. This pattern is typical of dorsiflexor (tibialis anterior) weakness, such as from damage to the deep peroneal nerve. The other muscles listed are plantarflexors or evertors, whose weakness would cause different gait changes rather than a foot slap.

Foot slap gait reflects weakness of the ankle dorsiflexors, especially the tibialis anterior. Normally, as the heel contacts the ground, the tibialis anterior contracts eccentrically to dorsiflex the ankle and control plantarflexion, producing a smooth heel strike. When this muscle is weak, the foot cannot dorsiflex promptly, so it rapidly plantarflexes and the forefoot slaps onto the ground. This pattern is typical of dorsiflexor (tibialis anterior) weakness, such as from damage to the deep peroneal nerve. The other muscles listed are plantarflexors or evertors, whose weakness would cause different gait changes rather than a foot slap.