- Active muscle contraction, not the passive windlass mechanism, is the foot’s primary source of rigidity for push-off during walking.
BACKGROUND & OBJECTIVE
The windlass mechanism is considered an important contributor to the function of the foot by stiffening the foot for more effective leverage for push-off during gait. Originally described by Hicks (1), metatarsophalangeal joint extension winds the plantar aponeurosis around the metatarsal heads, pulling the calcaneus towards the phalanges, shortening and raising the arch.
This description models the plantar aponeurosis as a stiff/rigid tie between the calcaneus and proximal phalanges. Yet other work describes the elastic stretch and recoil of the plantar aponeurosis as a natural foot spring mechanism for energy efficiency (2), and another recent study has highlighted contributions of the plantar intrinsic muscles to push-off power (3).
The aim of this study was to explore the interplay between the windlass mechanism, plantar intrinsic foot muscle activation, and ankle plantar flexor activation in relation to gait.
Therapeutic exercises that promote activation and/or aim to strengthen the plantar intrinsic muscles may be beneficial in the prevention and management of plantar heel pain.
Two experiments were conducted to test how the foot is tensioned during contact with the ground. Activation of the ankle plantar flexors (soleus) and plantar intrinsic muscles (abductor hallucis and flexor digitorum brevis) was recorded. Ankle and metatarsophalangeal joint moments