The Windlass Mechanism of the Plantar fascia. What is a Windlass anyway?
After yesterdays post, we thought we might provide more insight to the Windlass mechanism and low and behold; we found AN ENTIRE PAPER on it! Wow, were we thrilled since there is not a ton of decent stuff out on this topic (yes, we are a little geeky, but then again so are you if you are reading this !).
A Windlass is the tightening of a rope or cable around a pivot point. The plantar fascia acts like a cable between the calcaneus and its distal insertion into the proximal phalanyx at the metatarsal phalangeal joints. When the toes are dorsiflexed (as in forefoot rocker from yesterdays post, see bottom diagram above), the heel and toes SHOULD become approximated, as the plantar fascia shortens from its winding around the metatarsal head, contributing to supination of the foot.
To be accurate, this concept of the Windlass mechanism is quite complex because the dorsiflexion of the great toe also shortens the length of the flexor hallucis brevis. And we know that the sesamoid bones under the big toe are embedded in its tendon. Their repositioning as the Windlass engages will drive the sesamoids under the metatarsal, elevating it, and shift this joints eccentric axis. But this is a complex story and post better left for another day. Simply put, this is a complex joint, do not let anyone fool you otherwise. Don’t beleive us ? Ask any bunion (or God forbid a fusion) surgery patient how they are doing. You will get the point then.
Here’s the link to the article (we know you want to read it ! )
The Windlass Mechanism. Just another fascinating foot fact from The Gait Guys.