The Hip: Preservation, Replacement and Revision Tracking Pixel
Duke Orthopaedics
presents
Wheeless' Textbook of Orthopaedics

Windlass Mechanism



- Discussion:
    - great toe provides stability to the medial aspect of the foot thru Windlass mechanism of the plantar aponeurosis;
           - plantar aponeurosis arises adjacent to  tubercle of calcaneus and inserts into the base of the proximal phalanx;
           - as body passes over foot, the proximal phalax slides over metatarsal head, which in turn depresses the first metatarsal;
    - in hallux valgus, this stabilization mechanism is disrupted because of lateral subluxation of MP joint;
           - windlass mechanism becoems musch less effective, both in depressing metatarsal head and in the wt transfer to the hallux itself & w/ result of creating transfer metatarsalgia;
           - removal of the base of the proximal phalanx of the hallus (Keller) disrupts the windlass mechanism and transfers weight to the second metatarsal head;
    - osteotomy that shortens first metatarsal more than 7-10 mm or results in dorsiflexion of first metatarsal likewise results in decreased wt bearing and hence wt transfer to lateral side of the foot



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, September 4, 2012 1:49 pm