Skip Navigation

Fulcrum

Last Updated: Feb 10, 2015

Displayed on other page

A fulcrum is the mechanical principle that gives our bodies (particularly our limbs) their great strength. Connections between joints, called synovial joints, are fulcrums, the bones they connect are levers, and the muscles attached to them apply force (or resistance). An example of a first-class lever is the joint between the skull and the atlas vertebrae of the spine: the spine is the fulcrum acrossmycontentbreak which muscles lift the head. An example of a second-class lever is the Achilles tendon, pushing or pulling across the heel of the foot. A third-class lever might be the elbow joint: when lifting a book, the elbow joint is the fulcrum across which the biceps muscle performs the work.