GLOSSARY

The insertion is the attachment of a muscle to the bone that usually moves during contraction; in the limbs, it is usually distal and often via a tendon.

Characteristics

• Direction of pull: when the muscle contracts, it pulls the insertion towards the origin.
• Distance from the joint: the distance of the insertion from the joint axis determines the muscle’s moment arm; a more distant attachment produces more force, and a closer one produces more speed and range at the end of the limb.

Structure of the Attachment (Enthesis)

The site where a tendon attaches to bone, the