Tendons?

Tendons themselves are cords of tough, fibrous connective tissue that attach muscles to bones. Tendonitis is an inflammation of the tendon. The condition may also involve the tendon sheath usually occurring close to where the tendon goes into the muscle.
Tendons are generally healthy structures that appear glistening white to the naked eye. If you've ever carved a turkey, the tendons are the tough bands you cut through to get the drumsticks apart.