Tendon rupture is a break in the continuity of a tendon, and tendonitis is a sterile inflammatory condition caused by long-term chronic strain. The difference lies in the different causes, symptoms and complications. 1. Different causes: tendon rupture is often caused by trauma, such as falls, strains and other reasons, resulting in tendon rupture, but also may be due to long-term use of a tendon, resulting in severe wear and tear of the tendon, and ultimately rupture. Tendonitis, on the other hand, is an aseptic inflammation caused by long-term chronic strain such as overuse of muscles and tendons. 2. Symptoms are different: the symptoms of tendon rupture are mainly manifested as obvious pain, localized swelling, loss of function at the tendon rupture site, and severe limitation of activities. Tendonitis is mainly characterized by pain, tenderness, dysfunction and inflammation. 3. Different complications: with tendon rupture, complications such as joint stiffness and adhesion may occur. If there is no timely exercise, it will lead to the joints being in a state for a long time, the local blood circulation becomes poor, the joints become stiff, and the exudate will lead to tissue adhesion. With tendonitis, complications such as muscle atrophy and tendon sheath stenosis may occur. Tendonitis causes pain, swelling, and numbness in the affected area, resulting in dysfunction of the joint movement of the affected limb, reduced muscle activity, and muscle atrophy. If associated tendon discomfort occurs, it is recommended that you seek prompt medical attention and follow your doctor’s instructions.