Which condition involves inflammation of a tendon due to repetitive stress?

Tendinitis is characterized by inflammation of a tendon, often resulting from repetitive stress or overuse injuries. This condition occurs when the tendon, which connects muscle to bone, becomes irritated or inflamed due to actions that involve frequent movement or strain. Such activities can lead to microscopic tears in the tendon, causing pain, swelling, and reduced mobility.

In contrast to the other listed conditions, tendinitis specifically pertains to tendon inflammation. For instance, plantar fasciitis relates to inflammation of the tissue on the bottom of the foot, often due to excessive strain but not directly involving tendons in the same manner. A stress fracture is an injury involving a small crack in a bone due to repetitive stress, not tendon inflammation. IT Band Syndrome primarily affects the iliotibial band, which runs along the outside of the thigh, and does not encompass the inflammation of a tendon itself. Therefore, tendinitis is the most accurate choice as it directly addresses the inflammation of a tendon triggered by repetitive activity.