Final answer:
Costochondritis is the inflammation of the cartilage connecting a rib to the sternum, involving the costal cartilage, and it differs from Arthritis, Tenosynovitis, Pharyngitis, and Osteomyelitis.
Step-by-step explanation:
The inflammation of the cartilage which connects a rib to the sternum is known as Costochondritis. This condition involves the costal cartilage, which is a hyaline cartilage structure attached to the anterior end of each rib, enabling direct or indirect attachment of most ribs to the sternum.
The term Costochondritis specifically refers to the inflammation of this cartilage, often causing chest pain which can be confused with heart-related conditions. It is different from other conditions such as Arthritis, which generally refers to inflammation of the joints; Tenosynovitis, inflammation of the sheath around a tendon; Pharyngitis, inflammation of the pharynx; and Osteomyelitis, which is an infection in the bone.