Joints are the connections between two bones, and they are covered in glistening, shiny, and smooth articular hyaline cartilage. In this pristine condition, joints do not hurt, and in fact articular cartilage itself has no blood vessels or nerve endings.
However, damage to the cartilage can occur through two main mechanisms; progressive wear and tear and injury (osteoarthritis), or through systemic or auto-immune conditions (eg rheumatoid arthritis). This then leads to pain in the structures that surround the joint, such as the synovium, joint capsule and subchondral bone plate.
Arthritis is a leading cause of disability worldwide, and determining the type of arthritis you have, via medical imaging or blood tests, guides you on the prognosis and treatment options.
Bone pain, in the absence of injury (ie a fracture or break in the bone) may be due to mechanical stress (for example shin splints) or other systemic health conditions. Bone pain in the absence of trauma, particularly in children, should never be ignored as it may be a symptom of bone cancer in rare instances.