Observation

Orthosis

Devices or appliances used to correct or straighten a deformity.

Orthotics

The science concerned with the making and fitting of orthopedic appliances.

Osgood-Schlatter disease

Inflammation or partial avulsion of the tibial apophysis due to traction forces.

Osteitis pubis

Stress fracture to the pubic symphysis caused by repeated overload of the adductor muscles or repetitive stress activities

Osteoarthritis

A condition caused by wear and tear that causes inflammation of the joint, causing swelling, pain, and stiffness.

Osteochondral fracture

Fracture involving the articular cartilage and underlying bone.

Osteochondritis dissecans

Localized area of avascular necrosis resulting in complete or incomplete separation of joint cartilage and subchondral bone.

Osteochondrosis

Any condition characterized by degeneration of aseptic necrosis of the articular cartilage due to limited blood supply.

Osteomyelitis

Inflammation or infection of the bone and bone marrow.

Osteopenia

Condition of reduced bone mineral density that predisposed the individual to fractures.

Osteoporosis

Overload principle

Physiologic improvements occur only when an individual physically demands more of the muscles than is normally required.

Overuse injury

Any injury caused by excessive repetitive movement of the body part.