Which condition is primarily treated by an orthopedist?

An orthopedist specializes in diagnosing, treating, and managing conditions related to the musculoskeletal system, which includes bones, joints, ligaments, tendons, and muscles. Bone fractures specifically fall under the realm of orthopedics, as this medical specialty focuses extensively on injuries and diseases associated with bones and joints.

While other options mention various medical fields, such as cardiovascular diseases (which are treated by cardiologists), skin disorders (addressed by dermatologists), and neurological conditions (managed by neurologists), these do not pertain to the primary focus of orthopedics. Therefore, bone fractures are directly related to the expertise of an orthopedist, making this the correct answer.