What is the field of medicine that focuses on manipulation of bones to treat diseases?

The field of medicine that focuses on the manipulation of bones to treat diseases is osteopathy. Osteopathic medicine emphasizes a holistic approach to healthcare, incorporating the manipulation of the musculoskeletal system in the diagnosis and treatment of various conditions. Osteopaths are trained to use their hands to diagnose and treat problems related to joints, muscles, and bones, which aligns with the question's focus on manipulating bones.

In this context, the other fields mentioned have different focuses: physiatry primarily deals with rehabilitation and physical medicine, chiropractic focuses specifically on spinal adjustments and associated nervous system issues, while orthopedics is concerned with the surgical and non-surgical treatment of musculoskeletal injuries and diseases but does not emphasize manual manipulation of bones in the same way osteopathy does.