Mainly it's
Musclo-skeletal problems like back and neck, shoulders, knees, elbows, ankles (so the limbs as well).
The body is a self regulating mechanism and an Osteopath can work with the Central Nervous System thereby supporting the body in its self healing process. This process means that (although not clinically trialled) patients often report improvement for
internal problems: involving the head, the gut, the lungs. Osteopathy doesn't claim to 'cure' but to work (alongside allopathic midicine) with the body to help it restore its own balance- in many cases with relief of pain and improved mobility.