For what did Hippocrates use the device depicted in the picture?

The Hippocratic bench or scamnum was a device invented by Hippocrates (c. 460 BC–380 BC), which used tension to aid in setting bones. It is a forerunner of the traction devices used in modern orthopedics, as well as of the rack, an instrument of torture.

The patient would lie on a bench, at an adjustable angle, and ropes would be tied around their arms, waist, legs or feet, depending on the treatment needed. Winches would then be used to pull the ropes apart, correcting curvature in the spine or separating an overlapping fracture.

Hippocrates of Kos, also known as Hippocrates II, was a Greek physician of the Age of Pericles (Classical Greece), who is considered one of the most outstanding figures in the history of medicine. He is traditionally referred to as the "Father of Medicine" in recognition of his lasting contributions to the field, such as the use of prognosis and clinical observation, the systematic categorization of diseases, or the formulation of humoural theory. The Hippocratic school of medicine revolutionized ancient Greek medicine, establishing it as a discipline distinct from other fields with which it had traditionally been associated (theurgy and philosophy), thus establishing medicine as a profession.