As the operative reconstruction of the hip joint has been developed, its use has broadened to include so many clinical conditions that it is manifestly impossible to cover all of the subjects in a paper of this type. Consequently, only the following conditions, which seem to be the most interesting and which perhaps have the broadest field of application, will be discussed:
Congenital dislocation of the hip which cannot be reduced or cannot be held within the acetabulum after reduction.
Paralytic dislocations in connection with poliomyelitis which completely dislocate or partially subluxate, giving an unstable hip.
Ununited fractures of the neck of the femur after the possibility of bony union has passed.
Much interesting work is being done in connection with other conditions, such as the painful hips in hypertrophic arthritis, unreduced traumatic dislocations and the pathologic dislocations associated with destructive lesions of the hip joint.
Arthroplasties of the hip,