Plan of action:

Radiographs:

Survey to rule out other joint changes, skeletal abnormalities
Penn Hip to evaluate hip joints

Looking for signs of developmental problems or degenerative changes:

Joint laxity
Shallow acetabular cavities
Subluxation
Swelling, fraying, or rupture of the round ligament of the femoral head
Erosion of the articular cartilage w/ erburnation of subchondral bone
Modeling of the acetabular rim
Flattening of the femoral head
Perarticular osteophyte production and enthesophyte formation

CBC:  to rule out infectious causes