Fig. 4From: Simultaneous femoral head reduction osteotomy (FHRO) combined with periacetabular osteotomy (PAO) for the treatment of severe femoral head asphericity in Perthes diseaseImprovement of radiological indexes by the combined FHRO + PAO procedures a, b before surgery and c, d at the latest follow-up (Tonnis angle: 19° to 9°; Extrusion index: 50% to 10%; Sphericity index: 84% to 96%; and Shenton’s line: disrupted to intact)Back to article page