Dega osteotomy (see text). A, Osteotomy line is marked on lateral cortex of ilium; guidewire is inserted to exit just above horizontal limb of triradiate cartilage. B, Osteotome penetrates inner cortex. C, View from inner side of pelvis shows intact posteromedial cortical hinge; length of intact inner cortex depends on amount of anterior and lateral coverage desired. D, Osteotomy is levered open with osteotome or small lamina spreader. E, Larger graft is inserted anteriorly; posterior graft should be smaller to avoid loosening anterior graft. (Redrawn from Grudziak JS, Ward WT: Dega osteotomy for the treatment of congenital dysplasia of the hip, J Bone Joint Surg 83A:845, 2001.) SEE TECHNIQUE 30.11.