High-Degree Valgus Osteotomy for Severe Femoral Head Osteonecrosis After Femoral Neck Fracture with Nonunion: A Case Report.

CASE:A 15-year-old adolescent boy had severe groin pain because of extensive osteonecrosis of the femoral head with collapse, joint space narrowing, and nonunion after a failed internal fixation for femoral neck fracture. We performed a 60° valgus osteotomy that moved the posteromedial small viable portion of the femoral head to the weight-bearing acetabular area. The femoral neck nonunion and the necrosis healed completely, and the spherical contour of the femoral head was regained after postoperative hip joint remodeling. CONCLUSIONS:Good remodeling and congruency were achieved by performing high-degree valgus osteotomy to obtain sufficient viable area below the acetabular roof.