Pericollapse Stage of Osteonecrosis of the Femoral Head: A Last Chance for Joint Preservation

Zhang, Qing-Yu; Li, Zi-Rong; Gao, Fu-Qiang; Sun, Wei

The rationale of femoral osteotomy is to transpose the healthy portion of the femoral head to the weight-bearing area and therefore restore joint congruity, which is mainly suitable for ONFH patients of a young age (<40 years), low body mass index (<25 kg/m 2 ), early-stage lesions, and a large postoperative intact ratio. [15] Even in the promising long-term results of angular intertrochanteric and transtrochanteric rotational osteotomies reported in multiple studies in which ARCO Stage IIIa lesions or late-stage osteonecrosis (ON) is present, the progressive collapse of a relocated necrotic lesion was significantly associated with a larger level of preoperative collapse (2.1 ± 1.0 mm in the progressive collapse group vs. 4.4 ± 1.4 mm in the nonprogressive collapse group). [52] [53] [54] Meanwhile, osteotomy is less frequently used in China and Western countries due to the complexity of the operation and the high rate of complications (nonunion, delayed union, fixation failure, and increased difficulty in future THA, etc.). [55, 56]