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

VBG mainly consists of the following three types: muscle pedicle grafting, vascularized fibular grafting, and vascularized iliac grafting. [62] [63] [64] [65] In addition to providing structural support, VBG also attempts to reconstruct the blood supply to the necrotic lesions. In 2006, a study [66] of vascularized iliac bone grafting reported a 66.7% (8/12) success (no progression) rate with a follow-up duration of more than 3 years for the Steinberg Stage III hips but only 37.5% for Steinberg Stage IV hips. A midterm study using free vascularized fibular grafting observed that symptoms in 91.7% (11/12) of Steinberg Stage II cases and 85.7% (24/28) of Steinberg Stage III cases improved after the operation; however, only 45% (9/20) of Steinberg Stage IV cases improved, and because the duration of follow-up (24-40 months) was not long enough, only one case that progressed to THA was observed. [67] Zeng et al. [68] used a vascularized greater trochanter bone graft combined with a free iliac flap and impaction bone grafting to treat ONFH, with a 100% good-to-excellent rate for ARCO IIIa Stage lesions. These results are in accordance with a series of other reports. [64, 66, [69] [70] [71] [72] [73] From the abovementioned studies, we noticed a satisfactory prognosis of ONFH in the pericollapse stage after joint-preserving techniques and sharply increased failure rates once evident femoral head collapse occurred [ Table 2 ]. Therefore, the pericollapse stage should end with a head collapse more than 2 mm instead of 4 mm. The pericollapse stage may be the last good opportunity for the use of joint-preserving techniques. Of note, treatment regimens for ONFH should be individualized with consideration of the age and personal needs of patients in addition to staging and classification. For the CJFH L2 and L3 types, the pericollapse stage lesions in patients aged >50 years with severe pain and joint disturbance as well as a high functional requirement, THA may be a good choice.