Nomogram to predict collapse-free survival after core decompression of nontraumatic osteonecrosis of the femoral head

En-Ze Zhao,Wei-Nan Zeng,Zun-Han Liu,Zhen-Yu Luo,Zong-Ke Zhou,Zi-Chuan Ding

doi:10.1186/s13018-021-02664-3

Abstract

BackgroundNontraumatic osteonecrosis of the femoral head (NONFH) is a devastating disease, and the risk factors associated with progression into collapse after core decompression (CD) remain poorly defined. Therefore, we aim to define risk factors associated with collapse-free survival (CFS) after CD of precollapse NONFH and to propose a nomogram for individual risk prediction.MethodsAccording to the baseline characteristics, clinical information, radiographic evaluations, and laboratory examination, a nomogram was developed using a single institutional cohort of patients who received multiple drilling for precollapse NONFH between January 2007 and December 2019 to predict CFS after CD of precollapse NONFH. Furthermore, we used C statistics, calibration plot, and Kaplan-Meier curve to test the discriminative ability and calibration of the nomogram to predict CFS.ResultsOne hundred and seventy-three patients who underwent CD for precollapse NONFH were retrospectively screened and included in the present study. Using a multiple Cox regression to identify relevant risk factors, the following risk factors were incorporated in the prediction of CFS: acute onset of symptom (HR, 2.78; 95% CI, 1.03–7.48; P = 0.043), necrotic location of Japanese Investigation Committee (JIC) C1 and C2 (HR, 3.67; 95% CI, 1.20–11.27; P = 0.023), necrotic angle in the range of 250–299°(HR, 5.08; 95% CI, 1.73–14.93; P = 0.003) and > 299° (HR, 9.96; 95% CI, 3.23–30.70; P < 0.001), and bone marrow edema (BME) before CD (HR, 2.03; 95% CI, 1.02-4.02; P = 0.042). The C statistics was 0.82 for CFS which revealed good discriminative ability and calibration of the nomogram.ConclusionsIndependent predictors of progression into collapse after CD for precollapse NONFH were identified to develop a nomogram predicting CFS. In addition, the nomogram could divide precollapse NONFH patients into prognosis groups and performed well in internal validation.

Highlights

Osteonecrosis of the femoral head (ONFH) is a devastating disease and becomes an increasing worldwide health problem [1, 2]
nontraumatic ONFH (NONFH) often leads to femoral head collapse which inevitably results in hip arthroplasty later
According to the Ficat classification for NONFH, 18 patients were identified as Ficat I stage and 155 patients were identified as Ficat IIA stage at the time of surgery

Summary

Introduction

Osteonecrosis of the femoral head (ONFH) is a devastating disease and becomes an increasing worldwide health problem [1, 2]. To prolong the time interval before progression into collapse even to avoid collapse, core decompression (CD) was proposed to preserve the affected hips by reducing intraosseous hypertension and promoting revascularization of the femoral head, which have been reported with clinical success especially in precollapse NONFH cases [5,6,7]. Despite several radiomic features associated with the collapse that have been reported in previous studies [11, 12], reliable prognostication among patients with precollapse NONFH after CD remains a challenge. Nontraumatic osteonecrosis of the femoral head (NONFH) is a devastating disease, and the risk factors associated with progression into collapse after core decompression (CD) remain poorly defined. We aim to define risk factors associated with collapse-free survival (CFS) after CD of precollapse NONFH and to propose a nomogram for individual risk prediction

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Discussion

Conclusion