Zhang Jin1*, Luo Chen2*, Dafeng Wang1, Yayun Ye3, Jiaxing Fu1, Zhifan Yang1, Baoqiang He4

1Department of Orthopedics, Wenzhou People’s Hospital, Wenzhou, Zhejiang Province, China
2Department of Orthopedics, Zhuji Second People’s Hospital, Zhuji, Zhejiang Province, China
3Department of Acupuncture, Wenzhou People’s Hospital, Wenzhou, Zhejiang Province, China
4Department of Acupuncture, Yangxian People’s Hospital, Hanzhong, Shaanxi Province, China

Keywords: Femoral head, fracture, internal fixation, osteonecrosis, prediction model.

Abstract

Objectives: This study aims to investigate the high-risk factors for osteonecrosis of the femoral head (ONFH) after internal fixation with multiple cannulated compression screws for adult femoral neck fractures and to construct a prediction model.

Patients and methods: Between from January 2012 and December 2020, a total of 268 patients (138 males, 130 females; mean age: 53±10 years; range, 23 to 70 years) with ONFH who had complete follow-up data were included. Closed reduction in combination with open reduction were performed. All patients received internal fixation with multiple cannulated compression screws and were assigned to ONFH and non-ONFH groups. Logistic regression model was utilized to identify independent risk factors for postoperative ONFH, followed by constructing a nomogram prediction model. The predictive ability of the model was evaluated by receiver operating characteristic curve, Hosmer-Lemeshow test, and calibration curve.

Results: Multivariate analysis revealed that older age (odds ratio [OR]: 2.307, 95% confidence interval [CI]: 1.295-4.108], Charlson Comorbidity Index (CCI) ≥2 (OR: 2.214, 95% CI: 1.035-4.739), fracture displacement (OR: 2.426, 95% CI: 1.122-5.247), unsatisfactory reduction (OR: 2.629, 95% CI: 1.275-5.423), postoperative removal of internal fixation implant (OR: 2.200, 95% CI: 1.051-4.604) were independent risk factors for postoperative ONFH (p<0.05). The nomogram prediction model constructed based on these clinical characteristics showed high predictive value (AUC=0.807) and consistency (p>0.05).

Conclusion: Age, comorbidity index, fracture type, reduction quality and postoperative removal of internal fixation implant are of utmost importance for postoperative ONFH in patients with femoral neck fractures. The established nomogram prediction model can accurately predict the occurrence of postoperative ONFH.

* The two authors contributed equally to this study

Citation: Jin Z, Chen L, Wang D, Ye Y, Fu J, Yang Z, He B. A prediction model for osteonecrosis of femoral head after internal fixation with multiple cannulated compression screws for adult femoral neck fractures. Jt Dis Relat Surg 2024;35(1):20-26. doi: 10.52312/jdrs.2024.975.

Ethics Committee Approval

The study protocol was approved by the Yangxian People's Hospital Ethics Committee (date: 04.01.2012, no: KY-2023-322). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Author Contributions

Designed this study and prepared this manuscript: Z.J., L.C., D.W.; Collected and analyzed clinical data: Y.Y., J.F.; Writing: Z.Y., B.H. All authors approved the final version of this manuscript.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

This study was financially supported by the Zhejiang Province Traditional Chinese Medicine Project (No. 2020ZB308).

Data Sharing Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.