Micro-Computed Tomography Analysis of Femoral Head Necrosis After Long-Term Internal Fixation for Femoral Neck Fracture

Yang Liu; Haoran Liang; Xin Zhou; Wenjie Song; Huifeng Shao; Yong He; Yanfei Yang; Li Guo; Pengcui Li; Xiaochun Wei; Wangping Duan

doi:10.1111/os.13318

Micro-Computed Tomography Analysis of Femoral Head Necrosis After Long-Term Internal Fixation for Femoral Neck Fracture

Orthop Surg. 2022 Jun;14(6):1186-1192. doi: 10.1111/os.13318. Epub 2022 May 19.

Authors

Yang Liu^{1

2}, Haoran Liang^{1

2}, Xin Zhou^{1

2}, Wenjie Song^{1

2}, Huifeng Shao^{3

4

5}, Yong He^{4

5}, Yanfei Yang^{1

2}, Li Guo^{1

2}, Pengcui Li^{1

2}, Xiaochun Wei^{1

2}, Wangping Duan^{1

2}

Affiliations

¹ Department of Orthopaedics, Second Hospital of Shanxi Medical University, Taiyuan, China.
² Shanxi Key Laboratory of Bone and Soft Tissue Injury Repair, Taiyuan, China.
³ School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou, China.
⁴ State Key Laboratory of Fluid Power and Mechatronic Systems, School of Mechanical Engineering, Zhejiang University, Hangzhou, China.
⁵ Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province, School of Mechanical Engineering, Zhejiang University, Hangzhou, China.

Abstract

Objective: To analyze necrotic femoral head after long-term internal fixation for femoral neck fractures using micro-computed tomography (CT) for bone histomorphometry.

Methods: The experimental group included six patients (two men and four women; mean age 62.00 ± 9.36 years) who underwent hip arthroplasty at 47.67 ± 14.22 months after internal fixation. Surgery was performed because of femoral head necrosis after femoral neck fracture between October 2018 and October 2020. The control group included three patients (two men and one woman; mean age 69.33 ± 4.62 years) who underwent hip arthroplasty for femoral neck fracture. In the experimental group, micro-CT quantitative analysis of the whole femur, sclerotic region around screws, screw paths, sclerotic region and screw paths, and relatively normal region was performed. The bone volume fraction (BV/TV), number of bone trabeculae (Tb.N), connection density (Conn.D), thickness of bone trabeculae (Tb.Th), separation of bone trabeculae (Tb.SP), structural model index (SMI), and bone mineral density (BMD) of each part were quantitatively analyzed.

Results: The BV/TV (0.3180 ± 0.0617), Conn.D (6.9261 ± 2.4715/mm³ ), Tb.Th (0.3262 ± 0.0136 μm), and BMD (298.9241 ± 54.2029 g/cm³ ) of the sclerotic region around the screws were significantly higher in the experimental group than the BV/TV (0.1248 ± 0.0390), Conn.D (2.5708 ± 0.5187/mm³ ), Tb.Th (0.1713 ± 0.0333 μm), and BMD (66.5181 ± 43.0380 g/cm³ ) in the control group (P < 0.05). The BV/TV (0.2222 ± 0.0684), Tb.Th (0.2775 ± 0.0326 μm), and BMD (195.0153 ± 71.8509 g/cm³ ) in the collapsed region were significantly higher in the experimental group than in the control group (P < 0.05). In the experimental group, the volume ratio of the sclerotic region around screws and screw paths to the entire femoral head was 0.4964 ± 0.0950.

Conclusion: After internal fixation for femoral neck fracture, a large number of sclerotic plate-like trabeculae were observed around the long-term retained implant. The screw paths and surrounding sclerotic comprise approximately 50% of the femoral head volume.

Keywords: Femoral neck fracture; Femur head; Microcomputed tomography; Necrosis; Three-dimensional imaging.

MeSH terms

Aged
Bone Density
Female
Femoral Neck Fractures* / diagnostic imaging
Femoral Neck Fractures* / surgery
Femur Head
Femur Head Necrosis* / diagnostic imaging
Femur Head Necrosis* / surgery
Fracture Fixation, Internal
Humans
Male
Middle Aged
X-Ray Microtomography

Abstract

MeSH terms

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