Finite element analysis of treatment for Sanders type IIB intra-articular calcaneal fracture by percutaneous screws
10.3760/cma.j.cn121113-20250120-00057
- VernacularTitle:经皮螺钉固定治疗SandersⅡB型跟骨关节内骨折的三维有限元分析及临床验证
- Author:
Yixuan CHEN
1
;
Jiachen WU
1
;
Chang LIU
1
;
Tianyi WU
1
;
Shang GUO
1
;
Jiangyu CAI
1
;
Ting WANG
1
;
Mingjie TANG
1
;
Zhongmin SHI
1
;
Xin MA
1
Author Information
1. 上海交通大学附属第六人民医院骨科，上海 200233
- Publication Type:Journal Article
- Keywords:
Calcaneus;
Fracture fixation, internal;
Minimally invasive surgical procedures;
Finite element analysis;
Percutaneous screw;
Support of medial column
- From:
Chinese Journal of Orthopaedics
2025;45(19):1241-1250
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To evaluate the stability of percutaneous screw fixation for minimally invasive treatment of intra-articular calcaneal fractures using three-dimensional finite element analysis.Methods:CT scan was performed on the calcaneus of a normal adult for three-dimensional reconstruction. The DICOM data were imported into Mimics software to establish a model of a Sanders type IIB intra-articular calcaneal fracture. Based on the Essex-Lopresti classification of posterior facet morphology, the model was subdivided into two subtypes: tongue-type and depression-type. The calcaneus was divided into four fragments: sustentaculum tali, posterior tuberosity, anterior process (three points), and posterior articular surface (one surface). Two types of fixation methods, classical lateral anatomical plates and combinations of percutaneous screws, were simulated and performed. A three-dimensional finite element analysis was conducted by applying a stress combination of 420 N on the posterior subtalar articular surface, 200 N on the middle subtalar articular surface, and 300 N at the Achilles tendon insertion point. The maximum displacement and von Mises stress values of each bone fragment and implant were recorded to evaluate the biomechanical stability. For clinical validation, 34 patients with Sanders type IIB calcaneal fractures from Orthopedics Department of the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University were treated with percutaneous reduction and screw fixation using the following configurations.Results:Under simulated stress, the A4 group with medial support screws in the tongue-type fracture subgroup demonstrated minimal overall calcaneal displacement (0.22 mm) and internal fixation displacement (0.14 mm). For the depression-type, the B2 group with medial support screws showed lower maximum stress in the calcaneus and internal fixation, at 22.04 MPa and 41.14 MPa, respectively, along with the lowest overall displacement (0.14 mm). The peak stress of all groups of implants remained below the material yield strength. The A4 and B2 protocols were applied to 15 cases of tongue-type calcaneal fractures and 19 cases of collapse-type calcaneal fractures. At the final follow-up The American Orthopaedic Foot & Ankle Society ankle-hindfoot score scale was 86.1±5.82 and 87.2±5.18, respectively, while the visual analog scale for pain was 1.60±1.24 and 1.58±1.02, respectively.Conclusions:Percutaneous screw fixation provided reliable stability for Sanders type IIB calcaneal fractures. The fixation configuration incorporating a medial support screw offers superior biomechanical performance in both tongue-type and depression-type fractures, representing an optimized minimally invasive technique with strong clinical applicability.
