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裴 璇, 黄 进, 钱 胜, 周 唯, 柯 烯, 汪 国, 雷 建, 刘 曦. [Finite element analysis of five internal fixation modes in treatment of Day type Ⅱcrescent fracture dislocation of pelvis]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2023; 37:1205-1213. [PMID: 37848314 PMCID: PMC10581872 DOI: 10.7507/1002-1892.202306043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 08/30/2023] [Accepted: 09/06/2023] [Indexed: 10/19/2023]
Abstract
Objective To compare the biomechanical differences among the five internal fixation modes in treatment of Day type Ⅱ crescent fracture dislocation of pelvis (CFDP), and find an internal fixation mode which was the most consistent with mechanical principles. Methods Based on the pelvic CT data of a healthy adult male volunteer, a Day type Ⅱ CFDP finite element model was established by using Mimics 17.0, ANSYS 12.0-ICEM, Abaqus 2020, and SolidWorks 2012 softwares. After verifying the validity of the finite element model by comparing the anatomical parameters with the three-dimensional reconstruction model and the mechanical validity verification, the fracture and dislocated joint of models were fixed with S 1 sacroiliac screw combined with 1 LC-Ⅱ screw (S 1+LC-Ⅱ group), S 1 sacroiliac screw combined with 2 LC-Ⅱ screws (S 1+2LC-Ⅱ group), S 1 sacroiliac screw combined with 2 posterior iliac screws (S 1+2PIS group), S 1 and S 2 sacroiliac screws combined with 1 LC-Ⅱ screw (S 1+S 2+LC-Ⅱ group), S 2-alar-iliac (S 2AI) screw combined with 1 LC-Ⅱ screw (S 2AI+LC-Ⅱ group), respectively. After each internal fixation model was loaded with a force of 600 N in the standing position, the maximum displacement of the crescent fracture fragments, the maximum stress of the internal fixation (the maximum stress of the screw at the ilium fracture and the maximum stress of the screw at the sacroiliac joint), sacroiliac joint displacement, and bone stress distribution around internal fixation were observed in 5 groups. Results The finite element model in this study has been verified to be effective. After loading 600 N stress, there was a certain displacement of the crescent fracture of pelvis in each internal fixation model, among which the S 1+LC-Ⅱ group was the largest, the S 1+2LC-Ⅱ group and the S 1+2PIS group were the smallest. The maximum stress of the internal fixation mainly concentrated at the sacroiliac joint and the fracture line of crescent fracture. The maximum stress of the screw at the sacroiliac joint was the largest in the S 1+LC-Ⅱ group and the smallest in the S 2AI+LC-Ⅱ group. The maximum stress of the screw at the ilium fracture was the largest in the S 1+2PIS group and the smallest in the S 1+2LC-Ⅱ group. The displacement of the sacroiliac joint was the largest in the S 1+LC-Ⅱ group and the smallest in the S 1+S 2+LC-Ⅱ group. In each internal fixation model, the maximum stress around the sacroiliac screws concentrated on the contact surface between the screw and the cortical bone, the maximum stress around the screws at the iliac bone concentrated on the cancellous bone of the fracture line, and the maximum stress around the S 2AI screw concentrated on the cancellous bone on the iliac side. The maximum bone stress around the screws at the sacroiliac joint was the largest in the S 1+LC-Ⅱ group and the smallest in the S 2AI+LC-Ⅱ group. The maximum bone stress around the screws at the ilium was the largest in the S 1+2PIS group and the smallest in the S 1+LC-Ⅱ group. Conclusion For the treatment of Day type Ⅱ CFDP, it is recommended to choose S 1 sacroiliac screw combined with 1 LC-Ⅱ screw for internal fixation, which can achieve a firm fixation effect without increasing the number of screws.
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Affiliation(s)
- 璇 裴
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
- 武汉科技大学医学院(武汉 430081)School of Medicine, Wuhan University of Science and Technology, Wuhan Hubei, 430081, P. R. China
| | - 进成 黄
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
| | - 胜龙 钱
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
| | - 唯 周
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
- 武汉科技大学医学院(武汉 430081)School of Medicine, Wuhan University of Science and Technology, Wuhan Hubei, 430081, P. R. China
| | - 烯 柯
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
| | - 国栋 汪
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
| | - 建银 雷
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
| | - 曦明 刘
- 中国人民解放军中部战区总医院骨科(武汉 430070)Department of Orthopedics, General Hospital of Central Theater Command of Chinese PLA, Wuhan Hubei, 430070, P. R. China
- 武汉科技大学医学院(武汉 430081)School of Medicine, Wuhan University of Science and Technology, Wuhan Hubei, 430081, P. R. China
- 三峡大学附属第二人民医院骨外二科(湖北宜昌 443000)Department of OrthopedicsⅡ, Affiliated Second People’s Hospital, China Three Gorges University, Yichang Hubei, 443000, P. R. China
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Muacevic A, Adler JR, Kekatpure A. Crescent Fracture of the Pelvis: A Case Report. Cureus 2022; 14:e32944. [PMID: 36712733 PMCID: PMC9874259 DOI: 10.7759/cureus.32944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 12/25/2022] [Indexed: 12/27/2022] Open
Abstract
Crescent fractures are a rare type of pelvic injury. They result from a lateral compression force and are rotationally unstable. The following is a case of a young male who suffered a crescent fracture on the right side of the pelvis and was treated for the same. These fractures, being rare and complex, need to be managed in accordance with other injuries sustained by the patient and also need fixation for a better functional outcome.
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Wu C, Zeng B, Deng J, Qin B, Shen D, Wang X, Hu H, Huang L, Liu X, Qiu G. Finite Element Analysis and Transiliac-Transsacral Screw Fixation for Posterior Pelvic Ring with Sacrum Dysplasia. Orthop Surg 2022; 15:337-346. [PMID: 36424734 PMCID: PMC9837241 DOI: 10.1111/os.13585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 09/23/2022] [Accepted: 10/17/2022] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE Posterior pelvic ring sacroiliac screws are preferred by clinicians for their good biomechanical performance. However, there are few studies on mechanical analysis and intraoperative screw insertion of the dysplastic sacrum and sacroiliac screw. This study investigated the biomechanical performance of oblique sacroiliac screws (OSS) in S1 combined with transiliac-transsacral screws (TTSs) in S2 for pelvic fracture or sacroiliac dislocation with dysplastic sacrum and evaluated the safety of screw placement assisted by the navigation template. METHODS Six models were established, including one OSS fixation in the S2 segment, one transverse sacroiliac screw (TSS) fixation in the S2 segment, one TTS fixation in the S2 segment, one OSS fixation in the S1 and S2 segments, one OSS fixation in the S1 segment and one TSS fixation in the S2 segment, one OSS fixation in the S1 segment and one TTS fixation in the S2 segment. Then, finite element analysis (FEA) was performed. Twelve dysplastic sacrum patients with pelvis fracture or sacroiliac dislocation underwent OSS insertion in the S1 combined with TTS insertion in the S2 under the assistance of the patient-specific locked navigation template. Grading and Matta scores were evaluated after surgery. RESULTS In the one-screw fixation group, the vertical displacements of the sacrum surface of S2 OSS, S2 TSS and S2 TTS were 1.23, 1.42, and 1.22 mm, respectively, and the maximum stress of screw were 139.45 MPa, 144.81 MPa, 126.14 MPa, respectively. In the two-screw fixation group, the vertical displacements of the sacrum surface of the S1 OSS + S2 OSS, S1 OSS + S2 TSS and S1 OSS + S2 TTS were 0.91, 1.06, and 0.75 mm, respectively, and the maximum stress of screw were 149.26 MPa, 167.13 Pa, 136.76 MPa, respectively. Clinically, a total of 12 TTS and OSS were inserted under the assistance of navigation templates, with a surgical time of 55 ± 7.69 min, bleeding of 57.5 ± 18.15 ml and radiation times of 14.5 ± 4.95. One of the TTS and one of the OSS were grade 1, and the other screws were grade 0. The Matta scores of nine patients were excellent, and three patents were good. CONCLUSION OSS in the S1 combined with TTS in the S2 had the best mechanical stability in six models, and it is safe for screw insertion assisted by the patient-specific locked navigation template.
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Affiliation(s)
- Chao Wu
- Department of OrthopaedicsZigong Fourth People's HospitalZigongChina,Institute of Digital MedicineZigong Academy of Big Data for Medical Science and Artificial IntelligenceZigongChina
| | - Baifang Zeng
- Department of OrthopaedicsZigong Fourth People's HospitalZigongChina,Department of OrthopaedicsAffiliated Hospital of Southwest Medical UniversityLuzhouChina
| | - Jiayan Deng
- Institute of Digital MedicineZigong Academy of Big Data for Medical Science and Artificial IntelligenceZigongChina
| | - Binwei Qin
- Department of OrthopaedicsZigong Fourth People's HospitalZigongChina,Department of OrthopaedicsAffiliated Hospital of Southwest Medical UniversityLuzhouChina
| | - Danwei Shen
- Institute of Digital MedicineZigong Academy of Big Data for Medical Science and Artificial IntelligenceZigongChina
| | - Xiangyu Wang
- Department of OrthopaedicsZigong Fourth People's HospitalZigongChina
| | - Haigang Hu
- Department of OrthopaedicsZigong Fourth People's HospitalZigongChina
| | - Li Huang
- Operation CenterZigong Fourth People's HospitalZigongChina
| | - Xin Liu
- Health Management CenterZigong Fourth People's HospitalZigongChina
| | - Guigang Qiu
- Department of OrthopaedicsZigong Fourth People's HospitalZigongChina
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Huang G, Chen K, Wang Y, Guo X. Finite element analysis of the Union Plate in treating elderly acetabular fracture patients. J Orthop Surg Res 2022; 17:56. [PMID: 35093112 PMCID: PMC8800209 DOI: 10.1186/s13018-022-02951-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 01/21/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Elderly acetabular fractures are one of the more difficult types of fractures to resolve. For patients at this age, the more common type of fracture is comminuted. How to better fix this type of fracture has always been an issue of concern. This study was performed to observe the mechanical properties of different internal fixation methods used in treating elderly acetabular fracture patients. METHODS A model of a comminuted acetabular fracture in osteoporosis was established, consisting of an anterior column-posterior hemitransverse fracture with disruption of the quadrilateral surface. Fixation of the acetabular fracture model using a reconstruction plate and Union Plates was simulated. For the different internal fixation methods, static and transient modal analyses were performed under different loads, with an action time of 0.21 s and an analysis time of 0.7 s. The stress of the model was observed in the static analysis, and the displacement of the nodes and the entire model in the U1 direction was observed in the transient modal analysis. RESULTS In the static analysis, the stress of the osteoporosis model, the suprapectineal pelvic reconstruction plate model, the infrapectineal quadrilateral surface buttress plate model, and the suprapectineal quadrilateral surface buttress plate model were 42.62 MPa, 37.49 MPa, 44.39 MPa, and 46.15 MPa, respectively. The stress was mainly distributed near the suprapubic branch. The corresponding displacement in the U1 direction was 0.1500 mm, 0.1020 mm, 0.0836 mm, and 0.0990 mm, respectively. In the transient modal analysis, there was a significant difference in displacement between the different models (P < 0.05). When different loads were applied with the same fixation method, there was no significant difference in model displacement (P > 0.05). CONCLUSION Static and transient modal analyses show that the infrapectineal quadrilateral surface buttress plate or the suprapectineal quadrilateral surface buttress plate has an advantage in maintaining the stability of fracture fragments when fixing comminuted acetabular fractures in elderly individuals. The infrapectineal quadrilateral surface buttress plate also presents better biomechanical results.
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Affiliation(s)
- Guixiong Huang
- Department of Orthopaedics, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People's Republic of China
| | - Kaifang Chen
- Department of Orthopaedics, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People's Republic of China
| | - Yulong Wang
- Department of Orthopaedics, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People's Republic of China
| | - Xiaodong Guo
- Department of Orthopaedics, Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People's Republic of China.
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Han W, Zhang T, Su YG, Zhao CP, Zhou L, Wu XB, Wang JQ. Percutaneous Robot-Assisted versus Freehand S 2 Iliosacral Screw Fixation in Unstable Posterior Pelvic Ring Fracture. Orthop Surg 2021; 14:221-228. [PMID: 34904387 PMCID: PMC8867425 DOI: 10.1111/os.13056] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 04/06/2021] [Accepted: 04/29/2021] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVES To assess the efficiency, safety, and accuracy of S2 (IS) screw fixation using a robot-assisted method compared with a freehand method. METHODS This is a retrospective clinical study. We analyzed the patients treated with S2 IS screw fixation for unstable pelvic fractures from January 2016 to January 2019 in our institution. Sixty-three patients (17 men and 46 women) aged between 21 and 55 years (with an average age of 39.22 ± 9.28) were included in this study. According to the Tile classification, there were 26 (41.3%) type B fractures and 37 (58.7%) type C fractures. All patients were divided into robot-assisted (RA) group (38 patients) or the traditional freehand (FH) group (25 patients). In RA group, the S2 IS screws were implanted with a robot-assisted technique. And S2 IS screws were implanted with a traditional freehand technique in FH group. The screw-related complications were recorded during and after the surgery. The position of all screws and fracture reduction was assessed by postoperative CT scans according to the Gras classification. The number of guide wire attempts and the radiation exposure for S2 screw implantation during operation were also recorded. Finally, the Matta standard was used to evaluate the fracture reduction of the IS joint. RESULTS A total of 89 IS screws were implanted into S2 iliosacral joint. Fifty-four screws were placed by RA (38 patients) and 35 screws were by FH (25 patients). There was no difference between the two groups with respect to demographic data. There was no screw-related complications or revision surgery in any group. In terms of screw placement, the excellent and good rate was 100% in the RA group, better than that in the FH group where it was only 85.7% (P < 0.001). The fluoroscopy time was 8.06 ± 3.54 s in RA group, which was much less than that in the FH group (27.37 ± 8.82 s, P < 0.001). The guide wire attempts in the RA group (0.685 ± 0.820) were much less than those in the FH group (5.77 ± 3.34) (P < 0.001). Both the fluoroscopy time per screw and the number of guide wire attempts in the RA group were much less than those in the FH group (P < 0.001). The overall postoperative excellent and good rate of Matta standard in RA and FH groups were 86.8% (34/4) and 90.0% (23/25), respectively (P = 0.750), and there was no statistical difference. CONCLUSION The robot-assisted surgery is an accurate and minimally invasive technique. S2 IS screw implantation assisted by TiRobot to treat the posterior pelvic ring fractures, have a high success rate than the freehand technique. Percutaneous RA S2 IS screw fixation for unstable posterior pelvic ring injuries is safe and clinically feasible and has great clinical application value.
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Affiliation(s)
- Wei Han
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
| | - Teng Zhang
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
| | - Yong-Gang Su
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
| | - Chun-Peng Zhao
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
| | - Li Zhou
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
| | - Xin-Bao Wu
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
| | - Jun-Qiang Wang
- Department of Traumatology, Beijing Jishuitan Hospital, Beijing, China
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Bansal H, Gupta A, Mittal S, Trikha V. Concerns regarding biomechanical stability of different fixations models in crescent fracture dislocation. J Orthop Translat 2021; 26:181-182. [PMID: 33437637 PMCID: PMC7773971 DOI: 10.1016/j.jot.2020.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/14/2020] [Accepted: 08/25/2020] [Indexed: 11/25/2022] Open
Affiliation(s)
- Hemant Bansal
- Department of Orthopedics, JPNATC, AIIMS, New Delhi, India
| | - Anupam Gupta
- Department of Orthopedics, JPNATC, AIIMS, New Delhi, India
| | - Samarth Mittal
- Department of Orthopedics, JPNATC, AIIMS, New Delhi, India
| | - Vivek Trikha
- Department of Orthopedics, JPNATC, AIIMS, New Delhi, India
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Xiang G, Dong X, Jiang X, Cai L, Wang J, Guo X, Xiao J, Feng Y. Comparison of percutaneous cross screw fixation versus open reduction and internal fixation for pelvic Day type II crescent fracture-dislocation: case-control study. J Orthop Surg Res 2021; 16:36. [PMID: 33422105 PMCID: PMC7797106 DOI: 10.1186/s13018-020-02197-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 12/30/2020] [Indexed: 11/11/2022] Open
Abstract
Objective To investigate the clinical outcomes of percutaneous cross screws internal fixation for pelvic Day type II crescent fracture-dislocation. Methods We reviewed 66 consecutive patients undergoing surgical treatment for Day type II crescent fracture-dislocation from June 2005 to December 2017. Percutaneous cross screws internal fixation was performed in 40 patients, and open reduction and internal fixation was performed in 26 patients. The patient characteristics, surgical complications, radiographic and clinical outcomes and were compared. Results There was no statistically difference on the mean time from injury to surgery between the two groups. The time of operation, the amount of blood loss, the length of incision, and the hospital stay were significantly shorter in the percutaneous cross screws internal fixation group. No significant difference on Matta scores and Majeed scores between the two groups. The open reduction and internal fixation group resulted in a higher rate of intraoperative hemorrhage, nerve injury, discomfort, and pain. Conclusion Percutaneous cross screws internal fixation for Day II type pelvic crescent fracture-dislocation was safe and effective. Minimally invasive fixation had the advantages of short operation and hospitalization time, less intraoperative bleeding, and surgical trauma.
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Affiliation(s)
- Guangheng Xiang
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.,School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Xiaoyu Dong
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Xingan Jiang
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Leyi Cai
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Jianshun Wang
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Xiaoshan Guo
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Jian Xiao
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China. .,School of Pharmaceutical Sciences, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.
| | - Yongzeng Feng
- Department of Orthopaedic, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China.
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Pang Y, Zhang K, Liu L, Feng D, Liu C, Wang J, Du Y, Guo Z. [Biomechanical study of cystic lesions of the mandible based on a three-dimensional finite element model]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2020; 40:911-915. [PMID: 32895206 DOI: 10.12122/j.issn.1673-4254.2020.06.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To analyze the biomechanics of cystic lesions in the mandibular body in a three-dimensional (3D) finite element model. METHODS A 3D finite element model of cystic lesion of the mandibular body was constructed based on the CT images of the mandible of a healthy adult female volunteer with normal occlusion. The size of the cyst and the residual bone wall were analyzed when the lesion area approached the stress peak under certain constraints and loading conditions. RESULTS When the size of the cyst reached 37.63 mm×11.32 mm×21.45 mm, the maximal von Mises stress in the lesion area reached 77.295 MPa, close to the yield strength of the mandible with a risk of pathological fracture. At this point, the remaining bone thickness of the buccal and lingual sides and the lower margin of the mandible in the lesion area was 1.52 mm, 0.76 mm and 1.04 mm, respectively. CONCLUSIONS Residual bone mass is an important factor to affect the risk of pathological fracture after curettage of cystic lesions. A thickness as low as 1 mm of the residual bone cortex in the cystic lesion area of the mandibular body can be used as the threshold for a clinical decision on one-stage windowing decompression combined with two- stage curettage.
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Affiliation(s)
- Yaqian Pang
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
| | - Kai Zhang
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
| | - Liang Liu
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
| | - Dajun Feng
- Department of Oral and Maxillofacial Surgery, Fourth Affiliated Hospital of Anhui Medical University, Hefei 230001, China
| | - Chang Liu
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
| | - Jing Wang
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
| | - Yue Du
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
| | - Zhenfei Guo
- Department of Stomatology, First Affiliated Hospital of Bengbu Medical College, Bengbu 233000, China
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Affiliation(s)
- Ming Zhang
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, China
| | - He Gong
- School of Biological Science and Medical Engineering, Beihang University, China
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