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Huang J, Yan K, Wu C, Tan QC, Bai H, Wang J, Liao B, Wu ZX. Prognosis and conditional nomogram of cervical spine fracture in patients with severe spinal cord injury: a multicenter retrospective study. Int J Surg 2023; 109:1271-1280. [PMID: 36999783 PMCID: PMC10389578 DOI: 10.1097/js9.0000000000000365] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 03/12/2023] [Indexed: 04/01/2023]
Abstract
INTRODUCTION Cervical spine fractures with severe spinal cord injury (SCI) are common following cervical spine trauma and are associated with a high mortality rate. Understanding the mortality patterns of patients with cervical spine fractures and severe SCI can offer valuable evidence to surgeons and family members who are required to make critical healthcare decisions. The authors aimed to evaluate the instantaneous death risk and conditional survival (CS) of such patients and developed conditional nomograms to account for different periods of survivors and predict the survival rates. METHODS Their instantaneous death risks were calculated using the hazard function, and the Kaplan-Meier method was used to evaluate the survival rates. Cox regression was used to choose the variables for the construction of the nomograms. The area under the receiver operating characteristic curve and calibration plots were used to validate the performance of the nomograms. RESULTS The authors finally included 450 patients with cervical spine fractures and severe SCI using propensity score matching. The instantaneous death risk was the highest during the first 12 months after injury. Surgical treatment can help decrease the instantaneous death risk quickly, especially in early-term surgery. The 5-year CS increased constantly from 73.3% at baseline to 88.0% after 2 years of survival. Conditional nomograms were constructed at baseline and in those who survived for 6 and 12 months. The area under the receiver operating characteristic curve and calibration curves indicated that the nomograms had a good performance. CONCLUSION Their results improve our understanding of the instantaneous death risk of patients in different periods following injury. CS demonstrated the exact survival rate among medium-term and long-term survivors. Conditional nomograms are suitable for different survival periods in predicting the probability of survival. Conditional nomograms help in understanding the prognosis and improve the shared decision-making approaches.
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Affiliation(s)
| | - Kang Yan
- Department of Orthopaedics, Tangdu Hospital, The Air Force Medical University, Xi’an, Shaanxi
| | - Chenyu Wu
- Department of Orthopaedics, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, People’s Republic of China
| | | | - Hao Bai
- Department of Orthopaedics, Xijing Hospital
| | - Jing Wang
- Department of Orthopaedics, Xijing Hospital
| | - Bo Liao
- Department of Orthopaedics, Tangdu Hospital, The Air Force Medical University, Xi’an, Shaanxi
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Tan QC, Jiang XS, Chen L, Huang JF, Zhou QX, Wang J, Zhao Y, Zhang B, Sun YN, Wei M, Zhao X, Yang Z, Lei W, Tang YF, Wu ZX. Bioactive graphene oxide-functionalized self-expandable hydrophilic and osteogenic nanocomposite for orthopaedic applications. Mater Today Bio 2022; 18:100500. [DOI: 10.1016/j.mtbio.2022.100500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/30/2022] [Accepted: 11/18/2022] [Indexed: 11/26/2022] Open
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Tan QC, Huang JF, Bai H, Liu ZX, Huang XY, Zhao X, Yang Z, Du CF, Lei W, Wu ZX. Effects of Revision Rod Position on Spinal Construct Stability in Lumbar Revision Surgery: A Finite Element Study. Front Bioeng Biotechnol 2022; 9:799727. [PMID: 35071208 PMCID: PMC8766337 DOI: 10.3389/fbioe.2021.799727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/03/2021] [Indexed: 11/28/2022] Open
Abstract
Revision surgery (RS) is a necessary surgical intervention in clinical practice to treat spinal instrumentation–related symptomatic complications. Three constructs with different configurations have been applied in RS. One distinguishing characteristic of these configurations is that the revision rods connecting previous segments and revision segments are placed alongside, outside, or inside the previous rods at the level of facetectomy. Whether the position of the revision rod could generate mechanical disparities in revision constructs is unknown. The objective of this study was to assess the influence of the revision rod position on the construct after RS. A validated spinal finite element (FE) model was developed to simulate RS after previous instrumented fusion using a modified dual-rod construct (DRCm), satellite-rod construct (SRC), and cortical bone trajectory construct (CBTC). Thereafter, maximum von Mises stress (VMS) on the annulus fibrosus and cages and the ligament force of the interspinous ligament, supraspinous ligament, and ligamentum flavum under a pure moment load and a follower load in six directions were applied to assess the influence of the revision rod position on the revision construct. An approximately identical overall reducing tendency of VMS was observed among the three constructs. The changing tendency of the maximum VMS on the cages placed at L4-L5 was nearly equal among the three constructs. However, the changing tendency of the maximum VMS on the cage placed at L2-L3 was notable, especially in the CBTC under right bending and left axial rotation. The overall changing tendency of the ligament force in the DRCm, SRC, and CBTC was also approximately equal, while the ligament force of the CBTC was found to be significantly greater than that of the DRCm and SRC at L1-L2. The results indicated that the stiffness associated with the CBTC might be lower than that associated with the DRCm and SRC in RS. The results of the present study indicated that the DRCm, SRC, and CBTC could provide sufficient stabilization in RS. The CBTC was a less rigid construct. Rather than the revision rod position, the method of constructing spinal instrumentation played a role in influencing the biomechanics of revision.
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Affiliation(s)
- Quan-Chang Tan
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China.,Department of Orthopaedics, Air Force Hospital of Eastern Theater Command, Nanjing, China
| | - Jin-Feng Huang
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Hao Bai
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Zi-Xuan Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, China
| | - Xin-Yi Huang
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Xiong Zhao
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Zhao Yang
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Cheng-Fei Du
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.,National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, China
| | - Wei Lei
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
| | - Zi-Xiang Wu
- Department of Orthopaedics, Xijing Hospital, The Air Force Medical University, Xi'an, China
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Tan QC, Liu ZX, Zhao Y, Huang XY, Bai H, Yang Z, Zhao X, Du CF, Lei W, Wu ZX. Biomechanical comparison of four types of instrumentation constructs for revision surgery in lumbar adjacent segment disease: A finite element study. Comput Biol Med 2021; 134:104477. [PMID: 34010793 DOI: 10.1016/j.compbiomed.2021.104477] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/28/2021] [Accepted: 05/04/2021] [Indexed: 02/05/2023]
Abstract
BACKGROUND Different constructs are applied in revision surgery (RS) for adjacent segment disease (ASD) aiming to further decompress and fixate the affected segment(s) in two ways: replacing or preserving the primary implants. This study aimed to compare the biomechanical properties of four constructs with different configurations. METHODS An T12-L5 finite element (FE) model was constructed and validated. Primary surgery was performed at L4-L5 and instrumented from L3 to L5. Thereafter, RS was undertook by decompressing L2-L3 and fixated with implant-replacing construct A, or implant-preserving construct B, C or D. Range of motion (ROM) and intervertebral disc pressure (IDP) were compared. Maximum von Mises stress on the rods between Construct A and B was evaluated. RESULTS An obvious reduction of ROM was observed when the FE model was instrumented with four constructs respectively. The overall changing characteristics of ROM were approximately identical among four constructs. The changing characteristic of IDP among four constructs was similar. The degree of IDP reduction of Construct B was comparable to Construct A, while that of Construct C was comparable to Construct D. Maximum von Mises stress on the rods between Construct A and B indicated that no stress concentration was recorded at the locking part of the connector rod. CONCLUSIONS The biomechanics of implant-preserving constructs were comparable to the traditional implant-replacing construct. The location of side-by-side connector could not affect the stability of Construct C and D. Construct B might be an optimal choice in RS for less dissection, less complication and more convenience in manipulation.
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Affiliation(s)
- Quan-Chang Tan
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China; Department of Orthopedics, Air Force Hospital of Eastern Theater Command, Malujie Road No. 1, Nanjing, Jiangsu Province, 220001, PR China
| | - Zi-Xuan Liu
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, 300384, PR China; National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, 300384, China
| | - Yan Zhao
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China
| | - Xin-Yi Huang
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China
| | - Hao Bai
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China
| | - Zhao Yang
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China
| | - Xiong Zhao
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China
| | - Cheng-Fei Du
- Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, 300384, PR China; National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, 300384, China
| | - Wei Lei
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China.
| | - Zi-Xiang Wu
- Department of Orthopedics, Xijing Hospital, The Air Force Medical University, Changlexi Road No. 127, Xi'an, Shaanxi Province, 710032, PR China.
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Tan QC, Ren J, Zhong DX, Zhao X, Lei W, Wu ZX. Wandering rod: form lumbar spine into left pleural cavity with nerve irritated symptoms. Br J Neurosurg 2021; 37:1-4. [PMID: 33769177 DOI: 10.1080/02688697.2021.1904131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 03/12/2021] [Indexed: 10/21/2022]
Abstract
Spinal instrumented rod migrating from the surgical site to another remote site in the body is rare. Some cases result in organ or blood vessel injury. Most reported cases were asymptomatic until the finally injuries were generated. We report a unique case of spinal implant failure in which the rod moved from lumbar spine into chest 13 years post lumbar instrumentation. The migrated rod caused no damage to the organs in the pleural cavity but did cause an atypical pleural irritation syndrome which seemed to correlate with the mechanical irritation caused by the rod. These atypical symptoms of rod migration have not been reported previously.
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Affiliation(s)
- Quan-Chang Tan
- Department of Orthopaedics, Xijing Hospital, the Air Force Medical University, Xi'an, Shaanxi, P.R. China
- Department of Orthopaedics, Air Force Hospital of Eastern Theater Command, Nanjing, Jiangsu, P.R. China
| | - Jing Ren
- Department of Radiology, Xijing Hospital, the Air Force Medical University, Xi'an, Shaanxi, P.R. China
| | - Dai-Xing Zhong
- Department of Thoracic Surgery, Tangdu Hospital, the Air Force Medical University, Xi'an, Shaanxi, P.R. China
| | - Xiong Zhao
- Department of Orthopaedics, Xijing Hospital, the Air Force Medical University, Xi'an, Shaanxi, P.R. China
| | - Wei Lei
- Department of Orthopaedics, Xijing Hospital, the Air Force Medical University, Xi'an, Shaanxi, P.R. China
| | - Zi-Xiang Wu
- Department of Orthopaedics, Xijing Hospital, the Air Force Medical University, Xi'an, Shaanxi, P.R. China
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Tan QC, Wang D, Yang Z, Zhao XL, Zhang Y, Yan YB, Feng YF, Lei W, Zhao X, Wu ZX. Implant Preservation versus Implant Replacement in Revision Surgery for Adjacent Segment Disease After Thoracolumbar Instrumentation: A Retrospective Study of 43 Patients. World Neurosurg 2021; 150:e511-e519. [PMID: 33744424 DOI: 10.1016/j.wneu.2021.03.046] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVE To evaluate the mechanical properties of a new connector rod aiming to preserve implants in revision surgery (RS) for adjacent segment disease, a problematic complication of instrumented spinal fusion, and to assess its clinical applicability. METHODS The mechanical properties of the connector-rod construct (implant preservation) and traditional rod construct (implant replacement) were evaluated and compared. Forty-three patients underwent RS for adjacent segment disease in the thoracolumbar spine with implant preservation or replacement, and radiological and clinical outcomes were assessed. RESULTS Mechanical properties in group A were comparable to those in group B. Total mean time from prior surgery to RS was 6.86 ± 1.08 years. Surgical time and blood loss values of group A were 40.14% and 29.29% statistically significantly smaller than values of group B. In group B, 12% (3/25) of patients developed surgical site infections. In both groups, the visual analog scale leg score decreased significantly after RS. Early postoperative (at 1-month and 3-month follow-up) Oswestry Disability Index and visual analog scale back scores of group A were significantly lower than those of group B; the difference in the visual analog scale back score between groups was significant until the 6-month follow-up. No implant failures occurred, and spinal fusion was achieved in all cases. CONCLUSIONS The connector rod is considered safe and can reduce the surgical time, blood loss, risk of complications, and medical costs. Better early postoperative clinical outcomes can be achieved with the rod owing to less surgical trauma.
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Affiliation(s)
- Quan-Chang Tan
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China; Department of Orthopaedics, Air Force Hospital of Eastern Theater Command, Nanjing, China
| | - Di Wang
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Zhao Yang
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Xiao-Lei Zhao
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Yang Zhang
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Ya-Bo Yan
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Ya-Fei Feng
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Wei Lei
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Xiong Zhao
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China
| | - Zi-Xiang Wu
- Department of Orthopaedics, Xijing Hospital, Air Force Medical University, Xi'an, China.
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Yu L, Sun ZJ, Tan QC, Wang S, Wang WH, Yang XQ, Ye XJ. Thermosensitive injectable decellularized nucleus pulposus hydrogel as an ideal biomaterial for nucleus pulposus regeneration. J Biomater Appl 2020; 35:182-192. [PMID: 32338168 DOI: 10.1177/0885328220921328] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Extracellular matrix loss is one of the early manifestations of intervertebral disc degeneration. Stem cell-based tissue engineering creates an appropriate microenvironment for long term cell survival, promising for NP regeneration. We created a decellularized nucleus pulposus hydrogel (DNPH) from fresh bovine nucleus pulposus. Decellularization removed NP cells effectively, while highly preserving their structures and major biochemical components, such as glycosaminoglycan and collagen II. DNPH could be gelled as a uniform grid structure in situ at 37°C for 30 min. Adding adipose marrow-derived mesenchymal stem cells into the hydrogel for three-dimensional culture resulted in good bioactivity and biocompatibility in vitro. Meanwhile, NP-related gene expression significantly increased without the addition of exogenous biological factors. In summary, the thermosensitive and injectable hydrogel, which has low toxicity and inducible differentiation, could serve as a bio-scaffold, bio-carrier, and three-dimensional culture system. Therefore, DNPH has an outstanding potential for intervertebral disc regeneration.
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Affiliation(s)
- Lei Yu
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Zi-Jie Sun
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Quan-Chang Tan
- Air Force Hospital of PLA Eastern Theater Command, Nanjing, Jiangsu, China
| | - Shuang Wang
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Wei-Heng Wang
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai, China
| | - Xiang-Qun Yang
- Department of Anatomy, Institute of Biomedical Engineering, Second Military Medical University, Shanghai, China
| | - Xiao-Jian Ye
- Department of Orthopaedics, Changzheng Hospital, Second Military Medical University, Shanghai, China
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Tan QC, Wu JW, Peng F, Zang Y, Li Y, Zhao X, Lei W, Wu ZX. Augmented PMMA distribution: improvement of mechanical property and reduction of leakage rate of a fenestrated pedicle screw with diameter-tapered perforations. J Neurosurg Spine 2016; 24:971-7. [PMID: 26849712 DOI: 10.3171/2015.10.spine141275] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE This study investigated the optimum injection volume of polymethylmethacrylate (PMMA) to augment a novel fenestrated pedicle screw (FPS) with diameter-tapered perforations in the osteoporotic vertebral body, and how the distribution characteristics of PMMA affect the biomechanical performance of this screw. METHODS Two types of FPSs were designed (FPS-A, composed of 6 perforations with an equal diameter of 1.2 mm; and FPS-B, composed of 6 perforations each with a tapered diameter of 1.5 mm, 1.2 mm, and 0.9 mm from tip to head. Each of 28 human cadaveric osteoporotic vertebrae were randomly assigned to 1 of 7 groups: FPS-A1.0: FPS-A+1.0 ml PMMA; FPS-A1.5: FPS-A+1.5 ml PMMA; FPS-A2.0: FPS-A+2.0 ml PMMA; FPS-B1.0: FPS-B+1.0 ml PMMA; FPS-B1.5: FPS-B+1.5 ml PMMA; FPS-B2.0: FPS-B+2.0 ml PMMA; and conventional pedicle screws (CPSs) without PMMA. After the augmentation, 3D CT was performed to assess the cement distribution characteristics and the cement leakage rate. Axial pullout tests were performed to compare the maximum pullout force thereafter. RESULTS The CT construction images showed that PMMA bone cement formed a conical mass around FPS-A and a cylindrical mass around FPS-B. When the injection volume was increased from 1.0 ml to 2.0 ml, the distribution region of the PMMA cement was enlarged, the PMMA was distributed more posteriorly, and the risk of leakage was increased. When the injection volume reached 2.0 ml, the risk of cement leakage was lower for screws having diameter-tapered perforations. The pullout strengths of the augmented FPS-A groups and FPS-B groups were higher than that of the CPS group (p < 0.0001). All FPS-B groups had a higher pullout strength than the FPS-A groups. CONCLUSIONS The diameter of the perforations affects the distribution of PMMA cement. The diameter-tapered design enabled PMMA to form larger bone-PMMA interfaces and achieve a relatively higher pullout strength, although statistical significance was not reached. Study results indicated 1.5-ml of PMMA was a conservative volume for PMMA augmentation; more cement injection would significantly increase the risk of cement leakage.
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Affiliation(s)
- Quan-Chang Tan
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and.,Department of Orthopaedics, 454 Hospital of PLA, Nanjing, Jiangsu Province, People's Republic of China
| | - Jian-Wei Wu
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
| | - Fei Peng
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
| | - Yuan Zang
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
| | - Yang Li
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
| | - Xiong Zhao
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
| | - Wei Lei
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
| | - Zi-Xiang Wu
- Department of Orthopaedics, Xijing Hospital, the Fourth Military Medical University, Xi'an Shaanxi Province; and
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