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Chen Z, Han J, Zhang J, Peng Y, Guo L, Chen S, Jin Z. Tibial post loading increases the risk of aseptic loosening of posterior-stabilized tibial prosthesis. Proc Inst Mech Eng H 2024:9544119241272756. [PMID: 39177049 DOI: 10.1177/09544119241272756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2024]
Abstract
Aseptic loosening is the primary cause of failure following posterior-stabilized total knee arthroplasty. It is unclear whether tibial post loading of posterior-stabilized prosthesis increases the risk of aseptic loosening of the tibial prosthesis. The purpose of this study is to investigate the biomechanical effects of tibial post loading on the tibial prosthesis fixation interface during level walking, squatting, stair descent, and standing up-sitting down activities. In this paper, finite element models with and without post were established to compare the effects of tibial post loading on the von Mises stress of the proximal tibia, shear stress of the cement, and the bone-prosthesis interface micromotion during four physiological activities. The tibial post loading had an insignificant influence on tibial biomechanics and bone-prosthesis interface micromotion during leveling walking activity. However, compared to the insert without post condition, tibial post loading significantly increased the maximum tibial von Mises stress, the maximum shear stress in the medial of cement, and the bone-prosthesis interface peak micromotion by 912.84%, 612.77%, and 921.09%, respectively, at the moment of the maximum flexion angle for the stair descent activity, and 637.92%, 351.43%, and 519.13%, respectively, at the moment of the maximum flexion angle for the standing up-sitting down activity. Tibial post loading increased the risk of postoperative aseptic loosening of tibial prosthesis in patients with posterior-stabilized total knee arthroplasty, and it was recommended that the post-cam contact mechanism of posterior-stabilized prosthesis should be optimized to reduce the biomechanical impact of tibial post loading on tibial prosthesis fixation.
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Affiliation(s)
- Zhenxian Chen
- Key Laboratory of Road Construction Technology and Equipment of MOE, Chang'an University, Xi'an, Shaanxi, China
| | - Jianian Han
- Key Laboratory of Road Construction Technology and Equipment of MOE, Chang'an University, Xi'an, Shaanxi, China
| | - Jing Zhang
- Key Laboratory of Road Construction Technology and Equipment of MOE, Chang'an University, Xi'an, Shaanxi, China
| | - Yinghu Peng
- CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences, Shenzhen, China
| | - Lei Guo
- Key Laboratory of Road Construction Technology and Equipment of MOE, Chang'an University, Xi'an, Shaanxi, China
| | - Shibin Chen
- Key Laboratory of Road Construction Technology and Equipment of MOE, Chang'an University, Xi'an, Shaanxi, China
| | - Zhongmin Jin
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, China
- Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds, UK
- Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
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Wu D, Wang Q, Tsai HK, Zhou S, Zheng D, Jiang Q, Xu Z. Bond strength of metal-free polyether-ether-ketone knee prostheses compared to metal knee prostheses with bone cement: A preliminary in vitro study. J Orthop Surg (Hong Kong) 2023; 31:10225536231217537. [PMID: 37997347 DOI: 10.1177/10225536231217537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2023] Open
Abstract
BACKGROUND Total knee arthroplasty is the most effective treatment for advanced-stage knee arthritis, and the majority of knee prostheses are made of metal. Nevertheless, metal prostheses still have several problems. The objective of this study is to introduce new metal-free knee prostheses made of polyether-ether-ketone (PEEK) and to compare their cement bond strength with metal prostheses. METHODS Twelve sets of knee prostheses were divided into four groups (unloaded PEEK, unloaded Metal, 10 million cycles (MC) PEEK, 10 MC Metal, N = 3 each), and then attached to composite bones using bone cement. Both the 10 MC PEEK and 10 MC Metal groups were subjected to dynamic gait simulations of 10 MC, whereas the other two sets were not. Afterwards, a pull-off strength test was performed on the femoral prostheses and a shear strength test was performed on the tibial prostheses. RESULTS No apparent cracks were observed in the bone cement after subjecting the PEEK and Metal groups to 10 million cycles of dynamic simulation. No statistically significant differences were observed (p > .05) in the strength tests for unloaded PEEK vs. unloaded Metal, 10 MC PEEK vs.10 MC Metal in the femoral pull-off test, and for unloaded PEEK vs. unloaded Metal in the tibial shear test. The shear strength of 10 MC PEEK was significantly lower (p < .05) compared to that of 10 MC Metal. CONCLUSIONS By comparing the force analysis of previous investigations on knee prostheses with the failure pattern observed in the PEEK knee prosthesis of this study, which replicates that of the metal prosthesis. We believe that the combination of the peek knee prosthesis with bone cement is reliable. We anticipate that metal-free PEEK knee prostheses will find application in Total Knee Arthroplasty (TKA) in the future, thereby benefiting patients.
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Affiliation(s)
- Dengxian Wu
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, PR China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu, PR China
- Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China
| | - Qianjin Wang
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, PR China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu, PR China
- Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China
| | - Hung-Kang Tsai
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, PR China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu, PR China
- Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China
| | - Sheng Zhou
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, PR China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu, PR China
- Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China
| | - Donggui Zheng
- Suzhou SinoMed Biomaterials Co., Ltd, Suzhou, Jiangsu, PR China
| | - Qing Jiang
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, PR China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu, PR China
- Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China
| | - Zhihong Xu
- Division of Sports Medicine and Adult Reconstructive Surgery, Department of Orthopedic Surgery, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, Jiangsu, PR China
- State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, Jiangsu, PR China
- Branch of National Clinical Research Center for Orthopedics, Sports Medicine and Rehabilitation, PR China
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Cox ZC, Engstrom SM, Shinar AA, Polkowski GG, Mason JB, Martin JR. Is cement mantle thickness a primary cause of aseptic tibial loosening following primary total knee arthroplasty? Knee 2023; 40:305-312. [PMID: 36592499 DOI: 10.1016/j.knee.2022.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 11/27/2022] [Accepted: 12/13/2022] [Indexed: 01/01/2023]
Abstract
BACKGROUND Aseptic tibial loosening following primary total knee replacement is one of the leading causes of long-term failure. Cement mantle thickness has been implicated as a source of aseptic tibial loosening. Therefore, the following study was designed to determine (1) what is the cement mantle thickness in patients that develop aseptic tibial loosening, and (2) is there a difference in cement mantle thickness based on the interface of failure? METHOD This retrospective cohort included 216 patients revised for aseptic tibial loosening. Patient demographics, operative data, and clinical outcomes were recorded. A preoperative radiographic assessment was performed to determine the interface of failure and the thickness of the cement mantle using the Knee Society Radiographic Evaluation System zones. RESULTS The average patient age was 65 years and body mass index was 33.7 kg/m2. 203 patients demonstrated radiographic failure at the implant-cement interface and 13 patients demonstrated failure at the cement-bone interface. The average cement mantle thickness of each radiographic zone for the entire cohort on the AP and lateral views was 4.4 and 4.5 mm, respectively. The average cement mantle thickness of patients that developed failure at the implant-cement interface was significantly greater than patients that failed at the cement-bone interface in each radiographic zone (p < 0.001). CONCLUSIONS Patients that develop implant loosening at the cement-bone interface were noted to have a significantly decreased cement mantle compared to patients that failed at the implant-cement interface. Methods for decreasing tibial implant loosening should likely focus on improving the fixation at the implant-cement interface.
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Affiliation(s)
- Zach C Cox
- OrthoCarolina Hip and Knee Center, Charlotte, NC, 250 N Caswell Rd Suit 200A, Charlotte, NC 28207, USA
| | - Stephen M Engstrom
- Vanderbilt University Medical Center, 1215 21st Ave S Suite 4200, Nashville, TN 37232, USA
| | - Andrew A Shinar
- Vanderbilt University Medical Center, 1215 21st Ave S Suite 4200, Nashville, TN 37232, USA
| | - Gregory G Polkowski
- Vanderbilt University Medical Center, 1215 21st Ave S Suite 4200, Nashville, TN 37232, USA
| | - J Bohannon Mason
- OrthoCarolina Hip and Knee Center, Charlotte, NC, 250 N Caswell Rd Suit 200A, Charlotte, NC 28207, USA
| | - J Ryan Martin
- Vanderbilt University Medical Center, 1215 21st Ave S Suite 4200, Nashville, TN 37232, USA.
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Grupp TM, Schilling C, Fritz B, Puente Reyna AL, Rusch S, Taunt C, Mihalko WM. Endurance Behavior of Cemented Tibial Tray Fixation Under Anterior Shear and Internal-External Torsional Shear Testing: A New Methodological Approach. J Arthroplasty 2022; 37:2272-2281. [PMID: 35588902 DOI: 10.1016/j.arth.2022.05.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/24/2022] [Accepted: 05/10/2022] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Early total knee arthroplasty failures continue to surface in the literature. Cementation technique and implant design are two of the most important scenarios that can affect implant survivorship. Our objectives were to develop a more suitable preclinical test to evaluate the endurance of the implant-cement-bone interface under anterior shear and internal-external (I/E) torsional shear testing condition in a biomechanical sawbones. METHODS Implants tested included the AS VEGA System PS and the AS Columbus CR/PS (Aesculap AG, Germany), with zirconium nitride (ZrN) coating. Tibial implants were evaluated under anterior shear and I/E torsional shear conditions with 6 samples in 4 test groups. For the evaluation of the I/E torsional shear endurance behavior, a test setup was created allowing for clinically relevant I/E rotation with simultaneous high axial/tibio-femoral load. The test was performed with an I/E displacement of ±17.2°, for 1 million cycles with an axial preload of 3,000 N. RESULTS After the anterior shear test an implant-cement-bone fixation strength for the AS VEGA System tibial tray of 2,674 ± 754 N and for the AS Columbus CR/PS tibial tray of 2,177 ± 429 N was determined (P = .191). After I/E rotational shear testing an implant-cement-bone fixation strength for the AS VEGA System PS tray of 2,561 ± 519 N and for the AS Columbus CR/PS tray of 2,824 ± 515 N was resulted (P = .39). CONCLUSION Both methods had varying degrees of failure modes from debonding to failure of the sawbones foam. These two intense biomechanical loading tests are more strenuous and more representative of clinical activity.
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Affiliation(s)
- Thomas M Grupp
- Aesculap AG Research & Development, Tuttlingen, Germany; Ludwig Maximilians University Munich, Department of Orthopaedic and Trauma Surgery, Musculoskeletal University Center Munich (MUM), Campus Grosshadern, Munich, Germany
| | | | | | | | - Sabine Rusch
- Aesculap AG Research & Development, Tuttlingen, Germany
| | | | - William M Mihalko
- Campbell Clinic Department of Orthopaedic Surgery & Biomedical Eng., University of Tennessee Health Science Center, Memphis, Tennessee
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Rodríguez-Collell JR, Mifsut D, Ruiz-Sauri A, Rodríguez-Pino L, González-Soler EM, Valverde-Navarro AA. Improving the cementation of the tibial component in knee arthroplasty : a study of four techniques in the cadaver. Bone Joint Res 2021; 10:467-473. [PMID: 34340533 PMCID: PMC8414436 DOI: 10.1302/2046-3758.108.bjr-2020-0524.r1] [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] [Indexed: 11/05/2022] Open
Abstract
AIMS The main objective of this study is to analyze the penetration of bone cement in four different full cementation techniques of the tibial tray. METHODS In order to determine the best tibial tray cementation technique, we applied cement to 40 cryopreserved donor tibiae by four different techniques: 1) double-layer cementation of the tibial component and tibial bone with bone restrictor; 2) metallic cementation of the tibial component without bone restrictor; 3) bone cementation of the tibia with bone restrictor; and 4) superficial bone cementation of the tibia and metallic keel cementation of the tibial component without bone restrictor. We performed CT exams of all 40 subjects, and measured cement layer thickness at both levels of the resected surface of the epiphysis and the endomedular metaphyseal level. RESULTS At the epiphyseal level, Technique 2 gave the greatest depth compared to the other investigated techniques. At the endomedular metaphyseal level, Technique 1 showed greater cement penetration than the other techniques. CONCLUSION The best metaphyseal cementation technique of the tibial component is bone cementation with cement restrictor. Additionally, if full tibial component cementation is to be done, the cement volume used should be about 40 g of cement, and not the usual 20 g. Cite this article: Bone Joint Res 2021;10(8):467-473.
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Affiliation(s)
| | - Damian Mifsut
- Department of Surgery, University of Valencia, Valencia, Spain
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Schierjott RA, Hettich G, Ringkamp A, Baxmann M, Morosato F, Damm P, Grupp TM. A method to assess primary stability of acetabular components in association with bone defects. J Orthop Res 2020; 38:1769-1778. [PMID: 31944372 DOI: 10.1002/jor.24591] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 01/13/2020] [Indexed: 02/04/2023]
Abstract
The objectives of this study were to develop a simplified acetabular bone defect model based on a representative clinical case, derive four bone defect increments from the simplified defect to establish a step-wise testing procedure, and analyze the impact of bone defect and bone defect filling on primary stability of a press-fit cup in the smallest defined bone defect increment. The original bone defect was approximated with nine reaming procedures and by exclusion of specific procedures, four defect increments were derived. The smallest increment was used in an artificial acetabular test model to test primary stability of a press-fit cup in combination with bone graft substitute (BGS). A primary acetabular test model and a defect model without filling were used as reference. Load was applied in direction of level walking in sinusoidal waveform with an incrementally increasing maximum load (300 N/1000 cycles from 600 to 3000 N). Relative motions (inducible displacement, migration, and total motion) between cup and test model were assessed with an optical measurement system. Original and simplified bone defect volume showed a conformity of 99%. Maximum total motion in the primary setup at 600 N (45.7 ± 5.6 µm) was in a range comparable to tests in human donor specimens (36.0 ± 16.8 µm). Primary stability was reduced by the bone defect, but could mostly be reestablished by BGS-filling. The presented method could be used as platform to test and compare different treatment strategies for increasing bone defect severity in a standardized way.
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Affiliation(s)
- Ronja A Schierjott
- Research & Development, Aesculap AG, Am Aesculap-Platz, Tuttlingen, Germany.,Department of Orthopaedic Surgery, Physical Medicine & Rehabilitation, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Georg Hettich
- Research & Development, Aesculap AG, Am Aesculap-Platz, Tuttlingen, Germany
| | - Alexandra Ringkamp
- Department of Biomechatronics, Faculty of Mechanical Engineering, Technische Universität Ilmenau, Ilmenau, Germany
| | - Marc Baxmann
- Research & Development, Aesculap AG, Am Aesculap-Platz, Tuttlingen, Germany
| | - Federico Morosato
- Department of Industrial Engineering, School of Engineering and Architecture, Università di Bologna, Bologna, Italy
| | - Philipp Damm
- Julius Wolff Institute, Joint Loading & Musculoskeletal Analysis, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Thomas M Grupp
- Research & Development, Aesculap AG, Am Aesculap-Platz, Tuttlingen, Germany.,Department of Orthopaedic Surgery, Physical Medicine & Rehabilitation, Ludwig-Maximilians-University Munich, Munich, Germany
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Tibial Implant Fixation Behavior in Total Knee Arthroplasty: A Study With Five Different Bone Cements. J Arthroplasty 2020; 35:579-587. [PMID: 31653466 DOI: 10.1016/j.arth.2019.09.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 08/15/2019] [Accepted: 09/13/2019] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND The objectives of this study are to (1) evaluate if there is a potential difference in cemented implant fixation strength between tibial components made out of cobalt-chromium (CrCoMo) and of a ceramic zirconium nitride (ZrN) multilayer coating and to (2) test their behavior with 5 different bone cements in a standardized in vitro model for testing of the implant-cement-bone interface conditions. We also analyzed (3) whether initial fixation strength is a function of timing of the cement apposition and component implantation by an early, mid-term, and late usage within the cement-specific processing window. METHODS An in vitro study using a synthetic polyurethane foam model was performed to investigate the implant fixation strength after cementation of tibial components by a push-out test. A total of 20 groups (n = 5 each) was used: Vega PS CrCoMo tibia and Vega PS ZrN tibia with the bone cements BonOs R, SmartSet HV, Cobalt HV, Palacos R, and Surgical Simplex P, respectively, using mid-term cement apposition. Three different cement apposition times-early, mid-term, and late usage-were tested with a total of 12 groups (n = 5 each) with the bone cements BonOs R and SmartSet HV. RESULTS There was no significant difference in implant-cement-bone fixation strength between CrCoMo and ZrN multilayer-coated Vega tibial trays tested with 5 different commonly used bone cements. CONCLUSION Apposition of bone cements and tibial tray implantation in the early to mid of the cement-specific processing window is beneficial in regard to interface fixation in TKA.
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Stilling M, Mechlenburg I, Jepsen CF, Rømer L, Rahbek O, Søballe K, Madsen F. Superior fixation and less periprosthetic stress-shielding of tibial components with a finned stem versus an I-beam block stem: a randomized RSA and DXA study with minimum 5 years' follow-up. Acta Orthop 2019; 90:165-171. [PMID: 30669918 PMCID: PMC6461099 DOI: 10.1080/17453674.2019.1566510] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Background and purpose - The stem on the tibial component of total knee arthroplasty provides mechanical resistance to lift-off, shear forces, and torque. We compared tibial components with finned stems (FS) and I-beam block stems (IS) to assess differences in implant migration. Patients and methods - In a patient-blinded RCT, 54 patients/knees (15 men) with knee osteoarthritis at a mean age of 77 years (70-90) were randomly allocated to receive tibial components with either a FS (n = 27) or an IS (n = 27). Through 5 to 7 years' follow-up, implant migration was measured with RSA, periprosthetic bone mineral density (BMD) was measured with DXA, and surgeons reported American Knee Society Score (AKSS). Results - At minimum 5 years' follow-up, maximum total point motion (MTPM) was higher (p = 0.04) for IS (1.48 mm, 95% CI 0.81-2.16) than for FS (0.85 mm, CI 0.38-1.32) tibial components. Likewise, total rotation (TR) was higher (p = 0.03) for IS (1.51˚, CI 0.78-2.24) than for FS (0.81˚, CI 0.36-1.27). Tibial components with IS externally rotated 0.50° (CI -0.06 to 1.06) while FS internally rotated 0.09° (CI -0.20 to 0.38) (p = 0.03). Periprosthetic bone stress-shielding was higher (p < 0.01) up to 2 years' follow-up for IS compared with FS in the regions medial to the stem (-13% vs. -2%) and posterior to the stem (-13% vs. -2%). Below the stem bone loss was also higher (p = 0.01) for IS compared with FS (-6% vs. +1%) up to 1-year follow-up. Knee score improved similarly in both groups up to 5 years' follow-up. Interpretation - Periprosthetic bone stress-shielding medial and posterior to the stem until 2 years, and tibial component migration at 5 years, was less for a finned compared with an I-shaped block stem design.
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Affiliation(s)
- Maiken Stilling
- Orthopaedic Research Unit, Aarhus University Hospital;; ,Department of Orthopaedic Surgery, Aarhus University Hospital; ,Department of Clinical Medicine, Aarhus University, Denmark,Correspondence:
| | - Inger Mechlenburg
- Orthopaedic Research Unit, Aarhus University Hospital;; ,Centre of Research in Rehabilitation (CORIR), Department of Clinical Medicine, Aarhus University Hospital and Aarhus University;
| | | | - Lone Rømer
- Department of Radiology, Aarhus University Hospital;
| | - Ole Rahbek
- Department of Orthopaedic Surgery, Aarhus University Hospital; ,Department of Clinical Medicine, Aarhus University, Denmark
| | - Kjeld Søballe
- Department of Orthopaedic Surgery, Aarhus University Hospital; ,Department of Clinical Medicine, Aarhus University, Denmark
| | - Frank Madsen
- Department of Orthopaedic Surgery, Aarhus University Hospital;
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