1
|
He B, Zhang X, Peng S, Zeng D, Chen H, Liang Z, Zhong H, Ouyang H. Prediction of intraoperative press-fit stability of the acetabular cup in total hip arthroplasty using radiomics-based machine learning models. Eur J Radiol 2024; 181:111751. [PMID: 39321656 DOI: 10.1016/j.ejrad.2024.111751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 09/03/2024] [Accepted: 09/17/2024] [Indexed: 09/27/2024]
Abstract
BACKGROUND Preoperative prediction of the acetabular cup press-fit stability in total hip arthroplasty is necessary for clinical decision-making. This study aims to establish and validate machine learning models to investigate the feasibility of predicting the intraoperative press-fit stability of the acetabular cup in total hip arthroplasty (THA). METHODS 226 patients who underwent primary THA from 2018 to 2022 in our hospital were retrospectively enrolled. Patients were divided into press-fit stable or unstable groups according to the intraoperative pull-out test of the implanted cup. Then, they were randomly assigned to the training or test cohort in an 8:2 ratio. We used 3Dslicer software to segment the region of interest (ROI) of the patient's bilateral hip X-ray to extract radiomics features. The least absolute shrinkage and selection operator (LASSO) regression was used in our feature selection. Finally, four machine learning models were employed in this study, including support vector machine (SVM), random forest (RF), logistic regression (LR), and XGBoost (XGB). Decision curve analysis (DCA), and receiver operating characteristic (ROC) curves of the models were plotted. The area under the curve (AUC), diagnostic accuracy, sensitivity, and specificity were calculated as well. The AUCs of the four models were compared using the DeLong test. RESULTS Twenty-seven valuable radiomics features were determined by dimensionality reduction and selection. Regarding to the DeLong test, the AUC of the XGB model was significantly different from those of the other three models. (p < 0.05). Among all models, the XGB model exhibited the best performance with an AUC of 0.823 (95 % CI: 0.711-0.919) in the test cohort and showed optimal clinical efficacy according to the DCA. CONCLUSION Machine learning models based on X-ray radiomics can accurately predict the intraoperative press-fit stability of implanted cups preoperatively, providing surgeons with valuable information to lower the complication risk in THA.
Collapse
Affiliation(s)
- Bin He
- Joint Surgery Department of Orthopedic Center, Affiliated Hospital of Guangdong Medical University Zhanjiang 524001, Guangdong, China; Department of Orthopedic, Southwest Hospital Jiangbei Area (The 958th Hospital of Chinese People's Liberation Army), Chongqing 400020, China
| | - Xin Zhang
- Joint Surgery Department of Orthopedic Center, Affiliated Hospital of Guangdong Medical University Zhanjiang 524001, Guangdong, China
| | - Shengwang Peng
- School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - Dong Zeng
- School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China
| | - Haicong Chen
- Joint Surgery Department of Orthopedic Center, Affiliated Hospital of Guangdong Medical University Zhanjiang 524001, Guangdong, China
| | - Zhenming Liang
- Joint Surgery Department of Orthopedic Center, Affiliated Hospital of Guangdong Medical University Zhanjiang 524001, Guangdong, China
| | - Huan Zhong
- Joint Surgery Department of Orthopedic Center, Affiliated Hospital of Guangdong Medical University Zhanjiang 524001, Guangdong, China.
| | - Hanbin Ouyang
- Joint Surgery Department of Orthopedic Center, Affiliated Hospital of Guangdong Medical University Zhanjiang 524001, Guangdong, China.
| |
Collapse
|
2
|
Yoshida K, Fukushima K, Sakai R, Uchiyama K, Takahira N, Ujihira M. A novel primary stability test method for artificial acetabular shells considering vertical load during level walking and shell position. PLoS One 2024; 19:e0296919. [PMID: 38421998 PMCID: PMC10903903 DOI: 10.1371/journal.pone.0296919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 12/22/2023] [Indexed: 03/02/2024] Open
Abstract
Uncemented acetabular shell primary stability is essential for optimal clinical outcomes. Push-out testing, rotation testing, and lever-out testing are major evaluation methods of primary stability between the shell and bone. However, these test methods do not consider shell loads during daily activity and shell installation angle. This study proposes a novel evaluation method of acetabular shell primary stability considering load during level walking and acetabular installation angles such as inclination and anteversion. To achieve this, a novel primary stability test apparatus was designed with a shell position of 40° acetabular inclination and 20° anteversion. The vertical load, corresponding to walking load, was set to 3 kN according to ISO 14242-1, which is the wear test standard for artificial hip joints. The vertical load was applied by an air cylinder controlled by a pressure-type electro-pneumatic proportional valve, with the vertical load value monitored by a load cell. Torque was measured when angular displacement was applied in the direction of extension during the application of vertical load. For comparison, we also measured torque using the traditional lever-out test. The novel primary stability test yielded significantly higher primary stabilities; 5.4 times greater than the lever-out test results. The novel primary stability test failure mode was more similar to the clinical failure than the traditional lever-out test. It is suggested that this novel primary stability test method, applying physiological walking loads and extension motions to the acetabular shell, better reflects in vivo primary stability than the traditional lever-out test.
Collapse
Affiliation(s)
- Kazuhiro Yoshida
- Department of Medical Engineering and Technology, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Kensuke Fukushima
- Department of Orthopaedic Surgery, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Rina Sakai
- Department of Medical Engineering and Technology, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Katsufumi Uchiyama
- Department of Orthopaedic Surgery, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Naonobu Takahira
- Department of Orthopaedic Surgery, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Masanobu Ujihira
- Department of Medical Engineering and Technology, Kitasato University, Sagamihara, Kanagawa, Japan
| |
Collapse
|
3
|
Hidaka R, Matsuda K, Mochizuki H, Kawano H. Initial stability of cementless acetabular cups using robotic-assisted total hip arthroplasty compared with the conventional manual technique: An in vitro biomechanical study. Int J Med Robot 2023:e2613. [PMID: 38108101 DOI: 10.1002/rcs.2613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/28/2023] [Accepted: 12/06/2023] [Indexed: 12/19/2023]
Abstract
BACKGROUND The aim of this study is to determine whether the initial stability of a cementless cup with the Mako system is superior to that of a conventional manual technique using bone models. METHODS The bone models were prepared using a polyurethane foam block. Two hemispherical cementless cups (highly porous titanium cup [Trident II Tritanium, Stryker] and hydroxyapatite-coated titanium cup [Trident HA, Stryker]) were implanted using the Mako system. The torque of the cups was measured by rotational and lever-out torque testing and compared with that of a conventional manual technique. RESULTS The two types of cups that were implanted using the Mako system demonstrated significantly higher mean rotational torque than that of the manual technique (p < 0.01, p = 0.01, respectively). CONCLUSIONS This study provides the advantage of the initial stability of a cementless hemispherical cup implanted by the Mako system compared with that of the conventional manual technique.
Collapse
Affiliation(s)
- Ryo Hidaka
- Department of Orthopedic Surgery, Teikyo University School of Medicine, Tokyo, Japan
| | - Kenta Matsuda
- Department of Orthopedic Surgery, Teikyo University School of Medicine, Tokyo, Japan
| | - Hidetaka Mochizuki
- Department of Orthopedic Surgery, Teikyo University School of Medicine, Tokyo, Japan
| | - Hirotaka Kawano
- Department of Orthopedic Surgery, Teikyo University School of Medicine, Tokyo, Japan
| |
Collapse
|
4
|
Gautreaux M, Kautz S, Martin Z, Morgan E, Barton RS, Dubose M, McBride H, Solitro GF. Acetabular Wall Weakening in Total Hip Arthroplasty: A Pilot Study. PATHOPHYSIOLOGY 2023; 30:83-91. [PMID: 37092522 PMCID: PMC10123709 DOI: 10.3390/pathophysiology30020008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/08/2023] [Accepted: 03/08/2023] [Indexed: 04/25/2023] Open
Abstract
Total hip arthroplasty is a widely performed operation allowing disabled patients to improve their quality of life to a degree greater than any other elective procedure. Planning for a THA requires adequate patient assessment and preoperative characterizations of acetabular bone loss via radiographs and specific classification schemes. Some surgeons may be inclined to ream at a larger diameter thinking it would lead to a more stable press-fit, but this could be detrimental to the acetabular wall, leading to intraoperative fracture. In the attempt to reduce the incidence of intraoperative fractures, the current study aims to identify how increased reaming diameter degrades and weakens the acetabular rim strength. We hypothesized that there is proportionality between the reaming diameter and the reduction in acetabular strength. To test this hypothesis, this study used bone surrogates, templated from CT scans, and reamed at different diameters. The obtained bone surrogate models were then tested using an Intron 8874 mechanical testing machine (Instron, Norwood, MA) equipped with a custom-made fixture. Analysis of variance (ANOVA) was used to identify differences among reamed diameters while linear regression was used to identify the relationship between reamed diameters and acetabular strength. We found a moderate correlation between increasing reaming diameter that induced thinning of the acetabular wall and radial load damage. For the simplified acetabular model used in this study, it supported our hypothesis and is a promising first attempt in providing quantitative data for acetabular weakening induced by reaming.
Collapse
Affiliation(s)
- Madeline Gautreaux
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - Steven Kautz
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - Zashiana Martin
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - Edward Morgan
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - R Shane Barton
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - Matthew Dubose
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - Hayden McBride
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| | - Giovanni F Solitro
- Department of Orthopedic Surgery, LSU Health Shreveport, 1501 Kings Hwy, Shreveport, LA 71103, USA
| |
Collapse
|
5
|
Ruhr M, Baetz J, Pueschel K, Morlock MM. Influence of acetabular cup thickness on seating and primary stability in total hip arthroplasty. J Orthop Res 2022; 40:2139-2146. [PMID: 34855229 DOI: 10.1002/jor.25232] [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: 09/03/2021] [Revised: 11/05/2021] [Accepted: 11/20/2021] [Indexed: 02/04/2023]
Abstract
Insufficient primary stability of acetabular hip cups is a complication resulting in early cup loosening. Available cup designs vary in terms of wall thickness, potentially affecting implant fixation. This study investigated the influence of different wall thicknesses on the implantation process and the resulting primary stability using excised human acetabula. Implantations were performed using a powered impaction device providing consistent energy with each stroke. Two different wall thicknesses were compared in terms of seating progress, polar gap remaining after implantation, bone-to-implant contact area, cup deflection, and lever out moment. Thin-walled cups showed higher lever out resistance (p < 0.001) and smaller polar gaps (p < 0.001) with larger bone contact toward the dome of the cup (p < 0.001) compared to thick-walled cups. Small seating steps at the end of the impaction process were observed if a high number of strokes were needed to seat the cup (p = 0.045). A high number of strokes led to a strain release of the cup during the final strokes (p = 0.003). This strain release is indicative for over-impaction of the cup associated with bone damage and reduced primary stability. Adequate cup seating can be achieved with thin-walled cups with lower energy input in comparison to thicker ones. Thin-walled cups showed improved primary stability and enable implantation with lower energy input, reducing the risk of over-impaction and bone damage. Additional strokes should be avoided as soon as no further seating progress has been observed.
Collapse
Affiliation(s)
- Miriam Ruhr
- Institute of Biomechanics, Hamburg University of Technology, Hamburg, Germany
| | - Johanna Baetz
- Institute of Biomechanics, Hamburg University of Technology, Hamburg, Germany
| | - Klaus Pueschel
- Department of Legal Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michael M Morlock
- Institute of Biomechanics, Hamburg University of Technology, Hamburg, Germany
| |
Collapse
|
6
|
Wang Y, Wang M, Li C, Nakamura Y, Deng L, Yamako G, Chosa E, Pan C. Biomechanical effect of metal augment and bone graft on cup stability for acetabular reconstruction of total hip arthroplasty in hip dysplasia: a finite element analysis. BMC Musculoskelet Disord 2022; 23:277. [PMID: 35321681 PMCID: PMC8943934 DOI: 10.1186/s12891-022-05168-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 02/23/2022] [Indexed: 11/10/2022] Open
Abstract
Background Different methods of acetabular reconstruction with total hip arthroplasty (THA) for Crowe II and III of adult developmental dysplasia of the hip (DDH) acetabular bone defect have been implemented clinically. However, the biomechanical effect of different augmented materials for acetabular reconstruction in THA on shell stability has never been discussed. Methods In the present study, autologous bone graft (BG)and metal (Ti6Al4V) augment (MA) were simulated with several acetabular bone defect models of DDH in THA. The contact pressure and micromotion between the shell and host bone were measured for evaluating the shell stability using a finite element method. Results The peak contact stress between shell and host bone was higher in the MA situation (12.45 vs 8.71 MPa). And the load transfer path was different, for BG models, the high local contact stresses were found at the junction of bone graft and host bone while for MA models the concentrated contact stresses were at the surface of MA. The peak relative micromotion between shell and host bone was higher in the MA situation (12.61 vs 11.13 µm). However, the peak micromotion decreased in the contact interface of MA and cup compared to the BG models. Conclusions The higher micromotion was found in MA models, however, enough for bone ingrowth, and direct stronger fixation was achieved in the MA-cup interface. Thus, we recommended the MA can be used as an option, even for Crowe III, however, the decision should be made from clinical follow-up results.
Collapse
Affiliation(s)
- Yuzhu Wang
- Department of Orthopaedic Surgery, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China.,Department of Orthopaedic Surgery, Faculty of Medicine, University of Miyazaki, Miyazaki, Miyazaki, Japan
| | - Mincong Wang
- Department of Orthopaedic Surgery, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China
| | - Chengguo Li
- Department of Orthopaedic Surgery, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China
| | - Yoshihiro Nakamura
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Miyazaki, Miyazaki, Miyazaki, Japan
| | - Liwei Deng
- Department of Radiology, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China
| | - Go Yamako
- Department of Mechanical Engineering, Faculty of Engineering, University of Miyazaki, Miyazaki, Miyazaki, Japan
| | - Etsuo Chosa
- Department of Orthopaedic Surgery, Faculty of Medicine, University of Miyazaki, Miyazaki, Miyazaki, Japan
| | - Chenglong Pan
- Department of Orthopaedic Surgery, The Fifth Affiliated Hospital of Southern Medical University, Guangzhou, Guangdong, China.
| |
Collapse
|
7
|
Brodt S, Bischoff K, Schulze M, Nowack D, Roth A, Matziolis G. The use of acetabular screws in total hip arthroplasty and its influence on wear and periacetabular osteolysis in the long-term follow-up. INTERNATIONAL ORTHOPAEDICS 2021; 46:717-722. [PMID: 34581866 PMCID: PMC8930858 DOI: 10.1007/s00264-021-05219-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 09/13/2021] [Indexed: 11/25/2022]
Abstract
Purpose The cementless implantation of hip replacement cups may be performed with and without the additional use of acetabular screws. If the surgeon uses screws or not depends on variable factors. In general, the use of screws is intended to increase the primary stability of the cup. Whether screws increase the initial stability of the cup construct, or even reduce it in part, is the subject of considerable debate in the literature. It is also unclear whether the additional screws lead to increased wear or increased periacetabular osteolysis over the long-term course. Methods Two hundred eleven patients from a previous study with a minimum follow-up of 10.7 years were included. Of these, 68 patients with 82 total hip arthroplasties (THA) were given clinical and radiological follow-up examinations. Of these, 52 had been fitted without screws and 30 with screws. On the basis of radiographs, annual wear and osteolysis were quantified. The clinical results were recorded by means of VAS, HHS, and WOMAC scores. Results Significantly more periacetabular osteolysis was found if additive acetabular screws had been used. No difference was found in relation to the volumetric wear per year. Likewise, no difference was found with regard to the clinical scores. Conclusions The use of additive acetabular screws leads to increased osteolysis in the periacetabular bone stock. Insofar as the primary stability of the cementless cup construct allows it, no additional acetabular screws should be used. Supplementary Information The online version contains supplementary material available at 10.1007/s00264-021-05219-7.
Collapse
Affiliation(s)
- Steffen Brodt
- Department of Orthopedics, Jena University Hospital, Campus Eisenberg, Klosterlausnitzer Str. 81, 07607, Eisenberg, Germany.
| | - Kathleen Bischoff
- Department of Orthopedics, Jena University Hospital, Campus Eisenberg, Klosterlausnitzer Str. 81, 07607, Eisenberg, Germany
| | - Marcel Schulze
- Department of Orthopedics, Jena University Hospital, Campus Eisenberg, Klosterlausnitzer Str. 81, 07607, Eisenberg, Germany
| | - Dimitri Nowack
- Department of Orthopedics, Jena University Hospital, Campus Eisenberg, Klosterlausnitzer Str. 81, 07607, Eisenberg, Germany
| | - Andreas Roth
- Department Endoprosthesis/Orthopedics, Clinic of Orthopedics, Traumatology and Plastic Surgery, University Hospital Leipzig, Liebigstr. 20, 04103, Leipzig, Germany
| | - Georg Matziolis
- Department of Orthopedics, Jena University Hospital, Campus Eisenberg, Klosterlausnitzer Str. 81, 07607, Eisenberg, Germany
| |
Collapse
|
8
|
Determinants of the primary stability of cementless acetabular cup implants: A 3D finite element study. Comput Biol Med 2021; 135:104607. [PMID: 34242871 DOI: 10.1016/j.compbiomed.2021.104607] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 05/31/2021] [Accepted: 06/22/2021] [Indexed: 11/20/2022]
Abstract
Primary stability of cementless implants is crucial for the surgical success and long-term stability. However, primary stability is difficult to quantify in vivo and the biomechanical phenomena occurring during the press-fit insertion of an acetabular cup (AC) implant are still poorly understood. The aim of this study is to investigate the influence of the cortical and trabecular bone Young's moduli Ec and Et, the interference fit IF and the sliding friction coefficient of the bone-implant interface μ on the primary stability of an AC implant. For each parameter combination, the insertion of the AC implant into the hip cavity and consequent pull-out are simulated with a 3D finite element model of a human hemi-pelvis. The primary stability is assessed by determining the polar gap and the maximum pull-out force. The polar gap increases along with all considered parameters. The pull-out force shows a continuous increase with Ec and Et and a non-linear variation as a function of μ and IF is obtained. For μ > 0.6 and IF > 1.4 mm the primary stability decreases, and a combination of smaller μ and IF lead to a better fixation. Based on the patient's bone stiffness, optimal combinations of μ and IF can be identified. The results are in good qualitative agreement with previous studies and provide a better understanding of the determinants of the AC implant primary stability. They suggest a guideline for the optimal choice of implant surface roughness and IF based on the patient's bone quality.
Collapse
|
9
|
Yoshida K, Fukushima K, Sakai R, Uchiyama K, Takahira N, Ujihira M. Influence of outer geometry on primary stability for uncemented acetabular shells in developmental dysplasia of the hip. Proc Inst Mech Eng H 2020; 235:65-72. [PMID: 32996400 DOI: 10.1177/0954411920960000] [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: 11/17/2022]
Abstract
Excellent primary stability of uncemented acetabular shells is essential to obtain successful clinical outcomes. However, in the case of developmental dysplasia of the hip (DDH), aseptic loosening may be induced by instability due to a decrease of the contact area between the acetabular shell and host bone. The aim of this study was to assess the primary stability of two commercially-available acetabular shells, hemispherical and hemielliptical, in normal and DDH models. Synthetic bone was reamed using appropriate surgical reamers for each reaming condition (normal acetabular model). The normal acetabular model was also cut diagonally at 40° to create a dysplasia model. Stability of the acetabular components was evaluated by the lever-out test. In the normal acetabular model conditions, the maximum primary stabilities of hemispherical and hemielliptical shells were observed in the 1-mm under- and 1-mm over-reamed conditions, respectively, and the resulting stabilities were comparable. The lateral defect in the dysplasia model had an adverse effect on the primary stabilities of the two designs. The lever-out moment of the hemielliptical acetabular shell was 1.4 times greater than that of the hemispherical acetabular shell in the dysplasia model. The hemispherical shell is useful for the normal acetabular condition, and the hemielliptical shell for the severe dysplasia condition, in the context of primary stability.
Collapse
Affiliation(s)
- Kazuhiro Yoshida
- Department of Medical Engineering and Technology, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Kensuke Fukushima
- Department of Orthopaedic Surgery, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Rina Sakai
- Department of Medical Engineering and Technology, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Katsufumi Uchiyama
- Department of Orthopaedic Surgery, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Naonobu Takahira
- Department of Orthopaedic Surgery, Kitasato University, Sagamihara, Kanagawa, Japan.,Department of Rehabilitation, Kitasato University, Sagamihara, Kanagawa, Japan
| | - Masanobu Ujihira
- Department of Medical Engineering and Technology, Kitasato University, Sagamihara, Kanagawa, Japan
| |
Collapse
|
10
|
Comparison of Test Setups for the Experimental Evaluation of the Primary Fixation Stability of Acetabular Cups. MATERIALS 2020; 13:ma13183982. [PMID: 32916802 PMCID: PMC7559462 DOI: 10.3390/ma13183982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/28/2020] [Accepted: 09/03/2020] [Indexed: 11/22/2022]
Abstract
Sufficient primary fixation stability is the basis for the osseointegration of cementless acetabular cups. Several test methods have been established for determining the tilting moment of acetabular press-fit cups, which is a measure for their primary fixation stability. The central aim of this experimental study was to show the differences between the commonly used lever-out test method (Method 1) and the edge-load test method (Method 2) in which the cup insert is axially loaded (1 kN) during the tilting process with respect to the parameters, tilting moment, and interface stiffness. Therefore, using a biomechanical cup block model, a press-fit cup design with a macro-structured surface was pushed into three cavity types (intact, moderate superior defect, and two-point-pinching cavity) made of 15 pcf and 30 pcf polyurethane foam blocks (n = 3 per cavity and foam density combination), respectively. Subsequently, the acetabular cup was disassembled from the three artificial bone cavities using the lever-out and the edge-load test method. Tilting moments determined with Method 1 ranged from 2.72 ± 0.29 Nm to 49.08 ± 1.50 Nm, and with Method 2, they ranged from 41.40 ± 1.05 Nm to 112.86 ± 5.29 Nm. In Method 2, larger areas of abrasion were observed in the artificial bone cavity compared to Method 1. This indicates increased shear forces at the implant–bone interface in the former method. In conclusion, Method 1 simulates the technique used by orthopedic surgeons to assess the correct fit of the trial cup, while Method 2 simulates the tilting of the cup in the acetabular bone cavity under in situ loading with the hip resultant force.
Collapse
|
11
|
Deeper Central Reaming May Enhance Initial Acetabular Shell Fixation. Arthroplast Today 2020; 6:343-349. [PMID: 32548228 PMCID: PMC7286971 DOI: 10.1016/j.artd.2020.03.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 03/16/2020] [Accepted: 03/22/2020] [Indexed: 12/02/2022] Open
Abstract
Background The initial stability of press-fit acetabular components is partially determined by the reaming technique. Nonhemispherical (NHS) acetabular shells, which have a larger radius at the rim than the dome, often require larger reaming preparations than the same-sized hemispherical (HS) shells. Furthermore, deeper central reaming may provide a more stable press fit. Using a reproducible, in vitro protocol, we compared initial shell stability under different reaming techniques with HS and NHS acetabular components. Methods Cavities for 54-mm NHS and 56-mm HS acetabular components were premachined in 20-pcf Sawbones blocks. Acetabular cavities included diameters of 54, 55, “54+,” and “55+”. “+” indicates a cavity with a 2-mm smaller diameter that is 2-mm deeper. A 4750N statically applied force seated shells to a height that was comparable with shell height after an orthopaedic surgeon’s manual impaction. Force required to dislodge shells was assessed via a straight torque-out with a linear load. Results Increased preparation depth (+) was associated with deeper shell seating in all groups. Deeper central reaming increased required lever-out force for all groups. Overall, HS and NHS implants prepared with 55 + preparation had the highest lever-out forces, although this was not significantly higher than those with 54+. Conclusions In 20-pcf Sawbones, representing dense bone, overreaming depth by 1-mm improved initial seating measurements. In both HS and NHS acetabular shells, seating depth and required lever-out force were higher in the “+” category. It is unclear, however, whether a decreased diameter ream increased seating stability (55+ vs 54+). Clinically, this deeper central reaming technique may help initial acetabular stability.
Collapse
|
12
|
Goossens Q, Pastrav LC, Mulier M, Desmet W, Vander Sloten J, Denis K. Two Different Methods to Measure the Stability of Acetabular Implants: A Comparison Using Artificial Acetabular Models. SENSORS 2020; 20:s20010254. [PMID: 31906330 PMCID: PMC6983091 DOI: 10.3390/s20010254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 12/28/2019] [Accepted: 12/30/2019] [Indexed: 11/24/2022]
Abstract
The total number of total hip arthroplasties is increasing every year, and approximately 10% of these surgeries are revisions. New implant design and surgical techniques are evolving quickly and demand accurate preclinical evaluation. The initial stability of cementless implants is one of the main concerns of these preclinical evaluations. A broad range of initial stability test methods is currently used, which can be categorized into two main groups: Load-to-failure tests and relative micromotion measurements. Measuring relative micromotion between implant and bone is recognized as the golden standard for implant stability testing as this micromotion is directly linked to the long-term fixation of cementless implants. However, specific custom-made set-ups are required to measure this micromotion, with the result that numerous studies opt to perform more straightforward load-to-failure tests. A custom-made micromotion test set-up for artificial acetabular bone models was developed and used to compare load-to-failure (implant push-out test) with micromotion and to assess the influence of bone material properties and press-fit on the implant stability. The results showed a high degree of correlation between micromotion and load-to-failure stability metrics, which indicates that load-to-failure stability tests can be an appropriate estimator of the primary stability of acetabular implants. Nevertheless, micromotions still apply as the golden standard and are preferred when high accuracy is necessary. Higher bone density resulted in an increase in implant stability. An increase of press-fit from 0.7 mm to 1.2 mm did not significantly increase implant stability.
Collapse
Affiliation(s)
- Quentin Goossens
- Department of Mechanical Engineering, Campus Group T, KU Leuven, 3000 Leuven, Belgium
- Correspondence:
| | - Leonard Cezar Pastrav
- Department of Mechanical Engineering, Campus Group T, KU Leuven, 3000 Leuven, Belgium
| | - Michiel Mulier
- Department of Orthopedics, University Hospital Leuven, 3000 Leuven, Belgium
| | - Wim Desmet
- Department of Mechanical Engineering, PMA Division, KU Leuven, 3000 Leuven, Belgium
| | - Jos Vander Sloten
- Department of Mechanical Engineering, Biomechanics Section, KU Leuven, 3000 Leuven, Belgium
| | - Kathleen Denis
- Department of Mechanical Engineering, Campus Group T, KU Leuven, 3000 Leuven, Belgium
- Department of Mechanical Engineering, Biomechanics Section, KU Leuven, 3000 Leuven, Belgium
| |
Collapse
|
13
|
Laser Resonance Frequency Analysis: A Novel Measurement Approach to Evaluate Acetabular Cup Stability During Surgery. SENSORS 2019; 19:s19224876. [PMID: 31717400 PMCID: PMC6891423 DOI: 10.3390/s19224876] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/04/2019] [Accepted: 11/07/2019] [Indexed: 12/12/2022]
Abstract
Artificial joint acetabular cup stability is essential for successful total hip arthroplasty. However, a quantitative evaluation approach for clinical use is lacking. We developed a resonance frequency analysis (RFA) system involving a laser system that is fully contactless. This study aimed to investigate the usefulness of laser RFA for evaluating acetabular cup stability. First, the finite element method was performed to determine the vibration mode for analysis. Second, the acetabular cup was press-fitted into a reamed polyurethane cavity that replicated the human acetabular roof. The implanted acetabular cup was vibrated with pulse laser irradiation and the induced vibration was detected with a laser Doppler vibrometer. The time domain signal from the vibrometer was analyzed by fast Fourier transform to obtain the vibration frequency spectrum. After laser RFA, the pull-down force of the acetabular cup was measured as conventional implant fixation strength. The frequency of the first highest amplitude between 2 kHz and 6 kHz was considered as the resonance peak frequency, and its relationship with the pull-down force was assessed. The peak frequency could predict the pull-down force (R2 = 0.859, p < 0.000). Our findings suggest that laser RFA might be useful to measure acetabular cup stability during surgery.
Collapse
|
14
|
Raffa ML, Nguyen VH, Tabor E, Immel K, Housset V, Flouzat-Lachaniette CH, Haiat G. Dependence of the primary stability of cementless acetabular cup implants on the biomechanical environment. Proc Inst Mech Eng H 2019; 233:1237-1249. [DOI: 10.1177/0954411919879250] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Biomechanical phenomena occurring at the bone–implant interface during the press-fit insertion of acetabular cup implants are still poorly understood. This article presents a nonlinear geometrical two-dimensional axisymmetric finite element model aiming at describing the biomechanical behavior of the acetabular cup implant as a function of the bone Young’s modulus Eb, the diametric interference fit ( IF), and the friction coefficient µ. The numerical model was compared with experimental results obtained from an in vitro test, which allows to determine a reference configuration with the parameter set: μ* = 0.3, [Formula: see text], and IF* = 1 mm for which the maximal contact pressure tN = 10.7 MPa was found to be localized at the peri-equatorial rim of the acetabular cavity. Parametric studies were carried out, showing that an optimal value of the pull-out force can be defined as a function of μ, Eb, and IF. For the reference configuration, the optimal pull-out force is obtained for μ = 0.6 (respectively, Eb = 0.35 GPa and IF = 1.4 mm). For relatively low value of µ ( µ < 0.2), the optimal value of IF linearly increases as a function of µ independently of Eb, while for µ > 0.2, the optimal value of IF has a nonlinear dependence on µ and decreases as a function of Eb. The results can be used to help surgeons determine the optimal value of IF in a patient specific manner.
Collapse
Affiliation(s)
- Maria Letizia Raffa
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Créteil, France
| | - Vu-Hieu Nguyen
- Université Paris-Est, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Créteil, France
| | - Elisabeth Tabor
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Créteil, France
| | - Katharina Immel
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Créteil, France
- Aachen Institute for Advanced Study in Computational Engineering Science (AICES), RWTH Aachen University, Aachen, Germany
| | - Victor Housset
- Service de Chirurgie Orthopédique et Traumatologique du Centre Hospitalier Universitaire Henri Mondor, Créteil, France
- Équipe 10, Groupe 5, IMRB U955, INSERM/UPEC, Créteil, France
| | - Charles-Henri Flouzat-Lachaniette
- Service de Chirurgie Orthopédique et Traumatologique du Centre Hospitalier Universitaire Henri Mondor, Créteil, France
- Équipe 10, Groupe 5, IMRB U955, INSERM/UPEC, Créteil, France
| | - Guillaume Haiat
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, MSME UMR 8208 CNRS, Créteil, France
| |
Collapse
|
15
|
Gao X, Fraulob M, Haïat G. Biomechanical behaviours of the bone-implant interface: a review. J R Soc Interface 2019; 16:20190259. [PMID: 31362615 PMCID: PMC6685012 DOI: 10.1098/rsif.2019.0259] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/01/2019] [Indexed: 01/09/2023] Open
Abstract
In recent decades, cementless implants have been widely used in clinical practice to replace missing organs, to replace damaged or missing bone tissue or to restore joint functionality. However, there remain risks of failure which may have dramatic consequences. The success of an implant depends on its stability, which is determined by the biomechanical properties of the bone-implant interface (BII). The aim of this review article is to provide more insight on the current state of the art concerning the evolution of the biomechanical properties of the BII as a function of the implant's environment. The main characteristics of the BII and the determinants of implant stability are first introduced. Then, the different mechanical methods that have been employed to derive the macroscopic properties of the BII will be described. The experimental multi-modality approaches used to determine the microscopic biomechanical properties of periprosthetic newly formed bone tissue are also reviewed. Eventually, the influence of the implant's properties, in terms of both surface properties and biomaterials, is investigated. A better understanding of the phenomena occurring at the BII will lead to (i) medical devices that help surgeons to determine an implant's stability and (ii) an improvement in the quality of implants.
Collapse
Affiliation(s)
- Xing Gao
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
- Research Centre for Medical Robotics and Minimally Invasive Surgical Devices, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Manon Fraulob
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
| | - Guillaume Haïat
- CNRS, Laboratoire Modélisation et Simulation Multi Echelle, UMR CNRS 8208, 61 avenue du Général de Gaulle, 94010 Créteil cedex, France
| |
Collapse
|
16
|
Wiznia DH, Schwarzkopf R, Iorio R, Long WJ. Factors That Influence Bone-Ingrowth Fixation of Press-Fit Acetabular Cups. JBJS Rev 2019; 7:e2. [DOI: 10.2106/jbjs.rvw.18.00147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
|
17
|
Weißmann V, Ramskogler T, Schulze C, Bader R, Hansmann H. Influence of Synthetic Bone Substitutes on the Anchorage Behavior of Open-Porous Acetabular Cup. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E1052. [PMID: 30935040 PMCID: PMC6479851 DOI: 10.3390/ma12071052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 03/25/2019] [Accepted: 03/26/2019] [Indexed: 11/17/2022]
Abstract
BACKGROUND The development in implants such as acetabular cups using additive manufacturing techniques is playing an increasingly important role in the healthcare industry. METHOD This study compared the primary stability of four selectively laser-melted press-fit cups (Ti6Al4V) with open-porous, load-bearing structural elements on the surface. The aim was to assess whether the material of the artificial bone stock affects the primary stability of the acetabular cup. The surface structures consist of repeated open-porous, load-bearing elements orthogonal to the acetabular surface. Experimental pull-out and lever-out tests were performed on exact-fit and press-fit cups to evaluate the primary stability of the cups in different synthetic bone substitutes. The acetabular components were placed in three different commercially available synthetic materials (ROHACELL-IGF 110, SikaBlock M330, Sawbones Solid Rigid). Results & conclusions: Within the scope of the study, it was possible to show the differences in fixation strength between the tested acetabular cups depending on their design, the structural elements used, and the different bone substitute material. In addition, functional correlations could be found which provide a qualitative reference to the material density of the bone stock and the press-fit volume of the acetabular cups.
Collapse
Affiliation(s)
- Volker Weißmann
- Faculty of Engineering, University of Applied Sciences, Technology, Business and Design, Philipp-Müller-Str. 14, 23966 Wismar, Germany.
- Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medicial Center, Doberaner Strasse 142, 18057 Rostock, Germany.
| | - Tim Ramskogler
- Department Industrial Engineering, Technical University of Applied Sciences, Hetzenrichter Weg 15, 92637 Weiden, Germany.
| | - Christian Schulze
- Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medicial Center, Doberaner Strasse 142, 18057 Rostock, Germany.
| | - Rainer Bader
- Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medicial Center, Doberaner Strasse 142, 18057 Rostock, Germany.
| | - Harald Hansmann
- Faculty of Engineering, University of Applied Sciences, Technology, Business and Design, Philipp-Müller-Str. 14, 23966 Wismar, Germany.
| |
Collapse
|
18
|
Experimental Characterization of the Primary Stability of Acetabular Press-Fit Cups with Open-Porous Load-Bearing Structures on the Surface Layer. METALS 2018. [DOI: 10.3390/met8100839] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background: Nowadays, hip cups are being used in a wide range of design versions and in an increasing number of units. Their development is progressing steadily. In contrast to conventional methods of manufacturing acetabular cups, additive methods play an increasingly central role in the development progress. Method: A series of eight modified cups were developed on the basis of a standard press-fit cup with a pole flattening and in a reduced version. The surface structures consist of repetitive open-pore load-bearing textural elements aligned right-angled to the cup surface. We used three different types of unit cells (twisted, combined and combined open structures) for constructing of the surface structure. All cups were manufactured using selective laser melting (SLM) of titanium powder (Ti6Al4V). To evaluate the primary stability of the press fit cups in the artificial bone cavity, pull-out and lever-out tests were conducted. All tests were carried out under exact fit conditions. The closed-cell polyurethane (PU) foam, which was used as an artificial bone cavity, was characterized mechanically in order to preempt any potential impact on the test results. Results and conclusions: The pull-out forces as well as the lever moments of the examined cups differ significantly depending on the elementary cells used. The best results in pull-out forces and lever-out moments are shown by the press-fit cups with a combined structure. The results for the assessment of primary stability are related to the geometry used (unit cell), the dimensions of the unit cell, and the volume and porosity responsible for the press fit. Corresponding functional relationships could be identified. The findings show that the implementation of reduced cups in a press-fit design makes sense as part of the development work.
Collapse
|
19
|
Weißmann V, Boss C, Bader R, Hansmann H. A novel approach to determine primary stability of acetabular press-fit cups. J Mech Behav Biomed Mater 2018; 80:1-10. [PMID: 29414463 DOI: 10.1016/j.jmbbm.2018.01.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 11/11/2017] [Accepted: 01/16/2018] [Indexed: 11/28/2022]
Abstract
Today hip cups are used in a large variety of design variants and in increasing numbers of units. Their development is steadily progressing. In addition to conventional manufacturing methods for hip cups, additive methods, in particular, play an increasingly important role as development progresses. The present paper describes a modified cup model developed based on a commercially available press-fit cup (Allofit 54/JJ). The press-fit cup was designed in two variants and manufactured using selective laser melting (SLM). Variant 1 (Ti) was modeled on the Allofit cup using an adapted process technology. Variant 2 (Ti-S) was provided with a porous load bearing structure on its surface. In addition to the typical (complete) geometry, both variants were also manufactured and tested in a reduced shape where only the press-fit area was formed. To assess the primary stability of the press-fit cups in the artificial bone cavity, pull-out and lever-out tests were carried out. Exact fit conditions and two-millimeter press-fit were investigated. The closed-cell PU foam used as an artificial bone cavity was mechanically characterized to exclude any influence on the results of the investigation. The pull-out forces of the Ti-variant (complete-526 N, reduced-468 N) and the Ti-S variant (complete-548 N, reduced-526 N) as well as the lever-out moments of the Ti-variant (complete-10 Nm, reduced-9.8 Nm) and the Ti-S variant (complete-9 Nm, reduced-7.9 N) show no significant differences in the results between complete and reduced cups. The results show that the use of reduced cups in a press-fit design is possible within the scope of development work.
Collapse
Affiliation(s)
- Volker Weißmann
- Faculty of Engineering, University of Applied Science, Technology, Business and Design, Philipp-Müller-Str. 14, 23966 Wismar, Germany; Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medicine, Doberaner Strasse 142, Rostock 18057, Germany.
| | - Christian Boss
- Institute for Polymer Technologies e.V., Alter Holzhafen 19, 23966 Wismar, Germany.
| | - Rainer Bader
- Biomechanics and Implant Technology Research Laboratory, Department of Orthopedics, Rostock University Medicine, Doberaner Strasse 142, Rostock 18057, Germany.
| | - Harald Hansmann
- Faculty of Engineering, University of Applied Science, Technology, Business and Design, Philipp-Müller-Str. 14, 23966 Wismar, Germany.
| |
Collapse
|
20
|
Impact Force, Polar Gap and Modal Parameters Predict Acetabular Cup Fixation: A Study on a Composite Bone. Ann Biomed Eng 2018; 46:590-604. [DOI: 10.1007/s10439-018-1980-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 01/06/2018] [Indexed: 10/18/2022]
|
21
|
Small SR, Meding JB, Oja JW, Lakstins KS, Gehron DJ, Rogge RD, Buckley CA. Shell design and reaming technique affect deformation in mobile-bearing total hip arthroplasty acetabular components. Proc Inst Mech Eng H 2017; 231:691-698. [DOI: 10.1177/0954411917701952] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Press-fit acetabular components are susceptible to rim deformation. The inherent variability within acetabular reaming techniques may generate increased press-fit and, subsequently, additional component deformation. The purpose of this study was to analyze the insertion and deformation characteristics of acetabular components designed for dual-mobility systems based on component design, size, and reaming technique. Shell deformation was quantified in a validated worst-case scenario foam pinch model. Thin-walled, one-piece, and modular dual-mobility shells of varying size were implanted in under- and over-reamed cavities with insertion force measured and shell deformation assessed using digital image correlation. Increased shell size resulted in larger rim deformation in one-piece components, with a reduction in press-fit by 1 mm resulting in up to 48% reduction in insertion forces and between 23% and 51% reduction in shell deformation. Lower insertion forces and deformations were observed in modular components. Variability in acetabular reaming plays a significant role in the ease of implantation and component deformation in total hip arthroplasty. Modular components are less susceptible to deformation than thin-walled monoblock shells. Care should be taken to avoid excessive under-reaming, particularly in the scenario of large shell size and high-density patient bone stock.
Collapse
Affiliation(s)
| | | | - Jordan W Oja
- Department of Biology & Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, IN, USA
| | - Katherine S Lakstins
- Department of Biology & Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, IN, USA
| | - Danielle J Gehron
- Department of Biology & Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, IN, USA
| | - Renee D Rogge
- Department of Biology & Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, IN, USA
| | - Christine A Buckley
- Department of Biology & Biomedical Engineering, Rose-Hulman Institute of Technology, Terre Haute, IN, USA
| |
Collapse
|
22
|
Segmental acetabular rim defects, bone loss, oversizing, and press fit cup in total hip arthroplasty evaluated with a probabilistic finite element analysis. INTERNATIONAL ORTHOPAEDICS 2016; 41:1527-1533. [PMID: 28012048 DOI: 10.1007/s00264-016-3369-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 12/02/2016] [Indexed: 01/21/2023]
Abstract
PURPOSE Management of segmental rim defects and bone mineral density (BMD) loss in the elderly prior to total hip replacement is unclear within classification systems for acetabular bone loss. In this study, our objectives were (1) to understand how a reduction in BMD in the elderly affects the oversizing of a press-fit cup for primary fixation and (2) to evaluate whether the location of the segmental defect affected cup fixation. METHODS A finite element (FE) model was used to simulate and evaluate cup insertion and fixation in the context of segmental rim defects. We focused on the distribution of patients over age 70 and used BMD (estimated from CT) as a proxy for aging's implications on THR and used probabilistic FE analysis to understand how BMD loss affects oversizing of a press-fit cup. RESULTS A cup oversized by 1.10 ± 0.28 mm provides sufficient fixation and lower stresses at the cup-bone interface for elderly patients. Defects in the anterior column and posterior column both required the same mean insertion force for cup seating of 84% (taken as an average of 2 anterior column and 2 posterior column defects) compared to the control configuration, which was 5% greater than the insertion force for a superior rim defect and 12% greater than the insertion force for an inferior rim defect. CONCLUSIONS A defect along the superior or inferior rim had a minimal effect on cup fixation, while a defect in the columns created cup instability and increased stress at the defect location.
Collapse
|
23
|
Primary cup stability in THA with augmentation of acetabular defect. A comparison of healthy and osteoporotic bone. Orthop Traumatol Surg Res 2015; 101:667-73. [PMID: 26300456 DOI: 10.1016/j.otsr.2015.07.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 07/01/2015] [Accepted: 07/07/2015] [Indexed: 02/02/2023]
Abstract
BACKGROUND CONTEXT Reconstruction of acetabular defect has been advocated as standard procedure in total hip arthroplasty. The presence of bony defects at the acetabulum is viewed as a cause of instability and acetabular wall augmentation is often used without proper consideration of surrounding bone density. The initial cup-bone stability is, however, a challenge and a number of studies supported by clinical follow-ups of patients suggested that if the structural graft needs supporting more than 50% of the acetabular component, a reconstruction cage device spanning ilium to ischium should be preferred to protect the graft and provide structural stability. This study aims to (1) investigate the relationship between cup motion and bone density and (2) quantify the re-distribution of stress at the defect site after augmentation. HYPHOTESIS Paprosky type I or II, acetabular defects, when reconstructed with bone screws supported by bioabsorbable calcified triglyceride bone cement are significantly less effective for osteoporotic bone than healthy bone. MATERIALS AND METHODS Acetabular wall defects were reconstructed on six cadaveric subjects with bioabsorbable calcified triglyceride bone cement using a re-bar technique. Data of the specimen with higher bone density was used to validate a Finite Element Model. Values of bone apparent density ranging from healthy to osteoporotic were simulated to evaluate (1) the cup motion, through both displacement and rotation, (2) and the von Mises stress distribution. RESULTS Defect reconstruction with bone screws and bioabsorbable calcified triglyceride bone cement results in a re-distribution of stress at the defect site. For a reduction of 65% in bone density, the cup displacement was similar to a healthy bone for loads not exceeding 300 N, as load progressed up to 1500 N, the reconstructed defect showed increase of 99 μm (128%) in displacement and of 0.08° in rotation angle. CONCLUSIONS Based on the results, we suggest that an alternative solution to wall defect augmentation with bone screws supported by bioabsorbable calcified triglyceride bone cement, be used for osteoporotic bone. LEVEL OF EVIDENCE Level IV, experimental and cadaveric study.
Collapse
|