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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.
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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
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Tsukushi S, Nishida Y, Hirose T, Nakata E, Nakagawa R, Nakamura T, Imanishi J, Nagano A, Tamiya H, Ueda T. Short-term clinical outcomes of Kyocera Modular Limb Salvage System designed cementless stems for the endoprosthetic reconstruction of lower extremities: a Japanese Musculoskeletal Oncology Group multi-institutional study. BMC Cancer 2022; 22:781. [PMID: 35842696 PMCID: PMC9288729 DOI: 10.1186/s12885-022-09873-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 07/06/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The high rate of aseptic loosening of cemented stems has led to their frequent use in endoprosthetic reconstruction. However, problems, such as stem breakage and stress shielding at the insertion site, remain. The Japanese Musculoskeletal Oncology Group (JMOG) has developed Kyocera Modular Limb Salvage System (KMLS) cementless stems with a unique tapered press-fit and short fixation design. This study aimed to clarify the short-term postoperative outcomes of this prosthesis and validate the stem design. METHODS One hundred cases of KMLS cementless stems (51 male patients; median age, 49 years; mean follow-up period, 35 months), with a minimum follow-up of 2 years, for the proximal femur (PF), distal femur (DF), and proximal tibia were prospectively registered for use. Prosthesis survival, complication rates, postoperative functional, and radiographical evaluation were analyzed. Complications or failures after insertion of the KMLS endoprostheses were classified into five types and functional results were analyzed according to the MSTS scoring system at postoperative 1 year. The diaphyseal interface and anchorage were graded by the ISOLS system at postoperative 2 years. RESULTS The overall prosthesis survival rates at 2 and 4 years were 88.2 and 79.6%, respectively. The prosthesis-specific survival rate excluding infection and tumor recurrence was 90.2 and 87.9%, respectively. Younger age (p = 0.045) and primary tumor (p = 0.057) were associated with poor prognosis of prosthesis-specific survival excluding infection and tumor recurrence. Complications were observed in 31 patients, 13 patients underwent revision surgery. The mean MSTS functional score at 1 year postoperatively was 68%. Early implant loosening was significantly more common in the DF (p = 0.006) and PF/DF straight stem (p = 0.038). The ISOLS radiographic evaluation at 2 years after surgery revealed good bone remodeling and anchorage in most cases (bone remodeling: 90% / excellent and good, anchorage: 97% / excellent and good). CONCLUSIONS Tumor endoprosthesis long-term fixation to the diaphysis of the lower extremity remains challenging. The KMLS cementless stem with a unique tapered press fit design showed good short-term results in maintaining bone stock. To prevent early loosening, a curved stem should be used in PF and DF, but long-term follow-up is necessary.
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Affiliation(s)
- Satoshi Tsukushi
- Department of Orthopaedic Surgery, Aichi Cancer Center Hospital, 1-1 Kanokoden, Chikusa-ku Nagoya, 464-8681, Japan.
| | - Yoshihiro Nishida
- Department of Rehabilitation Medicine, Nagoya University Hospital, Nagoya, Japan
| | - Takeshi Hirose
- Department of Musculoskeletal Oncology, National Cancer Center Hospital, Tokyo, Japan
| | - Eiji Nakata
- Department of Orthopaedic Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan
| | - Rumi Nakagawa
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, Japan
| | - Tomoki Nakamura
- Department of Orthopedic Surgery, Mie University Graduate School of Medicine, Tsu, Japan
| | - Jungo Imanishi
- Department of Orthopaedic Oncology and Surgery, Saitama Medical University International Medical Center, Hidaka, Japan
| | - Akihito Nagano
- Department of Orthopaedic Surgery, Gifu University School of Medicine, Gifu, Japan
| | - Hironari Tamiya
- Department of Orthopedic Surgery, Osaka International Cancer Institute, Osaka, Japan
| | - Takafumi Ueda
- Department of Orthopaedic Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan
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Causey GC, Picha GJ, Price J, Pelletier MH, Wang T, Walsh WR. In-Vivo response to a novel pillared surface morphology for osseointegration in an ovine model. J Mech Behav Biomed Mater 2021; 119:104462. [PMID: 33839536 DOI: 10.1016/j.jmbbm.2021.104462] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 03/10/2021] [Accepted: 03/11/2021] [Indexed: 11/16/2022]
Abstract
Primary stability and secondary fixation of orthopedic implants to bony tissues are important for healing and long-term functionality. Load sharing and stress transfer are key requirements of an effective implant/tissue interface. This paper presents a novel, macro-scale osseointegration surface morphology which addresses the implant/tissue interface from both the biologic as well as biomechanical perspective. The surface morphology is a controlled, engineered, open topography manifested as discrete pillars projecting from the implant enabling continuous bone ingrowth. The pillared surface is distinct from other porous surfaces and can be differentiated by the localization of the implant material into discrete pillars enabling a continuous mass of bone to freely and easily interdigitate into the pillared structure. Traditional porous structures distribute the implant material throughout the surface forcing the bone to grow in a discontinuous manner. Creating an open and continuous space or "open porosity" in and around the pillar structure allows the bone to easily interdigitate with the implant surface without encumberment from a continuous porous structure. An in-vivo study, using an established ovine model, was undertaken examining the effects of pillar morphology on bone ingrowth and mechanical performance. Cortical and cancellous sites were evaluated utilizing histology, histomophometry, and mechanical pushout, at 4 and 12 weeks. Robust bone ingrowth occurred for all morphologies as was noted in review of the study results. An increase in volume and maturity of bone was noted between the intermediated and final time points. Histomophometry demonstrated over 40% and 80% new bone occupied the available "ingrowth" area at 12 weeks for cancellous and cortical sites (respectively). Histologic review showed little fibrous tissue ingrowth at the interface with no adverse cellular reactions. Testing of cortical samples demonstrated a significant increase in pushout load between the 4 and 12 week timepoints and a 4-8 fold increase in pushout load as compared to the grit blast control. These results demonstrated the effectiveness of the novel interface for orthopedic applications in an in-vivo ovine model.
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Affiliation(s)
| | | | - Jamey Price
- Applied Medical Technology, Brecksville, OH, USA
| | | | - Tian Wang
- The University of New South Wales, Australia
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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.
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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
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Bone ongrowth of a cementless silver oxide-containing hydroxyapatite-coated antibacterial acetabular socket. J Orthop Sci 2019; 24:658-662. [PMID: 30718042 DOI: 10.1016/j.jos.2018.12.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/05/2018] [Accepted: 12/20/2018] [Indexed: 02/09/2023]
Abstract
BACKGROUND The silver oxide-containing hydroxyapatite-coated socket (KYOCERA, Osaka, Japan) is a cementless antibacterial implant that has both the osteoconductivity of the HA and the antibacterial activity of silver. The silver oxide-containing hydroxyapatite coating was shown to have good osteoconductivity and new bone formation in vitro and in vivo. However, the histological bone ongrowth of this implant has not been proven in a clinical study. METHODS We analyzed bone ongrowth using two silver oxide-containing hydroxyapatite-coated sockets that were removed in revision total hip arthroplasty for recurrent dislocation. A histomorphometric analysis was performed using a scanning electron microscope (SEM) connected to a CCD camera and an elemental analysis was performed by energy-dispersive elemental spectrometry (EDS). RESULT A white structure thought to be osseous tissue was attached to the retrieved socket surface macroscopically, and histological bone ongrowth of the silver oxide-containing hydroxyapatite coating of the socket was confirmed by SEM. In addition, the presence of silver in the silver oxide-containing hydroxyapatite coating was confirmed in an elemental analysis by EDS. CONCLUSION Histologically, the silver oxide-containing hydroxyapatite-coated socket presented bone ongrowth in this clinical study.
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Yoshimoto K, Nakashima Y, Wakiyama M, Hara D, Nakamura A, Iwamoto M. Initial stability of a highly porous titanium cup in an acetabular bone defect model. J Orthop Sci 2018; 23:665-670. [PMID: 29657105 DOI: 10.1016/j.jos.2018.03.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 03/15/2018] [Accepted: 03/25/2018] [Indexed: 11/27/2022]
Abstract
BACKGROUNDS The purpose of this study was to quantify the initial stability of a highly porous titanium cup using an acetabular bone defect model. METHODS The maximum torque of a highly porous titanium cup, with a pore size of 640 μm and porosity of 60%, was measured using rotational and lever-out torque testing and compared to that of a titanium-sprayed cup. The bone models were prepared using a polyurethane foam block and had three levels of bone coverage: 100, 70, and 50%. RESULTS The highly porous titanium cup demonstrated significantly higher maximum torque than the titanium-sprayed cups in the three levels of bone defects. On rotational torque testing, it was found to be 1.5, 1.3, and 1.3 times stronger than the titanium-sprayed cups with 100, 70 and 50% bone coverage, respectively. Furthermore, it was found to be 2.2, 2.3, and 1.5 times stronger on lever-out testing than the titanium-sprayed cup. No breakage in the porous layers was noted during the testing. CONCLUSION This study provides additional evidence of the initial stability of highly porous titanium cup, even in the presence of acetabular bone defects.
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Affiliation(s)
- Kensei Yoshimoto
- Department of Orthopedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
| | - Yasuharu Nakashima
- Department of Orthopedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
| | - Miyo Wakiyama
- Kyocera Medical Corporation, 3-3-31 Miyahara, Yodogawa-ku, Osaka, Osaka, 532-0003, Japan.
| | - Daisuke Hara
- Department of Orthopedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
| | - Akihiro Nakamura
- Kyocera Medical Corporation, 3-3-31 Miyahara, Yodogawa-ku, Osaka, Osaka, 532-0003, Japan.
| | - Mikio Iwamoto
- Kyocera Medical Corporation, 3-3-31 Miyahara, Yodogawa-ku, Osaka, Osaka, 532-0003, Japan.
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Preoperative Canal Bone Ratio is Related to High-Degree Stress Shielding: A Minimum 5-Year Follow-Up Study of a Proximally Hydroxyapatite-Coated Straight Tapered Titanium Femoral Component. J Arthroplasty 2018; 33:1764-1769. [PMID: 29366730 DOI: 10.1016/j.arth.2017.12.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 12/04/2017] [Accepted: 12/20/2017] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Few studies have reported risk factors for stress shielding. We sought to evaluate clinical and radiographic outcomes of a proximally hydroxyapatite-coated straight tapered titanium femoral component stem during a minimum 5-year follow-up and identify factors associated with high-degree stress shielding. METHODS A total of 156 total hip arthroplasties (n = 124; 98 women and 26 men; mean age, 56.5 years) with a minimum follow-up period of 5 years were included in the study. Clinical and radiologic measurements at follow-up (range, 5-16.3 years; mean, 10.2 years) were analyzed. RESULTS The mean preoperative Harris Hip Score (HHS) was 56.6, and the mean HHS at the latest follow-up was considerably improved at 86.8. Stress shielding at the latest follow-up was low degree in 136 (87%) hips and high degree in 20 (13%) hips. On average, high-degree stress shielding occurred 9.9 years (5-14 years) after surgery. The results of Cox proportional hazard analysis showed that a canal bone ratio ≥ 0.49 was an independent risk factor for high-degree stress shielding (P = .0075; hazard ratio, 3.981). HHS at the latest follow-up was significantly lower in high-degree stress shielding than in low-degree stress shielding (80.7 and 87.7, respectively; P = .0030). CONCLUSION Preoperative canal bone ratio ≥ 0.49 is independently associated with high-degree stress shielding. In addition, the number of cases with high-degree stress shielding significantly increased over time during a mean 10-year follow-up.
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Wear of XLPE liner against zirconium heads in cementless total hip arthroplasty for patients under 40 years of age. Hip Int 2017; 27:532-536. [PMID: 28574118 DOI: 10.5301/hipint.5000513] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/04/2017] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Total hip arthroplasty (THA) in the young is challenging. The purpose of this study was to retrospectively determine the clinical, radiographic, and polyethylene wear rate of relatively young patients. METHODS We evaluated the outcome of consecutive patients receiving primary THA who were under 40 years of age with a minimum 10-year follow-up. Indications for THA in these patients were osteoarthritis due to developmental dysplasia of the hip joint (9 hips), osteonecrosis of the femoral head (7 hips), juvenile idiopathic arthritis (2 hips), and osteoarthritis due to Perthes disease (1 hip). All THA were performed with a cross-linked ultra-high-molecular-weight polyethylene (XLPE) liner against zirconium heads with cementless implants. RESULTS The average Japanese Orthopaedic Association hip score significantly improved from 42 to 93 points at the latest follow-up. The mean steady wear was 0.015 mm/year (maximum 0.033 mm/year), and the mean creep wear was 0.111 mm (maximum 0.4 mm). Osteolysis was observed around 1 acetabular component and 2 stems. 1 femoral component had subsidence over 5 mm. All of the femoral components achieved fixation with an optimal interface with spot welds at the latest follow-up. Stress shielding was observed in all hips. CONCLUSIONS THA using an XLPE liner against zirconium heads appeared to have improved THA longevity. However, the imaging findings in some cases were suggestive of wear debris. A rigorous continual follow-up is required for relatively young patients undergoing THA.
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Minimum Lateral Bone Coverage Required for Securing Fixation of Cementless Acetabular Components in Hip Dysplasia. BIOMED RESEARCH INTERNATIONAL 2017; 2017:4937151. [PMID: 28299327 PMCID: PMC5337307 DOI: 10.1155/2017/4937151] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 01/26/2017] [Indexed: 11/23/2022]
Abstract
Objectives. To determine the minimum lateral bone coverage required for securing stable fixation of the porous-coated acetabular components (cups) in hip dysplasia. Methods. In total, 215 primary total hip arthroplasties in 199 patients were reviewed. The average follow-up period was 49 months (range: 24–77 months). The lateral bone coverage of the cups was assessed by determining the cup center-edge (cup-CE) angle and the bone coverage index (BCI) from anteroposterior pelvic radiographs. Further, cup fixation was determined using the modified DeLee and Charnley classification system. Results. All cups were judged to show stable fixation by bone ingrowth. The cup-CE angle was less than 0° in 7 hips (3.3%) and the minimum cup-CE angle was −9.2° (BCI: 48.8%). Thin radiolucent lines were observed in 5 hips (2.3%), which were not associated with decreased lateral bone coverage. Loosening, osteolysis, dislocation, or revision was not observed in any of the cases during the follow-up period. Conclusion. A cup-CE angle greater than −10° (BCI > 50%) was acceptable for stable bony fixation of the cup. Considering possible errors in manual implantation, we recommend that the cup position be planned such that the cup-CE angle is greater than 0° (BCI > 60%).
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Silver-Containing Hydroxyapatite Coating Reduces Biofilm Formation by Methicillin-Resistant Staphylococcus aureus In Vitro and In Vivo. BIOMED RESEARCH INTERNATIONAL 2016; 2016:8070597. [PMID: 28105433 PMCID: PMC5220461 DOI: 10.1155/2016/8070597] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 12/01/2016] [Accepted: 12/07/2016] [Indexed: 11/17/2022]
Abstract
Biofilm-producing bacteria are the principal causes of infections associated with orthopaedic implants. We previously reported that silver-containing hydroxyapatite (Ag-HA) coatings exhibit high antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). In the present study, we evaluated the effects of Ag-HA coating of implant surfaces on biofilm formation. Titanium disks (14-mm diameter, 1-mm thickness), one surface of which was coated with HA or 0.5%-3.0% Ag-HA with a thermal spraying technique, were used. In vitro, the disks were inoculated with an MRSA suspension containing 4 × 105 CFU and incubated for 1-2 weeks. In vivo, MRSA-inoculated HA and 3% Ag-HA disks (8.8-10.0 × 108 CFU) were implanted subcutaneously on the back of rats for 1-7 days. All disks were subsequently stained with a biofilm dye and observed under a fluorescence microscope, and biofilm coverage rates (BCRs) were calculated. The BCRs on the Ag-HA coating were significantly lower than those on the HA coating at all time points in vitro (p < 0.05). Similar results were observed in vivo (p < 0.001) without argyria. Ag-HA coating reduced biofilm formation by MRSA in vitro and in vivo; therefore, Ag-HA coating might be effective for reducing implant-associated infections.
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Abstract
INTRODUCTION Total hip replacement is a successful procedure with long survival records compared to other joint arthroplasties. Cemented implants have been available for many years, however the complications associated with loosening and, ultimately, failure over time has led to the development of cementless stems and implants.The ideal prosthesis should recreate a biomechanically normal hip joint, allow pain-free function and last the patient's life span without requiring revision. Optimal results with uncemented femoral stems rely on obtaining initial stability, osseointegration, biological fixation, and uniform stress transfer to the proximal bone.There are a multitude of factors that can affect the integration, stability and fixation of these stems into bone, and understanding these factors is the key to choosing the appropriate implant for a specific femur. METHODS This article aims to discuss cementless prostheses based on evidence-based practice. Geometry, roughness, stem coating, technique and bone quality are among the factors discussed. This was achieved through a review of the current literature. CONCLUSIONS Uncemented femoral stems have shown good, long-term survivorship and functional outcome, with promising results in younger patients.Limitations in the current literature make it difficult to assess and compare different designs to determine optimal indications for each type.Biological fixation, in which the prosthesis is directly fixed to the bone, is the preferred fixation method.Future studies of cementless implants should consistently address patient age, activity level, bone type, and deformities so that more definitive conclusions can be drawn about when to use each design.
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Sato T, Nakashima Y, Komiyama K, Yamamoto T, Motomura G, Iwamoto Y. The Absence of Hydroxyapatite Coating on Cementless Acetabular Components Does Not Affect Long-Term Survivorship in Total Hip Arthroplasty. J Arthroplasty 2016; 31:1228-1232. [PMID: 26730449 DOI: 10.1016/j.arth.2015.11.034] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Revised: 11/20/2015] [Accepted: 11/23/2015] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Hydroxyapatite (HA) has been applied to joint prostheses as a bioactive coating to prolong their durability. However, HA benefits for cup survival in total hip arthroplasty (THA) remain controversial. In this study, we compared the survival of cups with and without HA coating during a minimum follow-up of 18 years. METHODS In total, 183 THA cases in 163 patients were analyzed, including 73 cups with HA coating (HA(+) group) and 110 without HA coating (HA(-) group); otherwise, the cups had identical titanium-sprayed rough surfaces and were fixed with screws. In both groups, the same conventional polyethylene liners were applied. Zirconia and alumina ceramic heads were used in the HA(+) and HA(-) groups, respectively. We retrospectively analyzed cup survival based on cup revision for any reason or aseptic loosening as end points. RESULTS In total, 7 and 8 revisions were performed in the HA(-) and HA(+) groups with survival rates of 86.3% and 90.1%, respectively. Among them, 3 cups in the HA(-) group and 1 cup in the HA(+) group were revised for aseptic loosening in 20 years (survival rates 94.1% and 98.7%, respectively). No significant difference was detected in cup survival rates between the groups based on both end points. There were no stem revisions during the observation period. CONCLUSION The results suggested that HA coating did not have either beneficial or adverse effects on the long-term cup survival in primary cementless THA.
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Affiliation(s)
- Taishi Sato
- Department of Orthopaedic Surgery, Kyushu University, Fukuoka City, Fukuoka, Japan
| | - Yasuharu Nakashima
- Department of Orthopaedic Surgery, Kyushu University, Fukuoka City, Fukuoka, Japan
| | - Keisuke Komiyama
- Department of Orthopaedic Surgery, Kyushu University, Fukuoka City, Fukuoka, Japan
| | - Takuaki Yamamoto
- Department of Orthopaedic Surgery, Kyushu University, Fukuoka City, Fukuoka, Japan
| | - Goro Motomura
- Department of Orthopaedic Surgery, Kyushu University, Fukuoka City, Fukuoka, Japan
| | - Yukihide Iwamoto
- Department of Orthopaedic Surgery, Kyushu University, Fukuoka City, Fukuoka, Japan
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Kanazawa M, Nakashima Y, Hamai S, Hirata M, Iwamoto Y. Is a Stem Version on the Crosstable Lateral Radiograph Accurate in Total Hip Arthroplasty? J Arthroplasty 2016; 31:1356-1360. [PMID: 26763896 DOI: 10.1016/j.arth.2015.12.022] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 11/07/2015] [Accepted: 12/01/2015] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND In contrast to the acetabular cup version (CV), stem version (SV) measurement on the crosstable lateral radiograph has not been validated. We, therefore, investigated: (1) the difference of SV on the crosstable lateral radiograph from that measured using computed tomography data and (2) the reliability of SV measurement on the crosstable lateral radiograph. METHODS We examined the correlations of the crosstable-CV and crosstable-SV with true-CV (operative cup anteversion) and true-SV (neck version relative to the posterior condylar line) obtained using computed tomography data from 103 patients. We also produced the digital reconstructed crosstable lateral radiograph with adjusted hip flexion and rotation and defined SV on this image as the true-crosstable SV. RESULTS Significant positive correlations were noted between the crosstable-CV and true-CV, with a correlation coefficient of 0.79. In contrast, the correlation between the crosstable-SV and true-SV was very low (r = 0.30), with significantly higher deviation from the true-SV values when compared with the crosstable-CV (standard deviation, 11.6° vs 6.5°, P < .001). The true-crosstable SV was correlated with true-SV (r = 0.81); however, the average difference was 23.5° ± 8.9°. CONCLUSION Crosstable-SV differed from true-SV in the measurement plane and did not correlate well with the true-SV, suggesting the unreliability of its measurements. Therefore, the crosstable-SV is not recommended for clinical use.
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Affiliation(s)
- Masayuki Kanazawa
- Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Yasuharu Nakashima
- Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Satoshi Hamai
- Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Masanobu Hirata
- Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Yukihide Iwamoto
- Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
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Bone bonding strength of diamond-structured porous titanium-alloy implants manufactured using the electron beam-melting technique. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 59:1047-1052. [DOI: 10.1016/j.msec.2015.11.025] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Revised: 10/23/2015] [Accepted: 11/09/2015] [Indexed: 01/10/2023]
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Miyatake K, Jinno T, Koga D, Yamauchi Y, Muneta T, Okawa A. Comparison of Different Materials and Proximal Coatings Used for Femoral Components in One-Stage Bilateral Total Hip Arthroplasty. J Arthroplasty 2015; 30:2237-41. [PMID: 26190568 DOI: 10.1016/j.arth.2015.06.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 05/15/2015] [Accepted: 06/10/2015] [Indexed: 02/01/2023] Open
Abstract
To evaluate the mid-term effects of different materials and coatings used for femoral components, we prospectively performed 21 one-stage bilateral total hip arthroplasties using 2 anatomical stems which have identical geometries, randomized to side. One stem was made of Ti6Al4V alloy and had a hydroxyapatite coating on grit-blasted surface proximally, and the other was made of TMZF™ alloy and had a proximal coating of hydroxyapatite in addition to an arc-deposited titanium surface coating. Although we found extensions of radiopaque lines to the surface of coatings of seven grit-blasted stems whereas we found none in the case of the arc-deposited titanium stems, all hips showed excellent clinical and radiological outcomes as shown by radiographs and bone mineral density at the final follow-up, average 5.5 years postoperatively.
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Affiliation(s)
- Kazumasa Miyatake
- Department of Orthopaedic Surgery, Medical Hospital, Tokyo Medical and Dental University, Tokyo, Japan
| | - Tetsuya Jinno
- Department of Orthopaedic Surgery, Medical Hospital, Tokyo Medical and Dental University, Tokyo, Japan
| | - Daisuke Koga
- Department of Orthopaedic Surgery, Medical Hospital, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yuki Yamauchi
- Department of Orthopaedic Surgery, Medical Hospital, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takeshi Muneta
- Department of Orthopaedic Surgery, Medical Hospital, Tokyo Medical and Dental University, Tokyo, Japan
| | - Atsushi Okawa
- Department of Orthopaedic Surgery, Medical Hospital, Tokyo Medical and Dental University, Tokyo, Japan
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Kanazawa M, Nakashima Y, Ohishi M, Hamai S, Motomura G, Yamamoto T, Fukushi JI, Ushijima T, Hara D, Iwamoto Y. Pelvic tilt and movement during total hip arthroplasty in the lateral decubitus position. Mod Rheumatol 2015; 26:435-40. [PMID: 26375057 DOI: 10.3109/14397595.2015.1092914] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVES Total hip arthroplasty (THA) is often performed in the lateral decubitus (lateral) position. In this position, the pelvis may have various degrees of tilt leading to implant malposition. We sought to quantify the pelvic tilt in lateral position and further pelvic movement during surgery. METHODS In 95 cases with primary THA, three-dimensional pelvic tilts were quantified by superimposing images reconstructed from CT data onto antero-posterior radiographs taken in lateral position at set-up and after cup placement. Pelvises were fixed with a device compressing anterior superior iliac spines and sacrum. RESULTS Various degrees of pelvic tilt occurred compared to the supine position; sagittal: -3.1° (-25.5° to 10.2°), axial: 3.9° (-8.4° to 17°), coronal: 0.9° (-11.9° to 13.2°). Absolute changes more than 5° were observed 43%, 47%, and 12% in the sagittal, axial, and coronal planes, respectively. The more preoperative posterior pelvic tilt resulted in the more change in the sagittal plane. Further pelvic movement of about 3° in three planes were observed ranging from -11° to 20° after cup placement. CONCLUSION This study showed various pelvic tilt and movement during THA. As pelvic tilt directly alters the cup orientation, its changes should be well understood. Improved tools for positioning and holding the pelvis are required.
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Affiliation(s)
- Masayuki Kanazawa
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Yasuharu Nakashima
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Masanobu Ohishi
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Satoshi Hamai
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Goro Motomura
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Takuaki Yamamoto
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Jun-Ichi Fukushi
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Takahiro Ushijima
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Daisuke Hara
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
| | - Yukihide Iwamoto
- a Department of Orthopaedic Surgery , Kyushu University , Higashi-Ku , Fukuoka , Japan
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Abstract
BACKGROUND Fracture of the femoral stem in total hip arthroplasty (THA) is a rare complication. We have encountered 2 cases of neck fractures of the femoral stem occurring 9 and 12 years after THA. Morphological and biomechanical analysis were performed to investigate the mechanism of these fractures. METHOD A titanium alloy femoral stem having a slot with sharp corners (R = 0.2 mm) at the neck had been implanted in both cases. Fracture surfaces were examined by use of scanning electron microscopy (SEM). Stress concentration was simulated by using a finite element method (FEM) to compare slots with sharp (R = 0.2 mm) and smooth (R = 2 mm) corners. RESULTS Study of the retrieved stems revealed that neck fractures had occurred at the distal end of the slot in both cases. SEM revealed numerous fine fissures extending from the anterolateral edge, striations on the middle of the fracture surface, and dimples on the posteromedial surface, suggesting that the fractures had occurred from the anterolateral aspect toward the posteromedial aspect because of metallic fatigue. FEM analysis showed that mechanical stress was concentrated at the distal and anterolateral corners of the slot. Under 3500-N loading force, the stress at the sharp corner was 556 MPa, which was approximately twofold that at the smooth corner and exceeded the fatigue strength of titanium alloy. CONCLUSION These findings showed that the sharp corner of slot increased stress concentrations at the anterolateral aspect and led to the neck fractures.
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Balasundaram G, Storey DM, Webster TJ. Molecular plasma deposition: biologically inspired nanohydroxyapatite coatings on anodized nanotubular titanium for improving osteoblast density. Int J Nanomedicine 2015; 10:527-35. [PMID: 25609958 PMCID: PMC4298345 DOI: 10.2147/ijn.s65308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In order to begin to prepare a novel orthopedic implant that mimics the natural bone environment, the objective of this in vitro study was to synthesize nanocrystalline hydroxyapatite (NHA) and coat it on titanium (Ti) using molecular plasma deposition (MPD). NHA was synthesized through a wet chemical process followed by a hydrothermal treatment. NHA and micron sized hydroxyapatite (MHA) were prepared by processing NHA coatings at 500°C and 900°C, respectively. The coatings were characterized before and after sintering using scanning electron microscopy, atomic force microscopy, and X-ray diffraction. The results revealed that the post-MPD heat treatment of up to 500°C effectively restored the structural and topographical integrity of NHA. In order to determine the in vitro biological responses of the MPD-coated surfaces, the attachment and spreading of osteoblasts (bone-forming cells) on the uncoated, NHA-coated, and MHA-coated anodized Ti were investigated. Most importantly, the NHA-coated substrates supported a larger number of adherent cells than the MHA-coated and uncoated substrates. The morphology of these cells was assessed by scanning electron microscopy and the observed shapes were different for each substrate type. The present results are the first reports using MPD in the framework of hydroxyapatite coatings on Ti to enhance osteoblast responses and encourage further studies on MPD-based hydroxyapatite coatings on Ti for improved orthopedic applications.
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Affiliation(s)
| | | | - Thomas J Webster
- Department of Chemical Engineering, Northeastern University, Boston, MA, USA ; Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia
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Monument MJ, Lerman DM, Randall RL. Novel applications of osseointegration in orthopedic limb salvage surgery. Orthop Clin North Am 2015; 46:77-87. [PMID: 25435037 DOI: 10.1016/j.ocl.2014.09.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Osseointegration is a biologic process vital to modern endoprosthetic fixation in orthopedic surgery. Numerous engineering advancements have improved the utilization of this technology in orthopedics; however, issues such as stress shielding, aseptic loosening, and bone loss remain an ongoing challenge. These host responses are especially problematic in limb salvage surgery. Novel applications of osseointegration have been developed to address some of these fixation issues with massive tumor endoprostheses. This articles reviews osseointegration and emerging novel applications of this technology in limb salvage surgery and future prosthetics for amputees.
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Affiliation(s)
- Michael J Monument
- Sarcoma Services, Department of Orthopaedic Surgery, Huntsman Cancer Institute, Primary Children's Medical Center, University of Utah, 2000 Circle of Hope, Room 4260, Salt Lake City, UT 84112, USA
| | - Daniel M Lerman
- Sarcoma Services, Department of Orthopaedic Surgery, Huntsman Cancer Institute, Primary Children's Medical Center, University of Utah, 2000 Circle of Hope, Room 4260, Salt Lake City, UT 84112, USA
| | - R Lor Randall
- Sarcoma Services, Department of Orthopaedic Surgery, Huntsman Cancer Institute, Primary Children's Medical Center, University of Utah, 2000 Circle of Hope, Room 4260, Salt Lake City, UT 84112, USA.
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Nakashima Y, Mashima N, Imai H, Mitsugi N, Taki N, Mochida Y, Owan I, Arakaki K, Yamamoto T, Mawatari T, Motomura G, Ohishi M, Doi T, Kanazawa M, Iwamoto Y. Clinical and radiographic evaluation of total hip arthroplasties using porous tantalum modular acetabular components: 5-year follow-up of clinical trial. Mod Rheumatol 2014. [DOI: 10.3109/s10165-012-0618-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Yasuharu Nakashima
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Naohiko Mashima
- Department of Bone and Joint Surgery, Ehime University,
Shizugawa, Toon 791-0295, Japan
| | - Hiroshi Imai
- Department of Bone and Joint Surgery, Ehime University,
Shizugawa, Toon 791-0295, Japan
| | - Naoto Mitsugi
- Department of Orthopaedic Surgery, Yokohama City University Medical Center,
4-57 Urafune, Minamiku, Yokohama 232-0024, Japan
| | - Naoya Taki
- Department of Orthopaedic Surgery, Yokohama City University Medical Center,
4-57 Urafune, Minamiku, Yokohama 232-0024, Japan
| | - Yuichi Mochida
- Department of Orthopaedic Surgery, Yokohama City University Medical Center,
4-57 Urafune, Minamiku, Yokohama 232-0024, Japan
| | - Ichiro Owan
- Department of Orthopedic Surgery, University of the Ryukyu,
207 Uehara, Nishihara 903-0215, Japan
| | - Kaoru Arakaki
- Department of Orthopedic Surgery, University of the Ryukyu,
207 Uehara, Nishihara 903-0215, Japan
| | - Takuaki Yamamoto
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Taro Mawatari
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Goro Motomura
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Masanobu Ohishi
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Toshio Doi
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Masayuki Kanazawa
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Yukihide Iwamoto
- Department of Orthopaedic Surgery, Kyushu University,
1-3-3 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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So K, Kaneuji A, Matsumoto T, Matsuda S, Akiyama H. Is the bone-bonding ability of a cementless total hip prosthesis enhanced by alkaline and heat treatments? Clin Orthop Relat Res 2013; 471:3847-55. [PMID: 23539125 PMCID: PMC3825883 DOI: 10.1007/s11999-013-2945-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND Cementless total hip arthroplasty (THA) implants using alkaline and heat treatments were developed to enhance bone bonding. Although bone-bonding ability of the alkali- and heat-treated titanium surface has been demonstrated in animal studies, it remains unknown whether it enhances or provides durable bone bonding in humans. QUESTIONS/PURPOSES We therefore (1) determined long-term survivorship, function, and radiographic signs of failure of fixation of alkali- and heat-treated THA implants; and (2) histologically examined their bone-bonding ability in two human retrievals. METHODS We retrospectively reviewed 58 patients who underwent 70 primary THAs, of whom 67 were available for minimum followup of 8 years (average, 10 years; range, 8-12 years). Survival rate was calculated. Hip function was evaluated using the Japan Orthopaedic Association (JOA) hip scores, and radiographic signs of implant failure were determined from anteroposterior radiographs. Two retrieved implants were investigated histologically. RESULTS Using revision for any reason as the end point, the overall survival rate was 98% (95% confidence interval, 96%-100%) at 10 years. The patients' average JOA hip scores improved from 47 points preoperatively to 91 points at the time of the last followup. No implant had radiographic signs of loosening. Histologically we observed bone in the pores 2 weeks after implantation in one specimen and apparently direct bonding between bone and the titanium surface in its deep pores 8 years after implantation. CONCLUSIONS Cementless THA implants with alkaline and heat treatments showed a high survival rate. Further study is required to determine whether the treatment enhances direct bone bonding.
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Affiliation(s)
- Kazutaka So
- Department of Orthopaedic Surgery, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 Japan
| | - Ayumi Kaneuji
- Department of Orthopaedic Surgery, Kanazawa Medical University, Ishikawa, Japan
| | - Tadami Matsumoto
- Department of Orthopaedic Surgery, Kanazawa Medical University, Ishikawa, Japan
| | - Shuichi Matsuda
- Department of Orthopaedic Surgery, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 Japan
| | - Haruhiko Akiyama
- Department of Orthopaedic Surgery, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507 Japan
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Hara D, Nakashima Y, Yamamoto T, Higashihara S, Todo M, Hirata M, Akiyama M, Iwamoto Y. Late failure of annealed highly cross-linked polyethylene acetabular liner. J Mech Behav Biomed Mater 2013; 28:206-12. [DOI: 10.1016/j.jmbbm.2013.08.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/24/2013] [Accepted: 08/01/2013] [Indexed: 11/29/2022]
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Results at a minimum of 10 years of follow-up for AMS and PerFix HA-coated cementless total hip arthroplasty: impact of cross-linked polyethylene on implant longevity. J Orthop Sci 2013; 18:962-8. [PMID: 23963589 DOI: 10.1007/s00776-013-0456-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 07/30/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE The purpose of this study was to report results at a minimum of 10 years for hydroxyapatite (HA) coating on the titanium arc-sprayed cementless total hip arthroplasty (THA) and to evaluate the impact of cross-linked polyethylene (XLPE) on implant longevity. METHODS A total of 131 consecutive primary THAs in 123 patients using an AMS acetabular cup and a PerFix HA stem were retrospectively reviewed. Conventional PE was used for 62 hips (CPE group) and cross-linked PE for 69 hips (XLPE group), with mean follow-up periods of 13 and 11.5 years, respectively. These patients were reviewed using the Japanese Orthopaedic Association (JOA) Hip Score and evaluated in terms of PE wear, osteolysis, and implant survival. RESULTS The JOA score improved from 42.6 to 83.9 points at the final follow-up. The mean wear rate of 0.12 mm/year in the CPE group was significantly greater than that of XLPE at 0.007 mm/year. In the CPE group, ten (16.1 %) and two (3.2 %) hips, respectively, underwent PE exchange due to severe wear and acetabular revision due to loosening associated with osteolysis. Three patients had revision in the XLPE group: one cup for aseptic loosening, one PE for recurrent dislocation, and one stem for neck fracture. No evident osteolysis was seen in the XLPE group. Kaplan-Meier survivorship with any revision as the end point shows that the 12-year survival rate was 97.7 % for cups, 93.8 % for PE liners, and 99.2 % for stems. Multivariate analysis revealed that the use of XLPE significantly reduced the risk of revision, with the odds ratio (OR) of 4.3. CONCLUSIONS AMS and PerFix HA components in this series show excellent implant fixation; however, high rates of PE wear and subsequent osteolysis were limiting factors in long-term success. Low wear rates with XLPE suggest improved implant longevity.
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Combined anteversion technique reduced the dislocation in cementless total hip arthroplasty. INTERNATIONAL ORTHOPAEDICS 2013; 38:27-32. [PMID: 24026219 DOI: 10.1007/s00264-013-2091-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 08/16/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE The combined anteversion (CA) technique is a method in which the cup is placed according to the stem anteversion in total hip arthroplasty (THA). We examined whether the CA technique reduced the dislocation rate, and the distribution of CA with the manual placement of the cup. METHODS We retrospectively reviewed 634 hips in 579 patients with primary cementless THA. In 230 hips using the CA technique [CA(+)], a CA of 50 ± 10° was the aim. In the remaining 404 hips [CA(-)], the cup was first placed targeting 20° of anteversion. The post-operative CA was measured using the computed tomography (CT) images in 111 hips. RESULTS One hip (0.4%) had a dislocation in the CA(+) group, whereas ten hips (2.5%) had a dislocation in the CA(-) group. A multivariate analysis showed that primary diagnosis, head size and CA technique significantly influenced the dislocation rate. Patients in the CA(-) group were 5.8 times more likely to have a dislocation compared to the CA(+) group. In the 111 hips with CT images, 81 hips (73.0%) achieved the intended CA. CONCLUSIONS Although the manual placement of the cup resulted in 27% of outliers from the intended CA, the CA technique significantly reduced the dislocation after primary THA.
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Troiano NW, Kacena MA. Bone Implants: Processing, Embedding, Cutting, and Histopathology. J Histotechnol 2013. [DOI: 10.1179/his.2006.29.4.253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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The effect of surface treatment of titanium with sand-blasting/acid-etching or hydroxyapatite-coating and application of bone morphogenetic protein-2 on attachment, proliferation, and differentiation of stem cells derived from buccal fat pad. Tissue Eng Regen Med 2013. [DOI: 10.1007/s13770-013-0011-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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27
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Sato T, Nakashima Y, Akiyama M, Yamamoto T, Mawatari T, Itokawa T, Ohishi M, Motomura G, Hirata M, Iwamoto Y. Wear resistant performance of highly cross-linked and annealed ultra-high molecular weight polyethylene against ceramic heads in total hip arthroplasty. J Orthop Res 2012; 30:2031-7. [PMID: 22644564 DOI: 10.1002/jor.22148] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Accepted: 05/01/2012] [Indexed: 02/04/2023]
Abstract
The purpose of this study was to examine the effects of ceramic femoral head material, size, and implantation periods on the wear of annealed, cross-linked ultra-high molecular weight polyethylene (UHMWPE) (XLPE) in total hip arthroplasty compared to non-cross-linked conventional UHMWPE (CPE). XLPE was fabricated by cross-linking with 60 kGy irradiation and annealing. Femoral heads made from zirconia and alumina ceramics and cobalt-chrome (CoCr) of 22 or 26 mm diameter were used. In this retrospective cohort study, the femoral head penetration into the cup was measured digitally on radiographs of 367 hips with XLPE and 64 hips with CPE. The average follow-up periods were 6.3 and 11.9 years, respectively. Both XLPE creep and wear rates were significantly lower than those of CPE (0.19 mm vs. 0.44 mm, 0.0001 mm/year vs. 0.09 mm/year, respectively). Zirconia displayed increased wear rates compared to alumina in CPE; however, there was no difference among head materials in XLPE (0.0008, 0.00007, and -0.009 mm/year for zirconia, alumina, and CoCr, respectively). Neither head size or implantation period impacted XLPE wear. In contrast to CPE, XLPE displayed low wear rates surpassing the effects of varying femoral head material, size, implantation period, and patient demographics. Further follow-up is required to determine the long-term clinical performance of the annealed XLPE.
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Affiliation(s)
- Taishi Sato
- Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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Monjo M, Ramis JM, Rønold HJ, Taxt-Lamolle SF, Ellingsen JE, Lyngstadaas SP. Correlation between molecular signals and bone bonding to titanium implants. Clin Oral Implants Res 2012; 24:1035-43. [PMID: 22587025 DOI: 10.1111/j.1600-0501.2012.02496.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/06/2012] [Indexed: 11/30/2022]
Abstract
OBJECTIVES A better understanding of the biological processes controlling osseointegration at the bone-to-implant interface is needed. The aim of this study was to examine which are the molecular and biochemical variables that are significantly related to osseointegration, using multiple regression analysis. MATERIALS AND METHODS Titanium coins were placed into the tibial cortical bone of New Zealand White rabbits and evaluated using pull-out test after 4 and 8 weeks of healing. Correlations between pull-out and several markers from tissue fluid (Lactate dehydrogenase [LDH] and Alkaline phosphatase [ALP] activities and total protein content) and peri-implant bone tissue (total protein, RNA and DNA content, implant area covered with bone and gene expression of osteoblast, osteoclast and inflammation markers) were used to assess the importance of these parameters in bone healing and in relation to implant performance. RESULTS Our results showed a negative correlation between the content of DNA, RNA and total protein at the peri-implant bone tissue and the pull-out force, indicating that as bone matures and implant becomes more osseointegrated, the organic content of bone decreases. The negative correlation found between pull-out force and ALP activity pointed to a delayed healing in implants with lower pull-out values and primary mineralization still ongoing. LDH activity and total protein content in the tissue fluid were as well negatively correlated with the pull-out force. Finally, a positive correlation was observed between the pull-out force and the expression of the osteoblast and the bone resorption markers, being osteocalcin and collagen-I the best predictive markers for osseointegration after 4 and 8 weeks of healing respectively. CONCLUSIONS These results suggest that the evaluation of these markers could be relevant for the assessment of new implant surfaces for rapid bone healing and improved implant performance.
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Affiliation(s)
- Marta Monjo
- Department of Fundamental Biology and Health Sciences, Research Institute on Health Sciences, University of Balearic Islands, Carretera de Valdemossa km. 7.5, Palma de Mallorca, Spain.
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Nakashima Y, Mashima N, Imai H, Mitsugi N, Taki N, Mochida Y, Owan I, Arakaki K, Yamamoto T, Mawatari T, Motomura G, Ohishi M, Doi T, Kanazawa M, Iwamoto Y. Clinical and radiographic evaluation of total hip arthroplasties using porous tantalum modular acetabular components: 5-year follow-up of clinical trial. Mod Rheumatol 2012; 23:112-8. [PMID: 22395477 DOI: 10.1007/s10165-012-0618-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Accepted: 02/13/2012] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Porous tantalum is a biomaterial newly applied for artificial joints. We present here 5-years follow-up report of a multicenter clinical trial of total hip arthroplasties (THA) with porous tantalum modular acetabular component (modular PTC). METHODS Study participants received 82 hips in 79 cases, with 61.2 months follow-up on average. Age at operation was 60.9 years. Clinical results were evaluated using Merle d'Aubigne Postel score. Presence of implant loosening, periacetabular radiolucency, osteolysis, and gap filling were examined for radiographic results. RESULTS Merle d'Aubigne Postel score improved from 10.0 to 16.4 points. All PTC were radiographically stable, with no evidence of progressive radiolucencies. Average polyethylene wear rate was 0.004 mm/year, with no periacetabular osteolysis. Fifteen hips (18.3%) showed a gap >1 mm; however, all showed bone filling within 12 months. PTC with oversized reaming was significantly less likely to have a gap. No implant failure was noted related to modularity. Resulting survival rate of modular PTC was 100% at 5 years. CONCLUSIONS Modular PTC showed excellent results at 5-years of follow-up. Some hips showed periacetabular gaps, which were filled with bone within 1 year. Further follow-up was needed to determine long-term efficacy.
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Affiliation(s)
- Yasuharu Nakashima
- Department of Orthopaedic Surgery, Kyushu University, 1-3-3 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
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Yonekura Y, Miyamoto H, Shimazaki T, Ando Y, Noda I, Mawatari M, Hotokebuchi T. Osteoconductivity of thermal-sprayed silver-containing hydroxyapatite coating in the rat tibia. ACTA ACUST UNITED AC 2011; 93:644-9. [DOI: 10.1302/0301-620x.93b5.25518] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A silver-containing hydroxyapatite (Ag-HA) coating has been developed using thermal spraying technology. We evaluated the osteoconductivity of this coating on titanium (Ti) implants in rat tibiae in relation to bacterial infection in joint replacement. At 12 weeks, the mean affinity indices of bone formation of a Ti, an HA, a 3%Ag-HA and a 50%Ag-HA coating were 97.3%, 84.9%, 81.0% and 40.5%, respectively. The mean affinity indices of bone contact of these four coatings were 18.8%, 83.7%, 77.2% and 40.5%, respectively. The indices of bone formation and bone contact around the implant of the 3%Ag-HA coating were similar to those of the HA coating, and no significant differences were found between them (bone formation, p = 0.99; bone contact, p = 0.957). However, inhibition of bone formation was observed with the 50%Ag-HA coating. These results indicate that the 3%Ag-HA coating has low toxicity and good osteoconductivity, and that the effect of silver toxicity on osteoconductivity depends on the dose.
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Affiliation(s)
| | - H. Miyamoto
- Department of Pathology and Microbiology, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan
| | | | - Y. Ando
- Research Department, Japan Medical Materials Corporation, 3-3-31 Miyahara, Yodogawa-ku, Osaka, Japan
| | - I. Noda
- Research Department, Japan Medical Materials Corporation, 3-3-31 Miyahara, Yodogawa-ku, Osaka, Japan
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Khanuja HS, Vakil JJ, Goddard MS, Mont MA. Cementless femoral fixation in total hip arthroplasty. J Bone Joint Surg Am 2011; 93:500-9. [PMID: 21368083 DOI: 10.2106/jbjs.j.00774] [Citation(s) in RCA: 319] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A number of cementless femoral stems are associated with excellent long-term survivorship. Cementless designs differ from one another in terms of geometry and the means of obtaining initial fixation. Strict classification of stem designs is important in order to compare results among series. Loosening and thigh pain are less prevalent with modern stem designs. Stress-shielding is present in most cases, even with newer stem designs.
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Affiliation(s)
- Harpal S Khanuja
- Center for Joint Preservation and Replacement, The Rubin Institute for Advanced Orthopedics, Sinai Hospital of Baltimore, 2401 West Belvedere Avenue, Baltimore, MD 21215, USA.
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Hayashi K, Fotovati A, Abu Ali S, Nakamura Y, Inagaki M, Naito M. Effect of a prostaglandin EP4 receptor agonist on early fixation of hydroxyapatite/titanium composite- and titanium-coated rough-surfaced implants in ovariectomized rats. J Biomed Mater Res A 2010; 92:1202-9. [PMID: 19322876 DOI: 10.1002/jbm.a.32444] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The agonist of the prostaglandin EP4 receptor can increase bone density in osteoporosis. Using ovariectomized (OVX) and sham-operated (SO) rats, the effects of the EP4 receptor agonist, ONO-4819, and hydroxyapatite (HA) on implant-bone fixation in implants with a rough surface were investigated. Female Wistar rats (12 weeks old) were divided into either SO or bilateral OVX groups. Twenty four weeks later, either hydroxyapatite/titanium (HA/Ti) composite-coated or Ti-coated implants were implanted into the femora, and the animals were treated with either ONO-4819 or saline for 4 weeks. The fixation strength of the HA/Ti-coated implants was higher than that of the Ti-coated implants in the saline-treated OVX rats. In the OVX rats, ONO-4819 enhanced fixation of the rough Ti-coated implants to levels similar to that of HA/Ti-coated implants. These data suggest that a combination of treatment with an EP4 receptor agonist and a rough-surfaced implant might be useful in increasing the early fixation of cement-less arthroplasty, particularly in elderly patients with osteoporosis.
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Affiliation(s)
- K Hayashi
- Department of Orthopaedic Surgery, Orthpaedic Research Laboratory, Fukuoka Wajiro Hospital, Higashi-ku, Fukuoka, Japan
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Shimazaki T, Miyamoto H, Ando Y, Noda I, Yonekura Y, Kawano S, Miyazaki M, Mawatari M, Hotokebuchi T. In vivo antibacterial and silver-releasing properties of novel thermal sprayed silver-containing hydroxyapatite coating. J Biomed Mater Res B Appl Biomater 2010; 92:386-9. [PMID: 19904818 DOI: 10.1002/jbm.b.31526] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
One of the serious postoperative complications associated with joint replacement is bacterial infection. In addressing this problem, we have previously described the development of a novel thermal spraying technology combining silver (Ag) showing antibacterial activity with hydroxyapatite (HA) displaying good biocompatibility and osteoconductivity, and reported the in vitro properties. This study evaluated serum Ag ion concentrations and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) using a subcutaneous rat model. HA loaded with 3 wt % of silver oxide (Ag-HA) and plain HA were sprayed on the surface of titanium disks. Ag-HA- or HA-coated samples were implanted into the back subcutaneous pockets of male Sprague-Dawley rats. Mean serum Ag ion concentration in the Ag-HA group increased to more than 50 ppb by 48 h after implantation, then decreased gradually to baseline levels. Mean (+/- standard error of the mean) number of viable MRSA on HA coating was (1.5 +/- 0.5) x 10(5), which is significantly more than the (1.1 +/- 0.4) x 10(4) on Ag-HA coating (p < 0.001). Ag-HA coating offers good abilities to release Ag ions and kill MRSA in vivo.
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Affiliation(s)
- Takafumi Shimazaki
- Department of Orthopedic Surgery, Faculty of Medicine, Saga University, Saga 849-8501, Japan.
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Ando Y, Miyamoto H, Noda I, Sakurai N, Akiyama T, Yonekura Y, Shimazaki T, Miyazaki M, Mawatari M, Hotokebuchi T. Calcium phosphate coating containing silver shows high antibacterial activity and low cytotoxicity and inhibits bacterial adhesion. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2010. [DOI: 10.1016/j.msec.2009.09.015] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Noda I, Miyaji F, Ando Y, Miyamoto H, Shimazaki T, Yonekura Y, Miyazaki M, Mawatari M, Hotokebuchi T. Development of novel thermal sprayed antibacterial coating and evaluation of release properties of silver ions. J Biomed Mater Res B Appl Biomater 2009; 89:456-465. [PMID: 18937261 DOI: 10.1002/jbm.b.31235] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Several studies have addressed the use of antibacterial coating to reduce implant-associated infections. In this study, novel silver (Ag)-containing calcium-phosphate (CP) coating technology based on the thermal spraying method was developed. The coating's physical and chemical properties, in vitro antibacterial activity, hydroxyapatite (HA)-forming ability, and release of Ag ions were evaluated. An amorphous structure of the coating was confirmed by X-ray diffraction, and Ag residue in the coating was determined by elementary analysis. The coating showed strong antibacterial activity to methicillin-resistant Staphylococcus aureus in fetal bovine serum (FBS) along with HA-forming ability in simulated body fluid. Therefore, it is expected that the coating would confer antibacterial and bone bonding abilities to the implant surface. Time course release testing of Ag ions from the coating on immersion in FBS showed pronounced Ag release for up to 24 h after immersion, with consistent strong antibacterial activity at the early postoperative stage. In repeated testing, the amount of released Ag ions was about 6500 parts per billion (ppb, microg/L) for the first release test, after which it gradually decreased. However, retention of significant release of Ag ions after a sixth repeat implies that Ag release from the coating is slow in FBS.
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Affiliation(s)
- Iwao Noda
- Research Department, Japan Medical Materials Corporation, Osaka 532-0003, Japan
| | - Fumiaki Miyaji
- Research Department, Japan Medical Materials Corporation, Osaka 532-0003, Japan
| | - Yoshiki Ando
- Research Department, Japan Medical Materials Corporation, Osaka 532-0003, Japan.,Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Hiroshi Miyamoto
- Department of Pathology and Microbiology, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Takafumi Shimazaki
- Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Yutaka Yonekura
- Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Masaki Miyazaki
- Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Masaaki Mawatari
- Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Saga 849-8501, Japan
| | - Takao Hotokebuchi
- Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Saga 849-8501, Japan
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Kurumada KI, Susa K, Sugano Y, Takahashi M, Pan G. Formation of uniform hydroxyapatite nanocoating triggered by nucleation at carboxylic groups embedded in ethylene/acrylic acid copolymer microspheres. Colloids Surf A Physicochem Eng Asp 2008. [DOI: 10.1016/j.colsurfa.2008.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nakamura Y, Hayashi K, Abu-Ali S, Naito M, Fotovati A. Effect of preoperative combined treatment with alendronate and calcitriol on fixation of hydroxyapatite-coated implants in ovariectomized rats. J Bone Joint Surg Am 2008; 90:824-32. [PMID: 18381321 DOI: 10.2106/jbjs.g.00635] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Osteoporosis is a potential risk factor affecting implant stability following total joint arthroplasty. Bisphosphonates are potent inhibitors of osteoblastic bone resorption, and vitamin D is an important hormone involved in the regulation of calcium metabolism. We investigated the benefit of preoperative treatment with alendronate, vitamin D (calcitriol), or a combination of these substances on fixation of hydroxyapatite-coated implants in an ovariectomized rat model of osteoporosis. METHODS Of sixty-four female rats in the study, fifty-six underwent ovariectomy and eight, a sham operation. A hydroxyapatite-coated femoral implant and an uncoated implant were implanted in all rats seven months after the ovariectomy or the sham operation. Of the fifty-six rats that underwent ovariectomy, eight served as the control group. The remaining forty-eight were treated with alendronate, calcitriol, or a combination of these agents either starting eight weeks before implantation of the rod or starting immediately after implantation. The treatment was continued until four weeks after the implantation. Four weeks after the implantation, the total and cancellous bone mineral density at the proximal part of the tibia and the shear strength of the bone-implant interface were measured in all rats. RESULTS Although total bone mineral density increased in all of the alendronate-treated groups, compared with that in the ovariectomized control group, cancellous bone mineral density increased only in the group pretreated with both alendronate and calcitriol. The implant stability in the ovariectomized control rats was significantly decreased compared with that in the sham-operation rats. While treatment with alendronate only or calcitriol only did not improve the stability of the implants, treatment with a combination of alendronate and calcitriol, starting preoperatively, significantly improved the stability of the hydroxyapatite-coated implants. CONCLUSIONS Treatment with a combination of alendronate and calcitriol, starting preoperatively, can improve cancellous bone mineral density and the stability of hydroxyapatite-coated implants in an osteoporotic rat.
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Affiliation(s)
- Yoshinari Nakamura
- Department of Orthopaedic Surgery, Fukuoka University School of Medicine, 7-45-1, Nanakuma, Jonan-ku, Fukuoka 814-0180, Japan
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Nakada H, Sakae T, LeGeros RZ, LeGeros JP, Suwa T, Numata Y, Kobayashi K. Early Tissue Response to Modified Implant Surfaces Using Back Scattered Imaging. IMPLANT DENT 2007; 16:281-9. [PMID: 17846544 DOI: 10.1097/id.0b013e3180e92a78] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE It is now well known that implant surface properties affect osseointegration. Grit-blasting with abrasives and coating by plasma are methods to modify implant surfaces. This study aimed to compare the direction of new bone formation associated with three types of surfaces. MATERIALS AND METHODS Titanium (Ti) alloy rods grit-blasted with alumina abrasive (Group 1, G1), with apatitic abrasive (Group 2, G2), and with apatitic abrasive and plasma-sprayed with hydroxyapatite (Group 3, G3) were implanted in surgically created defects in tibias of New Zealand white rabbits for 2 and 4 weeks. After sacrifice, the implants and surrounding bones were obtained and analyzed using back scattered imaging. RESULTS Differences in patterns of bone formation among the groups were observed: originating from the cortical bone towards the implant surface (Type A), surrounding the implant (Type B) and originating from the medullary cavity (Type C). G1 and G3 showed Types A and B while G2 exhibited Types A, B and C. After 4 weeks, greater amount of new bone was observed in G2 group compared with those in G1 and G3 groups. CONCLUSIONS This study demonstrated that patterns of bone formation are influenced by methods of surface modification.
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Affiliation(s)
- Hiroshi Nakada
- Dept. of Gnatho-Oral Prosthetic Rehabilitation, Nihon University School of Dentistry at Matsudo, Japan.
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Hasegawa M, Sudo A, Uchida A. Alumina ceramic-on-ceramic total hip replacement with a layered acetabular component. ACTA ACUST UNITED AC 2006; 88:877-82. [PMID: 16798988 DOI: 10.1302/0301-620x.88b7.17675] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A modular layered acetabular component (metal-polyethylene-ceramic) was developed in Japan for use in alumina ceramic-on-ceramic total hip replacement. Between May 1999 and July 2000, we performed 35 alumina ceramic-on-ceramic total hip replacements in 30 consecutive patients, using this layered component and evaluated the clinical and radiological results over a mean follow-up of 5.8 years (5 to 6.5). A total of six hips underwent revision, one for infection, two for dislocation with loosening of the acetabular component, two for alumina liner fractures and one for component dissociation with pelvic osteolysis. There were no fractures of the ceramic heads, and no loosening of the femoral or acetabular component in the unrevised hips was seen at final follow-up. Osteolysis was not observed in any of the unrevised hips. The survivorship analysis at six years after surgery was 83%. The layered acetabular component in our experience, has poor durability because of unexpected mechanical failures including alumina liner fracture and component dissociation.
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Affiliation(s)
- M Hasegawa
- Department of Orthopaedic Surgery, Mie University Graduate, School of Medicine, 2-174, Edobashi, Tsu City, Mie 514-8507, Japan.
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Suzuki T, Fujibayashi S, Nakagawa Y, Noda I, Nakamura T. Ability of zirconia double coated with titanium and hydroxyapatite to bond to bone under load-bearing conditions. Biomaterials 2006; 27:996-1002. [PMID: 16115676 DOI: 10.1016/j.biomaterials.2005.07.026] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Accepted: 07/21/2005] [Indexed: 11/29/2022]
Abstract
As a preclinical study, we evaluated the ability of hydroxyapatite and titanium on zirconia (HTOZ) to bond to bone under load-bearing conditions in animal experiments. HTOZ, HA, and Ti on Co-Cr alloy (HTOC) and Ti on Co-Cr alloy (TOC) were implanted into the weight-bearing portion of the femoral condyles of nine beagle dogs. Femurs were extracted 4, 12, and 52 weeks after implantation and examined mechanically by pullout testing, and histologically by toluidine blue staining, SEM, and calculation of the affinity index. The interfacial shear strengths (mean+/-SD) of the HTOZ, HTOC, and TOC groups were 4.42+/-0.453, 3.90+/-0.903, and 4.08+/-0.790 MPa at 4 weeks; 6.82+/-2.64, 6.00+/-1.88, and 6.63+/-1.63 MPa at 12 weeks; and 13.98+/-1.94, 11.95+/-1.51, and 10.78+/-0.83 MPa at 52 weeks. There were no significant differences in the interfacial shear strengths between the three groups at any time. Affinity indices (mean+/-SD) obtained from SEM images of the HTOZ, HTOC, and TOC groups were 49.6+/-6.52%, 43.3+/-10.43%, and 23.7+/-3.95% at 4 weeks; 55.0+/-6.72%, 51.5+/-3.07%, and 28.6+/-4.09% at 12 weeks; and 59.1+/-6.73%, 63.0+/-6.40%, and 34.3+/-6.72% at 52 weeks. HA-coated implants (HTOZ, HTOC) had significantly higher affinity indices than non-HA-coated implants (TOC) at all times. HTOZ has the ability to bond to bone equivalent to HTOC and TOC. HTOZ is an excellent material for components of cementless joint prostheses.
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Affiliation(s)
- Takashi Suzuki
- Department of Orthopaedic Surgery, Kyoto University Graduate School of Medicine, Shogoin-Kawaharacho 54, Sakyo-ku, Kyoto 606-8507, Japan
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Abstract
Titanium and some of its alloys are widely used as load-bearing implant materials. In particular, titanium-zirconium (Ti-Zr) alloys have a high potential for biomedical applications due to the excellent biocompatibility of both Ti and Zr. Nevertheless, the surfaces of the Ti-Zr alloys need to be modified to provide the implant material’s bioactivity. In the present study, an alkali-heat (AH) treatment process followed by the soaking in simulated body fluid (SBF) was attempted for the preparation of calcium phosphate (CaP) coatings on the surface of the TiZr alloy. Phase transformation, surface morphology, and interfacial microstructure were investigated using scanning electron microscope (SEM) with an energy-dispersive electron probe X-ray analyser (EDS). The results indicate that the AH treatment produced a nano-porous bioactive sodium titanate / zirconate hydrogel surface layer which induced the deposition of a Ca-P layer during soaking in the SBF. This Ca-P layer on the TiZr alloy surface can be expected to bond to the surrounding bones directly after implantation.
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Liu Y, Li JP, Hunziker EB, de Groot K. Incorporation of growth factors into medical devices via biomimetic coatings. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2006; 364:233-248. [PMID: 18272464 DOI: 10.1098/rsta.2005.1685] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Orthopaedic and dental surgeons are fully aware of the need for implants to bond well with the surrounding living bone if long-lasting clinical success is to be achieved. For example, well-bonded hip implants have a 10 year failure rate, which is lowered fivefold if bonding is poor or absent. The techniques that are currently available to impart implant surfaces with the desired osteoconductive properties are essentially limited. To overcome the inherent difficulties, we have developed a 'biomimetic' coating process. By this means, implants with complex surface geometries, such as porous spinal implants, can be furnished with a bone-bonding surface. Furthermore, these coatings can be rendered osteoinductive as well as osteoconductive (by incorporating osteogenic agents). Using this facility, we have induced bone formation at an ectopic site in rats, and have accelerated osseointegration (bone bonding) at an orthotopic dental site in adult miniature pigs. Our preliminary results indicated that these osteoinductive dental implants bond with surrounding bone within one week instead of the usual three weeks. We believe that surfaces coated with biomimetic coatings into which osteogenic growth factors are incorporated hold great potential for use in clinical orthopaedics and dentistry.
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Affiliation(s)
- Y Liu
- Twente University, Professor Bronkhorstlaan 10D, 3723 MB Bilthoven, The Netherlands.
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Xue W, Liu X, Zheng X, Ding C. In vivo evaluation of plasma-sprayed titanium coating after alkali modification. Biomaterials 2005; 26:3029-37. [PMID: 15603798 DOI: 10.1016/j.biomaterials.2004.09.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Accepted: 09/02/2004] [Indexed: 10/26/2022]
Abstract
In this paper, plasma-sprayed titanium coatings were modified by alkali treatment. The changes in chemical composition and structure of coatings were examined by SEM and AES. The results obtained indicated that a net-like microscopic texture feature, which was full of the interconnected fine porosity, appeared on the surface of alkali-modified titanium coatings. The surface chemical composition was also altered by alkali modification. A sodium titanate compound was formed on the surface of the titanium coating and replaced the native passivating oxide layer. Its thickness was measured as about 150 nm which was about 10 times of that of the as-sprayed coating. The bone bonding ability of titanium coatings were investigated using a canine model. The histological examination and SEM observation demonstrated that more new bone was formed on the surface of alkali-modified implants and grew more rapidly into the porosity. The alkali-modified implants were found to appose directly to the surrounding bone. In contrast, a gap was observed at the interface between the as-sprayed implants and bone. The push-out test showed that alkali-modified implants had a higher shear strength than as-sprayed implants after 1 month of implantation. An interfacial layer, containing Ti, Ca and P, was found to form at the interface between bone and the alkali-modified implant by EDS analysis.
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Affiliation(s)
- Weichang Xue
- Plasma Spray Laboratory, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi road, Shanghai 200050, People's Republic of China.
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Kusakabe H, Sakamaki T, Nihei K, Oyama Y, Yanagimoto S, Ichimiya M, Kimura J, Toyama Y. Osseointegration of a hydroxyapatite-coated multilayered mesh stem. Biomaterials 2004; 25:2957-69. [PMID: 14967528 DOI: 10.1016/j.biomaterials.2003.09.090] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2003] [Accepted: 09/22/2003] [Indexed: 11/21/2022]
Abstract
A new type of porous coating for hip prostheses called "multilayered mesh" was tested under weight-bearing conditions. The surface of the stem is constructed of titanium mesh produced by etching. The hip stems of hydroxyapatite (HA)-coated multilayered mesh and conventional beads were implanted into canine right hips, and animals were killed 3, 6 and 10 weeks and 6 and 12 months after implantation. Shear strength between the implant and the bone was evaluated by the push-out test. Bone ingrowth was calculated from backscattered electron imaging-scanning electron microscopy (BEI-SEM) images of transverse sections. Toluidine blue stained sections and the BEI-SEM images were evaluated histologically. The break sites of the specimens after the push-out test were evaluated on BEI-SEM images of longitudinal sections. The mean push-out strength of the HA-coated multilayered mesh samples was greater than that of the beads-coated samples every time tested, and the HA-coated multilayered mesh implants had significantly stronger push-out strength at 3 and 6 weeks (p<0.05). The strength of the HA-coated multilayered mesh implants was even greater at 6 and 12 months, whereas the strength of the beads-coated samples decreased. The HA-coated multilayered mesh implants showed significantly higher percentages of bone ingrowth than the beads-coated implants every time tested, except at 6 months (p<0.05). At 6 and 12 months, the bone ingrowth data for the HA-coated multilayered mesh implants increased, whereas it decreased for the beads-coated implants. The new bone formation had reached the bottom of the porous area of the HA-coated multilayered mesh surface by 3 weeks, but not had reached the bottom of the conventional beads surface. At 6 and 12 months, the smaller pores of the bead surface stopped the thickening of trabecular bone, and at 12 months, the break sites were at the bone-implant interface of the bead surface, whereas they were on the bone side of the HA-coated multilayered mesh surface. The difference between the break sites was significant at 12 months (p<0.05). The HA-coated multilayered mesh stem provided faster, stronger, and more durable osseointegration than the conventional bead stem.
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Affiliation(s)
- Hiroshi Kusakabe
- Department of Orthopedic Surgery, Keio University School of Medicine, Tokyo, Japan.
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Wang M. Bioactive Materials and Processing. BIOLOGICAL AND MEDICAL PHYSICS, BIOMEDICAL ENGINEERING 2004. [DOI: 10.1007/978-3-662-06104-6_1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Nishiguchi S, Fujibayashi S, Kim HM, Kokubo T, Nakamura T. Biology of alkali- and heat-treated titanium implants. ACTA ACUST UNITED AC 2003; 67:26-35. [PMID: 14517858 DOI: 10.1002/jbm.a.10540] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In cementless fixation systems, surface character is an important factor. Alkali and heat treatments of titanium metal have been shown to produce strong bonding to bone and a higher ongrowth rate. In this study we examined the effect of alkali and heat treatments on titanium rods in an intramedullary rabbit femur model, in regard to the cementless hip stem. The implant rods were 5 mm in diameter and 25 mm in length. Half of the implants were immersed in 5 mol/L sodium hydroxide solution and heated at 600 degrees C for 1 h (AH implants), and the other half were untreated (CL implants). The rods were implanted into the distal femur of the rabbits; AH implants into the left femur and CL implants into the right. The bone-implant interfaces were evaluated at 3, 6, and 12 weeks after implantation. Pull-out tests showed that the AH implants had a significantly higher bonding strength to bone than the CL implants at each time point. As postoperative time elapsed, histological examination revealed that new bone formed on the surface of both types of implants, but significantly more bone made direct contact with the surface of the AH implants. At 12 weeks, approximately 56% of the whole surface of the AH implants was covered with the bone. In conclusion, alkali- and heat-treated titanium offers strong bone bonding and a high affinity to bone as opposed to a conventional mechanical interlocking mechanism. Alkali and heat treatments of titanium may be suitable surface treatments for cementless joint replacement implants.
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Affiliation(s)
- Shigeru Nishiguchi
- Department of Orthopaedic Surgery, Faculty of Medicine, Kyoto University, Shougoin-kawaharacho 54, Sakyo-ku, Kyoto 606-8507, Japan.
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Aebli N, Krebs J, Stich H, Schawalder P, Walton M, Schwenke D, Gruner H, Gasser B, Theis JC. In vivo comparison of the osseointegration of vacuum plasma sprayed titanium- and hydroxyapatite-coated implants. J Biomed Mater Res A 2003; 66:356-63. [PMID: 12889006 DOI: 10.1002/jbm.a.10508] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
For the last 15 years, orthopedic implants have been coated with hydroxyapatite (HA) to improve implant fixation. The osteoconductive effect of HA coatings has been demonstrated in experimental and clinical studies. However, there are ongoing developments to improve the quality of HA coatings. The objective of this study was to investigate whether a rough and highly crystalline HA coating applied by vacuum plasma spraying (VPS) had a positive effect on the osseointegration of special, high-grade titanium (Ti) implants with the same surface roughness. Ti alloy implants were coated (VPS) with special, high-grade Ti or HA. The osseointegration of the implants was evaluated by either light microscopy or pullout tests after 1, 2, and 4 weeks of unloaded implantation in the cancellous bone of 18 sheep. The interface shear strength increased significantly over all time intervals. By 4 weeks, values had reached approximately 10N/mm(2). However, the difference between the coatings was not significant at any time interval. Direct bone-implant contact was significantly different between the coatings after 2 and 4 weeks, and reached 46% for Ti and 68% for HA implants by 4 weeks. This study indicates that the use of a rough and highly crystalline HA coating, applied by VPS, enhances early osseointegration. Accelerated establishment of secondary implant fixation decreases the risk of early loosening.
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Affiliation(s)
- Nikolaus Aebli
- Department of Orthopaedic Surgery, University of Otago, Dunedin, New Zealand.
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Takahashi K, Yasunaga Y, Hisatome T, Ikuta Y, Ochi M. Second- and third-generation Omniflex modular femoral stem: results 3 to 8 years after surgery. J Arthroplasty 2003; 18:600-4. [PMID: 12934212 DOI: 10.1016/s0883-5403(03)00199-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Primary cementless total hip arthroplasty (THA) using the Omniflex modular femoral stem was conducted on 73 hips in 70 patients. The arc deposition (AD)-type stem was used in 26 hips, and the hydroxyapatite (HA)-type stem was used in 47 hips. The mean follow-up period of patients in the AD group was 78 (range, 61-96) months and that of patients in the HA group was 52 (range, 36-61) months. Clinically, improvement in the Harris hip score occurred in all cases. Thigh pain was reported in 3 (11.5%) AD hips and in 1 (2.1%) HA hip. Radiologically, bone ingrowth fixation was seen in 88.5% of the AD group and in 97.9% of the HA group. No subtrochanteric stress shielding, stem migration of > 2 mm, or revision THA occurred. The second- and third- generation Omniflex stems are useful cementless devices resulting in favorable initial biologic fixation and little bone atrophy at mid-term follow-up.
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Affiliation(s)
- Kazuhiro Takahashi
- Department of Orthopaedic Surgery, Hiroshima University School of Medicine, Hiroshima, Japan
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Rønold HJ, Ellingsen JE. Effect of micro-roughness produced by TiO2 blasting--tensile testing of bone attachment by using coin-shaped implants. Biomaterials 2002; 23:4211-9. [PMID: 12194524 DOI: 10.1016/s0142-9612(02)00167-9] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of the present study was to examine bone response to micro-rough titanium implants. Forty coin-shaped implants were divided into eight groups according to their surface roughness. The first group had electropolished surfaces. The surfaces of implant groups 2-8 were blasted with TiO2 particles with incremental grain sizes ranging from 7.5-12.5 to 270-330 microns. Five implants from each group were placed into the cortical bone of the proximal tibia in New Zealand Black rabbits. To avoid bone overgrowth during the retention phase the implants were fitted into tight polytetrafluoroethylene (PTFE) caps leaving only the flat test surface exposed to bone. The healing period was set to 10 weeks, and implants with attached bone were evaluated using a tensile testing machine. In groups 1-7 a significant correlation between the micro-roughness of the implant surfaces and retention strength was observed. Maximum bone bonding was observed with implants blasted with 180-220 microns grain size (group 7). Blasting with larger TiO2 particles appeared to decrease the effect. The findings suggest that the best grain size of TiO2 particles for optimising retention of titanium implants in cortical bone should be in the 180-220 microns range.
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Affiliation(s)
- Hans Jacob Rønold
- Department of Prosthetic Dentistry and Oral Function, and Oral Research Laboratory, Dental Faculty, University of Oslo, P.O. Box 1109, Blindern, N-0317 Oslo, Norway.
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Knabe C, Klar F, Fitzner R, Radlanski RJ, Gross U. In vitro investigation of titanium and hydroxyapatite dental implant surfaces using a rat bone marrow stromal cell culture system. Biomaterials 2002; 23:3235-45. [PMID: 12102195 DOI: 10.1016/s0142-9612(02)00078-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this study, rat bone marrow cells (RBM) were used to evaluate different titanium and hydroxyapatite dental implant surfaces. The implant surfaces investigated were: a titanium surface having a porous titanium plasma-sprayed coating (sample code Ti-TPS), a titanium surface with a deep profile structure (sample code Ti-DPS), an uncoated titanium substrate with a machined surface (sample code Ti-ma) and a machined titanium substrate with a porous hydroxyapatite plasma-sprayed coating (sample code Ti-HA). RBM cells were cultured on the disc-shaped test substrates for 14 days. The culture medium was changed daily and examined for calcium and phosphate concentrations. After 14 days specimens were examined by light microscopy, scanning electron microscopy, energy dispersive X-ray analysis and morphometry of the cell-covered substrate surface. All test substrates facilitated RBM growth of extracellular matrix formation. Ti-DPS and Ti-TPS to the highest degree, followed by Ti-ma and Ti-HA. Ti-DPS and Ti-TPS displayed the highest cell density and thus seem to be well suited for the endosseous portion of dental implants. RBM cells cultured on Ti-HA showed a delayed growth pattern. This may be related to its high phosphate ion release.
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Affiliation(s)
- C Knabe
- Department of Experimental Dentistry, University Hospital Benjamin Franklin, Free University of Berlin, FRG, Germany.
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