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Open Journal of.Orthopedics 2024年第8期14卷 374-379页

作者： frederick f. buechel sr frederick f. buechel Jr Rutgers New Jersey Medical School Department of Orthopaedic Surgery Newark USA Lenox Hill Hospital Department of Orthopaedic Surgery New York USA

Background: Sagittal plane placement of.the tibial component in total knee replacement (TKR) has important implications f.r maximizing the range of.f.exion motion, allowing collateral ligaments to f.nction more normally, as well as providing ideal compressive loading on the tibial bone-prosthesis interf.ce. This study attempts to quantif. the normal posterior tibial slope (PTS) angle pre-operatively and post-operatively in osteoarthritic patients af.er using a conventional extramedullary tibial resection guide to assess its ef.ectiveness. Methods: f.rty-nine primary cementless total knee replacements in 34 osteoarthritic patients were measured radiographically pre-operatively and one year post-operatively to determine the PTS and its ef.ect on range of.motion. Lateral X-rays, using the anterior cortical line of.the tibia, were employed f.r all measurements. Results: Pre-operative PTS measured 11.83˚ (range 5˚ - 18˚), while post-operative PTS of.implanted tibial components measured 11.30o (range 4˚ - 18˚). The pre-operative range of.motion of.112˚ (range 30˚ to 135˚) was improved to 119˚ (range 90˚ to 135˚) post-operatively af.er 1 year. Conclusions: Anterior tibial shaf. ref.rencing using a conventional extramedullary tibial resection guide provides an easy and convenient method f.r reproducing the anatomical PTS during TKR. This methodology provided improvement in average range of.motion f.om 112˚ pre-operatively to 119˚ post-operatively at one year.

关键词： Posterior Tibial Slope Posterior Tibial Inclination Extramedullary Tibial Resection Guide Total Knee Alignment

Cementless buechel-Pappas Resurf.cing Total Hip Replacement: A 45-Year Personal Journey to Overcome Wear, Osteolysis, Loosening and f.moral Neck f.actures

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Open Journal of.Orthopedics 2023年第10期13卷 435-442页

作者： frederick f. buechel sr Rutgers NJ Medical School Newark USA South Mountain Orthopaedic Associates South Orange USA

Background: Resurf.cing-type total hip replacement (THR) has been successf.lly developed over the past 50 years through collaborative ef.orts between engineers and surgeons. Much of.the development was pursued by individuals or groups, each of.which participated in adding f.rther ref.nements to the implants, instruments and surgical procedures, thus minimizing the serious problems of.wear, osteolysis, loosening and f.moral neck f.actures. The purpose of.this study is to explore the development process to optimize the resurf.cing total hip replacement into its current application. Methods: In the early 1980s, cementless resurf.cing implants were developed using “thin shell” technology to minimize bony resection of.the acetabulum and f.moral head. f.moral components utilized short, non-porous coated, tapered straight stems to reduce shear stresses in the f.moral neck to prevent f.actures and stress shielding, while mechanically stabilizing and aligning the components. Acetabular components were anatomically designed to be recessed inside bony borders to avoid neck-cup impingement and loosening. Initially, ultrahigh molecular weight polyethylene (UHMWPE) was used as a bearing, but due to high levels of.wear and osteolysis, it was replaced by wear-resistant highly crossed-linked polyethylene (HXLPE) in 2008. Results: Use of.HXLPE as a bearing material in both Co-Cr-Mo and titanium nitride (TiN) ceramic-coated resurf.cing implants has led to excellent patient outcomes f.r more than 10 years. In clinical studies, 87% of.patients with bilateral total hip replacements pref.r their resurf.cing-type total hip over their stem-type total hip. The author’s own personal resurf.cing total hips, now at 8 and 5 years, respectively, provide “normal” f.nction and no radiographic osteolysis. Conclusions: Af.er 45 years of.active evaluation, including mechanical design considerations, prosthetic design development, clinical and radiographic analysis of.results, as well as availability o

关键词： Resurf.cing Total Hip Replacement

Cementless Semi-Constrained Rotating Platf.rm Total Knee Replacement: A Concise f.llow-Up of.a Previous Report at a Minimum of.Twenty Years

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Open Journal of.Orthopedics 2023年第3期13卷 71-77页

作者： frederick f. buechel sr. frederick f. buechel Jr. Thomas E. Helbig Rutgers NJ Medical School Newark USA South Mountain Orthopaedic Associates South Orange USA Lenox Hill Hospital New York USA

Background: A previous report evaluated the initial 310 cementless, buechel-Pappas (B-P), Semi-Constrained Rotating Platf.rm total knee replacements in 257 patients f.llowed f.r an average of.7.6 years, range 2 - 18 years. Diagnoses were osteoarthritis in 233 patients, post traumatic arthritis in 4 patients and rheumatoid arthritis in 22 patients. Knee Scores, using a strict knee scoring scale were 86.4% excellent, 12.3% good, 0.3% f.ir and 1.0% poor results. Survivorship, using an end point of.revision f.r any mechanical reason (including component loosening, bearing wear and bearing dislocation) was 99.4%. Survivorship f.r a poor knee score (including persistent pain, loosening, instability and inf.ction was 97.6%. The purpose of.the present study is to report the updated results of.this same patient cohort at a minimum f.llow-up of.twenty years. Methods: The average age of.patients at the time of.surgery was 67 years, range 34 to 91 years. A total of.20 patients (22 knees) were still living, with a f.llow-up of.20 - 30 years (mean 23.47 years). The same strict knee scoring scale and survivorship analysis were used to evaluate patient outcomes at the 20 to 30 years interval. Results: Survivorship, in the current study, using the same end points as in the previous study, was 96.5% at the 20 and 30-year intervals. Late mechanical f.ilure and osteolysis were not identif.ed. Conclusion: This cementless, semi-constrained rotating platf.rm total knee replacement has stood the test of.time f.r more than 20 years and can be considered acceptable f.r long-term use, in properly selected patients.

关键词： Knee Replacement Cementless Semi-Constrained Rotating

buechel Pappas Resurf.cing Shoulder Replacement: Evolution and over 40 Years of.Clinical Experience

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Open Journal of.Orthopedics 2024年第5期14卷 218-228页

作者： frederick f. buechel Michael J. Pappas Rutgers NJ Medical School Newark NJ USA South Mountain Orthopaedic Associates South Orange NJ USA New Jersey Institute of.Technology Newark NJ USA

Background: Early exploration of.the semi constrained “f.oating-Socket” total shoulder replacement (Tsr) in 1974 led to a prolif.ration of.various unconstrained designs that allowed resection or retention of.the humeral head, depending upon the pathological process involved. Degenerative glenohumeral arthritis with mild to moderate involvement of.subchondral bone allowed f.r a resurf.cing option, while severe humeral head involvement required a partial or f.ll humeral head replacement attached to an intramedullary stem f.r f.xation. All components evolved f.om cemented to cementless application by 1982. The purpose of.this paper is to describe the progression of.buechel-Pappas (B-P) shoulder replacement development f.om the early 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of.“f.oating-Socket” Tsr, f.llowed by B-P stem-type, resurf.cing types, bipolar-type and revision components, all of.which comprise the B-P Shoulder Replacement System, were perf.rmed over a 49-year period. Results: “f.oating-Socket” implants improved the results of.simple, constrained ball-in-socket designs, but generally f.iled by glenoid component loosening in both chimpanzee and human applications. Unconstrained resurf.cing-type components, both anatomical humeral head and f.ll proximal humeral components, were quite successf.l, with minimal f.ilures observed in long-term studies. Bipolar salvage implants, used f.r severe proximal def.ciencies, revisions and massive rotator cuf. arthropathy, were also very successf.l;providing overhead range of.motion in many patients. Conclusions: Resurf.cing hemiarthroplasty, in patients with intact or repairable rotator cuf. mechanisms, gave the most satisf.ctory results and were the least technically complicated to perf.rm, requiring minimal instrumentation. Resurf.cing of.f.ll proximal humeral def.ciencies, using f.moral resurf.cing components, gave similar clinical results to more complex semi-constrained devices,

关键词： Total Shoulder Replacement Resurf.cing Shoulder Replacement

buechel-Pappas Total Ankle Replacement: Use of.Highly Cross-Linked Polyethylene Meniscal Bearings over a 13 - 15 Year Interval

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Open Journal of.Orthopedics 2023年第8期13卷 321-327页

作者： frederick f. buechel Michael J. Pappas Rutgers NJ Medical School Newark USA South Mountain Orthopaedic Associates South Orange USA Mechanical Engineering NJ Institute of Technology Newark USA

Background: The buechel-Pappas (BP) meniscal bearing total ankle replace-ment was initially developed as a “shallow-sulcus” talar component device using cobalt-chromium-molybdenum alloy, in 1978, and later, modif.ed to a “deep-sulcus” talar component device using titanium nitride (TiN) ceramic and porous coating in 1989. Wear related osteolytic cysts were noted in the tibia and talus surrounding these devices that compromised long term f.xation and stability when using standard ultra-high molecular weight polyethylene (UHMWPe) as a bearing material. This study explores the use of.highly cross-linked UHMWPe (HXLPe) to minimize osteolysis by replacing standard UHMWPe with this more wear-resistant material. Methods: There were 12 primary and 8 revision total ankle replacements f.llowed f.r 13 to 15 years. HXLPe was used in all meniscal bearings, either as primary or revision implants. All stable metallic tibial and talar components were retained in revision cases. Osteolytic cysts greater than 10 mm in diameter were bone graf.ed with homologous morselized banked bone through cortical windows in the tibia or talus. No adjuvant screw f.xation was used to stabilize any metallic implant. Results: No HXLPe bearings f.iled in this study, and no re-revisions were perf.rmed. No primary total ankle replacement f.iled in this study, and there were no substantial osteolytic cysts (>2 mm) observed in primary total ankle replacements on plain X-rays. All bone graf.ed osteolytic cysts in revision ankle replacements remained stable, even though partial resorption of.the graf.ed material was identif.ed in most of.the ankles. No loosening of.porous coated and TiN coated tibial and talar components were seen;the longest surviving metal components in the revision group was 24 years with the revised bearing at 15 years. Conclusions: HXLPe has greatly improved wear resistance in meniscal-bearing BP total ankle replacements in both primary and revision arthroplasties. Osteolytic cysts can b

关键词： Cementless Total Ankle Replacement Meniscal Ankle Replacement Osteolysis Bone Graf. of.Cysts

f.rmation of.tholeiitic basalts by lithosphere-asthenosphere interaction: example f.om Datong, North China

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Formation of tholeiitic basalts by lithosphere-asthenosphere...

Cu-Bearing Mokama Granite Prospect of.the Kibara Belt in the Maniema Province, DRC: A Preliminary Petrography, Geochemistry, and f.uid Inclusion Study

2006年全国岩石学与地球动力学研讨会

作者： frederick A．f.ey Mark D．f.igenson Department of.Earth Atmospheric and Planetary Sciences MITCambridge MA 02139 Department of.Geological Sciences Rutgers University 610 Taylor RoadPiscatawayNJ08854USA

The geochemistry of.Quaternary volcanic rocks f.om Datong provides important constraints on the petrogenesis of.continental alkali and tholeiitic basalts and lithospheric evolution in the western North China Craton. Alkali basalts in north Datong have trace element compositions similar to oceanic island basalts (OIB) . They show nearly homogenous isotopic compositions ( ε Nd=5.4-6.8 and 87sr/86 sr=0.7035-0.7037) that resemble the nearby Hannuoba Miocene basalts,

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Open Journal of.Geology 2023年第10期13卷 1007-1023页

作者： Douxdoux Kumakele Makutu Ivan Bongwe Chris Musomo Mf.mu frederick Makoka Mwanza Jean-Pierre Bulambo Pierre Kambuli Kaseti Energy Resource Department College of Engineering Inha University Incheon Republic of Korea Department of.Geosciences Kinshasa University Kinshasa Democratic Republic of the Congo Department of.Geology University of Lubumbashi Lubumbashi Democratic Republic of the Congo

The Mokama granites are located in the Kibara belt (KIB) and hosts tin oxide group minerals (TOGM: Sn-W), and sulf.de group minerals (SGM: Cu-Zn-f.-As). The essential of.Cu mineralization (non-economic deposit) is disseminated inside the rock and consists of.minerals (Raman, EPMA and metallographic microscopy) including chalcopyrite and bornite that are replaced by chalcocite and covellite, and the last also replaced later by malachite. The chemistry (XRf. LA-ICP-MS) of.these peraluminous S-type leucogranites show SiO2 (71 wt% - 79 wt%), ASI (1.4 - 3.1 molar), and are enriched in Rb (681 - 1000 ppm), Ta (12–151 ppm), Sn (43 - 142 ppm), Cu (10 - 4300 ppm), Zn (60 - 740 ppm), U (2.2 - 20.7 ppm) while depleted in Zr (20 - 31 ppm), sr (20 - 69 ppm), Hf.(1.3 - 2.0 ppm), Th (2.2 - 18.9 ppm), W (9 - 113 ppm), Pb (5 - 50 ppm), Ge (5 - 10 ppm), Cs (21 - 53 ppm) and Bi (0.6 - 17.4 ppm) and low ratios of.(La/Yb) N, (Gd/Yb) N, (La/Sm) N). f.uid inclusion assemblages (f.As) hosted in quartz in the Mokama granites show ranges of.salinities of.4 - 23 wt% (NaCl equivalent) and homogenization temperatures (Th) of.190°C - 550°C. A boiling assemblage in the granite suggests a f.uid phase separation occurred at about 380 - 610 bars, and this corresponds to apparent paleodepths of.approximately 1 - 2 km (lithostatic model) or 3 - 5 km (hydrostatic model). f.As hosted in TOGM such as cassiterite (salinities of.2 wt% - 10 wt% and Th of.220°C - 340°C) helped set up the possible temperature limit of.SGM (Cu sulf.de) precipitations that are estimated below 200°C.

关键词： Mokama Granites Petrography Geochemistry Cu-Mineralization XRf EPMA LA-ICP-MS f.uid Inclusion Microthermometry