Background: Early exploration of the semi constrained “Floating-Socket” total shoulder replacement (TSR) in 1974 led to a proliferation of various unconstrained designs that allowed resection or retention of the hum...Background: Early exploration of the semi constrained “Floating-Socket” total shoulder replacement (TSR) in 1974 led to a proliferation 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 for a resurfacing option, while severe humeral head involvement required a partial or full humeral head replacement attached to an intramedullary stem for fixation. All components evolved from cemented to cementless application by 1982. The purpose of this paper is to describe the progression of Buechel-Pappas (B-P) shoulder replacement development from the early 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of “Floating-Socket” TSR, followed by B-P stem-type, resurfacing types, bipolar-type and revision components, all of which comprise the B-P Shoulder Replacement System, were performed over a 49-year period. Results: “Floating-Socket” implants improved the results of simple, constrained ball-in-socket designs, but generally failed by glenoid component loosening in both chimpanzee and human applications. Unconstrained resurfacing-type components, both anatomical humeral head and full proximal humeral components, were quite successful, with minimal failures observed in long-term studies. Bipolar salvage implants, used for severe proximal deficiencies, revisions and massive rotator cuff arthropathy, were also very successful;providing overhead range of motion in many patients. Conclusions: Resurfacing hemiarthroplasty, in patients with intact or repairable rotator cuff mechanisms, gave the most satisfactory results and were the least technically complicated to perform, requiring minimal instrumentation. Resurfacing of full proximal humeral deficiencies, using femoral resurfacing components, gave similar clinical results to more complex semi-constrained devices, also with less technical difficulties and simple instrumentation.展开更多
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, modified...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, modified 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 fixation 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 followed for 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 grafted with homologous morselized banked bone through cortical windows in the tibia or talus. No adjuvant screw fixation was used to stabilize any metallic implant. Results: No HXLPe bearings failed in this study, and no re-revisions were performed. No primary total ankle replacement failed in this study, and there were no substantial osteolytic cysts (>2 mm) observed in primary total ankle replacements on plain X-rays. All bone grafted osteolytic cysts in revision ankle replacements remained stable, even though partial resorption of the grafted material was identified 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 be successfully bone grafted during bearing exchange revisions. Primary and revision, cementless BP metallic total ankle components have remained well-fixed to bone in the long term (greater than 20 years), without the use of adjuvant screw fixation.展开更多
文摘Background: Early exploration of the semi constrained “Floating-Socket” total shoulder replacement (TSR) in 1974 led to a proliferation 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 for a resurfacing option, while severe humeral head involvement required a partial or full humeral head replacement attached to an intramedullary stem for fixation. All components evolved from cemented to cementless application by 1982. The purpose of this paper is to describe the progression of Buechel-Pappas (B-P) shoulder replacement development from the early 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of “Floating-Socket” TSR, followed by B-P stem-type, resurfacing types, bipolar-type and revision components, all of which comprise the B-P Shoulder Replacement System, were performed over a 49-year period. Results: “Floating-Socket” implants improved the results of simple, constrained ball-in-socket designs, but generally failed by glenoid component loosening in both chimpanzee and human applications. Unconstrained resurfacing-type components, both anatomical humeral head and full proximal humeral components, were quite successful, with minimal failures observed in long-term studies. Bipolar salvage implants, used for severe proximal deficiencies, revisions and massive rotator cuff arthropathy, were also very successful;providing overhead range of motion in many patients. Conclusions: Resurfacing hemiarthroplasty, in patients with intact or repairable rotator cuff mechanisms, gave the most satisfactory results and were the least technically complicated to perform, requiring minimal instrumentation. Resurfacing of full proximal humeral deficiencies, using femoral resurfacing components, gave similar clinical results to more complex semi-constrained devices, also with less technical difficulties and simple instrumentation.
文摘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, modified 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 fixation 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 followed for 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 grafted with homologous morselized banked bone through cortical windows in the tibia or talus. No adjuvant screw fixation was used to stabilize any metallic implant. Results: No HXLPe bearings failed in this study, and no re-revisions were performed. No primary total ankle replacement failed in this study, and there were no substantial osteolytic cysts (>2 mm) observed in primary total ankle replacements on plain X-rays. All bone grafted osteolytic cysts in revision ankle replacements remained stable, even though partial resorption of the grafted material was identified 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 be successfully bone grafted during bearing exchange revisions. Primary and revision, cementless BP metallic total ankle components have remained well-fixed to bone in the long term (greater than 20 years), without the use of adjuvant screw fixation.