Transcatheter aortic valve replacement in low-risk young population:A double edge sword?

Since the advent of transcatheter aortic valve replacement(TAVR)in 2002,it has now become the default interventional strategy for symptomatic patients presenting with severe aortic stenosis,particularly in intermediate to highsurgical risk patients.In 2019,the United States Food and Drug Administration approved TAVR in low-risk patients based on two randomized trials.However,these breakthrough trials excluded patients with certain unfavorable anatomies and odd profiles.While currently there is no randomized study of TAVR in young patients,it may be preferred by the young population given the benefits of early discharge,shorter hospital stay,and expedite recovery.Nonetheless,it is important to ruminate various factors including lifetime expectancy,risk of pacemaker implantation,and the need for future valve or coronary interventions in young cohorts before considering TAVR in these patients.Furthermore,the data on long-term durability(>10 years)of TAVR is still unknown given most of the procedures were initially performed in the high or prohibitive surgical risk population.Thus,this editorial aims to highlight the importance of considering an individualized approach in young patients with consideration of various factors including lifetime expectancy while choosing TAVR against surgical aortic valve replacement.

Meta-analysis of new intervention measures for preventing side effects of artificial joint replacement

BACKGROUND Intertrochanteric fracture of the femur occurs mostly among older people,and seriously affects daily life and quality of life.At present,physical intervention,drug treatment,routine intervention and rehabilitation training are widely used for prevention of side effects,but it is still inconclusive which intervention has the best effect.AIM To compare the effects of new intervention measures for preventing side effects of artificial joint replacement.METHODS We searched the Chinese and English literatures for comparative studies on the prevention of side effects of new interventions for artificial joint replacement from July 2013 to June 2023 in China HowNet,PubMed,Wanfang,Weipu and other databases.Study quality was evaluated by improved Jadad scoring standard,and the effects of different interventions on preventing different complications were analyzed by meta-analysis of evidence-based medicine with Review Manager 5.0 software.RESULTS Ten articles,including 869 cases,were finally included.The preventive effects of different interventions on the side effects of artificial joint replacement were studied,and valid data were extracted.There were two articles on the preventive effects of drug intervention,four on comparison of the preventive effects of combined and single interventions,and three on the preventive effects of physical intervention,rehabilitation training and routine intervention.Meta-analysis showed that the preventive effect of rivaroxaban was significantly better than low molecular weight heparin calcium[mean difference(MD)=-0.16,95%CI:-0.28 to-0.04,P<0.05].The effect of combined intervention was significantly better than that of single intervention(MD=-0.08,95%CI:-0.16 to-0.01,P<0.001).Physical intervention was significantly better than routine intervention and rehabilitation training(MD=0.26,95%CI:0.16–0.36,P<0.001).CONCLUSION Rivaroxaban combined with rehabilitation training is preferred for preventing deep vein thrombosis after artificial joint replacement.In the prevention of pulmonary embolism,rivaroxaban drug intervention is given priority.The effect of combined intervention is better than that of single intervention.

Bilateral pericapsular end nerve blocks for steroid-induced avascular necrosis following COVID-19 infection requiring bilateral total hip replacement

BACKGROUND Osteonecrosis or avascular necrosis(AVN)of the hip was one of the dreaded complications of coronavirus disease 2019(COVID-19),which emerged in patients who received steroid therapy.Corticosteroids have been a mainstay in the treatment protocol of COVID-19 patients.Popular corticosteroid drugs used in patients suffering from COVID-19 were intravenous(IV)or oral dexamethasone,methylprednisolone or hydrocortisone.The use of such high doses of corticost-eroids has shown very positive results and has been lifesaving in many cases.Still,long-term consequences were drug-induced diabetes,osteoporosis,Cushing syndrome,muscle wasting,peripheral fat mobilization,AVN,hirsutism,sleep disturbances and poor wound healing.A significant number of young patients were admitted for bilateral total hip replacements(THR)secondary to AVN following steroid use for COVID-19 treatment.AIM To assess the efficacy of bilateral pericapsular end nerve group(PENG)blocks in patients posted for bilateral THR post-steroid therapy after COVID-19 infection and assess the time taken to first ambulate after surgery.METHODS This prospective observational study was conducted between January 2023 and August 2023 at Care Hospitals,Hyderabad,India.Twenty young patients 30-35 years of age who underwent bilateral THR were studied after due consent over 8 months.All the patients received spinal anaesthesia for surgery and bilateral PENG blocks for postoperative analgesia.RESULTS The duration of surgery was 2.5 h on average.Seventeen out of twenty patients(85%)had a Visual Analog Score(VAS)of less than 2 and did not require any supplementation.One patient was removed from the study,as he required re-exploration.The remaining two patients had a VAS of more than 8 and received IV morphine post-operatively as a rescue analgesic drug.Fifteen out of seventeen patients(88.2%)could be mobilized 12 h after the procedure.CONCLUSION Osteonecrosis or AVN of the hip was one of the dreaded complications of COVID-19,which surfaced in patients who received steroid therapy requiring surgical intervention.Bilateral PENG block is an effective technique to provide post-operative analgesia resulting in early mobilization and enhanced recovery after surgery.

Generation of mitochondrial replacement monkeys by female pronucleus transfer

Mutations in mitochondrial DNA(mtDNA)are maternally inherited and have the potential to cause severe disorders.Mitochondrial replacement therapies,including spindle,polar body,and pronuclear transfers,are promising strategies for preventing the hereditary transmission of mtDNA diseases.While pronuclear transfer has been used to generate mitochondrial replacement mouse models and human embryos,its application in non-human primates has not been previously reported.In this study,we successfully generated four healthy cynomolgus monkeys(Macaca fascicularis)via female pronuclear transfer.These individuals all survived for more than two years and exhibited minimal mtDNA carryover(3.8%–6.7%),as well as relatively stable mtDNA heteroplasmy dynamics during development.The successful establishment of this nonhuman primate model highlights the considerable potential of pronuclear transfer in reducing the risk of inherited mtDNA diseases and provides a valuable preclinical research model for advancing mitochondrial replacement therapies in humans.

Buechel Pappas Resurfacing Shoulder Replacement: Evolution and over 40 Years of Clinical Experience

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.

Efficient cache replacement framework based on access hotness for spacecraft processors

A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity of contemporary high-performance spacecraft processors.To harness these non-uniform access behaviors,an efficient cache replacement framework featuring an auxiliary cache specifically designed to retain evicted hot data was proposed.This framework reconstructs the cache replacement policy,facilitating data migration between the main cache and the auxiliary cache.Unlike traditional cacheline-granularity policies,the approach excels at identifying and evicting infrequently used data,thereby optimizing cache utilization.The evaluation shows impressive performance improvement,especially on workloads with irregular access patterns.Benefiting from fine granularity,the proposal achieves superior storage efficiency compared with commonly used cache management schemes,providing a potential optimization opportunity for modern resource-constrained processors,such as spacecraft processors.Furthermore,the framework complements existing modern cache replacement policies and can be seamlessly integrated with minimal modifications,enhancing their overall efficacy.

Risk of permanent pacemaker implantation following transcatheter aortic valve replacement:Which factors are most relevant?

Transcatheter aortic valve replacement(TAVR)has emerged as a formidable treatment option for severe symptomatic aortic stenosis ahead of surgical aortic valve replacement.The encouraging results from large randomized controlled trials has resulted in an exponential rise in the use of TAVR even in the low-risk patients.However,this is not without challenges.Need for permanent pacemaker(PPM)post-TAVR remains the most frequent and clinically relevant challenge.Naturally,identifying risk factors which predispose an individual to develop high grade conduction block post-TAVR is important.Various demographic factors,electrocardiographic features,anatomic factors and procedural characteristics have all been linked to the development of advanced conduction block and need for PPM following TAVR.Amongst these electrophysiological variables,most notably a prolonged QRS>120 ms regardless of the type of conduction block seems to be one of the strongest predictors on logistic regression models.The index study by Nwaedozie et al highlights that patients requiring PPM post-TAVR had higher odds of having a baseline QRS>120 ms and were more likely to be having diabetes mellitus that those who did not require PPM.

Robotics in total knee replacement:Current use and future implications

Robotic total knee replacement(TKR)surgery has evolved over the years with the aim of improving the overall 80% satisfaction rate associated with TKR surgery.Proponents claim higher precision in executing the pre-operative plan which results in improved alignment and possibly better clinical outcomes.Opponents suggest longer operative times with potentially higher complications and no superiority in clinical outcomes alongside increased costs.This editorial will summarize where we currently stand and the future implications of using robotics in knee replacement surgery.

Current knowledge for the risk factors of early permanent pacemaker implantation following transcatheter aortic valve replacement and what is next for the primary prevention?

In this editorial,we comprehensively summarized the preoperative risk factors of early permanent pacemaker implantation after transcatheter aortic valve replacement(TAVR)among patients with severe aortic stenosis from several renowned clinical studies and focused on the primary prevention of managing the modifiable factors,e.g.,paroxysmal atrial fibrillation before the TAVR.

Effect of the Initial Vortex Structure on Intensity Change During Eyewall Replacement Cycle of Tropical Cyclones:A Numerical Study

This study investigates the effect of the initial tropical cyclone(TC)vortex structure on the intensity change during the eyewall replacement cycle(ERC)of TCs based on two idealized simulations using the Weather Research and Forecasting(WRF)model.Results show that an initially smaller TC with weaker outer winds experienced a much more drastic intensity change during the ERC than an initially larger TC with stronger outer winds.It is found that an initially larger TC vortex with stronger outer winds favored the development of more active spiral rainbands outside the outer eyewall,which slowed down the contraction and intensification of the outer eyewall and thus prolonged the duration of the concentric eyewall and slow intensity evolution.In contrast,the initially smaller TC with weaker outer winds corresponded to higher inertial stability in the inner core and weaker inertial stability but stronger filamentation outside the outer eyewall.These led to stronger boundary layer inflow,stronger updraft and convection in the outer eyewall,and suppressed convective activity outside the outer eyewall.These resulted in the rapid weakening during the formation of the outer eyewall,followed by a rapid re-intensification of the TC during the ERC.Our study demonstrates that accurate initialization of the TC structure in numerical models is crucial for predicting changes in TC intensity during the ERC.Additionally,monitoring the activity of spiral rainbands outside the outer eyewall can help to improve short-term intensity forecasts for TCs experiencing ERCs.

Pacemaker post transcatheter aortic valve replacement:A multifactorial risk?

Pacemaker post-transcatheter aortic valve replacement is related to multifactorial risk.Nwaedozie et al brought to the body of evidence electrocardiogram and clinical findings.However,procedural characteristics have at least as much impact on the final need for a permanent pacemaker and potentially on the pacing rate.In this regard,long-term follow-up and understanding of the impact of long-term stimulation is of utmost importance.

Does the use of double hormone replacement therapy for trauma patient organ donors improve organ recovery for transplant

BACKGROUND With an ongoing demand for transplantable organs,optimization of donor management protocols,specifically in trauma populations,is important for obta-ining a high yield of viable organs per patient.Endocrine management of brain-dead potential organ donors(BPODs)is controversial,leading to heterogeneous clinical management approaches.Previous studies have shown that when levo-thyroxine was combined with other treatments,including steroids,vasopressin,and insulin,BPODs had better organ recovery and survival outcomes were increased for transplant recipients.AIM To determine if levothyroxine use in combination with steroids in BPODs increased the number of organs donated in trauma patients.METHODS A retrospective review of adult BPODs from a single level 1 trauma center over ten years was performed.Exclusion criteria included patients who were not solid organ donors,patients who were not declared brain dead(donation after circulatory death),and patients who did not receive steroids in their hospital course.Levothyroxine and steroid administration,the number of organs donated,the types of organs donated,and demographic information were recorded.Univariate analyses were performed with P<0.05 considered to be statistically significant.RESULTS A total of 88 patients met inclusion criteria,69(78%)of whom received levothyroxine and steroids(ST/LT group)vs 19(22%)receiving steroids without levothyroxine(ST group).No differences were observed between the groups for gender,race,pertinent injury factors,age,or other hormone therapies used(P>0.05).In the ST/LT group,68.1%(n=47)donated a high yield(3-5)of organ types per donor compared to 42.1%(n=8)in the ST group(P=0.038).There was no difference in the total number of organ types donated between the groups(P=0.068).CONCLUSION This study suggests that combining levothyroxine and steroid administration increases high-yield organ donation per donor in BPODs in the trauma patient population.Limitations to this study include the retrospective design and the relatively small number of organ donors who met inclusion criteria.This study is unique in that it mitigates steroid administration as a confounding variable and focuses specifically on the adjunctive use of levothyroxine.

Short-term outcome of total knee replacement in a patient with hemophilia:A case report and review of literature

BACKGROUND Hemophilia A is a rare inherited bleeding disorder caused by mutations in the factor Ⅷ gene. This clotting factor plays an intrinsic role in the blood coagulation pathway. Patients with hemophilia may develop orthopedic manifestations such as hemarthrosis, but multiple malunion of fractures over the knee is rare and difficult to treat.CASE SUMMARY We report a patient with hemophilia A who developed severe knee osteoarthritis along with fracture malunion and nonunion. Total knee replacement was performed using a custom-made modular hinged knee prosthesis(cemented) equipped with extended distal and proximal stems. At 3 years’ follow-up, the patient exhibited excellent clinical function and remained satisfied with the surgical outcome. Surgical intervention was accompanied by rigorous coagulation factor replacement.CONCLUSION This case highlights various unique scenarios specific to individuals with hemophilia and fracture deformity.

Advances in Cervical Artificial Disc Replacement for Cervical Spondylosis

Anterior cervical decompression and fusion(ACDF)treatment for cervical spondylosis has been more than half a century,and achieved good clinical results.However,with the continuous extension of follow-up time,the fusion segment-associated postoperative complications emerged gradually.Reserved cervical stability and activity,the concept of non-fusion was born.As a non-fusion technique,cervical artificial disc replacement(CADR)developed rapidly.With the continuous development of artificial prosthesis materials and design concepts,and specification and proficiency of surgical procedures,CADR has achieved better short and mid-term clinical efficacy than ACDF.Compared with ACDF,the main advantages of CADR are that the postoperative recovery is quick,the activity and stability of cervical vertebra are maintained,the height of cervical intervertebral space is restored,and the stress of adjacent segments and the rate of surgical renovation are reduced.In clinical work,as an emerging technology,CADR requires spine surgeons to control the surgical indications,contraindications,and patients'conditions strictly.This article reviews the research progress of CADR in order to provide new ideas for clinical treatment of cervical spondylosis.

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

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.

Eff ects of continuous renal replacement therapy on infl ammation-related anemia, iron metabolism and prognosis in sepsis patients with acute kidney injury

BACKGROUND:This study aims to evaluate the eff ect of continuous renal replacement therapy(CRRT)on inflammation-related anemia,iron metabolism,and the prognosis in sepsis patients with acute kidney injury(AKI).METHODS:Sepsis patients with AKI were prospectively enrolled and randomized into the CRRT and control groups.The clinical and laboratory data on days 1,3 and 7 after intensive care unit(ICU)admission were collected.The serum interleukin(IL)-6,hepcidin,erythropoietin,ferritin,and soluble transferrin receptor(sTfR)were determined by enzyme-linked immunosorbent assay.The Sequential Organ Failure Assessment(SOFA)score and 28-day mortality were recorded.Data were analyzed using Pearson’s Chi-square test or Fisher’s exact test(categorical variables),and Mann-Whitney U-test or t-test(continuous variables).RESULTS:The hemoglobin and serum erythropoietin levels did not signifi cantly diff er between the CRRT and control groups though gradually decreased within the first week of ICU admission.On days 3 and 7,the serum IL-6,hepcidin,ferritin,and red blood cell distribution width significantly decreased in the CRRT group compared to the control group(all P<0.05).On day 7,the serum iron was significantly elevated in the CRRT group compared to the control group(P<0.05).However,the serum sTfR did not signifi cantly diff er between the groups over time.In addition,the SOFA scores were signifi cantly lower in the CRRT group compared to the control group on day 7.The 28-day mortality did not signifi cantly diff er between the control and CRRT groups(38.0%vs.28.2%,P=0.332).CONCLUSION:CRRT might have beneficial effects on the improvement in inflammationrelated iron metabolism and disease severity during the fi rst week of ICU admission but not anemia and 28-day mortality in sepsis patients with AKI.

Cementless Semi-Constrained Rotating Platform Total Knee Replacement: A Concise Follow-Up of a Previous Report at a Minimum of Twenty Years

Background: A previous report evaluated the initial 310 cementless, Buechel-Pappas (B-P), Semi-Constrained Rotating Platform total knee replacements in 257 patients followed for 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% fair and 1.0% poor results. Survivorship, using an end point of revision for any mechanical reason (including component loosening, bearing wear and bearing dislocation) was 99.4%. Survivorship for a poor knee score (including persistent pain, loosening, instability and infection was 97.6%. The purpose of the present study is to report the updated results of this same patient cohort at a minimum follow-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 follow-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 failure and osteolysis were not identified. Conclusion: This cementless, semi-constrained rotating platform total knee replacement has stood the test of time for more than 20 years and can be considered acceptable for long-term use, in properly selected patients.

Dexmedetomidine-induced anesthesia in elderly patients undergoing hip replacement surgery

BACKGROUND A femoral neck fracture is a common and frequently reported issue in orthopedics, with a greater rate of incidence among the elderly. Due to their advanced age and the presence of some primary diseases, both anesthesia and surgery are increasingly difficult in elderly patients with a femoral neck fractures. In fact,general anesthesia can easily induce complications such as cognitive dysfunction,which is not conducive to postoperative recovery.AIM To analyze the efficacy of dexmedetomidine in inducing anesthesia for elderly patients undergoing hip replacement surgery.METHODS A total of 98 elderly patients undergoing hip replacement in our hospital from June 2020 to June 2021 were randomly divided into control group(49 cases) and observation group(49 cases). The control group was given general anesthesia, and the observation group was combined with dexmedetomidine for anesthesia on the basis of the control group. Both groups were observed until the patients were discharged. The vital signs, serum inflammatory factors and renal function indexes of the two groups were compared before, during and 6 h after operation.The postoperative recovery and adverse events of the two groups were statistically analyzed.RESULTS Compared with the mean arterial pressure of the two groups, the intraoperative and postoperative 6 h was higher than that before the operation, the intraoperative was lower than the postoperative 6 h(P < 0.05);the blood oxygen saturation of the two groups was higher than that before operation and 6 h after operation, and the observation group was higher than the control group 6 h after operation(P < 0.05). The heart rate of the two groups was lower during and 6 h after operation than that before operation, and higher at 6 h after operation than that during operation(P < 0.05).The levels of serum C-reactive protein, tumor necrosis factor-α, interleukin-1β and kidney injury molecule-1 in the two groups were higher during operation and 6 h after operation than those before operation(P < 0.05). The level of serum urea nitrogen in the two groups was higher than that before operation, and that in the observation group was lower than that in the control group(P < 0.05). During hospitalization, the first time of getting out of bed, recovery time of grade Ⅱ muscle strength, recovery time of grade Ⅲ muscle strength and hospitalization time in the observation group were shorter than those in the control group(P < 0.05).CONCLUSION Dexmedetomidine can effectively improve the vital signs of elderly patients undergoing hip replacement surgery, reduce the body’s inflammatory response and renal function damage, and promote postoperative recovery. Meanwhile, dexmedetomidine showcased a good safety profile and a good anesthetic outcome.

Delayed Coronary Ostial Stenosis after Surgical Aortic Valve Replacement and Root Enlargement Treated with Beating Heart On-Pump CABG

Coronary ostial stenosis after surgical aortic valve replacement (SAVR) is a rare but potentially fatal complication. Surgeons must have a high level of vigilance regarding the presentation of acute myocardial ischemia, arrhythmia, and heart failure after AVR. According to most reports, this event can be time-dependent divided into two groups;early acute phase that mostly happens intraoperative during weaning of CPB or in early ICU stay, and late presentation usually appears 1 - 6 months post surgery. Here, we describe an unusual subacute presentation of right coronary ostial stenosis 12 days after SAVR, which was treated successfully with redo beating heart coronary artery bypass grafting (CABG).

Cementless Buechel-Pappas Resurfacing Total Hip Replacement: A 45-Year Personal Journey to Overcome Wear, Osteolysis, Loosening and Femoral Neck Fractures

Background: Resurfacing-type total hip replacement (THR) has been successfully developed over the past 50 years through collaborative efforts between engineers and surgeons. Much of the development was pursued by individuals or groups, each of which participated in adding further refinements to the implants, instruments and surgical procedures, thus minimizing the serious problems of wear, osteolysis, loosening and femoral neck fractures. The purpose of this study is to explore the development process to optimize the resurfacing total hip replacement into its current application. Methods: In the early 1980s, cementless resurfacing implants were developed using “thin shell” technology to minimize bony resection of the acetabulum and femoral head. Femoral components utilized short, non-porous coated, tapered straight stems to reduce shear stresses in the femoral neck to prevent fractures 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 resurfacing implants has led to excellent patient outcomes for more than 10 years. In clinical studies, 87% of patients with bilateral total hip replacements prefer their resurfacing-type total hip over their stem-type total hip. The author’s own personal resurfacing total hips, now at 8 and 5 years, respectively, provide “normal” function and no radiographic osteolysis. Conclusions: After 45 years of active evaluation, including mechanical design considerations, prosthetic design development, clinical and radiographic analysis of results, as well as availability of components cleared by the FDA 510 K process, the author has stated a personal preference for the BP Resurfacing Hip System. His excellent mid-term results in both of his resurfaced hips are similar to the long-term results presented in published studies.