Graph Theory and Matrix Approach(GTMA)Model for the Selec­tion of the Femoral-Component of Total Knee Joint Replacement

Total Knee Replacement(TKR)is the increasing trend now a day,in revision surgery which is associated with aseptic loosening,which is a challenging research for the TKR component.The selection of optimal material loosening can be controlled at some limits.This paper is going to consider the best material selected among a number of alternative materials for the femoral component(FC)by using Graph Theory.Here GTMA process used for optimization of material and a systematic technique introduced through sensitivity analysis to find out the more reliable result.Obtained ranking suggests the use of optimized material over the other existing material.By following GTMA Co_Cr-alloys(wrought-Co-Ni-Cr-Mo)and Co_Cr-alloys(cast-able-Co-Cr-Mo)are on the 1st and 2nd position respectively.

Effect of fast track surgery care on knee joint function in patients with knee joint replacement surgery: A systematic review

目的:系统评价加速康复外科护理对膝关节置换术患者膝关节功能的影响。方法:计算机检索电子数据库TheCochraneLibrary、PubMed、EBSCO、CINAHL、知网、万方、维普及中国生物医学数据库,获取国内外关于加速康复外科护理在膝关节置换术中应用的随机对照试验,由2人根据纳入排除标准独立筛选文献并提取数据,采用RevMan5.3对纳入研究进行Meta分析。结果:共纳入8篇RCT文献,共计患者635例。Meta分析结果显示:(1)与常规护理相比,加速康复外科护理能提高膝关节置换患者特种外科医院膝关节评分,根据资料收集时间的不同,对膝关节特殊手术医院评分进行亚组分析,结果显示:加速康复外科护理提高膝关节置换患者术后2个月、3个月、6个月、1年的膝关节特殊手术医院评分[2个月:加权均数差(WMD)=15.20,95%CI:13.58-16.82,P<0.01;3个月:WMD=9.42,95%CI:7.80-11.04,P<0.01;6个月:WMD=11.01,95%CI:9.73-12.28,P<0.01;1年:WMD=10.78,95%CI:9.33-12.24,P<0.01];(2)与常规护理相比,加速康复外科护理能提高膝关节置换患者美国膝关节学会评分中膝评分(WMD=9.23,95%CI:0.86-17.6,P<0.05)。(3)与常规护理相比,加速康复外科护理降低术后深静脉血栓、便秘、肺部感染、泌尿系感染等并发症的发生。结论:与常规护理相比,加速康复外科护理能促进患者膝关节功能恢复、降低术后深静脉血栓、便秘、肺部感染、泌尿系感染的发生。但尚需进一步开展严谨的大样本、多中心的随机对照试验加以验证。

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.

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.

Safety and outcomes of hip and knee replacement surgery in liver transplant recipients

BACKGROUND Liver transplant(LT)is becoming increasingly common with improved life expectancy.Joint replacement is usually a safe procedure;however,its safety in LT recipients remains understudied.AIM To evaluate the mortality,outcome,and 90-d readmission rate in LT patients undergoing hip and knee replacement surgery.METHODS Patients with history of LT who underwent hip and knee replacement surgery between 2016 and 2019 were identified using the National Readmission Database.RESULTS A total of 5046119 hip and knee replacement surgeries were identified.3219 patients had prior LT.Mean age of patients with no history of LT was 67.51[95%confidence interval(CI):67.44-67.58],while it was 64.05(95%CI:63.55-64.54)in patients with LT.Patients with history of LT were more likely to have prolonged length of hospital stay(17.1%vs 8.4%,P<0.001).The mortality rate for patients with no history of LT was 0.22%,while it was 0.24%for patients with LT(P=0.792).Patients with history of LT were more likely to have re-admissions within 90 d of initial hospitalization:11.4%as compared to 6.2%in patients without history of LT(P<0.001).The mortality rate between both groups during readmission was not statistically different(1.9%vs 2%,P=0.871)respectively.CONCLUSION Hip and knee replacements in patients with history of LT are not associated with increased mortality;increased readmissions were more frequent in this cohort of patients.Chronic kidney disease and congestive heart failure appear to predict higher risk of readmission.

Shock-wave impact on the knee joint affected with osteoarthritis and after arthroplasty

Degenerative diseases significantly reduce the quality of human life.Non-invasive treatments are used in the initial stages of osteoarthritis(OA).Total knee arthroplasty is used in the late stages of osteoarthritis of the knee joint.Non-invasive methods based on mechanical action are also used for the rehabilitation of a patient after arthroplasty.This paper presents numerical models of the knee joint with degenerative OA changes and arthroplasty.Using these models,a computational study was made of the influence of the intensity of shock-wave exposure on the conditioning for the regeneration of bone and cartilage tissues.Based on the modeling results,it was found that in the knee joint with degenerative OA changes,conditions for the regeneration of cartilage and meniscus tissues were fulfilled under medium and highintensity loading.Under high-intensity loading(up to 0.9 m J/mm^(2)),the stress level was significantly below the ultimate value required for fracture.At knee arthroplasty,the conditions for bone tissue regeneration around the tibia component are fulfilled only under high-intensity loading.

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.

Formation process of extension knee joint contracture following external immobilization in rats

BACKGROUND Current research lacks a model of knee extension contracture in rats.AIM To elucidate the formation process of knee extension contracture.METHODS We developed a rat model using an aluminum external fixator.Sixty male Sprague-Dawley rats with mature bones were divided into the control group(n=6)and groups that had the left knee immobilized with an aluminum external fixator for 1,2,and 3 d,and 1,2,3,4,6,and 8 wk(n=6 in each group).The passive extension range of motion,histology,and expression of fibrosis-related proteins were compared between the control group and the immobilization groups.RESULTS Myogenic contracture progressed very quickly during the initial 2 wk of immobilization.After 2 wk,the contracture gradually changed from myogenic to arthrogenic.The arthrogenic contracture progressed slowly during the 1^(st) week,rapidly progressed until the 3^(rd) week,and then showed a steady progression until the 4^(rd) week.Histological analyses confirmed that the anterior joint capsule of the extended fixed knee became increasingly thicker over time.Correspondingly,the level of transforming growth factor beta 1(TGF-β1)and phosphorylated mothers against decapentaplegic homolog 2(p-Smad2)in the anterior joint capsule also increased with the immobilization time.Over time,the cross-sectional area of muscle fibers gradually decreased,while the amount of intermuscular collagen and TGF-β1,p-Smad2,and p-Smad3 was increased.Unexpectedly,the amount of intermuscular collagen and TGF-β1,p-Smad2,and p-Smad3 was decreased during the late stage of immobilization(6-8 wk).The myogenic contracture was stabilized after 2 wk of immobilization,whereas the arthrogenic contracture was stabilized after 3 wk of immobilization and completely stable in 4 wk.CONCLUSION This rat model may be a useful tool to study the etiology of joint contracture and establish therapeutic approaches.

Is the Prophylactic Administration of Povidone Iodine Intranasally Preoperatively in Elective Total Knee Replacement as Effective as MRSA Prophylactic Screening and Mupirocin Treatment?—A Retrospective Analysis

Surgical Site Infections (SSIs) remain a prevalent issue in healthcare. An average of 2% to 4% of all Total Knee Arthroplasties (TKA/TKR) result in a Prosthetic Joint Infection (PJI) (Ashraf et al. , 2018). These surgical site infections cause significant distress to the patient and require extended courses of antibiotic treatment and revision surgery of the infected joint. SSIs also reduce financial reimbursement to the surgery facility and affect the performing surgeon’s performance scores. To prevent surgical infection, healthcare facilities have implemented various screening or decolonization methods to prevent surgical infection to may cause infection. Various treatment methods exist for managing MRSA preoperatively which include Povidone Iodine (PI) application as a universal decolonization method and/or screening every patient pre-operatively for MRSA and treating MRSA-positive patients with Mupirocin ointment. Both interventions are well-established in the literature. At the author’s facility, the elective TKR populations were analyzed while each intervention was implemented. In 2019 TKR patients underwent MRSA swabbing and testing and in 2021 PI decolonization was the decolonization method of choice. The study revealed that MRSA testing and swabbing were better at reducing SSI related to MRSA than Povidone Iodine decolonization.

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.

Joint replacement and human immunodeficiency virus

The incidence of human immunodeficiency virus(HIV)-infected cases that need total joint replacement(TJR)is generally rising.On the other hand,modern management of HIV-infected cases has enabled them to achieve longevity while increasing the need for arthroplasty procedures due to the augmented degenerative joint disease and fragility fractures,and the risk of osteonecrosis.Although initial investigations on joint replacement in HIV-infected cases showed a high risk of complications,the recent ones reported acceptable outcomes.It is a matter of debate whether HIV-infected cases are at advanced risk for adverse TJR consequences;however,the weak immune profile has been associated with an increased probability of complications.Likewise,surgeons and physicians should be aware of the complication rate after TJR in HIV-infected cases and include an honest discussion of the probable unwelcoming complication with their patients contemplating TJR.Therefore,a fundamental review and understanding of the interaction of HIV and arthroplasty are critical.

Effect of flurbiprofen axetil analgesia after knee replacement on the cytokine contents in serum and joint fluid as well as HPA axis activity

Objective: To investigate the effect of flurbiprofen axetil analgesia after knee replacement on the cytokine contents in serum and joint fluid as well as HPA axis activity. Methods: Patients who underwent knee replacement in People's Hospital of Dongxihu District between April 2015 and January 2018 were selected as the research subjects and randomly divided into the experimental group who accepted flurbiprofen axetil combined with patient-controlled intravenous analgesia and the control group who accepted patient-controlled intravenous analgesia alone. The contents of cytokines and HPA axis-related hormones in serum were measured before surgery as well as 1 d and 3 d after surgery;the contents of cytokines in joint fluid were measured 1 d and 3 d after surgery. Results: Compared with those of same group before surgery, NGF, NPY, TNF-α, IL-2, IL-4, IL-10, ACTH, COR, INS, GH and PRL levels of both groups were increasing 1 d and 3 d after surgery, and NGF, NPY, TNF-α, IL-2, IL-4, IL-10, ACTH, COR, INS, GH and PRL levels in serum as well as PGE2, OPN, TGF-β1, FGF21, CXCL12 and YKL-40 in joint fluid of experimental group 1 d and 3 d after surgery were lower than those of control group. Conclusion: Flurbiprofen axetil analgesia after knee replacement can reduce the release of cytokines in serum and joint fluid, and inhibit the activity of HPA axis, and its analgesic effect is exact.

Two-stage revision in periprosthetic knee joint infections

Periprosthetic joint infection(PJI)following total knee arthroplasty is one of the most catastrophic and costly complications that carries significant patient wellness as well as economic burdens.The road to efficiently diagnosing and treating PJI is challenging,as there is still no gold standard method to reach the diagnosis as early as desired.There are also international controversies with respect to the best approach to manage PJI cases.In this review,we highlight recent advances in managing PJI following knee arthroplasty surgery and discuss in depth the two-stage revision method.

“Meniscal” scar as a landmark for the joint line in revision total knee replacement

AIM To determine whether tissue identified at the joint line was actually remnant "meniscal" scar tissue or not. METHODS Nine patients undergoing revision knee surgery following informed consent had meniscal scar tissue sent to the histology department for analyses. All revisions were performed where joint line had been raised or lowered at earlier surgery. Although preoperative radiographic evaluations suggested that the joint line had been altered, intraoperatively there was scar tissue at the level of the recreated joint line. This scar tissue has traditionally been described as meniscal scar, and to identify the origins of this tissue, samples were sent for histological analyses. The tissue samples were stored in formalin, and embedded and sectioned before undergoing histochemical staining. All samples underwent macroscopic and microscopic examination by a histopathologist who was blind to the study aims. The specific features that were examined included tissue organisation, surface and central composition, cellular distribution including histiocytes, nuclear ratio and vasculature. Atypical and malignant features, inflammation and degeneration were specifically looked for. A statistical review of the study was performed by a biomedical statistician.RESULTS The histological findings for the nine patients showingthe macroscopic and microscopic findings, and the conclusion are outlined in a Table. The histological analyses were reviewed to determine whether the tissue samples were likely to be meniscal scar tissue. The response was yes(2, 22%), no(6, 67%) and maybe(1,11%) based on the conclusions. The results were "yes"when on macroscopy, firm cream tissue was identified.In these two "yes" samples, microscopic analyses showed organised fibrous tissue with focal degenerative areas with laminated pattern associated with histiocytes peripherally but no inflammation. The "no" samples were assessed macroscopically and microscopically and were deemed to have appearances representing fibrous synovial tissue and features in keeping with degenerate scar tissue or connective tissue. One sample was indeterminate and microscopically contained fibrocollagenous tissue with synovial hyperplasia. It also contained some degenerate hyalinised tissue that may represent cartilage, but the appearances were not specific. CONCLUSION Based on our pilot study, we recommend reliance on a number of markers to identify the joint line as outlined above, and to exercise caution in using the "meniscal"scar.

Perioperative blood management strategies for patients undergoing total knee replacement:Where do we stand now?

Total knee replacement(TKR) is one of the most common surgeries over the last decade. Patients undergoing TKR are at high risk for postoperative anemia and furthermore for allogeneic blood transfusions(ABT). Complications associated with ABT including chills, rigor, fever, dyspnea, light-headedness should be early recognized in order to lead to a better prognosis. Therefore, perioperative blood management program should be adopted with main aim to reduce the risk of blood transfusion while maximizing hemoglobin simultaneously. Many blood conservation strategies have been attempted including preoperative autologous blood donation, acute normovolemic haemodilution, autologous blood transfusion, intraoperative cell saver, drain clamping, pneumatic tourniquet application, and the use of tranexamic acid. For practical and clinical reasons we will try to classify these strategies in three main stages/pillars: Pre-operative optimization, intra-operative and post-operative protocols. The aim of this work is review the strategies currently in use and reports our experience regarding the perioperative blood management strategies in TKR.

Common controversies in total knee replacement surgery: Current evidence

Total knee replacement(TKR) is a widely used operation that has radically improved the quality of life of millions of people during the last few decades. However, some technical details, concerning the surgical procedure and the rehabilitation following total knee arthroplasty, are still a matter of a strong debate. In this review of the literature, we have included the best evidence available of the last decade, in an effort to shed light on some of the most controversial subjects related to TKR surgery. Posterior-stabilized or cruciate-retaining prosthesis? To use a tourniquet during operation or not? Do patients need continuous passive motion for their post-surgery rehabilitation? To resurface patella or not? These are some of the most controversial topics that until now have been persistent dilemmas for the orthopedic surgeon. Results of this systematic review of the literature are highly controversial. These conflicting results are an indication that larger and more well conducted high quality trials are needed in order to gain more secure answers. At the same time, it is becoming apparent that a meticulous operative technique, respecting the soft tissue envelope and knowing the principles of alignment and soft tissue balancing, aresome of the parameters that might contribute more to achieving the optimal results for the patients.

The Knee Joint Design and Control of Above-knee Intelligent Bionic Leg Based on Magneto-rheological Damper

The above-knee intelligent bionic leg is very helpful to amputees in the area of rehabilitation medicine. This paper first introduces the functional demand of the above-knee prosthesis design. Then, the advantages of the four-bar link mechanism and the magneto-rheological （MR） damper are analyzed in detail. The fixed position of the MR damper is optimized and a virtual prototype of knee joint is given. In the end, the system model of kinematics, dynamics, and controller are given and a control experiment is performed. The control experiment indicates that the intelligent bionic leg with multi-axis knee is able to realize gait tracking of the amputee＇s healthy leg based on semi-active control of the MR damper.

Persistent post-surgical pain and neuropathic pain after total knee replacement

AIM: To study the prevalence of persistent post-surgical pain(PPSP) and neuropathic pain(NP) after total knee replacement(TKR).METHODS: MEDLINE and Embase databases were searched for articles published until December 2014 in English language. Published articles were included if they referred to pain that lasts at least 3 mo after primary TKR for knee osteoarthritis, and measured pain with pain specific instruments. Studies that referred to pain caused by septic reasons and implant malalignment were excluded. Both prospective and retrospective studies were included and only 14 studies that match the inclusion criteria were selected for this review.RESULTS: The included studies were characterized by the heterogeneity on the scales used to measure pain and pre-operative factors related to PPSP and NP. The reported prevalence of PPSP and NP seems to be relatively high, but it varies among different studies. There is also evidence that the prevalence of post-surgical pain is related to the scale used for pain measurement. The prevalence of PPSP is ranging at 6 mo from 16% to 39% and at 12 mo from 13.1% to 23% and even 38% of the patients. The prevalence of NP at 6 mo post-operatively is ranging from 5.2% to13%. Pre-operative factors related to the development of PPSP also differ, including emotional functioning, such as depression and pain catastrophizing, number of comorbidities, pain problems elsewhere and operations in knees with early grade of osteoarthritis.CONCLUSION: No firm conclusions can be reached regarding the prevalence of PPSP and NP and the related factors due to the heterogeneity of the studies.

A Biomimetic Hip Joint Simulator and its Application in in vitro Study of the Integrity of Replacement Cemented Hip

A biomimetic hip joint simulator that can be used to evaluate the outcome of the cemented total hip replacement has been designed, manufactured and evaluated. The simulator produces motion in the extension/flexion plane, with a socket to rotate internal/externally. At the same time a dynamic loading cycle is applied. A validation test was performed on a cemented femoral stem within a novel composite femur. The hone quality has a strong effect on the stem migration and on the integrity of the interfaces. The migration of the stem is a combination of 3-D translation and rotation of the stem. Under the same loading conditions, weak bone allows more stem migration than strong bone. There is a great decrease in the strength of the stem-cement interface after the dynamic test, and the weak bone composite exhibited a greater reduction in interfacial strength than the strong bone composite. The decrease of the interfacial strength indicates that the primary bonding between the stem and the cement mantle had deteriorated and the integrity of stem-cement interface was damaged. The study demonstrates the value of using a hip joint simulator to investigate stem migration and interface integrity within the cemented hip replacement, suggesting that method can be used for in vitro evaluation of the biomaterials used in the cemented hip replacements.

THREE-DIMENSIONAL FINITE ELEMENT SIMULATION OF TOTAL KNEE JOINT IN GAIT CYCLE

Based on CT scanning pictures from a volunteer＇s knee joint, a three-dimensional finite element model of the healthy human knee joint is constructed including complete femur, tibia, fibular, patellar and the main cartilage and ligaments. This model was validated using experimental and numerical results obtained from other authors. The pressure distribution of contact surfaces of knee joint are calculated and analyzed under the load action of ‘heel strike＇, ‘single limb stance＇ and ‘toe-off＇. The results of the gait cycle are that the contact areas of medial cartilage are larger than that of lateral cartilage; the contact force and contact areas would grow larger with the load increasing; the pressure of lateral meniscus is steady, relative to the significant variation of peak pressure in medial meniscus; and the peak value of contact pressure on all components are usually found at about 4570 of the gait cycle.