Focusing on the ball double-screw hydraulic knee joint as the research object,this paper analyzes the load driving performance of the hydraulic knee joint.Taking the posture data of the human body such as walking,squa...Focusing on the ball double-screw hydraulic knee joint as the research object,this paper analyzes the load driving performance of the hydraulic knee joint.Taking the posture data of the human body such as walking,squatting and landing buffer as initial learning objects,motion features are extracted.By simplifying the trajectories of different motion actions into key feature control points and flexible trajectory fitting,the trajectory of joint actions is optimized.This method can realize the adaptability of the hydraulic robot knee joint in different movements,and take the flexible action as the optimization goal under the condition of ensuring the movement performance,so as to reduce the damage to the knee joint caused by the foot impact in motion.The simulation model was built by Adams and Matlab to complete the performance analysis and motion optimization experiment of the knee joint.The simulation results show that the foot impact force of the experimental model decreases gradually through optimization.Finally,the method is applied to the hydraulic joint experimental prototype to prove its load capacity and flexible motion control performance.展开更多
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...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.展开更多
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....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.展开更多
Purpose: The purpose is to study whether pain and inflammation in knee joint osteoarthritis (OA) are associated with local synovial neuronal changes. Methods: Synovial biopsies were harvested from the medial and later...Purpose: The purpose is to study whether pain and inflammation in knee joint osteoarthritis (OA) are associated with local synovial neuronal changes. Methods: Synovial biopsies were harvested from the medial and lateral knee compartments from OA patients undergoing total joint replacement surgery. All patients had predominant pain at the medial joint compartment. Pain and knee joint function were evaluated by knee society score (KSS). Synovial inflammation was analyzed by histopathological analysis and expression of growth associated protein-43 (GAP-43), sensory (SP, CGRP) and autonomic (NPY, VIP, TH) neuropeptides was studied by single and double immunohistochemistry techniques. Results: We observed reduced KSS and increased inflammatory score in synovial membrane of medial knee compartment. A significant increase in GAP-43 [P = 0.001], SP [P = 0.05], CGRP [P = 0.05] and TH [P = 0.05] expression was observed and SP, CGRP and NPY were found to be co-existed predominantly with GAP-43 in synovial membrane collected from medial compared to the lateral knee compartment. Conclusions: Regenerating nerve fibers containing sensory and autonomic neuropeptides are associated with pain and inflammation in knee joint OA.展开更多
Despite remarkable improvements in clinical outcomes after anterior cruciate ligament reconstruction,the residual rotational instability of knee joints remains a major concern.The anterolateral ligament(ALL)has recent...Despite remarkable improvements in clinical outcomes after anterior cruciate ligament reconstruction,the residual rotational instability of knee joints remains a major concern.The anterolateral ligament(ALL)has recently gained attention as a distinct ligamentous structure on the anterolateral aspect of the knee joint.Numerous studies investigated the anatomy,function,and biomechanics of ALL to establish its potential role as a stabilizer for anterolateral rotational instability.However,controversies regarding its existence,prevalence,and femoral and tibial insertions need to be addressed.According to a recent consensus,ALL exists as a distinct ligamentous structure on the anterolateral aspect of the knee joint,with some anatomic variations.The aim of this article was to review the updated anatomy of ALL and present the most accepted findings among the existing controversies.Generally,ALL originates slightly proximal and posterior to the lateral epicondyle of the distal femur and has an anteroinferior course toward the tibial insertion between the tip of the fibular head and Gerdy’s tubercle below the lateral tibial plateau.展开更多
Synovial osteochondromatosis is a rare, benign condition of unknown etiology in which the synovium undergoes metaplasia, leading to cartilaginous nodules that ultimately break free, mineralize, and even ossify. The mo...Synovial osteochondromatosis is a rare, benign condition of unknown etiology in which the synovium undergoes metaplasia, leading to cartilaginous nodules that ultimately break free, mineralize, and even ossify. The most commonly involved joint is the knee. Typically, radiographs can be diagnostic and mineralized nodules are pathognomonic. In as many as one-third of cases, however, no calcification or ossification of the cartilage occurs in the early stage of the disease because mineralization is time-dependent. In such cases, gadolinium-enhanced MRI can be useful. Unmineralized nodules are typically peripherally enhanced because they are attached to and derive a vascular supply from the synovium. We experienced an unmineralized case of synovial osteochondromatosis of the right knee joint, in which imaging diagnosis was difficult. Neither calcification nor ossification was observed, but all nodules were released from the synovium as loose bodies and there was no vascular supply. Therefore, MRI did not show a typical appearance. These findings suggest that synovial osteochondromatosis should be considered as a differential diagnosis in a case in which unmineralized loose bodies without a synovial lesion are found in an imaging examination.展开更多
Objective:To investigate the expression changes and clinical significance of Toll-like receptor-4(TLR-4)and interleukin-1β(IL-1β)in the serum and knee joint fluid in patients with knee osteoarthritis(KOA).Methods:Fr...Objective:To investigate the expression changes and clinical significance of Toll-like receptor-4(TLR-4)and interleukin-1β(IL-1β)in the serum and knee joint fluid in patients with knee osteoarthritis(KOA).Methods:From June 2017 to December 2018,220 cases of patients with KOA who were admitted in Department of Orthopedics of the Third Affiliated Hospital of Inner Mongolia Medical University(“our hospital”for short)were selected as the observation group.According to the severity of KOA,they were divided into the mild subgroup(n=98),the moderate subgroup(n=80)and the severe subgroup(n=42).In addition,60 cases of volunteers who received the physical examination in Health Medical Center of our hospital were selected as the control group.The levels of TLR-4 and IL-1βin the serum and knee joint fluid were detected by enzyme-linked immunosorbent assay,in order to analyze the correlation of TLR-4 and IL-1βlevels with the severity of KOA.Results:The levels of TLR-4 and IL-1βin the serum and knee joint fluid of the observation group were significantly higher than those of the control group,and the differences were statistically significant(all p<.05).The levels of TLR-4 and IL-1βin the serum and knee joint fluid of the severe subgroup were significantly higher than those of the mild subgroup and the moderate subgroup,and the levels of TLR-4 and IL-1βin the serum and knee joint fluid of the moderate subgroup were higher than those of the mild group.The differences were statistically significant(all p<.05).The levels of TLR-4 and IL-1βin the serum and knee joint fluid were positively correlated to the severity of KOA(r=.706,.729,.741,.715,all p<.05);in the serum,the level of TLR-4 was positively correlated to the level of IL-1β(r=.720,p<.05);in the joint fluid,the level of TLR-4 was positively correlated to the level of IL-1β(r=.736,p<.05).Conclusions:The levels of TLR-4 and IL-1βin the serum and knee joint fluid of KOA patients are abnormally increased,which is closely related with the severity of KOA.It can be used for clinical prediction,diagnosis and treatment of KOA.展开更多
Prosthetic joint infection is a rare manifestation of Yersinia enterocolitica. We report a case of a patient presenting with fever and a purulent infection in his prosthetic knee joint caused by Y. enterocolitica. He ...Prosthetic joint infection is a rare manifestation of Yersinia enterocolitica. We report a case of a patient presenting with fever and a purulent infection in his prosthetic knee joint caused by Y. enterocolitica. He had been operated in 1990 for arthrosis of the right knee. Re-operation was performed in 2007 for loosening of the prosthesis. Seven months later, following progressively increasing knee pain, he became acutely febrile and a purulent knee joint infection was diagnosed. Y. enterocolitica was isolated from the joint fluid. Serum antibodies against Y. enterocolitica were also positive. He was treated with debridement, replacement of the liner component of the prosthesis and a long course of intravenous antimicrobial therapy. The infection was thought to be in a chronic suppressive state. The final outcome after all therapy was good.展开更多
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 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.展开更多
Knee osteoarthritis is a chronic, indolent disease that will affect an ever increasing number of patients, especially the elderly and the obese. It is characterized by degeneration of the cartilage substance inside th...Knee osteoarthritis is a chronic, indolent disease that will affect an ever increasing number of patients, especially the elderly and the obese. It is characterized by degeneration of the cartilage substance inside the knee which leads to pain, stiffness and tenderness. By some estimations in 2030, only in the United States, this medical condition will burden 67 million people. While conventional treatments like physiotherapy or drugs offer temporary relief of clinical symptoms, restoration of normal cartilage function has been difficult to achieve. Moreover, in severe cases of knee osteoarthritis total knee replacement may be required. Total knee replacements come together with high effort and costs and are not always successful. The aim of this review is to outline the latest advances in stem cell therapy for knee osteoarthritis as well as highlight some of the advantages of stem cell therapy over traditional approaches aimed at restoration of cartilage function in the knee. In addition to the latest advances in the field, challenges associated with stem cell therapy regarding knee cartilage regeneration and chondrogenesis in vitro and in vivo are also outlined and analyzed. Furthermore, based on their critical assessment of the present academic literature the authors of this review share their vision about the future of stem cell applications in the treatment of knee osteoarthritis.展开更多
Objective: To examine the changes of mu-opioid receptors (MORs) expression in human chronic inflamed knee joint synovium tissue. Methods:Knee joint synovium tissues were taken from 21 patients with chronic arthritis (...Objective: To examine the changes of mu-opioid receptors (MORs) expression in human chronic inflamed knee joint synovium tissue. Methods:Knee joint synovium tissues were taken from 21 patients with chronic arthritis (inflamed group) and 6 fresh bodies with normal knee joints (control group). And the expression of MORs was detected by using immunohistochemistry. flow cytometry(FCM) and reverse-transcription polymerase chain reaction (RT-PCR). Results: The expression of MORs in the inflamed group was significantly higher than that in the normal group by using the 3 techniques(P<0. 05). Conclusion: Chronic inflammation enhances the up-regulation of MORs in human knee joint synovium tissue.展开更多
This study aimed at examining the differences in leg strength and activities of daily living (ADL) ability among groups with various knee problems. The subjects consisted of 328 elderly females who were classified int...This study aimed at examining the differences in leg strength and activities of daily living (ADL) ability among groups with various knee problems. The subjects consisted of 328 elderly females who were classified into three groups: those without knee pain or a knee disorder, those with knee pain, and those with a knee disorder. The subjects took a knee extension strength test and an ADL survey. Knee extension strength and ADL scores (total score and each domain score of the motions of locomotion, posture change, stability, and manipulation) were selected as the evaluation parameters. The knee extension strength, total ADL score and each domain score of the motions of locomotion, posture change, and stability ranged from low to high in the following order: the group with a knee disorder, the group with knee pain, and the group without pain or a knee disorder. Moreover, manipulation scores were significantly inferior in the group with a knee disorder compared with the other two groups. In conclusion, the female elderly with knee pain or a knee disorder have inferior knee extension strength and ADL with respect to the motions of locomotion, posture change and stability. In addition, with regard toknee extension strength with respect to theabove three motions, the elderly with a knee disorder have inferior scores when compared with the elderly who have only knee pain;thus, they find it difficult to perform activities involving the knee joints.展开更多
Objective To explore the relative factors affecting the functional restoration of knee joint after the fracture of patella, and to anticipate the effect of middle-term and short-time rehabilitation therapy. Method 23 ...Objective To explore the relative factors affecting the functional restoration of knee joint after the fracture of patella, and to anticipate the effect of middle-term and short-time rehabilitation therapy. Method 23 patients with limited flexion function of knee joint after the fracture of patella, accepted the routine rehabilitation treatment in out -patient service, and some of the patients adopted local heat therapy at the same time. The 13 factors have been selected for regression analysis step by step under the help of SPSS statistical software. Result The flexible degree of the knee joint before rehabilitation (X1), the non-smooth posterior edge of patella (X2), and the immobilization time of the joint (X3) are relative factors for the flexible degree of knee joint 1 month after rehabilitation (Y1) and the flexible degree of knee joint 3 months after rehabilitation (Y2), and Y1 can also be affected by whether surgery therapy or not (X4), (partial regression coefficient P< 0.05). The differences between theoretical mean and practical mean of Y1 and Y2 are 5.6% and 4.2% respectively in the 23 cases. Conclusion The flexible degree of the knee joint before rehabilitation, whether the posterior edge of patella is smooth or not, and the immobilization time of the joint are relative factors affecting the middle-term and short-term flexible function of knee joint after the fracture of patella, and short-term restoration can also be affected by whether surgery therapy or not. The effects of middle-term and short-term rehabilitation can be predicted by regression equation primarily.展开更多
Two cases are presented of patients with a history of metastatic rectal adenocarcinoma presenting with a painful joint effusion. Both cases are potential examples of metastasis to periarticular bone with local infiltr...Two cases are presented of patients with a history of metastatic rectal adenocarcinoma presenting with a painful joint effusion. Both cases are potential examples of metastasis to periarticular bone with local infiltration to the synovium, which is one proposed mechanism of intrasynovial metastasis. While skeletal metastases are a relatively common occurrence in metastatic adenocarcinoma, intraarticular metastasis is extremely rare. These cases highlight the need to consider metastasis in the differential of joint swelling in the setting of a history of adenocarcinoma.展开更多
Objective: To discuss a method to establish a three-dimensional model of healthy human knee joint, which can be used for further knee joint biomechanics analysis and simulation. Methods: CT scan and medical image thre...Objective: To discuss a method to establish a three-dimensional model of healthy human knee joint, which can be used for further knee joint biomechanics analysis and simulation. Methods: CT scan and medical image three-dimensional reconstruction software (Mimics) were used to obtain the knee joint three-dimensional finite element model (FEM) according to reverse engineering theory. Results: FEM of knee joint with complete bone structure was established by Mimics. Conclusion: Three-dimensional FEM was established according to CT images exports as IGES file. The model can be used for knee joint biomechanics finite element analysis to provide references and proposals for the clinical diagnoses of knee joint illness, and the design of artificial knee joint prosthesis.展开更多
Background Diffusion-weighted imaging(DWI)of synovitis has been suggested as a possible non-invasive alternative to contrast-enhanced T1w imaging(ce-T1w).We aimed to study DWI for diagnosing synovitis in the knee join...Background Diffusion-weighted imaging(DWI)of synovitis has been suggested as a possible non-invasive alternative to contrast-enhanced T1w imaging(ce-T1w).We aimed to study DWI for diagnosing synovitis in the knee joint of pediatric patients,to quantify inter-observer agreement on DWI and ce-T1w and to calculate quantitative measures of synovial diffusivity and conspicuity.Methods Forty consecutive patients with known or suspected arthritis of the knee(25 girls,median age 12 years)underwent routine 1.5T MRI with ce-T1w and transverse DWI with b values 50 and 800 s/mm2.Mean apparent diffusion coefficient(ADC)values and signal intensity of inflamed synovium,joint effusion and muscle were measured with regions of interest retrospectively.Post-contrast T1 w images(diagnostic standard)and diffusion-weighted images at b=800 s/mm2 with ADC map were separately rated by three independent and blinded readers with different levels of expertise for the presence and degree of synovitis along with the level of diagnostic confidence.Results Thirty-one(78%)patients showed at least some synovial contrast enhancement,17(43%)children were diagnosed with synovitis on ce-T1w.Ratings by the 1st reader on ce-T1w and on DWI for synovitis showed very good agreement(kappa=0.90).Inter-observer agreement on DWI ranged from moderate to substantial with kappa values between 0.68 and 0.79(all P<0.001).Agreement and diagnostic confidence were generally lower in patients with mild and without synovial enhancement,compared to patients with synovitis.DWI yielded higher signal of inflamed synovium vs.muscle tissue,but lower signal vs.joint effusion,compared to ce-T1 w(all P<0.001).Conclusions Diffusion-weighted imaging is a promising,though reader-dependent alternative to contrast-enhanced imaging in patients with arthritis of the knee,based on our preliminary findings.It holds potential for increasing patient safety and comfort.展开更多
In order to study the three jump training and competition on knee joint impact damage degree,left knee joint of one healthy male athletes is used as the research object,a complete knee three-dimensional model was esta...In order to study the three jump training and competition on knee joint impact damage degree,left knee joint of one healthy male athletes is used as the research object,a complete knee three-dimensional model was established based on the jumper’s knee CT scan and magnetic resonance imaging(MRI),including the femur,tibia,fibula,patella and knee major cartilage,ligaments.The multi-body dynamics analysis(MDA)and finite element analysis(FEA)method are used to calculate the three jump,jump starting,landing process of athletes knee joint impact,the state should change the status of stress,strain and displacement.The results show that in the three jump process,the load on the lateral contact area of the knee joint is the largest,the displacement is the largest,and it increases with the impact of jump and landing.This exacerbated the degree of wear and tear of the tibia,it tends to induce knee injury in athletes.The results show that the combination of finite element and MDA can better study the knee joint’s shock and vibration during the three-level jump training and competition,and these open up a new research method for the knee joint injury.It also provides a certain reference for the prevention and treatment of knee joint injury.展开更多
基金supported by the Top Discipline Plan of Shanghai Universities-Class I,the National Natural Science Foundation of China(52205279)the China National Postdoctoral Program for Innovative Talents(BX20190242)+1 种基金the Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems(GZKF-202017)the Open Foundation of the National Engineering Technology Research Center for Prefabrication Construction in Civil Engineering(2021CPCCE-K02).
文摘Focusing on the ball double-screw hydraulic knee joint as the research object,this paper analyzes the load driving performance of the hydraulic knee joint.Taking the posture data of the human body such as walking,squatting and landing buffer as initial learning objects,motion features are extracted.By simplifying the trajectories of different motion actions into key feature control points and flexible trajectory fitting,the trajectory of joint actions is optimized.This method can realize the adaptability of the hydraulic robot knee joint in different movements,and take the flexible action as the optimization goal under the condition of ensuring the movement performance,so as to reduce the damage to the knee joint caused by the foot impact in motion.The simulation model was built by Adams and Matlab to complete the performance analysis and motion optimization experiment of the knee joint.The simulation results show that the foot impact force of the experimental model decreases gradually through optimization.Finally,the method is applied to the hydraulic joint experimental prototype to prove its load capacity and flexible motion control performance.
基金financial support of the Russian Foundation for Basic Research,grant No.20-08-00818(simulation results)the Government research assignment for ISPMS SB RAS,project FWRW-2021-009(in-house software development)。
文摘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.
基金Supported by Anhui Key Research and Development Program-Population Health,No.201904a07020067Anhui Provincial Health Research Project,No.AHWJ2022b063+2 种基金Clinical Medicine Discipline Construction Project of Anhui Medical University in 2022(Clinic and Preliminary Co-Construction Discipline Project),No.2022 lcxkEFY0102022 National Natural Science Foundation Incubation Plan,No.2022GMFY05Clinical Medicine Discipline Construction Project of Anhui Medical University in 2022(High-Level Personnel Training Program),No.2022 lcxkEFY04,No.2022 lcxkEFY05.
文摘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.
文摘Purpose: The purpose is to study whether pain and inflammation in knee joint osteoarthritis (OA) are associated with local synovial neuronal changes. Methods: Synovial biopsies were harvested from the medial and lateral knee compartments from OA patients undergoing total joint replacement surgery. All patients had predominant pain at the medial joint compartment. Pain and knee joint function were evaluated by knee society score (KSS). Synovial inflammation was analyzed by histopathological analysis and expression of growth associated protein-43 (GAP-43), sensory (SP, CGRP) and autonomic (NPY, VIP, TH) neuropeptides was studied by single and double immunohistochemistry techniques. Results: We observed reduced KSS and increased inflammatory score in synovial membrane of medial knee compartment. A significant increase in GAP-43 [P = 0.001], SP [P = 0.05], CGRP [P = 0.05] and TH [P = 0.05] expression was observed and SP, CGRP and NPY were found to be co-existed predominantly with GAP-43 in synovial membrane collected from medial compared to the lateral knee compartment. Conclusions: Regenerating nerve fibers containing sensory and autonomic neuropeptides are associated with pain and inflammation in knee joint OA.
基金Supported by a grant of Korea University Anam Hospital,Seoul,Republic of Korea,No.K2209741.
文摘Despite remarkable improvements in clinical outcomes after anterior cruciate ligament reconstruction,the residual rotational instability of knee joints remains a major concern.The anterolateral ligament(ALL)has recently gained attention as a distinct ligamentous structure on the anterolateral aspect of the knee joint.Numerous studies investigated the anatomy,function,and biomechanics of ALL to establish its potential role as a stabilizer for anterolateral rotational instability.However,controversies regarding its existence,prevalence,and femoral and tibial insertions need to be addressed.According to a recent consensus,ALL exists as a distinct ligamentous structure on the anterolateral aspect of the knee joint,with some anatomic variations.The aim of this article was to review the updated anatomy of ALL and present the most accepted findings among the existing controversies.Generally,ALL originates slightly proximal and posterior to the lateral epicondyle of the distal femur and has an anteroinferior course toward the tibial insertion between the tip of the fibular head and Gerdy’s tubercle below the lateral tibial plateau.
文摘Synovial osteochondromatosis is a rare, benign condition of unknown etiology in which the synovium undergoes metaplasia, leading to cartilaginous nodules that ultimately break free, mineralize, and even ossify. The most commonly involved joint is the knee. Typically, radiographs can be diagnostic and mineralized nodules are pathognomonic. In as many as one-third of cases, however, no calcification or ossification of the cartilage occurs in the early stage of the disease because mineralization is time-dependent. In such cases, gadolinium-enhanced MRI can be useful. Unmineralized nodules are typically peripherally enhanced because they are attached to and derive a vascular supply from the synovium. We experienced an unmineralized case of synovial osteochondromatosis of the right knee joint, in which imaging diagnosis was difficult. Neither calcification nor ossification was observed, but all nodules were released from the synovium as loose bodies and there was no vascular supply. Therefore, MRI did not show a typical appearance. These findings suggest that synovial osteochondromatosis should be considered as a differential diagnosis in a case in which unmineralized loose bodies without a synovial lesion are found in an imaging examination.
文摘Objective:To investigate the expression changes and clinical significance of Toll-like receptor-4(TLR-4)and interleukin-1β(IL-1β)in the serum and knee joint fluid in patients with knee osteoarthritis(KOA).Methods:From June 2017 to December 2018,220 cases of patients with KOA who were admitted in Department of Orthopedics of the Third Affiliated Hospital of Inner Mongolia Medical University(“our hospital”for short)were selected as the observation group.According to the severity of KOA,they were divided into the mild subgroup(n=98),the moderate subgroup(n=80)and the severe subgroup(n=42).In addition,60 cases of volunteers who received the physical examination in Health Medical Center of our hospital were selected as the control group.The levels of TLR-4 and IL-1βin the serum and knee joint fluid were detected by enzyme-linked immunosorbent assay,in order to analyze the correlation of TLR-4 and IL-1βlevels with the severity of KOA.Results:The levels of TLR-4 and IL-1βin the serum and knee joint fluid of the observation group were significantly higher than those of the control group,and the differences were statistically significant(all p<.05).The levels of TLR-4 and IL-1βin the serum and knee joint fluid of the severe subgroup were significantly higher than those of the mild subgroup and the moderate subgroup,and the levels of TLR-4 and IL-1βin the serum and knee joint fluid of the moderate subgroup were higher than those of the mild group.The differences were statistically significant(all p<.05).The levels of TLR-4 and IL-1βin the serum and knee joint fluid were positively correlated to the severity of KOA(r=.706,.729,.741,.715,all p<.05);in the serum,the level of TLR-4 was positively correlated to the level of IL-1β(r=.720,p<.05);in the joint fluid,the level of TLR-4 was positively correlated to the level of IL-1β(r=.736,p<.05).Conclusions:The levels of TLR-4 and IL-1βin the serum and knee joint fluid of KOA patients are abnormally increased,which is closely related with the severity of KOA.It can be used for clinical prediction,diagnosis and treatment of KOA.
基金supported by the Turku University Hospital and the Anne and Rauno Puolimatka Foundation.
文摘Prosthetic joint infection is a rare manifestation of Yersinia enterocolitica. We report a case of a patient presenting with fever and a purulent infection in his prosthetic knee joint caused by Y. enterocolitica. He had been operated in 1990 for arthrosis of the right knee. Re-operation was performed in 2007 for loosening of the prosthesis. Seven months later, following progressively increasing knee pain, he became acutely febrile and a purulent knee joint infection was diagnosed. Y. enterocolitica was isolated from the joint fluid. Serum antibodies against Y. enterocolitica were also positive. He was treated with debridement, replacement of the liner component of the prosthesis and a long course of intravenous antimicrobial therapy. The infection was thought to be in a chronic suppressive state. The final outcome after all therapy was good.
基金supported by China Postdoctoral Science Foundation(No. 20080441093)Key Laboratory Foundation of Liaoning Province(No. 2008S088)Postdoctoral Science Foundation of Northeastern University (No. 20080411)
文摘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.
文摘Knee osteoarthritis is a chronic, indolent disease that will affect an ever increasing number of patients, especially the elderly and the obese. It is characterized by degeneration of the cartilage substance inside the knee which leads to pain, stiffness and tenderness. By some estimations in 2030, only in the United States, this medical condition will burden 67 million people. While conventional treatments like physiotherapy or drugs offer temporary relief of clinical symptoms, restoration of normal cartilage function has been difficult to achieve. Moreover, in severe cases of knee osteoarthritis total knee replacement may be required. Total knee replacements come together with high effort and costs and are not always successful. The aim of this review is to outline the latest advances in stem cell therapy for knee osteoarthritis as well as highlight some of the advantages of stem cell therapy over traditional approaches aimed at restoration of cartilage function in the knee. In addition to the latest advances in the field, challenges associated with stem cell therapy regarding knee cartilage regeneration and chondrogenesis in vitro and in vivo are also outlined and analyzed. Furthermore, based on their critical assessment of the present academic literature the authors of this review share their vision about the future of stem cell applications in the treatment of knee osteoarthritis.
基金supported by the National Natural Science Foundation of China(No.10702048).
文摘基于从一个志愿者的膝关节扫描图画的 CT，健康的人的膝关节的一个三维的有限元素模型包括完全的腿节被构造，胫骨，腓骨，膝盖骨并且主要软骨和系带。这个模型用从另外的作者获得的试验性、数字的结果被验证。膝关节的接触表面的压力分发在‘ h 鳗 strike' ，‘ s 壁炉手足 stance' 和‘ t oe-off' 的负担行动下面计算、分析。步法周期的结果是中间的软骨的接触区域比侧面的软骨的大；接触力量和接触区域将变得更大，负担增加；侧面的新月的压力是稳定的，相对在中间的新月的山峰压力的重要变化；并且所有部件上的接触压力的山峰价值通常在大约 45% 步法周期点被发现。
基金Supported by Science and Research Foundation of Shanghai Municipal Health Bureau (200537103)
文摘Objective: To examine the changes of mu-opioid receptors (MORs) expression in human chronic inflamed knee joint synovium tissue. Methods:Knee joint synovium tissues were taken from 21 patients with chronic arthritis (inflamed group) and 6 fresh bodies with normal knee joints (control group). And the expression of MORs was detected by using immunohistochemistry. flow cytometry(FCM) and reverse-transcription polymerase chain reaction (RT-PCR). Results: The expression of MORs in the inflamed group was significantly higher than that in the normal group by using the 3 techniques(P<0. 05). Conclusion: Chronic inflammation enhances the up-regulation of MORs in human knee joint synovium tissue.
文摘This study aimed at examining the differences in leg strength and activities of daily living (ADL) ability among groups with various knee problems. The subjects consisted of 328 elderly females who were classified into three groups: those without knee pain or a knee disorder, those with knee pain, and those with a knee disorder. The subjects took a knee extension strength test and an ADL survey. Knee extension strength and ADL scores (total score and each domain score of the motions of locomotion, posture change, stability, and manipulation) were selected as the evaluation parameters. The knee extension strength, total ADL score and each domain score of the motions of locomotion, posture change, and stability ranged from low to high in the following order: the group with a knee disorder, the group with knee pain, and the group without pain or a knee disorder. Moreover, manipulation scores were significantly inferior in the group with a knee disorder compared with the other two groups. In conclusion, the female elderly with knee pain or a knee disorder have inferior knee extension strength and ADL with respect to the motions of locomotion, posture change and stability. In addition, with regard toknee extension strength with respect to theabove three motions, the elderly with a knee disorder have inferior scores when compared with the elderly who have only knee pain;thus, they find it difficult to perform activities involving the knee joints.
文摘Objective To explore the relative factors affecting the functional restoration of knee joint after the fracture of patella, and to anticipate the effect of middle-term and short-time rehabilitation therapy. Method 23 patients with limited flexion function of knee joint after the fracture of patella, accepted the routine rehabilitation treatment in out -patient service, and some of the patients adopted local heat therapy at the same time. The 13 factors have been selected for regression analysis step by step under the help of SPSS statistical software. Result The flexible degree of the knee joint before rehabilitation (X1), the non-smooth posterior edge of patella (X2), and the immobilization time of the joint (X3) are relative factors for the flexible degree of knee joint 1 month after rehabilitation (Y1) and the flexible degree of knee joint 3 months after rehabilitation (Y2), and Y1 can also be affected by whether surgery therapy or not (X4), (partial regression coefficient P< 0.05). The differences between theoretical mean and practical mean of Y1 and Y2 are 5.6% and 4.2% respectively in the 23 cases. Conclusion The flexible degree of the knee joint before rehabilitation, whether the posterior edge of patella is smooth or not, and the immobilization time of the joint are relative factors affecting the middle-term and short-term flexible function of knee joint after the fracture of patella, and short-term restoration can also be affected by whether surgery therapy or not. The effects of middle-term and short-term rehabilitation can be predicted by regression equation primarily.
文摘Two cases are presented of patients with a history of metastatic rectal adenocarcinoma presenting with a painful joint effusion. Both cases are potential examples of metastasis to periarticular bone with local infiltration to the synovium, which is one proposed mechanism of intrasynovial metastasis. While skeletal metastases are a relatively common occurrence in metastatic adenocarcinoma, intraarticular metastasis is extremely rare. These cases highlight the need to consider metastasis in the differential of joint swelling in the setting of a history of adenocarcinoma.
文摘Objective: To discuss a method to establish a three-dimensional model of healthy human knee joint, which can be used for further knee joint biomechanics analysis and simulation. Methods: CT scan and medical image three-dimensional reconstruction software (Mimics) were used to obtain the knee joint three-dimensional finite element model (FEM) according to reverse engineering theory. Results: FEM of knee joint with complete bone structure was established by Mimics. Conclusion: Three-dimensional FEM was established according to CT images exports as IGES file. The model can be used for knee joint biomechanics finite element analysis to provide references and proposals for the clinical diagnoses of knee joint illness, and the design of artificial knee joint prosthesis.
基金This study was supported by the German Research Foundation(DFG)(No.NE1953/1-1).
文摘Background Diffusion-weighted imaging(DWI)of synovitis has been suggested as a possible non-invasive alternative to contrast-enhanced T1w imaging(ce-T1w).We aimed to study DWI for diagnosing synovitis in the knee joint of pediatric patients,to quantify inter-observer agreement on DWI and ce-T1w and to calculate quantitative measures of synovial diffusivity and conspicuity.Methods Forty consecutive patients with known or suspected arthritis of the knee(25 girls,median age 12 years)underwent routine 1.5T MRI with ce-T1w and transverse DWI with b values 50 and 800 s/mm2.Mean apparent diffusion coefficient(ADC)values and signal intensity of inflamed synovium,joint effusion and muscle were measured with regions of interest retrospectively.Post-contrast T1 w images(diagnostic standard)and diffusion-weighted images at b=800 s/mm2 with ADC map were separately rated by three independent and blinded readers with different levels of expertise for the presence and degree of synovitis along with the level of diagnostic confidence.Results Thirty-one(78%)patients showed at least some synovial contrast enhancement,17(43%)children were diagnosed with synovitis on ce-T1w.Ratings by the 1st reader on ce-T1w and on DWI for synovitis showed very good agreement(kappa=0.90).Inter-observer agreement on DWI ranged from moderate to substantial with kappa values between 0.68 and 0.79(all P<0.001).Agreement and diagnostic confidence were generally lower in patients with mild and without synovial enhancement,compared to patients with synovitis.DWI yielded higher signal of inflamed synovium vs.muscle tissue,but lower signal vs.joint effusion,compared to ce-T1 w(all P<0.001).Conclusions Diffusion-weighted imaging is a promising,though reader-dependent alternative to contrast-enhanced imaging in patients with arthritis of the knee,based on our preliminary findings.It holds potential for increasing patient safety and comfort.
基金This study is sponsored by the National Natural Science Foundation project(51304076)of Chinait is supported by Hunan Provincial Department of Education Scientific Research Project(17C0863).
文摘In order to study the three jump training and competition on knee joint impact damage degree,left knee joint of one healthy male athletes is used as the research object,a complete knee three-dimensional model was established based on the jumper’s knee CT scan and magnetic resonance imaging(MRI),including the femur,tibia,fibula,patella and knee major cartilage,ligaments.The multi-body dynamics analysis(MDA)and finite element analysis(FEA)method are used to calculate the three jump,jump starting,landing process of athletes knee joint impact,the state should change the status of stress,strain and displacement.The results show that in the three jump process,the load on the lateral contact area of the knee joint is the largest,the displacement is the largest,and it increases with the impact of jump and landing.This exacerbated the degree of wear and tear of the tibia,it tends to induce knee injury in athletes.The results show that the combination of finite element and MDA can better study the knee joint’s shock and vibration during the three-level jump training and competition,and these open up a new research method for the knee joint injury.It also provides a certain reference for the prevention and treatment of knee joint injury.
