Joint Endoprosthetics Research Articles

Pathologies of joint endoprostheses : Histopathological diagnostics for endoprosthetic centers

Joint endoprosthetics is one of the most successful surgical-orthopedic procedures worldwide, enabling pain reduction and complete restoration of mobility. In the Federal Republic of Germany, around 400,000 joint endoprostheses, hip and knee joints are currently implanted every year ( https://www.eprd.de/de ) and around 30,000 replacement operations or revisions are carried out. Although there is constant optimization in the various technical and medical sectors of material development, construction, antibiotic therapy strategies, and surgical methodology of surgical joint replacement, factors that reduce service life and avariety of prosthesis-associated pathologies still exist. For implant revisions, the SLIM consensus classification, which is internationally accepted in the scientific literature, should be applied. The revised version of the SLIM consensus classification defines acomprehensive etiological spectrum of local joint endoprosthesis-associated pathologies histopathologically using ninetypes. In addition, this includes particle characterization and differentiation from endogenous particles. The analysis of the removed explant is the task of technical disciplines. Their mechanical and physical tests can provide information on the cause of the damage. For example, an examination of the fracture surface can determine whether the fracture occurred over alonger period of time (fatigue fracture, sustained fracture) or whether it occurred suddenly (forced fracture). It is therefore important to note that this diagnosis is carried out in an interdisciplinary manner, particularly in the context of peri-implant, mostly bacterial infections, and in the case of primarily functional and material-related causes. This interdisciplinary approach is particularly necessary for complex endoprosthesis pathologies, which require precise causal and technology-based damage analysis. In addition to histopathology, definitive diagnosis is only possible in aclinical-orthopedic, microbiological, laboratory medicine-related, radiological, nuclear medicine-related, material-technical and, in particular, biomechanical-technical context.

Knee joint endoprosthetics for rheumatoid arthritis

Determination of the immediate outcomes of disease course, preparation for surgery and treatment during knee joint endoprosthetics of patients with rheumatoid arthritis.

Aspects of the Combined Use of Anticoagulant and Hemostatic Drugs in Large Joint Endoprosthetics

The article presents a brief overview of the modern view on the problem of the combined use of drugs with a multidirectional spectrum of action, anticoagulants and hemostatics, in major orthopedics among patients with endoprosthetics of large joints of the lower extremities. Variable prescription regimens of anticoagulant prophylaxis against the background of using hemostatic drugs were analyzed.

OUTCOMES OF SHOULDER JOINT ENDOPROSTHETICS AFTER REMOVAL OF TUMORS IN THE HUMERUS

Introduction. The use of endoprostheses of the shoulder joint is possible with primary and secondary (metastatic) tumor lesions of the proximal part of the humerus. The possibility of using both individual oncological endoprostheses and modular oncological endoprostheses for tumors of the proximal part of the humerus is reported. Aim. To assess the effectiveness of restoring the function of the shoulder joint and upper limb and improving the patient's quality of life after shoulder joint arthroplasty for tumors of the proximal part of the humerus. Materials and methods. The results of the treatment of 27 patients who underwent shoulder arthroplasty in the conditions of the clinical departments of the "Institute of Traumatology and Orthopedics of the National Academy of Medical Sciences of Ukraine" for tumors of the proximal part of the humerus from 2014 to 2024 were evaluated. Endoprosthesis was performed in 22 (81.5%) patients with primary tumors of the proximal part of the humerus and in 5 (18.5%) with metastatic tumors. Endoprosthesis of the shoulder joint was performed with individual oncological endoprostheses in 24 (88.9%) patients and modular oncological endoprostheses in 3 (11.1%) patients. Arthroplasty was primary in 25 (92.6%) patients and secondary in 2 (7.4%) patients. Results. During follow-up, 3 (11.1%) patients died with an average follow-up period of 10.3±1.9 months, the other 24 (88.9%) were alive, with an average follow-up period of 88.1±8.7 months. The overall frequency of complications in our study was 6 (22.2%) cases, 3 (11.1%) patients had an infectious complication in the late postoperative period after 12, 24 and 36 months, 1 (3.7%) patient had aseptic loosening of the leg of the endoprosthesis after 36 months, in 2 (7.4%) patients after 5 and 6 months, dislocation of the head of the endoprosthesis from the joint cavity was noted. Local tumor recurrence was observed in 2 (7.4%) patients. The overall mean MSTS total limb functional outcome after shoulder arthroplasty for all 27 patients was 74.2%, and of the 24 patients who survived, the mean limb functional outcome after shoulder arthroplasty was 78.4%. The patients' quality of life (according to the EORTQ-QLQ-С30 questionnaire) increased from 32 points in the preoperative period to 78 points after shoulder joint replacement. Conclusions. Endoprosthetics is a modern method for reconstructing bone segments in the surgical treatment of tumors of long bones in the limbs. This method allows for the replacement of bone defects of any size (volume) and length. Shoulder joint endoprosthetics within the framework of combination and multimodal treatment of primary and metastatic tumors of the proximal part of the humerus provides restoration of both shoulder joint functions and the upper limb as a whole, thereby improving the quality of life for this group of patients.

Application of non-drug methods in rehabilitation programs to improve the quality of life of patients after lower limb joint endoprosthetics

BACKGROUND: All over the world, osteoarthritis is a common disease and accounts for 10% of all diseases in the population, and therefore, the frequency of large joint arthroplasty continues to increase, which determines the need to develop new methods of complex treatment in the rehabilitation of patients after arthroplasty operations.
 AIM: Scientific substantiation of the expediency of the complex use of a stabilometric multifunctional platform with biofeedback and light therapy in patients after arthroplasty of the joints of the lower extremities to improve the quality of life in the late recovery period.
 MATERIAL AND METHODS: 60 patients were examined three months after total joint replacement of the lower limb at the age of 55 to 75 years. All patients were randomly divided into three groups of 20 people comparable in terms of clinical and functional characteristics. Patients of the main group were exposed to monochromatic polarized incoherent light and underwent physical training using a stabilometric complex with biofeedback COBS (mtd-Systems, Germany), in the comparison group, patients received therapeutic exercises on a stabilometric simulator with biofeedback, patients the control group received only a standard rehabilitation complex and drug therapy, which served as a background in the main group and the comparison group.
 RESULTS: Prior to the start of treatment, when analyzing the indicators of static and dynamic stabilometric studies, an uneven distribution of the load was established during tests with a preponderance towards the healthy leg. After a course of treatment, patients of all groups showed statistically significant positive results, however, a more pronounced improvement in indicators was observed in patients of the main group, less pronounced, but statistically significant results were obtained in the comparison group, and insignificant positive dynamics was noted in patients of the control group. When studying the quality of life and the effectiveness of treatment according to the EQ-5D questionnaire in the examined patients in the initial state, the indicator averaged 6.60.8 points. After the course of treatment, patients of the main group showed a statistically significant decrease in the scores of the EQ-5D questionnaire from 6.70.9 points in the initial state to 4.20.9 (p 0.001), which lasted up to 6 months. In patients of the comparison group, in all periods of observation, a decrease in the indicator was also noted, but less pronounced, in patients of the control group ― only a positive trend. The findings were supported by the results of the Hospital Anxiety and Depression Scale (HADS).
 CONCLUSION: The use of a comprehensive rehabilitation program with the inclusion of a stabilometric platform with biofeedback and polarized light "Bioptron" contributes to a marked improvement in the state of balance, balance and coordination abilities of patients, normalization of muscle tone, a significant reduction in anxiety and depression and can significantly improve the quality of life of patients with endoprostheses in the late recovery period.

Rehabilitation Diagnosis Based on the International Functioning Classification (ICF) in Patients under Lower Limb Joint Endoprosthetics

To date, the introduction of the International Classification of Functioning, Disability and Health (ICF) into the practical work of rehabilitation institutions and units of different levels and different profiles is a key moment in the organization of the rehabilitation process in accordance with a new legislative framework and a new model of the medical rehabilitation system being created in Russia. Namely, the ICF is the basis for the rehabilitation diagnosis formulation as well as rehabilitation goals and the development of the rehabilitation strategy for each individual patient, and the practical ICF use presents the greatest difficulties for members of the multidisciplinary rehabilitation team (MDRT), since it requires to restructure their thinking stereotypes and behavior « from dysfunction – to limitation of activity», «from correction of disorders to restoration of activity». In this regard, the ICF usage issues in the process of rehabilitation of patients who underwent arthroplasty of large joints, presented in this article, are very relevant. Aim. To describe the most frequent ICF domains used in the formulation of a rehabilitation diagnosis in patients who have undergone the lower limb joints replacement. Conclusion. Identification of key problems based on ICF in patients undergoing total knee and hip arthroplasty allows a more focused and specialized approach to the rehabilitation process for this category of patients, correct formulation of rehabilitation goals and drawing up a plan of rehabilitation measures. In patients who have yet to undergo joint replacement, the use of classification allows to clarify the indications for surgical intervention.

Perioperative pharmacotherapy for endoprosthetics: potential of chondroitin sulfate and glucosamine sulfate

Joint endoprosthetics is a treatment of choice for patients with decompensated osteoarthritis (OA), who have exhausted the possibilities of pharmacotherapy and other methods of conservative treatment. Preparation for endoprosthetics and rehabilitation after surgery usually includes measures to improve the muscle condition and local blood circulation in the joint area, and if necessary, pain management. The unique spectrum of anti-inflammatory effect of chondroprotectors based on chondroitin sulfate and glucosamine sulfate includes inhibition of NF-κB cascade, toll-like receptors, pro-inflammatory cytokines, metalloproteinases, and significantly alleviates the course of OA. Reducing the severity of OA is important for preparing for surgery, subsequent rehabilitation, and preventing the revision surgery.

Kinesiophobia in patients requiring hip and knee endoprosthetics: severity and provoking factors

To study the severity and risk factors of KP in patients requiring total hip and knee endoprosthetics (EP). We examined 50 patients requiring total EP of the hip and knee joints. Pain syndrome was assessed in the preoperative and early postoperative periods in all patients using a visual analog scale, as well as the levels of kinesiophobia, anxiety, and depression using the Hospital Anxiety and Depression Scale and the Tampa Scale for Kinesiophobia (TSK). Quality of patients life was studied in the preoperative period (RAND SF36 questionnaire). In the majority of cases, both before and after EP, the level of KP corresponded to an average degree of severity. Both in the preoperative and in the early postoperative periods, not a single case of the absence of KP was detected (≤17 points according to the TSK); at the same time, a very high level of KP (≥55 points according to TSK) was also rarely recorded - in 3 patients in the postoperative period after EP of the hip joint. KP level significantly correlated with the duration of the pain syndrome, while the mental component of the KP, in addition to the duration of the pain syndrome, was influenced by the social status: in patients who had a steady job, the psychological component of the KP was expressed in a less degree. KP level was negatively correlated with such indicators of quality of life as vitality and physical functioning. In addition, the physical component of the KP significantly correlated with the pain intensity, the mental component - with role-playing behavior. Early detection of KP and timely correction of distorted ideas about physical activity are necessary for successful rehabilitation of patients requiring total joint endoprosthetics of the lower limb.

Влияние сопутствующей патологии на характер и частоту послеоперационных осложнений при эндопротезировании тазобедренного сустава

The number of major joint endoprosthetics is growing every year. Hip replacement is the most performed of all. A lot of practical experience has been accumulated in this area and there is a constant improvement of operational equipment, new implants and other materials are being developed, as well as the qualifications of operating surgeons are growing. However, despite this, the number of complications after hip replacement surgery remains high. This is largely due to the uncompensated comorbidity among patients, especially in the elderly and senile age. The aim of our research was to study the effect of the comorbidity presence among patients on the nature and frequency of postsurgical complications during hip replacement surgeries. We analyzed the results of hip replacement using the IRENE Diamond implant among 405 patients for the period from January 2020 to April 2021. As a result of the study, it was found that the greatest number of purulent-septic complications were in patients with rheumatoid arthritis. The presence of other comorbidities in patients equally affected the number and nature of postsurgical complications.

Analgesic efficacy of continuous intravenous infusion of morphine in patients after hip and knee joint endoprosthetics: prospective study

Objectives of the study was to evaluate the possibility of using and the frequency of side effects of continuous intravenous morphine infusion for patients after arthroplasty of the lower limbs joints. Materials and methods. In the prospective study the results of treatment of 2 groups of patients were compared: after total knee arthroplasty (n = 52) and after total hip arthroplasty (n = 52). The rate of morphine administration in the total knee arthroplasty group ranged from 0.6 to 1.6 mg/hour, in the total knee arthroplasty group it was from 0.4 to 1.4 mg/hour. Continuous infusion of morphine was continued 24 hours after surgery. Indicators of systemic hemodynamics, gas exchange, pain and sedation were recorded. Results. The use of the technique of continuous intravenous infusion of morphine has shown the adequate level of anesthesia. An optimal balance between adequate analgesia, sedation and the absence of respiratory depression can only be achieved through a low rate of morphine administration. There was no significant difference in the incidence of complications and side effects (nausea, vomiting, acute urinary retention, delirium) in the groups with knee and hip arthroplasty. Conclusion. The technique provided, on the one hand, a good analgesic effect and sedation, but on the other hand, it was quite laborious and required careful monitoring of the parameters of the respiratory and cardiovascular systems. It is especially necessary to carefully monitor the indicators of vital functions in the evening and night hours.

Assessment of clinical efficacy of the acoustic binaural beating method in the complex preparation of patients for hip replacement

Objective. To increase the efficiency of the complex of therapeutic and rehabilitation measures in preparation for hip joint endoprosthetics.
 Materials and methods. 66 patients in whom it was planned to perform hip joint endoprosthetics took part in the research. They were divided into two groups. The main group (n = 32) included patients who underwent 5 binaural beats as a relaxation program. In the comparison group (n = 34) the patients received a standard set of measures to prepare for this operation. All patients were screened for depression and anxiety using the standardized hospital scale for anxiety and depression (HADS) before the study. We also recorded the initial levels of reactive and personality anxiety using the Spielberger Hanin test. We repeated the test in both groups after 7 days to evaluate the dynamics of the test.
 Results. The conducted research showed that in the main group on the background of binaural beating procedures, reactive (from 57.2 3.8 to 42.4 5.2 points, p = 0.014) and personal anxiety (from 58.9 4.1 to 44.7 3.8 points, p = 0.003) were significantly reduced. In addition, the application of binaural beats method resulted in a significant decrease of HADS alarm subscale indexes (p 0.001) in patients of the base group from 12.8 2.8 to 8.5 0.7 points. While patients in the comparison group had significantly less expressed decrease of this parameter from 11.7 3.1 to 10.9 1.6 points (p 0.01). On the HADS depression subscale there was also a marked decrease in the main group to 7.1 0.8 points, this value was statistically significantly lower (p = 0.011) than in the comparison group 10.2 1.2 points.
 Conclusion. The conducted research has shown that the use of the binaural beats method in the complex of measures to prepare patients for hip joint endoprosthetics helps to improve their psycho-emotional status. This is manifested by a decrease in personal and reactive anxiety in the Spielberger Hanin test, as well as the severity of depression and anxiety on the HADS scale. The advantages of the method are non-invasive and easy to use, and the disadvantages include the duration of the procedure and poorly studied mechanism of action.

Immunological aspects of carbohydrate and lipid metabolism in patients with periprosthetic infection and osteomyelitis

A study of carbohydrate and lipid metabolism and immunological examination of patients with periprosthetic infection after knee and hip joint endoprosthetics (n = 16) and osteomyelitis (n = 20) was conducted. The patients with periprosthetic infection were characterized by anemia, eosinophilia, impaired glucose tolerance, cholestasis, predisposition to elevated atherogenesis, increased circulating immune complexes, autoimmune granulocytotoxic antibodies, immunoglobulins IgM, IgG, IgA and sensitization to synovial membrane and Staphylococcus aureus. The patients with osteomyelitis did not develop increased glucose and cholesterine level, but showed increased aminotransferases, thymol test, chondroitinsulfates, decrease of calcium and production of the leukocyte migration inhibition factor (LIF), both non-specific and to the antigens of cartilage tissue and sensitization to Streptococcus and E. coli. In patients with infections of the musculoskeletal system, glucose metabolism disturbances have been associated with the presence of autoimmune lymphocytotoxic antibodies, reduced production of LiF, both non-specific and to the antigens of synovial membrane. Atherogenesis was associated with increased circulating immune complexes, autoimmune lymphocytotoxic and granulocytotoxic antibodies, decreased LIF and sensitization to connective tissue antigens and pathogenic microorganisms, especially to Streptococcus and Proteus. Anemia was associated with increased autoimmune lymphocytotoxic antibodies, delayed-type sensitization to bone and cartilage tissue, to Staphylococcus and sensitization by accelerated type to E. coli and Proteus. Physicians should analyse immunological data while treating and monitoring the patients with connective tissue infections and disturbances of glucose and cholesterine metabolism.

Физиотерапевтическое обеспечение пациентов с диспластическим коксартрозом после тотального эндопротезирования тазобедренного сустава

Today, the main method of surgical treatment of dysplastic coxarthrosis among adults is total hip prosthetics. Distant positive results according to foreign authors are 76–89%. One method of rehabilitation is physiotherapeutic treatment. The absence of standardized physiotherapeutic treatment protocols leads to a sharp reduction in the prescription of this type of rehabilitation measures. The aim of the study is to assess the long-term results of hip joint endoprosthetics among patients with dysplastic coxarthrosis using the developed physiotherapeutic treatment technique. Research materials and methods. For the period from 2010 to 2014, 205 patients were performed an operation with dysplastic coxarthrosis 1, 2, 3 degrees of Crowe. In the pre- and postoperative periods, patients of the main group were prescribed physiotherapeutic treatment according to the developed methodology. Evaluation of the results was carried out 12 months after surgical treatment using clinical and radiological methods, questionnaires using the Harris scale, SF-36. The obtained data were processed using statistical methods: Student coefficient, Pearson coefficient, correlation method. Results. When analyzing distant results, the average Harris score in the main group 85.82 (84.93–86.71) was significantly higher than in the comparison group 83.01 (82.02–84.00). The average score of the SF-36 questionnaire in the main group was significantly higher than in the comparison group (p < 0.001). Mental health indicators of patients were not significantly different from those of the postoperative period and were at a high level. Conclusions. Prescription of physiotherapeutic treatment promotes rapid healing of postoperative wounds and improves results of surgical treatment.

Effect of age on the functioning of hemostasis system during hip joint endoprosthesis

The study was performed on 109 osteoarthritis patients who underwent hip joint endoprosthetics; the effect of age on changes in hemostasis system, blood loss level and deep veins thrombosis development in the background of standard prevention with low-molecular heparins were studied. Before the surgery, it was determined that 56 elderly patients (60.3 ± 6.4 years) compared to 53 middle-aged patients (41.8 ± 6.8 years) had a significantly higher initial and postoperative endothelial dysfunction, higher fibrin formation and lower anticoagulant potential; however, it was found that on the background of pharmacological anticoagulant therapy the changes in the hemostasis functioning in elderly patients did not lead to an increase of either blood loss or the number of thromboses.

Физиотерапевтическое обеспечение пациентов c диспластическим коксартрозом после тотального эндопротезирования тазобедренного сустава

Today, the main method of surgical treatment of dysplastic coxarthrosis among adults is total hip prosthetics. Distant positive results according to foreign authors are 76–89%. One method of rehabilitation is physiotherapeutic treatment. The absence of standardized physiotherapeutic treatment protocols leads to a sharp reduction in the prescription of this type of rehabilitation measures. The aim of the study is to assess the long-term results of hip joint endoprosthetics among patients with dysplastic coxarthrosis using the developed physiotherapeutic treatment technique. Research materials and methods. For the period from 2010 to 2014, 205 patients were performed an operation with dysplastic coxarthrosis 1, 2, 3 degrees of Crowe. In the pre- and postoperative periods, patients of the main group were prescribed physiotherapeutic treatment according to the developed methodology. Evaluation of the results was carried out 12 months after surgical treatment using clinical and radiological methods, questionnaires using the Harris scale, SF-36. The obtained data were processed using statistical methods: Student coefficient, Pearson coefficient, correlation method. Results. When analyzing distant results, the average Harris score in the main group 85.82 (84.93–86.71) was significantly higher than in the comparison group 83.01 (82.02–84.00). The average score of the SF-36 questionnaire in the main group was significantly higher than in the comparison group (p < 0.001). Mental health indicators of patients were not significantly different from those of the postoperative period and were at a high level. Conclusions. Prescription of physiotherapeutic treatment promotes rapid healing of postoperative wounds and improves results of surgical treatment.

Pre-Surgery Planning of Lower Limbs Major Joints Arthroplasty.

BACKGROUND:Knee and hip joints endoprosthetics are the main surgical method of arthrosis treatment. The epidemiological incidence rate of the disease is growing steadily every year, affecting younger and younger people. Despite the proven tactics of joint endoprosthetics, an important issue is quality planning of surgery.AIM:The aim of this research is to develop a device and a method that would contribute to solving the existing challenges of pre-surgery planning of hip endoprosthetics in patients with related pathologies, which have caused compensatory deformation, and making long vertebrarium-pelvis-lower limbs scout images with the patient lying on his back with an axial load in a computer tomography.METHODS:Analog X-ray photographs of the pelvis made on film, digital DICOM images, and special planning programs are used for planning. However, according to numerous studies, the disease of the hip joint is not an independently isolated pathology. In most cases, this pathology is accompanied by changes in the lumbar spine. Often, patients prepared for endoprosthetics have a congenital deformity of tarsus or hip segment, which, during the knee, joint endoprosthetics surgery causes difficulties with the installation of an intramedullary guide.RESULTS:The results after total knee arthroplasty according to the method modified at the Department showed a reduction of the WOMAC index slightly more than twice down to 37.26 ± 7.92. The number of revision surgeries after endoprosthetics decreased from 5 (5.7%) to 1 (1.1%) for the hip joint, and from 7 (4.3%) to 2 (1.3%) for the knee joint, respectively.CONCLUSION:To form a proper guide entry point, it is necessary to assess the segment at the stage of surgery planning and examination of patients, which can be done using the proposed method. To remove the complications during the pre-surgery planning of hip joint endoprosthetics in patients with related pathologies, a device and methods have been developed for obtaining long topograms of the vertebrarium-pelvis-lower limbs complex with the patient lying on his back with the axial load in computer tomography.

Infusion prevention of fat globulaemia during total hip arthroplasty

To assess the effect of the modified infusion therapy regimen on the frequency of development of laboratory and clinical manifestations of fat embolism syndrome in patients after hip replacement. The study was conducted in 80 patients (70 men and 10 women) who were admitted for planned revision hip arthroplasty. The criteria for not inclusion in the study were the presence of a traumatic brain injury, episodes of acute disturbance of blood supply (stroke) and diabetes mellitus in history. 40 patients of the main group during the operation were administered Gelofuzin and Sterofundin isotonic, and in the first day after the operation Remaxol and Sterofundin isotonic. Using the copy-steam method, a control group (n=40) out of 197 patients was selected by gender and age. In the control group, infusion therapy was carried out using a 0.9% NaCl solution. All patients underwent assessment of fat globulemia, water-electrolyte balance, acid-base status and oxygenation index - before surgery; 2, 24, 48, and 72 hours after the operation, on the third day, mental disorders were assessed using the Addenburg scale (ACE-R) for evaluating cognitive functions. All patients underwent hip joint endoprosthetics. In the group receiving the modified infusion therapy regimen, the results were significantly better, there were no statistically significant changes in the level of electrolytes (p=0.14), episodes of a decrease in the oxygenation index and cognitive dysfunction. In contrast to patients in the control group, where the level of chlorine and sodium was significantly higher, the number of fat globules with a diameter of more than 8 μm, as well as in two patients, the development of postoperative delirium with a decrease in the oxygenation index below 300 was observed. The causal relationship between the number of fat globules with a diameter of more than 8 microns and clinical manifestations of cerebral and pulmonary forms of fat embolism (r-Pirsen = -0.87 and -0.80, respectively). There were no statistically significant changes in platelet count, potassium concentration with indicators of fat globulemia and a scale of cognitive impairment. A high correlation of fatty globulemia with the development of respiratory and pulmonary dysfunction after hip replacement was determined. The inclusion of Gelofuzin, Sterofundin isotonic and Remaxol in intensive therapy provides a pronounced emulsifying effect on fat globules appearing in the bloodstream in the first hours after hip replacement, and effective prevention of potentially dangerous fat embolism.

The spectrum of histomorphological findings related to joint endoprosthetics

Approximately 230,000 total hip and 170,000 knee joint endoprostheses are implanted in Germany annually of which approximately 10% (i.e. 40,000 interventions per year) are cases of revision surgery. These interventions involve removal of a previously implanted prosthesis which has resulted in complaints and replacement with a new prosthesis. There are manifold reasons for revision surgery, the most common indication being so-called endoprosthesis loosening, which is subdivided into septic and aseptic loosening. Histomorphological studies revealed that periprosthetic tissue from endoprosthesis loosening can be classified into four types (I) wear-particle induced type, (II) infectious type, (III) combined type and (IV) fibrous type. Types I and IV represent aseptic loosening and types II and III septic loosening. Recently, the topic of implant allergy has emerged. The detection of cellular, mostly perivascular lymphocytic infiltrates is discussed as being a sign of an allergic tissue reaction. It has most frequently been observed in type I periprosthetic membranes with a dense load of metal wear, which occurs with metal-on-metal bearings. Apart from endoprosthesis loosening, arthrofibrosis is another complication of joint endoprosthetics and can cause pain and impaired function. Histopathologically, arthrofibrosis can be evaluated by a three-tiered grading system. Furthermore, bone pathologies, such as ossification, osteopenia or osteomyelitis can occur as complications of joint endoprosthetics. This review gives an overview of the whole spectrum of pathological findings in joint endoprosthetics and offers a comprehensive and standardized classification system for routine histopathological diagnostics.

Analysis of the results of the knee joint endoprosthetics in patients with rheumatoid arthritis

Proceeding from the analysis of treatment of 78 patients with rheumatoid arthritis who underwent 104 operations of the total knee joint arthroplasty, the authors studied anatomical-functional changes in the knee joint and the injured limb, and singled out the main factors, which produce their effect of the arthroplasty result. It was found out that flexion contracture of the knee joint occurred in 62.5 % of cases, and axial deformity in 43.27 %, with more than 20° in 9.62 %. A system of preparation for knee joint arthroplasty was developed. The above system includes elimination of the flexion contracture in the knee joint by stage-by-stage redressments with application of plaster bandages and using Volkov-Oganesian device for stable contractures. The technique of arthroplasty for cases of rigidity and ankylosis in the knee joint was improved; bone defect autoplasty was used for those bones, which form the knee joint. The suggested system for preparing patients for arthroplasty and the improved technique of the knee joint arthroplasty make it possible to eliminate the flexion contracture, thereby avoiding excessive resection of the bone joint ends during the operation and preventing complications in the neurovascular bundle in the postoperative period.

Der Einfluss der Knochenmineraldichte und des Verankerungsverfahrens auf die Primärstabilität von zementfrei implantierten Tibiakomponenten / The influence of bone quality and the fixation procedure on the primary stability of cementless implanted tibial plateaus

An overview of prospective studies on cementless and cemented primary knee joint endoprosthetics carried out between 1988 and 2004 reveals that the aseptic tibial loosening rate of cemented prostheses implanted with fixed meniscal bearings amounts to 2-6% within a period of 4-14 years, while cementless implanted prostheses show loosening rates of up to 28% within a period of 4-10 years. If these results arise from a lack of proper initial osseointegration as a result of insufficient primary stability, and how this is influenced by the tibial bone quality and the tibial fixation procedure has not yet been investigated. Tibial plateaus were press-fit implanted, both screwed and unscrewed, into each of six pairs of tibial heads from corpses. Stability testing was conducted applying eccentric axial load, shear and torsion. The average amounts of relative movement at the medial and lateral plateau are clearly different in the screwed version and the unscrewed version when loaded axially, but the difference was significant (p = 0.016) only at the medial plateau. Relative movements under shear and torsion showed no significant differences. The bone density of the tibial metaphyses had no significant effect on the primary stability of the cementless implanted tibial plateau. When using cementless knee endoprostheses, the fixation of the tibial plateau with screws--in addition to a flawless press-fit and form-fit customization of the tibial head--appears indispensable for guaranteeing proper osseointegration under physiological axial loads.