计算机辅助全膝置换中股骨力线定位精度的实验研究

摘要利用光学定位追踪仪确定全膝置换中患者的股骨头中心从而确定其股骨力线，在力线的定位精度分析中，首次采用股骨的三维重建模型进行精度校验。实验结果表明通过追踪固定于股骨末端的刚性定位器即能确定精确的股骨力线，与传统的髓内定位相比，不仅可重复性好，而且大大地提高了术中股骨力线的位置精度，将其位置偏差减小到10以内。     

Chondral separation in the trochlear groove - a definite clinical entity

Four patients with unusual femoro-patellar chondral defects are presented. We were unable to find their particular lesion described adequately in the literature. The patients all gave a history of relatively minor non-contact injury and presented with anterior knee pain and persistent swelling. The main features on clinical examination were moderate effusion and marked patello-femoral crepitus. Plain X-rays of the knee were unhelpful. At arthroscopy large full thickness chondral defects were seen on the femoral side of the patello-femoral articulation at the site of patellar contact with the knee in about 60° of flexion. The synovium was found to be prolific and vascular. Multiple 1.6-mm drill holes were made in the defect and chondral debris was washed out. Two patients underwent associated lateral patellar release. When a clear cut mechanical patello-femoral disorder presents unexpectedly with associated effusion and a normal radiograph, we suggest that arthroscopy be advised with particular attention to the femoral trochlea.     

Approximately 80% of Japanese osteoarthritic patients fall out of the safety range in restricted kinematically-aligned total knee arthroplasty in an analysis of preoperative long-leg radiograms

BackgroundRestricted kinematically-aligned total knee arthroplasty (KA-TKA) is a reasonable modification to avoid the alignment outlier that may cause implant failure. However, despite a noted high incidence of constitutional varus in Japanese individuals, there has been no investigation into how many knees require the restriction in restricted KA-TKA (RKA-TKA) among Japanese patients. Therefore, we conducted a study using preoperative long-leg radiograms.MethodsWe studied long-leg radiographs of 228 knees in 114 consecutive patients. The numbers of knees within the safety range and their corrective osteotomy angle in the restriction algorithms advocated by Almaawi et al. (2017) and MacDessi et al. (2020) were evaluated.ResultsAccording to the algorithms used by Almaawi et al. and MacDessi et al., out of 228 knees, 46 (20%) and 39 (17%) fell within the safety range, respectively. The mean correction angles of the hip-knee-ankle angle, lateral distal femoral angle and medial proximal tibial angle were 2.8 ± 3.4°, 0.4 ± 1.4° and 2.4 ± 2.8° in the algorithm used by Almaawi et al., while they were −4.9 ± 4.7°, 1.1 ± 2.5° and −6.0 ± 3.4° in the algorithm used by MacDessi et al. Most of the knees needed to be restricted in order to perform RKA-TKA, regardless of the algorithm used.ConclusionsBased on a preoperative analysis of long-leg radiograms in a Japanese population, most knees fall out of the safety range in RKA-TKA. Surgeons must consider whether to allow component outlier or to perform corrective osteotomy that likely requires soft tissue release.     

膝关节韧带的生物力学研究进展

膝关节韧带的生物力学是近年来研究的热点之一,力学刺激对调控韧带功能、韧带组织愈合和重建有着重要的作用,作者从膝关节韧带的结构、力学与生化特点、愈合与重建、施加应力与制动对韧带的影响、应力对韧带细胞分化的影响和前交叉韧带与内侧副韧带的对比研究等方面综述了近年来的一些研究进展。     

Dietary Interventions with Polyphenols in Osteoarthritis: A Systematic Review Directed from the Preclinical Data to Randomized Clinical Studies

Osteoarthritis (OA) is the most common form of arthritis and a major cause of limited functionality and thus a decrease in the quality of life of the inflicted. Given the fact that the existing pharmacological treatments lack disease-modifying properties and their use entails significant side effects, nutraceuticals with bioactive compounds constitute an interesting field of research. Polyphenols are plant-derived molecules with established anti-inflammatory and antioxidant properties that have been extensively evaluated in clinical settings and preclinical models in OA. As more knowledge is gained in the research field, an interesting approach in the management of OA is the additive and/or synergistic effects that polyphenols may have in an optimized supplement. Therefore, the aim of this review was to summarize the recent literature regarding the use of combined polyphenols in the management of OA. For that purpose, a PubMed literature survey was conducted with a focus on some preclinical osteoarthritis models and randomized clinical trials on patients with osteoarthritis from 2018 to 2021 which have evaluated the effect of combinations of polyphenol-rich extracts and purified polyphenol constituents. Data indicate that combined polyphenols may be promising for the treatment of osteoarthritis in the future, but more clinical trials with novel approaches in the identification of the in-between relationship of such constituents are needed.     

Impact of Sarcopenia and Obesity on Gait Speed After Total Knee Replacement

ObjectivesOlder adults with sarcopenic obesity have a higher risk of experiencing mobility difficulty. Additionally, sarcopenia and obesity are closely associated with knee osteoarthritis. This study investigated the associations of sarcopenia, obesity, and in combination of both with walking disability during postoperative rehabilitation in older adults with knee osteoarthritis who underwent total knee replacement.DesignA retrospective cohort study.Setting and ParticipantsFrom a rehabilitation center database, we retrospectively selected and investigated 482 older patients with knee osteoarthritis who had undergone total knee replacement and received postoperative rehabilitation.MethodsSarcopenia was identified in accordance with the diagnostic criteria established by the Asian Working Group for Sarcopenia and obesity was defined as body mass index ≥ 30 kg/m². Accordingly, patients were classified into four body composition groups, namely sarcopenic obese, sarcopenic, obese, and normal (reference group). After total knee replacement, all patients attended monthly follow-up admission during the postoperative rehabilitation. Gait speed was measured before surgery and monthly after total knee replacement. A gait speed cutoff of 1.0 m/s was used to identify postoperative walking disability. Kaplan–Meier curve analysis was performed to measure the probability of experiencing postoperative walking disability among the groups. Cox multivariate regression models were established to calculate the hazard ratios of postoperative walking disability.ResultsCompared with the reference group, the sarcopenic, obese, and sarcopenic obese groups appeared to have a higher probability of experiencing postoperative walking disability (all P < .001). The sarcopenic obese group were likely to have the highest risk of experiencing postoperative walking disability (adjusted hazard ratio = 3.89).Conclusions and ImplicationsSarcopenia or obesity alone may independently exert negative effects on postoperative gait speed. The participants with sarcopenic obesity were likely to have the highest risk of experiencing walking disability following total knee replacement. The findings may serve as a reference for clinicians developing rehabilitation strategies to optimize walking ability after total knee replacement, especially those preoperatively diagnosed as having sarcopenic obesity.     

Feasibility of a self‐assembling peptide hydrogel scaffold for meniscal defect: An in vivo study in a rabbit model

The inner avascular zone of the meniscus has limited healing capacity as the area is poorly vascularized. Although peptide hydrogels have been reported to regenerate bone and cartilage, their effect on meniscus regeneration remains unknown. We tested whether the self‐assembling peptide hydrogel scaffold KI24RGDS stays in the meniscal lesion and facilitates meniscal repair and regeneration in an induced rabbit meniscal defect model. Full‐thickness (2.0 mm diameter) cylindrical defects were introduced into the inner avascular zones of the anterior portions of the medial menisci of rabbit knees (n = 40). Right knee defects were left empty (control group) while the left knee defects were transplanted with peptide hydrogel (KI24RGDS group). Macroscopic meniscus scores were significantly higher in the KI24RGDS group than in the control group at 2, 4, and 8 weeks after surgery. Histological examinations including quantitative and qualitative scores indicated that compared with the control group, the reparative tissue in the meniscus was significantly enhanced in the KI24RGDS group at 2, 4, 8, and 12 weeks after surgery. Immunohistochemical staining showed that the reparative tissue induced by KI24RGDS at 12 weeks postimplantation was positive for Type I and II collagen. KI24RGDS is highly biocompatible and biodegradable, with strong stiffness, and a three dimensional structure mimicking native extracellular matrix and RGDS sequences that enhance cell adhesion and proliferation. This in vivo study demonstrated that KI24RGDS remained in the meniscal lesion and facilitated the repair and regeneration in a rabbit meniscal defect model.     

Can Machine Learning Methods Produce Accurate and Easy-to-Use Preoperative Prediction Models of One-Year Improvements in Pain and Functioning After Knee Arthroplasty?

BackgroundApproximately 15%-20% of total knee arthroplasty (TKA) patients do not experience clinically meaningful improvements. We sought to compare the accuracy and parsimony of several machine learning strategies for developing predictive models of failing to experience minimal clinically important differences in patient-reported outcome measures (PROMs) 1 year after TKA.MethodsPatients (N = 587) in 3 large Veteran Health Administration facilities completed PROMs before and 1 year after TKA (92% follow-up). Preoperative PROMs and electronic health record data were used to develop and validate models to predict failing to experience at least a minimal clinically important difference in Knee Injury and Osteoarthritis Outcome Score (KOOS) Total, KOOS JR, and KOOS subscales (Pain, Symptoms, Activities of Daily Living, Quality of Life, and recreation). Several machine learning strategies were used for model development. Ten-fold cross-validation and bootstrapping were used to produce measures of overall accuracy (C-statistic, Brier Score). The sensitivity and specificity of various predicted probability cut-points were examined.ResultsThe most accurate models produced were for the Activities of Daily Living, Pain, Symptoms, and Quality of Life subscales of the KOOS (C-statistics 0.76, 0.72, 0.72, and 0.71, respectively). Strategies varied substantially in terms of the numbers of inputs required to achieve similar accuracy, with none being superior for all outcomes.ConclusionModels produced in this project provide estimates of patient-specific improvements in major outcomes 1 year after TKA. Integrating these models into clinical decision support, informed consent and shared decision making could improve patient selection, education, and satisfaction.Level of EvidenceLevel III, diagnostic study.     

Diagnostic Utility of Platelet Count/Lymphocyte Count Ratio and Platelet Count/Mean Platelet Volume Ratio in Periprosthetic Joint Infection Following Total Knee Arthroplasty

BackgroundDiagnosing a periprosthetic joint infection (PJI) can be challenging and often requires a combination of clinical and laboratory findings. Monocyte/lymphocyte ratio, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio (PLR), and platelet/mean platelet volume ratio (PVR) are simple predictors for inflammation that can be readily obtained from complete blood count. The aim of this study is to evaluate the diagnostic utility of these markers in predicting PJI in total knee arthroplasty (TKA) patients.MethodsA total of 538 patients who underwent revision TKA with calculable marker ratios prerevision in 2 groups were evaluated: (1) 206 patients with a preoperative diagnosis of PJI (group I) and (2) 332 patients treated for revision TKA for aseptic failures (group II). The diagnostic abilities of the markers were assessed via receiver operator characteristic curve analysis.ResultsThe optimal threshold of PVR at 30.82 had the highest sensitivity of 87.7%, while the optimal threshold of PLR at 234.13 had the highest specificity of 82.5%. Both PLR and PVR, when combined with Musculoskeletal Infection Society thresholds for erythrocyte sedimentation rate, C-reactive protein, synovial WBC, and PMN%, achieve significantly higher sensitivity and specificity rates for PJI at or above 97% (PLR: 99.03%; 98.80%; PVR: 98.54%;97.89%).ConclusionOur study demonstrates that PVR and PLR, which are readily available and inexpensive to obtain from complete blood counts, when combined with serum and synovial fluid markers have increased sensitivity and specificity comparable to that of alpha defensin. This suggests that PVR and PLR can be used together with other hematologic and aspirate markers to increase the accuracy of PJI diagnosis in TKA patients.     

Impact of Compensated Cirrhosis Etiology on Postoperative Outcomes Following Total Knee Arthroplasty

BackgroundCirrhotics often demonstrate worse outcomes than their non-cirrhotic counterparts following orthopedic surgery; however, there are limited arthroplasty-focused data on this occurrence. Additionally, variances in postoperative outcomes among the different etiologies of cirrhosis have not been well described. The aim of this study is to evaluate the effect compensated cirrhosis had on postoperative outcomes following elective total knee arthroplasty (TKA).MethodsIn total, 1,734,568 patients who underwent primary TKA from 2006 to 2013 were identified using the Medicare Claims Database. Patients were divided into those with a history of compensated cirrhosis and those with no history of liver disease. Subgroup analysis was performed based on the etiology of cirrhosis. Multivariate logistic regression was used to evaluate postsurgical outcomes of interest.ResultsCirrhotic patients had higher risk of developing disseminated intravascular coagulation (odds ratio [OR] 2.76, P = .003), encephalopathy (OR 3.00, P < .001), and periprosthetic infection (OR 1.79, P < .001) compared to controls. Following subgroup analysis, alcoholic cirrhotics had high risk of periprosthetic infection (OR 2.12, P < .001), fracture (OR 3.28, P < .001), transfusion (OR 2.45, P < .001), and encephalopathy (OR 7.34, P < .001) compared to controls. Viral cirrhosis was associated with an increase in 90-day charges ($14,941, P < .001) compared to controls, while cirrhosis secondary to other causes was associated with few adverse outcomes compared to controls.ConclusionLiver cirrhosis is an independent risk factor for increased perioperative morbidity and financial burden following TKA. Cirrhosis due to etiologies other than viral infections and alcoholism are associated with few adverse outcomes. Surgeons should be aware of these complications to properly optimize postoperative management.