Purpose
The purpose of this study was to determine the ideal coronal alignment under dynamic conditions after open-wedge high tibial osteotomy (OWHTO). It was hypothesised that, although the ...classical target alignment was based on experimental evidence, it would demonstrate biomechanical validity.
Methods
Musculoskeletal computer models were analysed with various degrees of coronal correction in OWHTO during gait and squat, specifically with the mechanical axis passing through points at 40%, 50%, 60%, 62.5%, 70%, and 80% of the tibial plateau from the medial edge, defined as the weight-bearing line percentage (WBL%). The peak load on the lateral tibiofemoral (TF) joint, the medial collateral ligament (MCL), and anterior cruciate ligament (ACL) tensions, and knee kinematics with or without increased posterior tibial slope (PTS) were evaluated.
Results
The classical alignment with WBL62.5% achieved sufficient load on the lateral TF joint and maintained normal knee kinematics after OWHTO. However, over-correction with WBL80% caused an excessive lateral load and non-physiological kinematics. Increased WBL% resulted in increased MCL tension due to lateral femoral movement against the tibia. With WBL80%, abnormal contact between the medial femoral condyle and the medial intercondylar eminence of the tibia occurred at knee extension. The screw-home movement around knee extension and the TF rotational angle during flexion were reduced as WBL% increased. Increased PTS was associated with increased ACL tension and decreased TF rotation angle because of ligamentous imbalance.
Conclusions
The classical target alignment demonstrated validity in OWHTO, and over-correction should be avoided as it negatively impacts clinical outcome.
Level of evidence
IV.
MicroRNAs (miRNAs), endogenous small noncoding RNAs regulating the activities of target mRNAs and cellular processes, are present in human plasma in a stable form. In this study, we investigated ...whether miRNAs are also stably present in synovial fluids and whether plasma and synovial fluid miRNAs could be biomarkers of rheumatoid arthritis (RA) and osteoarthritis (OA).
We measured concentrations of miR-16, miR-132, miR-146a, miR-155 and miR-223 in synovial fluid from patients with RA and OA, and those in plasma from RA, OA and healthy controls (HCs) by quantitative reverse transcription-polymerase chain reaction. Furthermore, miRNAs in the conditioned medium of synovial tissues, monolayer fibroblast-like synoviocytes, and mononuclear cells were examined. Correlations between miRNAs and biomarkers or disease activities of RA were statistically examined.
Synovial fluid miRNAs were present and as stable as plasma miRNAs for storage at -20 degrees C and freeze-thawing from -20 degrees C to 4 degrees C. In RA and OA, synovial fluid concentrations of miR-16, miR-132, miR-146a, and miR-223 were significantly lower than their plasma concentrations, and there were no correlation between plasma and synovial fluid miRNAs. Interestingly, synovial tissues, fibroblast-like synoviocytes, and mononuclear cells secreted miRNAs in distinct patterns. The expression patterns of miRNAs in synovial fluid of OA were similar to miRNAs secreted by synovial tissues. Synovial fluid miRNAs of RA were likely to originate from synovial tissues and infiltrating cells. Plasma miR-132 of HC was significantly higher than that of RA or OA with high diagnosability. Synovial fluid concentrations of miR-16, miR-146a miR-155 and miR-223 of RA were significantly higher than those of OA. Plasma miRNAs or ratio of synovial fluid miRNAs to plasma miRNAs, including miR-16 and miR-146a, significantly correlated with tender joint counts and 28-joint Disease Activity Score.
Plasma miRNAs had distinct patterns from synovial fluid miRNAs, which appeared to originate from synovial tissue. Plasma miR-132 well differentiated HCs from patients with RA or OA, while synovial fluid miRNAs differentiated RA and OA. Furthermore, plasma miRNAs correlated with the disease activities of RA. Thus, synovial fluid and plasma miRNAs have potential as diagnostic biomarkers for RA and OA and as a tool for the analysis of their pathogenesis.
Purpose
Medial release during total knee arthroplasty (TKA) is used to correct ligament imbalance in knees with varus deformity. However, questions remain on whether residual ligament imbalance would ...be related to inferior clinical results. The purposes of the present study were to measure the intraoperative joint gap and to evaluate the effect of intraoperative soft tissue condition on the new Knee Society Score (KSS 2011) at 2-year follow-up, without the maneuver of additional medial release to correct the asymmetrical gap balance.
Methods
Varus–valgus gap angle and joint gap were measured using a tensor device without medial release for 100 knees with preoperative varus deformity. The knees were categorized according to the varus–valgus gap angle and the laxity. The preoperative and postoperative clinical outcomes using KSS 2011 were compared between the groups.
Results
The average varus–valgus angles had a residual imbalance of 2.8° varus and 1.3° varus in extension and flexion, respectively. In comparison, according to varus–valgus joint gap angle and knee laxity in extension and flexion, no significant differences were found in postoperative range of motion and subscale of KSS 2011 among the groups.
Conclusion
Intraoperative asymmetrical joint gap and physiological laxity do not affect early clinical results after TKA.
Level of evidence
III.
Frailty is a geriatric syndrome characterized by anabolic-catabolic imbalance and multisystem dysregulation resulting in increased adverse health outcomes, and is closely related with dietary habits ...in the general population. Although chronic inflammatory diseases are thought to accelerate development of frailty, correlations between rheumatoid arthritis (RA), frailty and dietary habits have not been examined. We performed a cross-sectional study using our cohort database (KURAMA cohort), and classified 306 participants into three groups (robust, prefrail and frail) according to the Study of Osteoporotic Fracture (SOF) criteria. Multivariate logistic analysis revealed that the presence of frailty/prefrailty was significantly correlated with the disease activity score (DAS28-ESR) (OR 1.70 (1.30-2.22), p < 0.0001). Additional analyses of frailty and food intake showed that 5 foods (fish, meat, milk, vegetables and fruits) of 20 groups on the questionnaire were inversely associated with the prevalence of frail/prefrail categories. In multivariate analysis with the five nutrients, fish intake (> two times a week) was an independent covariate negatively correlated with frailty/prefrailty (OR 0.35 (0.19-0.63), p = 0.00060). In conclusion, habitual fish intake may play a key role in nutritional intervention to prevent progression of frailty and RA.
In human inflammatory sites, PD-1
CXCR5
CD4
T cells are involved in the formation of ectopic lymphoid-like structures (ELSs) by the secretion of chemokine CXCL13, but how the transcription of CXCL13 ...is regulated in CD4
T cells is still unclear. Here we show that Sox4 is a key transcription factor for CXCL13 production in human CD4
T cells under inflammatory conditions. In vitro TGF-β
, IL-2-neutralizing culture conditions give rise to PD-1
CXCR5
CD4
T cells that preferentially express CXCL13, and transcriptome analysis and lentiviral overexpression indicate Sox4 association with the CXCL13 transcription. In vivo, Sox4 is significantly upregulated in synovial CD4
T cells, when compared with blood CD4
T cells, from patients with rheumatoid arthritis (RA), and further correlates with ELS formation in RA synovium. Overall, our studies suggest that Sox4 contributes to CXCL13 production and ELS formation at inflammatory sites in humans.
Osteomyelitis is a devastating disease caused by microbial infection of bone. While the frequency of infection following elective orthopedic surgery is low, rates of reinfection are disturbingly ...high.
is responsible for the majority of chronic osteomyelitis cases and is often considered to be incurable due to bacterial persistence deep within bone. Unfortunately, there is no consensus on clinical classifications of osteomyelitis and the ensuing treatment algorithm. Given the high patient morbidity, mortality, and economic burden caused by osteomyelitis, it is important to elucidate mechanisms of bone infection to inform novel strategies for prevention and curative treatment. Recent discoveries in this field have identified three distinct reservoirs of bacterial biofilm including:
abscess communities in the local soft tissue and bone marrow, glycocalyx formation on implant hardware and necrotic tissue, and colonization of the osteocyte-lacuno canalicular network (OLCN) of cortical bone. In contrast,
intracellular persistence in bone cells has not been substantiated in vivo, which challenges this mode of chronic osteomyelitis. There have also been major advances in our understanding of the immune proteome against
, from clinical studies of serum antibodies and media enriched for newly synthesized antibodies (MENSA), which may provide new opportunities for osteomyelitis diagnosis, prognosis, and vaccine development. Finally, novel therapies such as antimicrobial implant coatings and antibiotic impregnated 3D-printed scaffolds represent promising strategies for preventing and managing this devastating disease. Here, we review these recent advances and highlight translational opportunities towards a cure.
Objective
This study aimed to determine whether alignment correction by high tibial osteotomy (HTO) can change the biologic intraarticular microenvironment of osteoarthritic (OA) knees.
Methods
...Synovial tissue (ST) and fluid (SF) were collected from the affected knees of 31 OA patients during initial HTO and plate removal surgeries. Changes in gene expression in ST were investigated by microarray and real‐time polymerase chain reaction (PCR). ST specimens were also evaluated histologically using synovitis scores and immunofluorescence staining to determine macrophage polarity. Cytokines and chemokines in SF were analyzed by enzyme‐linked immunosorbent assays. The mechanism of macrophage polarization was investigated in human peripheral blood mononuclear cell–derived macrophages and fibroblast‐like synoviocytes (FLS) stimulated with cartilage fragments. We also evaluated Spearman correlations between Knee Injury and Osteoarthritis Outcome scores (KOOS) and macrophage‐related gene expression.
Results
The microarray results indicated down‐regulated inflammatory genes and pathways. Real‐time PCR determined that genes expressing proinflammatory IL1B and IL6 were down‐regulated and M2 macrophage–related IL1RA, IL10, CCL18, and CD206 were up‐regulated. Histologic findings revealed attenuated synovitis scores and a shift from M1 to M2 macrophages. Interleukin‐1β (IL‐1β) concentrations in SF decreased after HTO. Cartilage fragments were responsible for M1 macrophage polarization and proinflammatory gene and protein expression in macrophages, whereas cartilage fragments up‐regulated only IL‐6 protein in FLS. Postoperative KOOS positively correlated with the expression of the M2‐related genes CCL18 and CD206.
Conclusion
Correction of lower limb alignment with HTO attenuated synovial inflammation and changed macrophage polarization from M1 to M2, suggesting an improved intraarticular environment in knee OA.
The new Knee Society Score (2011KSS) has been used to evaluate post-operative outcomes after total knee arthroplasty (TKA). However, there is no minimum clinically important difference (MCID) for ...2011KSS. The purpose of this study is to define MCID of 2011KSS after TKA.
Patients who underwent primary TKA for primary knee osteoarthritis between April 2012 and December 2016 were included in the study. The Japanese version of 2011KSS and original Knee Society Score (OKSS) were recorded preoperatively and at one-year postoperatively. With improvement in pain score of OKSS as an anchor, an anchor-based approach was used to identify the MCID of 2011KSS. The improvement in pain of OKSS was classified into 5 categories. The MCID was determined using a linear regression analysis of delta 2011KSS against improvement in the category of pain in OKSS. The MCID for 2011KSS expectation was not calculated because the items of pre- and post-operative questionnaires were different.
Five hundred and twenty-two cases were enrolled (age: 74.8 ± 7.3 years, female: 80.0%). After 1-year follow-up, 344 TKAs were finally included (age: 74.6 ± 7.1 years, female: 77.9%). Linear regression analyses showed that MCID for 2011KSS was 1.9 (95% confidential interval (CI): 1.3-2.5) in symptom, 2.2 (95%CI: 1.4-2.9) in satisfaction, and 4.1 (95%CI: 2.5-5.7) in functional activities.
MCID for 2011KSS was successfully calculated. These MCID values make the 2011KSS a more efficient tool for evaluating the physical activities of the populations of patients undergoing TKA. These MCID values can also be used to calculate sample size to evaluate the power of a study in designing clinical studies.