Twenty-year survivorship cohort study of total knee arthroplasty in Asian patient using a single posterior-stabilized implant performed by a single surgeon.

INTRODUCTION: As life expectancy has improved, the potential number of revision candidates is also expected to increase among patients who have undergone a total knee arthroplasty (TKA). The longevity of modern posterior stabilized knee prostheses after 20 years of use has not been well documented, especially in Asian populations that require a deeper flexion range due to a floor-based lifestyle. HYPOTHESIS: Firstly, the implant longevity regarding mechanical failures such as aseptic loosening and polyethylene (PE) wear would vary over a longer follow-up depending on the age groups; and secondly there would be unique risk factors for revision surgery in an Asian TKA cohort. MATERIAL AND METHODS: We conducted this age-stratified survival analysis in a consecutive series of 368 NexGen Legacy Posterior Stabilized (LPS) TKAs performed by a single surgeon. These cases were divided into four age groups (< 60 years, early 60s, late 60s, and ≥ 70 years). The implant longevity against aseptic mechanical failures was calculated using the Kaplan-Meier method. The revision surgery risk was evaluated using postoperative factors including a deep flexion capability (> 135̊), and postoperative mechanical alignments. RESULTS: Overall survivorship was significantly lower in the youngest groups than other groups (Log-rank test, p=0.001). The cumulative 20-year implant longevity was more than 95% in the two oldest groups, but less than 60% in the youngest group. It was notable that the post-TKA implant longevity was not apparent up to 10 years between the age groups (p=0.073∼0.458). Aseptic loosening was observed with an earlier onset (3.1 to 18.9 years) trend than PE wear (9.8∼17.9 years), with most cases arising in the youngest groups. Flexion limitation and varus alignment were significant risks to aseptic loosening and PE wear (Cox proportional hazard regression: p=0.001 and 0.045, respectively). DISCUSSION: A younger age (< 60 years), inability of postoperative deep flexion, and varus alignment were significant risk factors for aseptic loosening and PE wear after modern PS design in this Asian cohort. The difference in postoperative longevity affected by these factors was not obvious during the first 10 years but emerged over a second decade. LEVEL OF PROOF: III; retrospective cohort study.

Proposal of a New Prognostic Model for Differentiated Thyroid Cancer with TERT Promoter Mutations.

The role of telomerase reverse transcriptase (TERT) promoter mutations as an independent poor prognostic factor in differentiated thyroid cancer (DTC) patients is well known, but there is no prognostic system that combines the TERT promoter mutation status with tumor-node-metastasis (TNM) stage to predict cancer-specific survival (CSS). A total of 393 patients with pathologically confirmed DTC after thyroidectomy were enrolled. After incorporating wild-type TERT and mutant TERT with stages I, II, and III/IV of the AJCC TNM system 8th edition (TNM-8), we generated six combinations and calculated 10-year and 15-year CSS and adjusted hazard ratios (HRs) for cancer-related death using Cox regression. Then, a new mortality prediction model termed TNM-8T was derived based on the CSS and HR of each combination in the four groups. Of the 393 patients, there were 27 (6.9%) thyroid cancer-related deaths during a median follow-up of 14 years. Patients with a more advanced stage had a lower survival rate (10-year CSS for TNM-8T stage 1, 2, 3, and 4: 98.7%, 93.5%, 77.3%, and 63.0%, respectively; p < 0.001). TNM-8T showed a better spread of CSS (p < 0.001) than TNM-8 (p = 0.002) in the adjusted survival curves. The C-index for mortality risk predictability was 0.880 (95% CI, 0.665-0.957) in TNM-8T and 0.827 (95% CI, 0.622-0.930) in TNM-8 (p < 0.001). TNM-8T, a new prognostic system that incorporates the TERT mutational status into TNM-8, showed superior predictability to TNM-8 in the long-term survival of DTC patients.

Changes in Smoking, Alcohol Consumption, and the Risk of Thyroid Cancer: A Population-Based Korean Cohort Study.

To elucidate potential causality between smoking and alcohol intake on thyroid cancer incidence, we explored the effect of changes in smoking and alcohol consumption habits. From the Korean National Health Insurance database, we identified 4,430,070 individuals who participated in the national health screening program in 2009 and 2011. The level of smoking and alcohol consumption was measured twice, once in 2009 and again in 2011. The risk of thyroid cancer according to their changes was estimated using the Cox proportional hazard model. During the mean follow-up period of 6.32 ± 0.72 years, 29,447 individuals were diagnosed with thyroid cancer. Compared to those who sustained not smoking, non-smokers who initiated smoking to light (adjusted hazard ratio (aHR) 0.96, 95% confidence interval (CI) 0.81-1.15), moderate (aHR 0.90, 95% CI 0.78-1.04), and heavy level (aHR 0.81, 95% CI 0.69-0.96) had a decreased risk of thyroid cancer. Heavy smokers who quit smoking had an increased risk of thyroid cancer (aHR 1.23, 95% CI 1.06-1.42) compared to those who sustained heavy smoking. Change in drinking status was not significantly associated with thyroid cancer risk compared to drinking at the same level, although a non-significant trend of increased risk was noted in quitters. Participants who initiated both smoking and drinking (HR 0.80, 95% CI 0.69-0.93) had a lower risk of thyroid cancer compared with those who continued not to smoke and drink. Our findings provide further evidence that smoking, and possibly alcohol consumption, would have true protective effects on the development of thyroid cancer.

Comparison of Four Ultrasonography-Based Risk Stratification Systems in Thyroid Nodules with Nondiagnostic/Unsatisfactory Cytology: A Real-World Study.

We compared American Thyroid Association (ATA) guidelines, Korean (K)-Thyroid Imaging, Reporting and Data Systems (TIRADS), EU-TIRADS, and American College of Radiology (ACR) TIRADS in diagnosing malignancy for thyroid nodules with nondiagnostic/unsatisfactory cytology. Among 1143 nondiagnostic/unsatisfactory aspirations from April 2011 to March 2016, malignancy was detected in 39 of 89 excised nodules. The minimum malignancy rate was 7.82% in EU-TIRADS 5 and 1.87-3.00% in EU-TIRADS 3-4. In the other systems, the minimum malignancy rate was 14.29-16.19% in category 5 and ≤3% in the remaining categories. Although the EU-TIRADS category ≥ 5 exhibited the highest positive likelihood ratio (LR) of only 2.214, category ≥ 5 in the other systems yielded the highest positive LR of >5. Receiver operating characteristic (ROC) curves of all systems to predict malignancy were located statistically above the diagonal nondiscrimination line (P for ROC curve: EU-TIRADS, 0.0022; all others, 0.0001). The areas under the ROC curve (AUCs) were not significantly different among the four systems. The ATA guidelines, K-TIRADS, and ACR TIRADS may be useful to guide management for nondiagnostic/unsatisfactory nodules. The EU-TIRADS, although also useful, exhibited inferior performance in predicting malignancy for nondiagnostic/unsatisfactory nodules in Korea, an iodine-sufficient area.

Prognostic Value of the Neutrophil-to-Lymphocyte Ratio before and after Radiotherapy for Anaplastic Thyroid Carcinoma.

The neutrophil-lymphocyte ratio (NLR) is a marker of systemic inflammation, and its elevation has recently been associated with poor survival in many solid cancers. Leukocyte elevation and lymphocyte reduction are associated with a poor response to radiotherapy (RT). This study aimed to assess the prognostic value of NLR before and after RT for anaplastic thyroid carcinoma (ATC). This retrospective study analyzed 40 patients with ATC who received RT with available complete blood cell count data from November 1995 through May 2020 at Samsung Medical Center (Seoul, Korea). Patients were classified into two groups according to the NLR before and after RT. The median overall survival (OS) was 8.9 months (range, 3.5-18.2) in the low NLR group (<3.47) and 5.2 months (range, 2.7-7.5) months in the high NLR group (≥3.47). The association between NLR and OS was also observed in multivariable Cox regression analysis (hazard ratio, 3.18; 95% confidence interval, 1.15-8.85; p = 0.026). The OS curves differed significantly according to post-RT NLR (p = 0.036). A high NLR before and after RT may be significantly associated with poor OS in patients with ATC who receive RT.

Clinicoradiologic Outcomes of Medial Open-Wedge High-Tibial Osteotomy Are Equivalent in Bone-on-Bone and Non-Bone-on-Bone Medial Osteoarthritis.

PURPOSE: (1) To investigate whether patients with bone-on-bone (BOB) medial OA (Ahlback grade 2) had comparable clinical improvement to those with non-BOB arthritis with remaining joint space (Ahlback grades 0/1) after medial open-wedge high tibial osteotomy (MOWHTO); (2) to determine whether the radiological results differ between these 2 groups from 1 month postoperatively to last follow-up ≥2 years later. METHODS: Data of 132 knees (40 males and 92 females) who underwent MOWHTO were retrospectively reviewed. Preoperative standing anteroposterior radiographs were evaluated according to the Ahlback classification. Patients with Ahlback grade ≤1 were classified as the non-BOB group (group I, n = 88; mean age, 50.5 ± 6.3 years) and those with grade 2 as the bone-on-bone group (group II, n = 44; age, 51.6 ± 5.3 years). Clinical outcomes were assessed using Hospital for Special Surgery (HSS) and Knee Society (KS) functional scores. Medial joint space width (JSW), medial proximal tibial angle (MPTA), and mechanical alignment were considered radiological parameters. RESULTS: Preoperative clinical scores were significantly lower in patients with BOB arthritis (HSS score: group I, 73.5 ± 10.7 versus group II, 69.2 ± 9.1, P = .026; KS score: group I, 72.9 ± 10.3 versus group II, 63.2 ± 11.6 points, P < .001). However, HSS and KS functional scores improved in both groups without a significant difference at a mean follow-up of 3.4 ± 2.5 and 4.1 ± 3.1 years in groups I and II, respectively (HSS score: 89.2 ± 9.5 versus 89.4 ± 7.3 points, P = .258; KS functional score: 90.1 ± 7.1 versus 87.8 ± 8.9 points, P = .105). Preoperative and postoperative medial JSWs were narrower in group II, but the JSW opening was wider in group II at 1 month after surgery and was maintained until the last follow-up (preoperative, 3.0 ± 0.9 versus 0.0 ± 0.1 mm; 1 month, 3.1 ± 1.0 versus 1.4 ± 0.8; last follow-up, 3.0 ± 1.0 versus 1.4 ± 0.9 mm; P < .001). CONCLUSION: Patients with BOB medial OA achieved clinical outcomes comparable to those with remaining joint space after MOWHTO. The medial JSW showed a significant increase without OA progression during midterm follow-up in these patients. Therefore, MOWHTO can be an effective treatment choice for symptomatic improvement in middle-aged patients with severe medial OA, if there is no subchondral bone attrition. LEVEL OF EVIDENCE: III, retrospective comparative study.

Progression of radiographic osteoarthritis after partial meniscectomy in degenerative medial meniscal posterior root tears was greater in varus- than in neutral-aligned knees: a minimum 5-year follow-up.

PURPOSE: To perform a radiographic assessment of osteoarthritis, progression after partial meniscectomy (PM) in degenerative medial meniscus posterior root tears (MMPRTs) in relation to preoperative mechanical axis (MA). The hypothesis is that neutral-aligned knees with degenerative MMPRTs have better radiographic outcomes than those of varus-aligned knees after arthroscopic PM. METHODS: Records of 114 patients with degenerative MMPRTs and Kellgren-Lawrence (KL) grade ≤ 2 osteoarthritis, who underwent PM, had preoperative weight-bearing hip-to-ankle radiographs from 2004 to 2014, and were followed-up for at least 5 years were reviewed retrospectively. The mean follow-up period was 8.3 ± 2.8 years. Preoperative MA values were used to classify the patients into either a Neutral (N valgus 3° to varus 3°; n = 60) or Varus-aligned group (V varus > 3°; n = 54). Joint space width (JSW; mm) and KL grade (0/1/2/3/4) were measured preoperatively and finally on weight-bearing 45° flexion posteroanterior and anteroposterior radiographs, respectively. RESULTS: Preoperative JSW and KL grade did not differ significantly between the groups (N vs V; JSW 3.64 ± 0.83 vs 3.44 ± 0.81, P = 0.201; KL grade, 2/31/27/0/0 vs 0/22/32/0/0, P = 0.162); however, the final JSW and KL grade differed significantly between the groups (N vs V; JSW 3.03 ± 0.78 vs 2.07 ± 0.87; KL grade, 0/21/23/13/3 vs 0/10/26/21/6, both P < 0.001). The N group showed significantly less KL progression compared with the V group (N vs V; progression/no progression, 27/33 vs 42/12, P = 0.001). CONCLUSION: The progression of radiographic osteoarthritis after PM for degenerative MMPRTs was greater in varus-aligned knees than in neutral-aligned knees. PM should be considered cautiously in patients with varus-aligned knees. LEVEL OF EVIDENCE: Retrospective comparative study, Level III.

Suppressive effects of Schizandra chinensis Baillon water extract on allergy-related cytokine generation and degranulation in IgE-antigen complex-stimulated RBL-2H3 cells.

Schizandra chinensis Baillon is a traditional folk medicine plant that is used to treat and prevent several inflammatory diseases and cancer in Korea, but the underlying mechanisms involved in its anti-allergic activity are not fully understood. This study was designed to investigate mechanisms of anti-allergic activity of a Schizandra chinensis Baillon water extract (SCWE) in immunoglobulin E (IgE)-antigen complex-stimulated RBL2H3 cells and to assess whether gastric and intestinal digestion affects the anti-allergic properties of SCWE. Oxidative stress is an important consequence of the allergic inflammatory response. The antioxidant activities of SCWE increased in a concentration-dependent manner. RBL-2H3 cells were sensitized with monoclonal anti-dinitrophenol (DNP) specific IgE, treated with SCWE, and challenged with the antigen DNP-human serum albumin. SCWE inhibited ß-hexosaminidase release and expression of interleukin (IL)-4, IL-13, and tumor necrosis factor-alpha (TNF-α) mRNA and protein in IgE-antigen complex-stimulated RBL2H3 cells. We found that digested SCWE fully maintained its antioxidant activity and anti-allergic activity against the IgE-antigen complex-induced activation of RBL-2H3 cells. SCWE may be useful for preventing allergic diseases, such as asthma. Thus, SCWE could be used as a natural functional ingredient for allergic diseases in the food and/or pharmaceutical industries.

Design and synthesis of new bis-pyridinium oxime reactivators for acetylcholinesterase inhibited by organophosphorous nerve agents.

New bis-pyridinium oxime reactivators connected with a CH(2)CH(2)OCH(2)CH(2) linker between two pyridinium rings were designed and synthesized. In the test of their potency to reactivate AChE inhibited by cyclosarin, the bis-pyridinium oxime 6b achieved reactivation potency higher than 10% at the lower concentration 10(-4)M.

Comparison of monomeric and polymeric chiral stationary phases.

Two-type polymeric chiral stationary phases (pCSPs) were prepared by surface grafting of chiral acryl-type monomers on a silica gel surface modified with 3-(trimethoxysilyl)propylmethacrylate. The prepared pCSPs were characterized by IR, Fr-Raman, scanning electron microscopy, and elemental analysis. In addition, two-type monomeric chiral stationary phases (mCSPs) were also prepared. The racemic analytes were separated using the prepared mCSPs and pCSPs. The separation factor (alpha) and capacity factor (k1) of the racemic analytes for the pCSP and mCSP were compared. The alpha and k1 values of the mCSP were higher than those of the pCSP.