Background: Proximal humerus nails, frequently used for managing proximal humerus fractures, significantly enhance rotational stability and reinforce fractured fragments. Few research exists regarding the optimal number and positioning of distal screws.This study aimed to assess the stability of diverse screw configurations and scrutinize screw distribution and bone stress via finite element analysis. Methods: The humerus intramedullary nail (Humerus Interlocking Nail System; TDM) underwent assessment using finite element analysis applied to a humerus model. Three groups were established based on varying distal screw numbers and locations: all 3 distal locking holes were used in group 1; 2 screws (dynamic hole and proximal static hole) in group 2, and 2 screws (dynamic hole and distal static hole) in group 3. Finite element analysis computed stress distribution within the implant and bone for each group.A 1-mm fracture gap was simulated at the surgical neck, and stress distributions were analyzed in both normal and osteoporotic bone models. Results: Using two screws did not compromise rotational stability. Stress distribution analysis revealed stability across all groups without reaching failure strength. Group 3 exhibited a minor rise in component 11 (direct stress [force per unit area] acting on the positive and negative 1 faces in the 1-axis. direction) and component 22 (direct stress [force per unit area] acting on the positive and negative 2 faces in the 2-axis direction) stress, remaining below failure strength thresholds. Group 1 exhibited the lowest von Mises stress in the nail and screws, while groups 2 and 3 did not reach failure strength levels. Findings remained consistent in the osteoporotic model. Conclusions All 3 groups demonstrated rotational stability concerning stress distribution, indicating that using 2 screws for distal fixation does not adversely affect stability. This suggests the potential for saving surgical time and reducing radiation exposure without compromising stability.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.

Background/Aims: Infliximab treatment failure in patients with inflammatory bowel disease may result from sub-optimal infliximab trough level. An understanding of pharmacokinetics (PKs) is important to maintain an optimal trough level. PK studies of the switch to subcutaneous (SC) infliximab from intravenous (IV) infliximab using real-world data are lacking. We aimed to develop a population PK model of IV and SC infliximab to predict individual infliximab exposure during maintenance therapy. Methods: We used data from prospectively collected data on IV and SC infliximab concentrations in patients with inflammatory bowel disease receiving maintenance treatment from February 2020 to December 2022 at Samsung Medical Center. Population PK analysis was conducted by using a two-compartment model with first-order absorption and first-order elimination. Goodness-of-fit plots and visual predictive check were used to evaluate the PK model. Results: A total of 2,132 samples from 181 patients (149 Crohn’s disease and 32 ulcerative colitis) were analyzed. We developed an infliximab population PK model using body mass index, albumin, C-reactive protein level, and the anti-drug antibody level and validated its predictive performance. Conclusions It may be possible to predict the infliximab trough level of both IV and SC infliximab in patients with inflammatory bowel disease during maintenance treatment by using our model in real-world practice.

Purpose: The classification of asthma phenotypes frequently depends on the age of onset. However, the rationale for specific age cutoffs remains unclear. This study aimed to explore the distribution of asthma onset age, to define subgroups based on onset age, and to examine their characteristics within a broad Korean population. Methods: An analysis of cross-sectional data involving 56,632 participants from the Korean National Health and Nutrition Examination Survey (2010–2016) was conducted. Data on asthma history, including diagnosis, self-reported age of asthma onset, and current disease status, were collected using structured questionnaires. Results: The distribution of asthma onset age showed a distinct peak in early childhood, with a decline between the ages 15 and 20.Based on this distribution, asthma was categorized into childhood-onset ( ≤ 18 years) and adult-onset ( > 18 years) for further analysis.Multivariate analyses indicated that adult-onset asthma was associated with older age, female sex, obesity, and a history of smoking, whereas childhood-onset asthma was linked to younger age, male sex, allergic rhinitis, and atopic dermatitis. Among the adultonset group, current asthma had a later onset age, increased history of smoking history, and atopic dermatitis compared to past asthma. Conclusion This analysis of nationwide general population data suggests that an age threshold around 18 years may be relevant for defining adult-onset asthma.

Purpose: The technique for transanal resection of rectal tumors has evolved from conventional methods to minimally invasive approaches. However, the research comparing long-term results between these approaches is limited. Methods: Between 2016 and 2022, a total of 133 patients who underwent transanal excision were analyzed. Patients were classified into 2 groups according to surgical approach: conventional transanal approach (CTA) and minimally invasive transanal approach (MTA). Medical records were analyzed to compare surgical and oncological outcomes between the 2 groups. Results: There were no significant differences observed in patient’s demographics and tumor characteristics, except the MTA group exhibited a statistically longer distance from the anal verge. Although statistical significance was not reached, the MTA group demonstrated a 100% margin-negative rate in contrast to the CTA group, which had worse outcomes for both margin status and fragmentation. Recurrence was observed only in the CTA group containing pT1 rectal cancer and grade 1 neuroendocrine tumor, with negative margins and no fragmentation. Conclusion The minimally invasive approach did not demonstrate statistical superiority but showed technical feasibility through the absence of margin-positive cases and the use of the clip handle method. Further studies are needed to validate these findings and assess broader applicability.

Purpose: The long-term outcomes and efficacy of partial stapled hemorrhoidopexy (PSH) compared with those of conventional hemorrhoidectomy (CH) are not fully understood. This study aimed to introduce a modified PSH (mPSH) and compare its clinical efficacy and safety with those of CH. Methods: A prospective randomized controlled trial was conducted. This study was performed at a single hospital and involved 6 colorectal surgeons. In total, 110 patients were enrolled between July 2019 and September 2020. Patients were randomly assigned to undergo either mPSH group (n=55) or CH group (n=55). The primary outcome was to compare postoperative average pain and postoperative peak pain using visual analog scale score between the 2 groups. Results: The required duration of analgesia was shorter in the mPSH group than in the CH group, although the difference was not statistically significant (P=0.096). However, the laxative requirement duration (P<0.010), return to work (P<0.010), satisfaction score (P<0.010), and Vaizey score (P=0.014) were significantly better in the mPSH group. The average and peak postoperative pain scores were significantly lower in the mPSH group during the 15 days after surgery (P<0.001). The overall complication rate in both groups was 9.1%, with no significant difference between the groups (P=0.867). Conclusion The mPSH group demonstrated better improvement in symptoms, lower pain scores, and greater patient early satisfaction after surgery than the CH group. Therefore, this surgical technique appears to be a safe and effective alternative for CH.

Background: s/Aims: While large-for-size syndrome is uncommon in liver transplantation (LT), it can result in fatal outcome. To prevent such fatality, we manufactured 3D-printed intra-abdominal cavity replicas to provide intuitive understanding of the sizes of the graft and the patient’s abdomen in patients with small body size between July 2020 and February 2022. Methods: Clinical outcomes were compared between patients using our 3D model during LT, and patients who underwent LT without 3D model by using 1 : 5 ratio propensity score-matched analysis. Results: After matching, a total of 20 patients using 3D-printed abdominal cavity model and 100 patients of the control group were included in this study. There were no significant differences in 30-day postoperative complication (50.0% vs. 64.0%, p = 0.356) and the incidence of large-for-size syndrome (0% vs. 7%, p = 0.599). Overall survival of the 3D-printed group was similar to that of the control group (p = 0.665), but graft survival was significantly superior in the 3D-printed group, compared to the control group (p = 0.034). Conclusions Since it showed better graft survival, as well as low cost and short production time, our 3D-printing protocol can be a feasible option for patients with small abdominal cavity to prevent large-for-size syndrome after LT.

Purpose: Treatment options for hepatocellular carcinoma (HCC) vary according to known guidelines among liver resection (LR), liver transplantation (LT), radiofrequency ablation (RFA), and transarterial chemoembolization (TACE). This study aimed to compare the outcomes of initial treatment for patients with resectable HCC within Milan criteria (MC) via nationwide data. Methods: Patients with resectable HCC (Child-Pugh class A; platelet count, ≥100,000/μL) within MC from the Korean Liver Cancer Association databank were analyzed, retrospectively. Outcomes according to initial treatment and subgroups according to tumor size and number were analyzed. Overall survival (OS) rates after initial treatment were compared. Results: A total of 3,241 patients who underwent LR (n = 1,371), LT (n = 12), RFA (n = 679), or TACE (n = 1,179) were included. The 5-year OS rates differed significantly between the groups (P < 0.05), except for LT (LR, 84.9%; LT, 82.5%;RFA, 76.2%; and TACE, 59.9%). For patients with a single tumor of any size, the 5-year OS rates of the LR group were significantly higher than RFA and TACE groups. For patients with multiple tumors, the 5-year OS rates were 78.2%, 100%, 74.3%, and 53.0% for the LR, LT, RFA, and TACE groups, respectively, but without significant difference between LR and RFA (P = 0.86). Conclusion For resectable HCC within MC, the LR had the highest OS rate for a single tumor of any size. LR and RFA showed no significant differences in OS rate for multiple tumors. LR has a much more optimistic outlook for HCC within MC.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

Objective: This study aimed to quantitatively assess abnormalities in the talar dome cartilage using MRI T2 mapping, with additional analyses based on the Lauge-Hansen (LH) classification and anatomical locations. Materials and Methods: This retrospective study analyzed 78 patients who underwent ankle MRI with T2 mapping for acute ankle trauma between January 2021 and October 2022. Patients were classified into the supination (S) and pronation (P) groups based on the LH classification, and then divided into subgroups based on posterior malleolus (PM) involvement. The T2 values for the talar cartilage were quantitatively measured in six anatomical regions defined by the combination of medial vs.lateral and anterior vs. central vs. posterior. The T2 mapping values in each region of the talus were compared between the S and P groups and between the PM and non-PM injury groups using t-tests. The T2 values were also compared between the medial and lateral sides within each group. Results: Among the 78 patients (mean age, 38.62 ± 14.82 years; 47 male), 53 and 25 were in the S and P groups, respectively, and 53 patients showed PM involvement. In comparison with the P group, the S group exhibited higher T2 values in the medial portion (61.27 ± 8.30 vs. 54.03 ± 6.96; P < 0.001) and lower T2 values in the lateral talus (54.95 ± 8.47 vs. 64.15 ± 7.31; P < 0.001). The PM injury group showed higher T2 values in the posterior region than the non-PM injury group (P ≤ 0.011). Within the PM injury group, T2 values were higher in the anteromedial and posterolateral regions than on the opposite sides (P= 0.037 and 0.011, respectively). Conclusion MRI T2 values demonstrated significant regional variations in the talar dome cartilage in acute ankle trauma, and the T2 values may reflect different ankle trauma mechanisms and PM involvement. Thus, T2 mapping can facilitate evaluation of talar cartilage alterations.