1.Sarcopenia: From Global Consensus to Korean Implementation — A Narrative Review and Standpoint
Geon Young JANG ; Sunghwan JI ; Heewon JUNG ; Ji Yeon BAEK ; Il-Young JANG ; Kyoung Min KIM ; Miji KIM ; Clara Yongjoo PARK ; Kwang-Pyo LEE ; Dongryeol RYU ; Sang Yoon LEE ; Ok Hee JEON ; Sunyoung KIM ;
Annals of Geriatric Medicine and Research 2026;30(1):3-17
Sarcopenia is a major geriatric syndrome characterized by progressive loss of muscle mass and strength, resulting in disability and mortality. This narrative review synthesizes international consensus recommendations and Korean evidence to guide context-specific sarcopenia management strategies. PubMed, Embase, Cochrane Library, and KoreaMed (January 2000–November 2025) were searched, focusing on randomized trials, meta-analyses, systematic reviews, clinical practice guidelines, and large observational studies. Global diagnostic frameworks have evolved from muscle mass-based definitions toward multidimensional models that incorporate muscle strength and physical performance. Exercise and nutrition remain the mainstay treatments, with resistance-based training and adequate protein intake. Currently, pharmacologic options with proven clinical benefit are limited. In Korea, growing evidence supports the effectiveness of community-based sarcopenia interventions, underscoring the need for standardized, integrated delivery models that bridge the fragmented healthcare system and enable sustainable implementation.
2.Nerve Root Herniation Due to Delayed Dural Tear Following Unilateral Laminotomy for Bilateral Decompression With Lumbar Discectomy Using Unilateral Biportal Endoscopy
Sang Hyub LEE ; Jae-Won JANG ; Yong Eun CHO ; Choon Keun PARK
Journal of Minimally Invasive Spine Surgery and Technique 2026;11(Suppl 1):S109-S115
This case report describes a delayed dural tear with subsequent nerve root herniation following unilateral laminotomy for bilateral decompression (ULBD) combined with lumbar discectomy using unilateral biportal endoscopy (UBE). A 31-year-old woman underwent UBE ULBD with lumbar discectomy via a left-sided approach for extremely severe L4–5 central canal stenosis with a central disc herniation. No dural tear occurred intraoperatively; however, the dorsal dura was extremely thinned and translucent, with the nerve roots faintly visible through the thecal sac. Following the initial operation, the patient’s symptoms improved, and she was discharged without complications. One week later, the patient developed recurrent severe radiating pain in the left leg. Follow-up magnetic resonance imaging (MRI) revealed cerebrospinal fluid (CSF) leakage and findings suspicious for nerve root herniation. Revision surgery was performed to reduce the herniated nerve root and repair the dural tear. After revision surgery, the patient’s symptoms improved, and postoperative MRI obtained 1 week later showed no evidence of CSF leakage. During 6 months of follow-up, no further complications were observed. Delayed dural tear with nerve root herniation is rare but clinically significant, and revision surgery is often unavoidable. Prophylactic reinforcement may be advisable when translucent, thinned dura is encountered.
3.Unilateral Biportal Endoscopic Transforaminal Lumbar Interbody Fusion (TLIF) Using 3-Dimensional-Printed Titanium Cages Compared With Open TLIF: A Comparison of Clinical Outcomes and Fusion Rates
Sang Hyub LEE ; Junghan SEO ; Dain JEONG ; Sang Youp HAN ; Dong Hyun LEE ; Jae-Won JANG ; Dong-Geun LEE ; Choon Keun PARK
Journal of Minimally Invasive Spine Surgery and Technique 2026;11(Suppl 1):S28-S40
Objective:
Unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) has emerged as an alternative to open TLIF. However, limited evidence is available regarding the application of 3-dimensional (3D)-printed titanium cages in UBE-TLIF. We aimed to compare the clinical outcomes and fusion rates of UBE-TLIF and open TLIF using 3D-printed titanium cages.
Methods:
We retrospectively reviewed patients who underwent single-level TLIF with 3D-printed titanium cages between 2021 and 2023. The inclusion criterion was degenerative lumbar stenosis, while the exclusion criteria were trauma, infection, and multilevel surgery. Clinical and radiologic outcomes were compared between the UBE-TLIF and open TLIF groups.
Results:
Twenty-one patients underwent UBE-TLIF, and 21 underwent open TLIF. The visual analogue scale (VAS) for back (p=0.987) and leg pain (p=0.731) did not significantly differ between the groups at 1-year follow-up. However, VAS back pain at postoperative day 2 was significantly lower in the UBE-TLIF group than in the open TLIF group (p<0.001). Solid fusion was achieved in 21 patients (100%) in the open TLIF group and in 20 (95.2%) in the UBE-TLIF group (p=1.000). In multivariable logistic regression analysis, body mass index was the only factor that exhibited a significant relationship (odds ratio [OR], 0.70; 95% confidence interval [CI], 0.53–0.92; p=0.011) with interbody fusion. In contrast, the surgical method (UBE vs. open TLIF) was not a significant factor (OR, 0.47; 95% CI, 0.10–2.21; p=0.337).
Conclusion
Using a 3D-printed titanium cage for UBE-TLIF may yield comparable fusion rates to those of open TLIF.
4.Impact of COVID-19 on the Profitability of General Hospitals in Korea
Jun Young PARK ; Tae Hyun KIM ; Suk-Yong JANG ; Sang Gyu LEE
Journal of Preventive Medicine and Public Health 2026;59(1):46-55
Objectives:
This study was performed to quantify the impact of coronavirus disease 2019 (COVID-19) on hospital profitability in Korea by analyzing changes in the medical revenue-to-profit ratio (MRPR) and net income before reserve fund allocation (NIBR) before and after the pandemic onset. Additionally, it examined how financial outcomes varied by hospital ownership, geographic location, and type (secondary or tertiary), providing insights into the financial resilience of various hospital types during public health crises.
Methods:
We conducted a longitudinal analysis using publicly available financial disclosure data from 243 general hospitals in Korea (2016–2022). We then performed a quadrant analysis to classify hospitals based on changes in MRPR and NIBR, identifying patterns of financial impact. For inferential analysis, we employed linear mixed-effects models incorporating a difference-in-differences framework, enabling estimation of both time-varying and hospital-specific effects.
Results:
Following the onset of COVID-19, MRPR declined significantly, reaching −10.62% in 2020. NIBR initially dropped but later increased, reaching 21.09 billion Korean won per 100 beds in 2022. Quadrant analysis revealed substantial heterogeneity in financial responses, with national/public hospitals experiencing the most severe MRPR decline, whereas educational foundation and medical corporation hospitals displayed stronger financial recovery. Regression results confirmed significant interactions between outcomes after COVID-19 onset and hospital ownership type, indicating differential financial impacts across hospital categories.
Conclusions
The findings highlight the uneven financial effects of COVID-19 on Korean hospitals, emphasizing the importance of targeted government financial support. Policy measures should prioritize structural financial reforms to ensure hospital sustainability beyond short-term crisis management.
5.Individualized strategy of treatment for ruptured abdominal aortic aneurysm using causal inference model: a retrospective observational study
Youngki SOHN ; Youngje WOO ; Sangkyun MOK ; Eunju JANG ; Ki-Yoon MOON ; Sun Cheol PARK ; Sang Seob YUN ; Jang Yong KIM
Annals of Surgical Treatment and Research 2026;110(4):259-272
Purpose:
This study was performed to predict individualized treatment strategies in ruptured abdominal aortic aneurysm (rAAA) by estimating the survival benefit of endovascular aneurysm repair (EVAR) and open surgical repair (OSR) based on anatomical and physiological features using a causal inference model.
Methods:
This retrospective study included 45 patients with de novo rAAA who underwent EVAR or OSR between 2012 and 2024. Thirty-three variables were analyzed. The model estimated individualized treatment effects (ITE) for 30-day survival.Model interpretability was assessed using Shapley Additive Explanations (SHAP) analysis. Five-fold cross-validation, receiver operating characteristic (ROC) analysis, and calibration plots were used for model evaluation. A clinical decision tree was developed to derive simplified decision rules.
Results:
The mean ITE was 0.22 ± 0.42, with 33% of patients classified as OSR-benefit candidates. SHAP analysis revealed that suprarenal angle, infrarenal angle, iliac anatomy, and proximal neck characteristics strongly influenced treatment effects. However, some predictors, such as low hemoglobin and systolic blood pressure favoring OSR, conflicted with clinical intuition. ROC analysis showed an area under the curve of 1.00, but calibration suggested overfitting due to a small sample size. Treatment-matched patients had a higher 30-day mortality rate than mismatched patients, suggesting potential bias or unmeasured confounding. The decision tree identified clinically relevant features but displayed structural inconsistencies and impractical cutoff values due to the limited sample size.
Conclusion
The X-learner model demonstrated the feasibility of individualized treatment prediction in rAAA but suffered from overfitting and limited generalizability. Validation with larger multicenter cohorts is necessary to confirm clinical applicability.
6.Detection Ability of Quality of Life Changes and Responsiveness of the KOQUSS-40 and the EORTC QLQ-C30/STO22 in Patients Who Underwent Gastrectomy: A Prospective Comparative Study
Bang Wool EOM ; Keun Won RYU ; Ji Yeong AN ; Yun-Suhk SUH ; In CHO ; Sung Geun KIM ; Ji-Ho PARK ; Hoon HUR ; Hyung-Ho KIM ; Sang-Hoon AHN ; Sun-Hwi HWANG ; Hong Man YOON ; Ki Bum PARK ; Hyoung-Il KIM ; In-Gyu KWON ; Han-Kwang YANG ; Byoung-Jo SUH ; Sang-Ho JEONG ; Tae-Han KIM ; Oh Kyoung KWON ; Hye-Seong AHN ; Ji Yeon PARK ; Ki Young YOON ; Myoung Won SON ; Seong-Ho KONG ; Young-Gil SON ; Geum Jong SONG ; Jong Hyuk YUN ; Jung-Min BAE ; Do Joong PARK ; Sol LEE ; Jun-Young YANG ; Kyung Won SEO ; You-Jin JANG ; So Hyun KANG ; Joongyub LEE ; Hyuk-Joon LEE ;
Cancer Research and Treatment 2026;58(1):221-231
Purpose:
The aim of this study is to compare the detection ability of quality of life (QoL) changes and responsiveness of the KOrean QUality of life in Stomach cancer patients Study group (KOQUSS)-40 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ).
Materials and Methods:
A multicenter prospective observational study was conducted to evaluate QoL changes after various gastrectomies between January 2021 and April 2022. Participants were instructed to complete the KOQUSS-40 and EORTC QLQ-C30/STO22 preoperatively and at 1, 3, 6, and 12 months postoperatively. QoL changes over time and QoL responsiveness were assessed for each questionnaire.
Results:
Data from 491 patients who underwent curative gastrectomy for gastric cancer at 22 institutions were analyzed. The summary scores of the KOQUSS-40 and EORTC QLQ-STO22 showed significant differences between the total and proximal gastrectomy groups (p=0.044 and p=0.038, respectively), but no difference was observed for the EORTC QLQ-C30. Dysphagia on the KOQUSS-40 was significantly different between the total and proximal gastrectomy groups (p=0.031); however, dysphagia on the EORTC QLQ-STO22 did not differ. The responsiveness of the KOQUSS-40 was similar to that of the EORTC QLQ in patients who experienced ≥ 10% body weight loss, but approximately 10% less in patients receiving adjuvant chemotherapy than the EORTC QLQ.
Conclusion
KOQUSS-40 has several advantages over EORTC QLQ-C30/STO22 when comparing QoL between the total and proximal gastrectomy groups. The findings provide information for researchers investigating the QoL of patients who have undergone curative gastrectomy for gastric cancer.
7.Reconstructing Bilateral Ischial Sores with a Single Hamstring Flap versus Dual Plane Flaps: A Case Report
Jang Hyun LEE ; Sang Hyun PARK ; Jungwoo CHANG
Journal of Wound Management and Research 2026;22(1):28-32
The reconstruction of bilateral ischial pressure sores presents a formidable challenge in reconstructive plastic surgery. Adequate padding over the ischial tuberosity and proper resurfacing of the defect are critical in preventing recurrence after reconstruction. We present a case of bilateral ischial sores reconstructed using two different approaches. A 62-year-old paraplegic man with bilateral ischial sores and osteomyelitis of both ischial tuberosities presented to the plastic surgery department. After serial debridement, the 6×4 cm ischial sore on the left side was reconstructed using dual-plane flaps—two independent flaps consisting of a biceps femoris muscle flap and a perforator-based fasciocutaneous island flap. The 7×4 cm ischial sore on the right side was reconstructed using a single hamstring flap, a composite flap consisting of a semitendinosus muscle flap with a distally linked skin flap. Both defects were successfully reconstructed, and the patient regained wheelchair ambulation. Both approaches—the dual-plane flaps and the single hamstring flap—are effective options for ischial sore reconstruction, as they provide sufficient volume and adequate resurfacing. Given the hamstring flap’s capacity to significantly reduce operative duration, it may be considered the primary surgical option. However, in the absence of a reliable perforator between the hamstring muscle and the overlying skin, dual-plane flaps should be selected.
8.Associated factors of osteoporosis and the impact of osteoporosis on all-cause mortality in incident hemodialysis older patients
Seunghye LEE ; Yoomee KANG ; Yu Ah HONG ; Sung Joon SHIN ; Soon Hyo KWON ; Sungjin CHUNG ; Young Youl HYUN ; Sang Heon SONG ; Jae Won YANG ; Won Min HWANG ; Jang-Hee CHO ; Kyung Don YOO ; In O SUN ; Gang-Jee KO ; Byung Chul YU ; Hyunsuk KIM ; Woo Yeong PARK ; Tae Won LEE ; Dong Jun PARK ; Eunjin BAE ;
Kidney Research and Clinical Practice 2026;45(1):110-119
Background:
With the aging population and advancements in medical care worldwide, the number of older patients with end-stage kidney disease continues to rise. This study aimed to identify factors associated with osteoporosis and osteopenia in older patients undergoing incident hemodialysis and assess their impact on mortality.
Methods:
We analyzed a large multicenter retrospective cohort of patients aged ≥70 years undergoing incident hemodialysis to identify factors associated with osteoporosis using logistic regression analysis and to assess the association of death with osteoporosis and osteopenia using Cox multivariable analysis.
Results:
Among 710 patients, 39.0% and 19.6% had osteoporosis and osteopenia, respectively. Osteoporosis was significantly associated with female sex, a history of fractures, and the absence of phosphate binder use. During a median follow-up of 36.8 months, 348 participants (58.8%) died. Mortality rates were the highest in the osteoporosis group (79.8%), followed by the osteopenia (77.2%) and normal bone mineral density (BMD) groups (35.2%). Cox regression analysis revealed that even after adjusting for covariates, the osteoporosis group was significantly associated with a higher mortality risk than the normal BMD group. Osteoporosis at the start of hemodialysis was significantly associated with higher mortality.
Conclusion
We should consider the importance of bone health in patients undergoing incident hemodialysis and pay attention to the use of phosphate binders and fracture prevention.
9.Impact of obesity on renal function in elderly Korean adults: a national population-based cohort study
Jihyun YANG ; Hui Seung LEE ; Chi-Yeon LIM ; Hyunsuk KIM ; Sungjin CHUNG ; Soon Hyo KWON ; Jang-Hee CHO ; Kyung Don YOO ; Woo Yeong PARK ; In O SUN ; Byung Chul YU ; Gang-Jee KO ; Jae Won YANG ; Won Min HWANG ; Sang Heon SONG ; Sung Joon SHIN ; Yu Ah HONG ; Eunjin BAE ; Young Youl HYUN
Kidney Research and Clinical Practice 2026;45(1):65-76
Background:
Obesity is a well-known risk factor for chronic kidney disease and its progression. However, the impact of obesity on the renal function of the elderly population is uncertain. We investigated the association between obesity and renal outcomes in the elderly.
Methods:
We analyzed 130,504 participants from the Korean National Health Insurance Service-Senior cohort. Obesity was classified according to body mass index (BMI), sex-specific waist circumference (WC), and the presence of metabolic syndrome. The primary outcome was renal function decline, defined as a decline in the estimated glomerular filtration rate (eGFR) of at least 50% from baseline or new-onset end-stage renal disease.
Results:
During a follow-up period of 559,531.1 person-years (median, 4.3 years), 2,486 participants (19.0%; incidence rate of 4.44 per 1,000 person-years) showed renal function decline. A multivariate Cox proportional hazards model revealed that BMI/WC was not associated with renal function decline. However, the group with metabolic syndrome had a significantly increased risk of renal function decline compared to the group without metabolic syndrome (adjusted hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13–1.36). Compared with the non-metabolic syndrome group, the adjusted HRs (95% CI) for participants with one through five components were 0.96 (0.84–1.11), 1.10 (0.96–1.27), 1.24 (1.06–1.45), 1.37 (1.12–1.66), and 1.99 (1.42–2.79), respectively (p for trend < 0.001).
Conclusion
In elderly Korean adults, metabolic syndrome and the number of its components were associated with a higher risk of renal function decline, but BMI or WC was not significant.
10.An adjustment of fraction of inspired oxygen using the oxygen reserve index during one-lung ventilation in pediatric patients: a prospective, randomized controlled trial
Jung-Bin PARK ; Pyoyoon KANG ; Sang-Hwan JI ; Young-Eun JANG ; Eun-Hee KIM ; Jin-Tae KIM ; Hee-Soo KIM ; Ji-Hyun LEE
Korean Journal of Anesthesiology 2026;79(2):224-232
Background:
One-lung ventilation (OLV) during thoracic surgery frequently requires approximately 100% oxygen, imposing the risk of hyperoxemia. This study aimed to assess whether oxygen reserve index (ORI)-guided fraction of inspired oxygen (FiO2) adjustment can reduce the incidence of hyperoxemia in children undergoing lung resection.
Methods:
This prospective, randomized controlled trial enrolled children aged < 7 years scheduled for thoracoscopic lung resection. The participants were randomly assigned to either a conventional group (FiO2 adjusted based on arterial blood gas analysis [ABGA]) or an ORI group (FiO2 titrated to maintain an ORI target of 0.15). ABGA was performed 10 and 30 min after the start of OLV (T1 and T2). The primary outcome was the incidence of hyperoxemia 30 min after OLV (T2).
Results:
Data from 64 children (31 conventional, 33 ORI groups) were analyzed. The incidence rate of hyperoxemia at T2 was similar between the conventional and ORI groups (54.8% vs. 60.6%, P = 0.801). However, partial pressure of arterial oxygen at T1 was significantly lower in the ORI group than in the conventional group (214.6 ± 65.5 mmHg vs. 268.8 ± 92.7 mmHg, P = 0.014). The ORI group demonstrated a lower time-weighted average FiO2 during OLV (0.79 ± 0.12 vs. 0.87 ± 0.09, P = 0.004). The ORI group required more rescue interventions than the conventional group and experienced fewer episodes of hypoxia.
Conclusions
ORI-guided FiO2 adjustment does not significantly reduce the incidence of hyperoxemia in children undergoing OLV but reduces time-weighted FiO2 and hypoxic events.

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