1.Influence of Patellar Implant Shape on Patellofemoral Contact Pressure Using Finite Element Analysis
Hun Sik CHO ; Hyoung-Taek HONG ; Hyuck Min KWON ; Yong-Gon KOH ; Seong-Mun HWANG ; Kwan Kyu PARK ; Kyoung-Tak KANG
Yonsei Medical Journal 2025;66(6):383-389
Purpose:
This study focused on analyzing the contact pressure and area on different patellar component designs in total knee arthroplasty (TKA) to evaluate biomechanics related to the patellofemoral (PF) joint.
Materials and Methods:
The patellar components studied included the dome design, modified dome design, and anatomical design implants. Using finite element analysis and mechanical testing, the pressure and area were evaluated. The first loading condition was simulated at flexion angles of 0°, 15°, 45°, 90°, 120°, and 150°. The second loading condition was simulated for a clinically relevant scenario, involving a 2-mm medial shift at a flexion angle of 45°.
Results:
For both the modified dome and anatomical designs, the contact area and pressure increased with the flexion angle. The dome design reached its maximum contact area at a flexion angle of 120°. Among the designs, the anatomical design had the largest contact area and a lower contact pressure compared to the dome and modified dome designs. However, when a medial shift of 2 mm was simulated at a 45° flexion angle, which can occur clinically, the anatomical design showed edge contact, leading to higher contact pressure and reduced contact area. In contrast, the modified dome design demonstrated the lowest contact pressure and the greatest contact area under the same shifted conditions.
Conclusion
These findings suggest that the design of the patellar component significantly affects patellar biomechanics and stability. Specifically, the modified dome design showed improved biomechanical effects in clinically relevant scenarios. Therefore, patellar components with a modified dome design are expected to better manage PF joint pain and reduce complications in TKA.
2.Influence of Patellar Implant Shape on Patellofemoral Contact Pressure Using Finite Element Analysis
Hun Sik CHO ; Hyoung-Taek HONG ; Hyuck Min KWON ; Yong-Gon KOH ; Seong-Mun HWANG ; Kwan Kyu PARK ; Kyoung-Tak KANG
Yonsei Medical Journal 2025;66(6):383-389
Purpose:
This study focused on analyzing the contact pressure and area on different patellar component designs in total knee arthroplasty (TKA) to evaluate biomechanics related to the patellofemoral (PF) joint.
Materials and Methods:
The patellar components studied included the dome design, modified dome design, and anatomical design implants. Using finite element analysis and mechanical testing, the pressure and area were evaluated. The first loading condition was simulated at flexion angles of 0°, 15°, 45°, 90°, 120°, and 150°. The second loading condition was simulated for a clinically relevant scenario, involving a 2-mm medial shift at a flexion angle of 45°.
Results:
For both the modified dome and anatomical designs, the contact area and pressure increased with the flexion angle. The dome design reached its maximum contact area at a flexion angle of 120°. Among the designs, the anatomical design had the largest contact area and a lower contact pressure compared to the dome and modified dome designs. However, when a medial shift of 2 mm was simulated at a 45° flexion angle, which can occur clinically, the anatomical design showed edge contact, leading to higher contact pressure and reduced contact area. In contrast, the modified dome design demonstrated the lowest contact pressure and the greatest contact area under the same shifted conditions.
Conclusion
These findings suggest that the design of the patellar component significantly affects patellar biomechanics and stability. Specifically, the modified dome design showed improved biomechanical effects in clinically relevant scenarios. Therefore, patellar components with a modified dome design are expected to better manage PF joint pain and reduce complications in TKA.
3.Influence of Patellar Implant Shape on Patellofemoral Contact Pressure Using Finite Element Analysis
Hun Sik CHO ; Hyoung-Taek HONG ; Hyuck Min KWON ; Yong-Gon KOH ; Seong-Mun HWANG ; Kwan Kyu PARK ; Kyoung-Tak KANG
Yonsei Medical Journal 2025;66(6):383-389
Purpose:
This study focused on analyzing the contact pressure and area on different patellar component designs in total knee arthroplasty (TKA) to evaluate biomechanics related to the patellofemoral (PF) joint.
Materials and Methods:
The patellar components studied included the dome design, modified dome design, and anatomical design implants. Using finite element analysis and mechanical testing, the pressure and area were evaluated. The first loading condition was simulated at flexion angles of 0°, 15°, 45°, 90°, 120°, and 150°. The second loading condition was simulated for a clinically relevant scenario, involving a 2-mm medial shift at a flexion angle of 45°.
Results:
For both the modified dome and anatomical designs, the contact area and pressure increased with the flexion angle. The dome design reached its maximum contact area at a flexion angle of 120°. Among the designs, the anatomical design had the largest contact area and a lower contact pressure compared to the dome and modified dome designs. However, when a medial shift of 2 mm was simulated at a 45° flexion angle, which can occur clinically, the anatomical design showed edge contact, leading to higher contact pressure and reduced contact area. In contrast, the modified dome design demonstrated the lowest contact pressure and the greatest contact area under the same shifted conditions.
Conclusion
These findings suggest that the design of the patellar component significantly affects patellar biomechanics and stability. Specifically, the modified dome design showed improved biomechanical effects in clinically relevant scenarios. Therefore, patellar components with a modified dome design are expected to better manage PF joint pain and reduce complications in TKA.
4.Influence of Patellar Implant Shape on Patellofemoral Contact Pressure Using Finite Element Analysis
Hun Sik CHO ; Hyoung-Taek HONG ; Hyuck Min KWON ; Yong-Gon KOH ; Seong-Mun HWANG ; Kwan Kyu PARK ; Kyoung-Tak KANG
Yonsei Medical Journal 2025;66(6):383-389
Purpose:
This study focused on analyzing the contact pressure and area on different patellar component designs in total knee arthroplasty (TKA) to evaluate biomechanics related to the patellofemoral (PF) joint.
Materials and Methods:
The patellar components studied included the dome design, modified dome design, and anatomical design implants. Using finite element analysis and mechanical testing, the pressure and area were evaluated. The first loading condition was simulated at flexion angles of 0°, 15°, 45°, 90°, 120°, and 150°. The second loading condition was simulated for a clinically relevant scenario, involving a 2-mm medial shift at a flexion angle of 45°.
Results:
For both the modified dome and anatomical designs, the contact area and pressure increased with the flexion angle. The dome design reached its maximum contact area at a flexion angle of 120°. Among the designs, the anatomical design had the largest contact area and a lower contact pressure compared to the dome and modified dome designs. However, when a medial shift of 2 mm was simulated at a 45° flexion angle, which can occur clinically, the anatomical design showed edge contact, leading to higher contact pressure and reduced contact area. In contrast, the modified dome design demonstrated the lowest contact pressure and the greatest contact area under the same shifted conditions.
Conclusion
These findings suggest that the design of the patellar component significantly affects patellar biomechanics and stability. Specifically, the modified dome design showed improved biomechanical effects in clinically relevant scenarios. Therefore, patellar components with a modified dome design are expected to better manage PF joint pain and reduce complications in TKA.
5.Influence of Patellar Implant Shape on Patellofemoral Contact Pressure Using Finite Element Analysis
Hun Sik CHO ; Hyoung-Taek HONG ; Hyuck Min KWON ; Yong-Gon KOH ; Seong-Mun HWANG ; Kwan Kyu PARK ; Kyoung-Tak KANG
Yonsei Medical Journal 2025;66(6):383-389
Purpose:
This study focused on analyzing the contact pressure and area on different patellar component designs in total knee arthroplasty (TKA) to evaluate biomechanics related to the patellofemoral (PF) joint.
Materials and Methods:
The patellar components studied included the dome design, modified dome design, and anatomical design implants. Using finite element analysis and mechanical testing, the pressure and area were evaluated. The first loading condition was simulated at flexion angles of 0°, 15°, 45°, 90°, 120°, and 150°. The second loading condition was simulated for a clinically relevant scenario, involving a 2-mm medial shift at a flexion angle of 45°.
Results:
For both the modified dome and anatomical designs, the contact area and pressure increased with the flexion angle. The dome design reached its maximum contact area at a flexion angle of 120°. Among the designs, the anatomical design had the largest contact area and a lower contact pressure compared to the dome and modified dome designs. However, when a medial shift of 2 mm was simulated at a 45° flexion angle, which can occur clinically, the anatomical design showed edge contact, leading to higher contact pressure and reduced contact area. In contrast, the modified dome design demonstrated the lowest contact pressure and the greatest contact area under the same shifted conditions.
Conclusion
These findings suggest that the design of the patellar component significantly affects patellar biomechanics and stability. Specifically, the modified dome design showed improved biomechanical effects in clinically relevant scenarios. Therefore, patellar components with a modified dome design are expected to better manage PF joint pain and reduce complications in TKA.
6.Corrigendum to: Cardioprotection via mitochondrial transplantation supports fatty acid metabolism in ischemia-reperfusion injured rat heart
Jehee JANG ; Ki-Woon KANG ; Young-Won KIM ; Seohyun JEONG ; Jaeyoon PARK ; Jihoon PARK ; Jisung MOON ; Junghyun JANG ; Seohyeon KIM ; Sunghun KIM ; Sungjoo CHO ; Yurim LEE ; Hyoung Kyu KIM ; Jin HAN ; Eun-A KO ; Sung-Cherl JUNG ; Jung-Ha KIM ; Jae-Hong KO
The Korean Journal of Physiology and Pharmacology 2024;28(4):391-391
7.Cardioprotection via mitochondrial transplantation supports fatty acid metabolism in ischemia-reperfusion injured rat heart
Jehee JANG ; Ki-Woon KANG ; Young-Won KIM ; Seohyun JEONG ; Jaeyoon PARK ; Jihoon PARK ; Jisung MOON ; Junghyun JANG ; Seohyeon KIM ; Sunghun KIM ; Sungjoo CHO ; Yurim LEE ; Hyoung Kyu KIM ; Jin HAN ; Eun-A KO ; Sung-Cherl JUNG ; Jung-Ha KIM ; Jae-Hong KO
The Korean Journal of Physiology and Pharmacology 2024;28(3):209-217
In addition to cellular damage, ischemia-reperfusion (IR) injury induces substantial damage to the mitochondria and endoplasmic reticulum. In this study, we sought to determine whether impaired mitochondrial function owing to IR could be restored by transplanting mitochondria into the heart under ex vivo IR states. Additionally, we aimed to provide preliminary results to inform therapeutic options for ischemic heart disease (IHD). Healthy mitochondria isolated from autologous gluteus maximus muscle were transplanted into the hearts of Sprague–Dawley rats damaged by IR using the Langendorff system, and the heart rate and oxygen consumption capacity of the mitochondria were measured to confirm whether heart function was restored. In addition, relative expression levels were measured to identify the genes related to IR injury. Mitochondrial oxygen consumption capacity was found to be lower in the IR group than in the group that underwent mitochondrial transplantation after IR injury (p < 0.05), and the control group showed a tendency toward increased oxygen consumption capacity compared with the IR group. Among the genes related to fatty acid metabolism, Cpt1b (p < 0.05) and Fads1 (p < 0.01) showed significant expression in the following order: IR group, IR + transplantation group, and control group. These results suggest that mitochondrial transplantation protects the heart from IR damage and may be feasible as a therapeutic option for IHD.
8.Effectiveness of the triptorelin stimulation test compared with the classic gonadotropin-releasing hormone stimulation test in diagnosing central precocious puberty in girls
Yu Jin KIM ; Jung HWANGBO ; Kyu Hyun PARK ; Eungu KANG ; Hyo-Kyoung NAM ; Young-Jun RHIE ; Kee-Hyoung LEE
Annals of Pediatric Endocrinology & Metabolism 2024;29(2):90-94
Purpose:
The gonadotropin-releasing hormone (GnRH) stimulation test is the gold standard for diagnosing central precocious puberty (CPP). Gonadorelin (Relefact) is used for the test but is not always readily available; triptorelin is used as an alternative. The purpose of this study was to evaluate the diagnostic validity of the triptorelin test compared with the GnRH test in the diagnosis of CPP in girls.
Methods:
This retrospective study included 100 girls with premature thelarche (PT) who underwent a hypothalamic-pituitary-gonadal axis evaluation. In the overall group, 50 girls were tested with intravenous gonadorelin (Relefact) and 50 girls were tested with subcutaneous triptorelin acetate (Decapeptyl). Luteinizing hormone (LH) and follicle-stimulating hormone levels were measured at baseline and 30, 45, 60, and 90 minutes after gonadorelin injection or 30, 60, 90, and 120 minutes after triptorelin injection.
Results:
Clinical characteristics of age, height, weight, body mass index, and bone age were similar between the 2 groups. The highest LH level was reached 60 minutes after stimulation in both groups. Approximately 20% of the gonadorelin group and 24% of the triptorelin group were diagnosed with CPP (P=0.52). Among those diagnosed with CPP, the mean peak LH concentrations were 8.15 mIU/mL and 9.73 mIU/mL in the gonadorelin and triptorelin groups, respectively.
Conclusion
The triptorelin test showed similar trends of LH elevation and diagnostic rate compared with the traditional GnRH test for diagnosing CPP. This suggests that the triptorelin test may be a valid alternative to the GnRH test for differentiating CPP from self-limiting PT. Our study also demonstrated that a triptorelin stimulation test for up to 120 minutes was sufficient to diagnose CPP.
9.Long-term efficacy of a triptorelin 3-month depot in girls with central precocious puberty
Kyu Hyun PARK ; Si-Hwa GWAG ; Yu Jin KIM ; Lindsey Yoojin CHUNG ; Eungu KANG ; Hyo-Kyoung NAM ; Young-Jun RHIE ; Kee-Hyoung LEE
Annals of Pediatric Endocrinology & Metabolism 2024;29(3):161-166
Purpose:
Three-month gonadotropin-releasing hormone agonists (GnRHas) are expected to achieve better compliance in patients with central precocious puberty (CPP) compared to the monthly formulation. However, 1-month depot remains the dominant choice for conventional treatment worldwide. Our study aimed to investigate the long-term efficacy of a 3-month GnRHa for CPP treatment.
Methods:
In this retrospective study, 69 Korean girls with CPP were prescribed either triptorelin pamoate (TP) 3-month depot (n=29) or triptorelin acetate (TA) 1-month depot (n=40) and were followed for 1 year after the end of treatment. Auxological, radiological, and biochemical data were collected every 6 months.
Results:
Baseline characteristics were similar between the 2 groups. In the TP 3-month depot group, 27 of 29 patients (93.1%) exhibited suppressed luteinizing hormone level (below 2.5 IU/L) after 6 months of treatment, and this suppression level was reserved until the final injection. The degree of bone age advancement in the TP 3-month depot group decreased from 1.8±0.4 years at the start of treatment to 0.6±0.5 years at 1-year posttreatment. The gain in predicted adult height (PAH) 1 year after the end of treatment was similar between the TP 3-month and TA 1-month depot groups (5.2±3.1 and 5.3±2.4 cm, respectively; p=0.875).
Conclusion
A 3-month depot of triptorelin effectively inhibited gonadal and sex hormones, suppressed bone maturation, and increased PAH. For patient convenience, we suggest a 3-month GnRHa regimen as a promising CPP treatment option.
10.Safety and Effectiveness of Dulaglutide in the Treatment of Type 2 Diabetes Mellitus: A Korean Real-World Post-Marketing Study
Jeonghee HAN ; Woo Je LEE ; Kyu Yeon HUR ; Jae Hyoung CHO ; Byung Wan LEE ; Cheol-Young PARK
Diabetes & Metabolism Journal 2024;48(3):418-428
Background:
To investigate the real-world safety and effectiveness of dulaglutide in Korean adults with type 2 diabetes mellitus (T2DM).
Methods:
This was a real-world, prospective, non-interventional post-marketing safety study conducted from May 26, 2015 to May 25, 2021 at 85 Korean healthcare centers using electronic case data. Data on patients using dulaglutide 0.75 mg/0.5 mL or the dulaglutide 1.5 mg/0.5 mL single-use pens were collected and pooled. The primary objective was to report the frequency and proportion of adverse and serious adverse events that occurred. The secondary objective was to monitor the effectiveness of dulaglutide at 12 and 24 weeks by evaluating changes in glycosylated hemoglobin (HbA1c ), fasting plasma glucose, and body weight.
Results:
Data were collected from 3,067 subjects, and 3,022 subjects who received ≥1 dose (of any strength) of dulaglutide were included in the safety analysis set (53% female, mean age 56 years; diabetes duration 11.2 years, mean HbA1c 8.8%). The number of adverse events reported was 819; of these, 68 (8.3%) were serious adverse events. One death was reported. Adverse events were mostly mild in severity; 60.81% of adverse events were considered related to dulaglutide. This study was completed by 72.73% (2,198/3,022) of subjects. At 12/24 weeks there were significant (P<0.0001) reductions from baseline in least-squares mean HbA1c (0.96%/0.95%), fasting blood glucose (26.24/24.43 mg/dL), and body weight (0.75/1.21 kg).
Conclusion
Dulaglutide was generally well tolerated and effective in real-world Korean individuals with T2DM. The results from this study contribute to the body of evidence for dulaglutide use in this population.

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