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.

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.

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.

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.

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.

Purpose: We examined the association between age-related macular degeneration (AMD) and arthritis. Methods: Using data from the Korea National Health and Nutrition Examination Survey for 2017 and 2018, we conducted a complex sample analysis of 6,993 individuals with recorded information on AMD, as well as the diagnosis and treatment of osteoarthritis (OA) and rheumatoid arthritis (RA). We compared the diagnosis and treatment of arthritis between the AMD and control groups using logistic regression analysis, with a specific focus on the treatment among patients with arthritis. Results: In the AMD group (n = 1,118) and the control group (n = 5,875), univariate logistic regression analysis showed substantial differences in the diagnosis and treatment of OA and RA. However, after adjusting for age, alcohol consumption, diabetes mellitus, and hypertension in multivariate logistic regression analysis, these differences were no longer substantial. Among patients with OA (n = 246 in the AMD group and n = 821 in the control group), there was a significant association between AMD and OA treatments (odds ratio 1.511, 95% confidence interval 1.051-2.172). Conclusions Patients diagnosed with and treated for OA had a higher likelihood of concurrent AMD than those who did not receive treatment. Therefore, ophthalmic examinations and closer monitoring are recommended for these patients.

Purpose: To analyze the incidence of vitreous floaters after intravitreal antivascular endothelial growth factor injection and the effectiveness of the inverse tapping technique, which involves tapping the syringe with the needle downwards to prevent the entry of air bubbles during injection. Methods: The study enrolled patients undergoing their first intravitreal injection for exudative age-related macular degeneration or diabetic macular edema. The patients were divided into two groups: those who received an injection after inverse tapping (IT group) and controls who received the injection without tapping. Patients who consented to the study were randomly assigned to the IT group and the control group through block randomization. One week after injection, a questionnaire was used to assess the presence of vitreous floaters; those who reported them were examined via optical coherence tomography and wide fundus photography. Results: Of the 39 patients in the IT group, two (5.1%) reported floaters 1 week after injection. By contrast, eight (20.5%) of the 39 controls reported them, with a significant difference (p = 0.042). Patients with floaters were significantly younger. Posterior vitreous detachment, as evaluated by pre-injection optical coherence tomography, was observed in 10.0% of those with floaters and 76.5% of those without them. Conclusions The occurrence of vitreous floaters after intravitreal injection is related to age and the presence of posterior vitreous detachment. The use of the inverse tapping technique may help reduce these after intravitreal injection.

Purpose: High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard management for relapsed or high-risk non-Hodgkin’s lymphoma (NHL). We reported the busulfan, melphalan, and etoposide (BuME) conditioning regimen was effective in patients with relapsed or high-risk NHL. Moreover, the busulfan, cyclophosphamide, and etoposide (BuCE) conditioning regimen has been used widely in ASCT for NHL. Therefore, based on these encouraging results, this randomized phase II multicenter trial compared the outcomes of BuME and BuCE as conditioning therapies for ASCT in patients with NHL. Materials and Methods: Patients were randomly assigned to receive either BuME (n=36) or BuCE (n=39). The BuME regimen was comprised of busulfan (3.2 mg/kg/day, intravenously) administered on days –7, –6, and –5, etoposide (400 mg/m2 intravenously) on days –5 and –4, and melphalan (50 mg/m2/day intravenously) on days –3 and –2. The BuCE regimen was comprised of busulfan (3.2 mg/kg/day intravenously) on days –7, –6, and –5, etoposide (400 mg/m2/day intravenously) on days –5 and –4, and cyclophosphamide (50 mg/kg/day intravenously) on days –3 and –2. The primary endpoint was 2-year progression-free survival (PFS). Results: Seventy-five patients were enrolled. Eleven patients (30.5%) in the BuME group and 13 patients (33.3%) in the BuCE group had disease progression or died. The 2-year PFS rate was 65.4% in the BuME group and 60.6% in the BuCE group (p=0.746). There were no non-relapse mortalities within 100 days after transplantation. Conclusion There were no significant differences in PFS between the two groups. Therefore, busulfan-based conditioning regimens, BuME and BuCE, may be important treatment substitutes for the BCNU-containing regimens.

The Korean Society of Otorhinolaryngology-Head and Neck Surgery and Korean Rhinologic Society appointed a guideline development group (GDG) to establish a clinical practice guideline, and the GDG developed a guideline for nasal irrigation for adult patients with chronic rhinosinusitis (CRS). The guideline focuses on knowledge gaps, practice variations, and clinical concerns associated with nasal irrigation. Nasal irrigation has been recommended as the first-line treatment for CRS in various guidelines, and its clinical effectiveness has been demonstrated through a number of studies with robust evidence. However, no guidelines have presented a consistent nasal irrigation method. Several databases, including OVID Medline, Embase, the Cochrane Library, and KoreaMed, were searched to identify all relevant papers using a predefined search strategy. When insufficient evidence was found, the GDG sought expert opinions and attempted to fill the evidence gap. Evidence-based recommendations for practice were ranked according to the American College of Physicians grading system. The committee developed 11 evidence-based recommendations. This guideline focuses on the evidence-based quality improvement opportunities deemed the most important by the GDG. Moreover, the guideline addresses whether nasal lavage helps treat CRS, what type of rinsing solution should be used, and the effectiveness of using additional medications to increase the therapeutic effect.

Background and Objectives: The aim of this study was to compare adherence to positive airway pressure (PAP) therapy in patients with obstructive sleep apnea (OSA) of different severity.Subjects and Method We conducted a retrospective study including 270 adult OSA patients who used a PAP device for at least 3 months. We assessed the percentage of days on which the device was used, the percentage of days on which the device was used for ≥4 h, and the average duration of PAP device usage at 12 weeks of PAP therapy. We also evaluated adequate adherence to PAP therapy using a PAP device for ≥4 h/day and during ≥70% of nights. Results: The percentage of days on which a PAP device used did not differ significantly according to OSA severity (median [Q1-Q3]; mild: 91.40% [81.25%-97.65%], moderate: 94.50% [86.90%-100%], severe: 95.90% [88.10%-100%], p=0.268). We also found that the percentage of days on which a PAP device was used during sleep for ≥4 h was not significantly different in patients with different OSA severity (median [Q1-Q3], mild: 76.20% [69.70%-89.90%], moderate: 89.30% [67.65%-95.70%], severe: 85.70% [75.85%-95.45%], p=0.097). The percentage of patients with adequate PAP adherence did not differ significantly according to OSA severity (mild: 74.2%, moderate: 72.1%, severe: 83.0%, p=0.084). Moreover, the mean duration (minutes) of PAP device usage during sleep did not differ significantly according to OSA severity in the mild, moderate, and severe OSA groups (mean±standard deviation, mild: 348.03± 47.78 min, moderate: 358.58±85.22 min, severe: 363.79±57.21 min, p=0.440). Conclusion Adherence to PAP therapy did not differ significantly according to OSA severity. Therefore, it is necessary to continuously expand and maintain the insurance for health promotion in OSA patient in South Korea.