Publications by authors named "ChangWan Kim"
In real-world driving scenarios of electric vehicles, the C-rate fluctuates with changes in speed, and a Battery Thermal Management System (BTMS) design that does not account for a range of C-rates may fail to ensure thermal safety of the battery. In this study, we statistically analyzed the effects of cooling plate geometry and coolant velocity on battery thermal behavior using Design of Experiments (DoE) and Analysis of Variance (ANOVA) across various C-rates. The ANOVA results by C-rate demonstrate that the influence of design factors on BTMS thermal behavior varies with the C-rate.
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- This study aimed to analyze how changes in knee joint geometry after medial open-wedge high tibial osteotomy (MOWHTO) affect patient satisfaction and clinical outcomes over a follow-up period of more than two years.
- Researchers examined the outcomes of 101 knees, comparing the radiological and functional results of patients who were satisfied with their surgery against those who were not.
- The findings revealed that greater postoperative distal tibial rotation correlated with dissatisfaction, indicating that excessive tibial rotation, particularly with larger correction angles, should be minimized during MOWHTO to improve patient outcomes.
Type of medial meniscus tear does not affect the clinical and radiological outcomes of medial opening-wedge high tibial osteotomy.
Knee Surg Sports Traumatol Arthrosc
November 2023
Purpose: The current study aimed to evaluate the effect of medial meniscus posterior root tear (MMPRT) on radiological and clinical outcomes after medial opening-wedge high tibial osteotomy (MOWHTO).
Methods: This retrospective cohort study included patients who underwent MOWHTO (113 knees) at our hospital between September 2012 and June 2020 and who were followed up for > 2 years. The radiological and clinical outcomes were compared between the MMPRT group (52 knees), who included patients with MMPRT, and the non-MMPRT group (61 knees), who comprised patients without meniscal tear or with any type of meniscal tear other than MMPRT.
Background: The causes of primary total knee arthroplasty (TKA) failure can be divided into septic and aseptic etiologies. It is unclear whether the etiology affects the infection rate after revision TKA. This systematic review was conducted to evaluate whether there is a difference in infection rates between septic and aseptic revision TKA.
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- - The study investigated the prevalence and effects of occult pneumothorax in blunt trauma patients at a trauma center between 2020 and 2022, emphasizing that standard chest X-rays may miss this condition, which can be serious if untreated.
- - Among 1621 patients, 187 with blunt chest trauma were analyzed, revealing that 71.7% of pneumothorax cases were occult, with a total incidence of 5.0% in all admitted trauma victims.
- - Key risk factors included subcutaneous emphysema and rib fractures seen on chest X-rays; while some patients required delayed treatment, outcomes were generally positive, suggesting effective follow-up care is crucial.
Introduction: The purpose of this study was to evaluate factors that affect range of motion (ROM) following two-stage revision arthroplasty as a treatment for chronic periprosthetic knee infection.
Materials And Methods: A total of 98 patients diagnosed with chronic periprosthetic joint infection (PJI) following primary total knee arthroplasty between January 2009 and December 2019 and then underwent two-stage revision arthroplasty were reviewed retrospectively. Multiple regression analysis was performed to evaluate the factors that affect ROM after two-stage revision arthroplasty.
Intra-Articular Injection of a Novel DVS Cross-Linked Hyaluronic Acid Manufactured by Biological Fermentation (YYD302) in Patients With Knee Osteoarthritis: A Double-Blind, Randomized, Multicenter, Noninferiority Study.
Clin Ther
November 2021
Purpose: This double-blind, randomized, Phase III clinical trial was conducted to assess the efficacy and safety of the novel divinyl sulfone cross-linked hyaluronate (YYD302) compared with the 1,4-butanediol diglycidyl ether cross-linked hyaluronate (Synovian) in patients with knee osteoarthritis.
Methods: A total of 184 patients with osteoarthritis (Kellgren-Lawrence grade I-III) were randomized to 1 of 2 study groups (YYD302 group, n = 95; Synovian group, n = 89). A single injection of YYD302 or Synovian was given to both groups, and 182 participants completed the study (YYD302 group, n = 95; Synovian group, n = 87).
Background: The effect of negative culture on the treatment outcomes of chronic periprosthetic joint infection (PJI) is still controversial. The purpose of this study is to evaluate whether the outcomes of two-stage revision in culture-negative chronic PJI differ from those in culture-positive PJI.
Methods: The patients who received two-stage revisions due to chronic PJI during the period between 2007 and 2017 were retrospectively reviewed.
Article Synopsis
- The study focuses on improving the specific energy density of lithium-ion batteries (LIB) for electric vehicles by using optimization methods.
- Researchers utilized design experiments to assess key factors such as electrode thickness, porosity, and particle size affecting battery performance.
- By applying the progressive quadratic response surface method (PQRSM), they achieved a 56.8% increase in specific energy density and reduced polarization by 11.5% while ensuring that power density remained acceptable.
Background: Many reports have described the relationship between medial meniscus posterior root tears (MMPRTs) and meniscal extrusion on coronal magnetic resonance (MR) images. However, volumetric assessment of meniscal extrusion has not been performed, and the correlation between extrusion length and volume remains unclear.
Hypothesis: Extrusion in both length and volume would be greater in MMPRTs than that in the normal medial meniscus, and the extrusion length measured on coronal MR images would be correlated with the extrusion volume.
Purpose: To compare the differences with respect to clinical and graft survivorship and patient-reported outcomes (PROs) between lateral (LMAT) and medial (MMAT) meniscus allograft transplantation.
Methods: Patients having a primary MAT between 1998 and 2016 were enrolled. The inclusion criteria were (1) patients who had a minimum 2-year follow-up and (2) patients who had magnetic resonance imaging (MRI) >2 years after surgery.
Background: The purpose of this study was to evaluate the effect of patellar facet angle on pre- and postoperative patellofemoral alignment and the progress of arthritis of the patellofemoral joint in posterior-stabilized total knee arthroplasty (PS TKA) without patellar resurfacing.
Methods: Patients who had a PS TKA for a varus osteoarthritic knee who were followed up for more than 2 years were included in this study. The radiologic and clinical outcomes were compared between 72 knees (group A) whose patellar facet angle was greater than 126° (> 126°) and 32 knees (group B) whose patellar facet angle was smaller than or equal to 126° (≤ 126°).
Background: This meta-analysis was conducted to evaluate the differences in preoperative comorbidities, postoperative mortality, the rate of periprosthetic joint infection (PJI), and revision rate after total joint arthroplasty (TJA) between patients with chronic kidney disease (CKD)(CKD group) and patients with normal kidney function (non-CKD group).
Methods: We searched MEDLINE, EMBASE, and the Cochrane Library for studies assessing the effect of CKD on TJA outcome. This meta-analysis included studies that (1) compared the outcomes of TJA between the CKD and non-CKD groups; (2) compared the outcomes of TJA based on CKD stage; and (3) evaluated the risk factors for morbidity or mortality after TJA.
Article Synopsis
- Arthroscopic labral repair and capsular plication help reduce joint size and improve the glenoid labral bumper height, potentially affecting the results over time.
- The study aimed to quantify these variables through computed tomography arthrography (CTA) and compare them between patients with and without post-surgery apprehension.
- Results showed that there was a significant relationship between glenoid labral bumper height and joint volume, with notable differences in joint volume fractions between patients showing apprehension and those who did not.
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.
Background: Femoral coronal bowing (FCB) has been reported to be a risk factor for mechanical malalignment after total knee arthroplasty (TKA). However, the effects of FCB on the long-term survivorship (when postoperative mechanical alignment (MA) is neutral after TKA) have not been determined.
Hypothesis: The effects of FCB on the cumulative survivorship after TKA may be significantly smaller compared with those of MA.
Introduction: The purpose of this study was to evaluate the healing rate of repaired meniscus and functional outcomes of patients who received all-inside meniscal repair using sutures or devices with concomitant arthroscopic anterior cruciate ligament (ACL) reconstruction.
Materials And Methods: Among the patients who have ACL tear and posterior horn tear of medial or lateral meniscus, 61 knees who received all-inside repair using sutures (suture group, n = 28) or meniscal fixation devices (device group, n = 33) with concomitant ACL reconstruction during the period from January 2012 to December 2015, followed by second-look arthroscopy, were retrospectively reviewed. Healing status of the repair site was assessed by second-look arthroscopy.
Background: The aim of this study was to compare the functional outcomes and recurrence rate of infection between patients who underwent arthroscopic surgery and two-stage total knee arthroplasty (TKA) for infected arthritic knees.
Methods: A retrospective analysis was conducted on 52 patients (52 knees) with advanced knee joint arthritis who underwent arthroscopic surgery or two-stage TKA using articulating cement spacer (ACS) for knee joint infection between January 2009 and November 2013. Of the 52 patients (52 knees), 38 and 14 patients underwent arthroscopic surgery (AS group) and two-stage TKA using ACS (ACS-TKA group), respectively.
Purpose: To evaluate the effect of using intraoperative fluoroscopy on femoral and tibial tunnel positioning variability in single-bundle anterior cruciate ligament (ACL) reconstruction.
Methods: A total of 80 consecutive patients with single-bundle ACL reconstruction between 2014 and 2016 were retrospectively reviewed. Among them, 40 underwent ACL reconstruction without fluoroscopy (non-fluoroscopy group) and 40 underwent fluoroscopy-assisted ACL reconstruction (fluoroscopy group).
Purpose: To compare radiologic and clinical outcomes between patients who underwent medial meniscus posterior root tear (MMPRT) repair and were subsequently classified as having lax healing based on second-look arthroscopy and patients who underwent subtotal meniscectomy for an MMPRT.
Methods: The patients who received pullout repair or subtotal meniscectomy due to MMPRT between January 2011 and December 2014 were retrospectively reviewed. Among the patients who underwent MMPRT repair, those whose lax healing of the repair site was confirmed by second-look arthroscopy (repair/lax healing group) and among the patients who received subtotal meniscectomy, those who have varus deformity of <5° and a Kellgren-Lawrence grade of ≤2 (meniscectomy group) were included in the study population.
Background: It is not clear whether long-term outcomes differ between computer-navigated and conventional total knee arthroplasty. The purpose of this study was to perform a meta-analysis comparing the radiographic outcomes, the long-term functional outcomes, and survivorship between computer-navigated total knee arthroplasty and conventional total knee arthroplasty.
Methods: We searched MEDLINE, Embase, and the Cochrane Library to identify studies comparing long-term outcomes between computer-navigated total knee arthroplasty and conventional total knee arthroplasty.
Background: Minimal rotation of the scapula may affect the measurement of critical shoulder angle (CSA). We investigated the difference in the CSA measured in minimal rotation between the patients with rotator cuff tear and those without non-rotator cuff tear and the CSA measurement error by comparing with computed tomography (CT).
Methods: We retrospectively reviewed patients with full-thickness rotator cuff tear and whose X-ray views correspond to Suter-Henninger classification type A1 and C1.
Introduction: To evaluate the long-term survival of unicompartmental knee arthroplasty (UKA) in the Asian population and assess differences in clinical outcomes between mobile- and fixed-bearing UKA.
Materials And Methods: Among 111 cases of UKA that were performed by 1 surgeon from January 2002 to December 2009, we retrospectively reviewed 96 cases (36 mobile-bearing, 62 fixed-bearing) for this study. We examined cause of revision or failure, type of reoperation/revision, and duration from the surgery date to the revision upon reviewing the medical record.
Background: The purpose of this study was to measure the distance of the clavicle in 3 dimensions (3D) and each direction (anterior to posterior, medial to lateral, and superior to inferior) and to analyze the correlation of the angular orientation of the scapula according to each directional distance of the clavicle.
Methods: Sixty-seven patients with Robinson 2B1 and 2B2 clavicle midshaft fracture (46.0 ± 17.