Chang-Jin Yon

Prof. Dr. Chang-Jin Yon

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 April 2022 in Diagnostics
Verified
Journal Article
Open access
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Kwang-Rak ParkKwang-Rak Park
Kwang-Rak Park
JLJae-Ho Lee
Jae-Ho Lee
DKDae-soo Kim
Dae-soo Kim
HRHo Ryu
Ho Ryu
JKJaeho Kim
Jaeho Kim
SLSi-Wook Lee
Si-Wook Lee
Background and objectives: The differences between computed radiography-based teleoroentgenograms (CR-based teleoroentgenograms) and an EOS® imaging system were evaluated by measuring lower extremity lengths and alignments. Materials and methods: The leg length [L], femur length [F], tibia length [T], and hip–knee–ankle (HKA) angle were measured in 101 patients with lower extremity disease by a CR-based teleoroentgenogram with computed radiography and an EOS®. The additive length of the femoral and tibial segments (F + T) was determined by adding the two length values. Then, the differences among all five parameters between the two techniques were analyzed. The magnification (mm) was calculated by subtracting the length measurements on the EOS® from those in the scanogram. Furthermore, the magnification percentage (%) was calculated by dividing the magnification with the measurements on the EOS®. Results: The magnification errors (mean ± standard deviation), when comparing both right and left sides, were 7.80 ± 1.41%, 7.3 ± 6.01%, 5.16 ± 1.25%, and 6.45 ± 0.94% for L, F, T, and F + T, respectively. For limb length, the CR-based teleoroentgenogram had an average magnification of 6.8% (range, 5.2 to 7.8%) compared to the EOS® imaging. The two groups displayed a statistical difference (p < 0.01), except for the HKA angle. Conclusions: The CR-based teleoroentgenogram had a magnification of about 6.8% compared to the EOS® imaging system in evaluating lower extremity length. Therefore, more attention must be given to CR-based teleoroentgenograms to correct angular deformities.

25 October 2020 in Journal of Clinical Medicine
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Journal Article
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CYChang-Jin Yon
Chang-Jin Yon
Chul-Hyun ChoChul-Hyun Cho
Chul-Hyun Cho
DKDu Hwan Kim
Du Hwan Kim
Although the frequency of arthroscopic revision surgery is increasing in patients with recurrent dislocation after a primary shoulder stabilization, the literature describing arthroscopic revision Bankart repair has been limited. Preferred reporting items for systematic meta-analyses guidelines were followed by utilizing PubMed, EMBASE, Scopus, and Cochrane Library databases. Keywords included shoulder dislocation, anterior shoulder instability, revision surgery, stabilization, and arthroscopic Bankart repair. Quality assessments were performed with criteria from the methodological index for nonrandomized studies (MINORS). A total of 14 articles were included in this analysis. The mean MINORS score was 12.43. A total of 339 shoulders (337 patients) were included (281 males and 56 females). The mean follow-up period was 36.7 months. Primary surgeries were as follows: arthroscopic procedures (n = 172, 50.7%), open procedure (n = 87, 25.7%), and unknown (n = 80, 23.6%). The mean rate of recurrent instability after revision arthroscopic Bankart repair was 15.3% (n = 52), and an additional re-revision procedure was needed in 6.5% of cases (n = 22). Overall, there were 18.0% (n = 61) of complications reported. This systematic review suggests that arthroscopic revision Bankart repair can lead to an improvement in functional outcomes and reasonable patient satisfaction with proper patient selection.

Verified
Journal Article
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CYChang-Jin Yon
Chang-Jin Yon
BCByung-Chan Choi
Byung-Chan Choi
JLJung-min Lee
Jung-min Lee
SLSi-Wook Lee
Si-Wook Lee
Three-dimensional (3D)-printing technology is revolutionizing orthopedic oncology by providing precise, customized solutions for complex bone defects following tumor resection. Traditional modular endoprostheses are prone to complications such as fretting corrosion and implant failure, underscoring the need for innovative approaches. This case series reports on three patients treated with 3D-printed, patient-specific prostheses and cutting guides. Preoperative CT and MRI data were used to design implants tailored to each patient’s anatomy, manufactured using electron beam melting technology with a titanium–aluminum–vanadium alloy. Functional outcomes showed significant improvements: in Case I, AOFAS improved from 71 to 96, and VAS decreased from 6 to 1; in Case II, AOFAS increased from 65 to 79, and VAS decreased from 5 to 3. Radiographic evaluations demonstrated stable prosthesis placement and early evidence of bone integration in Cases I and II, while in Case III, localized disease control was achieved before systemic progression. This case series highlights the transformative potential of 3D-printed prostheses in addressing the challenges of reconstructing anatomically complex defects. By enabling precise tumor resection and improving functional outcomes, this approach can advance current practices in orthopedic oncology. Further research should explore larger cohorts and use cost-effectiveness analyses to validate these findings and facilitate broader clinical adoption.

18 December 2020 in Journal of Clinical Medicine
Verified
Journal Article
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SLSi Wook Lee
Si Wook Lee
KLKyung-Jae Lee
Kyung-Jae Lee
Chul-Hyun ChoChul-Hyun Cho
Chul-Hyun Cho
HYHee-Uk Ye
Hee-Uk Ye
CYChang-Jin Yon
Chang-Jin Yon
KSKwang-Soon Song
Kwang-Soon Song
This study evaluated the correction rates of idiopathic genu valgum or varum after percutaneous epiphysiodesis using transphyseal screws (PETS) and analyzed the affecting factors. A total of 35 children without underlying diseases were enrolled containing 64 physes (44 distal femoral (DT), 20 proximal tibial (PT)). Anatomic tibiofemoral angle (aTFA) and the mechanical axis deviation (MAD) were taken from teleroentgenograms before PETS surgery and screw removal. The correction rates of the valgus and varus deformities for patients treated with PETS were 1.146°/month and 0.639°/month using aTFA while using MAD showed rates of 4.884%/month and 3.094%/month. After aTFA (p < 0.001) and MAD (p < 0.001) analyses, the correction rate of DF was significantly faster than that of PT. Under multivariable analysis, the aTFA correction rate was significantly faster in younger patients (p < 0.001), in males (p < 0.001), in patients with lower weights (p < 0.001), and in the group that was screwed at DF (p < 0.001). Meanwhile, the MAD correction rate was significantly faster in patients with lower heights (p = 0.003). PETS is an effective treatment method for valgus and varus deformities in growing children and clinical characters should be considered to estimate the correction rate.

28 July 2022 in Diagnostics
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Journal Article
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KSKwang-Soon Song
Kwang-Soon Song
CYChang-Jin Yon
Chang-Jin Yon
YHYU-RAN HEO
YU-RAN HEO
JLJae-Ho Lee
Jae-Ho Lee
SLSeung-Bo Lee
Seung-Bo Lee
SLSi Wook Lee
Si Wook Lee
Twenty-five cadaveric adult femora’s anteversion angles were measured to develop a highly efficient and reproducible femoral anteversion measurement method using computed tomography (CT). Digital photography captured the proximal femur’s two reference lines, head-to-neck (H-N) and head-to-greater trochanter (H-G). Six reference lines (A/B in transverse section; C, axial oblique section; D/E, conventional 3D reconstruction; and M, volumetric 3D reconstruction) from CT scans were used. The posterior condylar line was used as a distal femoral reference. As measured with the H-N and H-G lines, the anteversion means were 10.43° and 19.50°, respectively. Gross anteversion measured with the H-G line had less interobserver bias (ICC; H-N = 0.956, H-G = 0.982). The 2D transverse and volumetric 3D CT sections’ B/M lines were consistent with the H-N line (p: B = 0.925, M = 0.122) and the 2D axial oblique section’s C line was consistent with the H-G line (p < 0.1). The D/E lines differed significantly from the actual gross images (p < 0.05). Among several CT scan femoral anteversion measurement methods, the novel anteversion angle measurement method using CT scans’ axial oblique section was approximated with actual gross femoral anteversion angle from the femoral head to the greater trochanter.

2 December 2024 in Medicina
Verified
Journal Article
Open access
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KBKi-Cheor Bae
Ki-Cheor Bae
ESEun-Seok Son
Eun-Seok Son
CYChang-Jin Yon
Chang-Jin Yon
JPJubin Park
Jubin Park
DKDu Hwan Kim
Du Hwan Kim
Background and Objectives: Despite extensive studies of the role of quadriceps and quadriceps/hamstring balance in knee osteoarthritis (OA), the roles of the vastus intermedius, medialis, and lateralis in OA remain unclear. The purpose of this study was to investigate the relationship of lower limb alignment and the ratio of the quadriceps femoris muscle to the knee extensor muscle. Materials and Methods: This study included 50 patients with advanced knee OA (Kellgren/Lawrence grade of 3 or 4) and 25 healthy control persons between June 2021 and May 2022. The osteoarthritis grade and anatomical tibiofemoral angle were measured based on plain radiography and scanography. All participants were divided into normal (0~5°), mild varus (5°~10°), and severe varus (>10°) groups. Using MRI, muscle size was determined by calculating the cross-sectional area (CSA) of the total quadriceps (rectus femoris, vastus intermedius, vastus medialis, and vastus lateralis) and its components. Results: The CSA ratio of the vastus lateralis was significantly smaller in the severe varus group than in the normal or mild varus groups. There was a significant positive correlation between the mechanical tibiofemoral angle and vastus lateralis CSA (ρ = 0.282, p = 0.014) and between the anatomical tibiofemoral angle and vastus lateralis CSA (ρ = 0.294, p = 0.011). There was a significant negative correlation between the mechanical tibiofemoral angle and vastus intermedius CSA (ρ = −0.263, p = 0.023) and between the anatomical tibiofemoral angle and vastus intermedius CSA (ρ = −0.243, p = 0.036). Conclusions: Patients with severe varus alignment exhibited vastus lateralis atrophy. This study highlights vastus lateralis atrophy in severe varus alignment, though causality between atrophy and varus knee OA remains uncertain. We think that patients with severe varus may require strengthening exercises focused on the vastus lateralis before and after surgery for alignment correction.