YYYoon Seok Youm

Yoon Seok Youm

*This is an algorithmically generated author record based on publicly available information.

Current Organizations / Institutes

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Previous Organizations / Institutes

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Yoon Seok Youm has a total of 70 co-authors. Here are the top co-authors by number of shared publications:

  • Sung Do Cho

    Department of Orthopedic Surgery, Dongcheondongkang Hospital, Ulsan, South Korea

    7 shared publications
  • Sung-Do Cho

    Department of Orthopedic Surgery, Dongcheondongkang Hospital, Ulsan, Korea

    3 shared publications
  • Sung-Do Cho

    Department of Orthopedic Surgery, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea

    3 shared publications
  • Chang Ho Hwang

    Department of Physical and Rehabilitation Medicine, Chungnam National University Sejong Hospital, College of Medicine, Chungnam National University, Sejong, Republic of Korea

    2 shared publications
  • Ki-Bong Park

    Department of Orthopedic Surgery, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, Korea

    2 shared publications
  • Ki‐Bong Park

    Department of Orthopedic Surgery Ulsan University Hospital University of Ulsan College of Medicine Ulsan South Korea

    2 shared publications

Latest Publications

  • Open Access

    Distal Femur Fractures Treated with Distal Femoral Locking Plate Fixation: A Retrospective Study of One Year Mortality and Risk Factors

    by Kwang-Hwan Jung, Yoon-Seok Youm, Seung-Hyun Jung, Jae-Min Oh, Ki Bong Park

    정광환, et al. J Korean Fract Soc. 2023 Jan;36(1):10-16. https://doi.org/10.12671/jkfs.2023.36.1.10

  • Open Access

    Preoperative vitamin D level does not affect the short-term functional outcome after total knee arthroplasty in elderly women

    by Il Yeong Hwang, Ki Bong Park, Sung Who Chang, Sung Do Cho, Yoon Seok Youm

    Background: We aimed to evaluate the effect of vitamin D levels on the functional outcome of elderly women who underwent total knee arthroplasty (TKA). Methods: Seven hundred and four patients (1013 knees) who underwent primary TKA were included in our retrospective study. Preoperative vitamin D levels were measured and the relationship analyzed between these and age, weight, height, body mass index, and bone mineral density. Two hundred and twenty patients (220 knees) who received unilateral TKA and were followed up for more than 1 year after operation were divided into two groups: Group 1, serum 25-hydroxyvitamin D3 (25(OH)D3) level < 20 ng/ml; and Group 2, 25(OH)D3 level ≥ 20 ng/ml. Both groups were evaluated for the relationship between vitamin D levels and postoperative Visual Analogue Scale (VAS) score, Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) score. Results: The number of vitamin D-deficient patients (< 20 ng/ml of serum 25(OH)D3 level) was 556 (79.0%). In the correlation analysis, the vitamin D level was negatively correlated with weight only (p = 0.033). No significant differences were observed between the groups in terms of postoperative VAS score, KSKS, KSFS, and WOMAC score. Conclusions: Vitamin D deficiency was highly prevalent in patients who underwent TKA. Vitamin D levels negatively correlated with weight. Low vitamin D level was not a risk factor for unsatisfactory TKA outcome in elderly women.


  • Open Access

    Does posterior tibial slope affect the results of conservative treatment for anterior cruciate ligament tears?

    by Ki Bong Park, Sung Do Cho, Yoon Seok Youm, Doo Guen Yang, Hee Yoon Chung

    Objective To evaluate the association between posterior tibial slope (PTS) and the short-term results of conservative treatment for the patients with anterior cruciate ligament (ACL) tears. Methods Thirty-seven patients (37 knees: male 33, female 4) who were managed with the same treatment protocols for ACL tears were included. All patients applied ACL brace and underwent standardized rehabilitation protocol. Group A consisted of 14 patients with successful results after conservative management and group B consisted of 23 patients who received operative treatments due to failed conservative management. For each group, a plain radiograph was used to measure the PTS. The demographic data of patients and differences of PTS between each group were analyzed. Results The mean age was 33.2 years in group A and 29.7 years in group B, respectively (p = 0.8). There was no significant difference between each group in terms of gender, body mass index, and injury mechanism. There was no significant difference between each group in the classification according to the isolated or combined injury (p = 0.83). The mean PTS was 8.3° in group A and 10.2° in group B. The mean PTS in group A was significantly lower than that in group B (p = 0.03). Conclusions The patients with successful results after conservative management had a lower mean PTS than those with failed conservative treatment (8.3° vs. 10.2°, p = 0.03). The failure of conservative treatment after ACL tear was found to be associated with increased PTS.


  • Pigmented villonodular synovitis after anterior cruciate ligament reconstruction using active bioprosthetic composite artificial ligament

    by Sung Do Cho, Yoon Seok Youm, Sun Jae Park, Hyung In Cho

    Pigmented villonodular synovitis (PVNS) is a proliferative disease that develops in the synovium of joints, especially the knee joints. A 52-year-old man visited our hospital with left knee pain, swelling and symptoms of collapse. Twenty-one years earlier, he had undergone anterior cruciate ligament (ACL) reconstruction using an active bioprosthetic composite (ABC) as an artificial ligament. T1 and T2 weighted magnetic resonance imaging of the knee joint showed rupture of the ABC ligament and low signal intensity of hyperplastic synovium. Arthroscopic total synovectomy without ACL reconstruction was performed and the lesion was histopathologically diagnosed as diffuse PVNS. Clinical outcomes included good pain relief and no recurrence of the disease after 5 years of follow-up.


  • Iatrogenic Medial Collateral Ligament Injury by Valgus Stress During Arthroscopic Surgery of the Knee

    by Kwang Hwan Jung, Yoon Seok Youm, Sung Do Cho, Woo Young Jin, Sun Hwan Kwon

    Purpose: To evaluate the radiographic and clinical follow‐up results of iatrogenic medial collateral ligament (MCL) injuries caused by valgus stress during arthroscopic surgery of the knee. Methods: This study retrospectively evaluated 15 knees in 15 patients (8 female and 7 male patients), with a mean age of 58 years (range, 45‐66 years), with iatrogenic MCL injuries caused by valgus stress during arthroscopic surgery of the knee. All patients were treated conservatively without an immobilizer or brace. The mean follow‐up period was 24 months (range, 18‐51 months). Evaluations included magnetic resonance imaging immediately postoperatively, as well as physical examinations and valgus stress radiographs (at 0° and 30° of knee flexion) 6 weeks after surgery and at final follow‐up. Results: Postoperative magnetic resonance imaging in all patients showed increased signal intensity, swelling, and partial loss of continuity at the meniscofemoral portion of the MCL. Physical examination showed mild tenderness in only 1 patient after 6 weeks and none at final follow‐up. Valgus stress tests and valgus stress radiographs showed no significant differences between the injured and uninjured knees at 6 weeks postoperatively and at final follow‐up ( P > .05). Conclusions: Iatrogenic MCL injuries during arthroscopic knee surgery could be treated successfully without a splint or brace. Level of Evidence: Level IV, prognostic case series.


  • Does Posterior Tibial Slope Affect Graft Rupture Following Anterior Cruciate Ligament Reconstruction?

    by Chae Chil Lee, Yoon Seok Youm, Sung Do Cho, Seung Hyun Jung, Mun Hee Bae, Seon Jae Park, Han Wook Kim

    Purpose: The purpose of this study was to evaluate the association between posterior tibial slope (PTS) and anterior cruciate ligament (ACL) graft rupture in patients who have undergone ACL reconstruction by comparing results in patients who experienced graft rupture and a matched control group. Methods: The study included 64 knees of 64 patients (58 men and 6 women), of mean age 31 years (range, 18‐60 years) who underwent revision ACL reconstruction for ACL graft rupture, as well as a control group without ACL graft rupture matched for age, sex, body mass index (BMI), and left or right side. The mean time to failure in study group was 48.5 months, and after revision surgeries, the mean follow‐up period was 37.7 months. The graft used for the primary surgery was autograft in 3 patients (4.7%) and allograft in 49 patients (76.6%). The type of graft could not be confirmed in the remaining 12 patients (18.7%). PTS was measured on plain radiographs and compared in the 2 groups. Results: Mean PTS was significantly higher in patients with (13.2° ± 2.5°; range, 8.5°‐18.2°) than without (10.9° ± 3.1°; range, 4.9°‐13.6°) rerupture ( P < .01). When mean PTS was compared in the 37 patients who underwent primary surgery by the same surgeon, it was significantly higher in patients with (13.5° ± 2.5°; range, 8.5°‐18.2°) than without (11.1° ± 2.9°; range, 5.1°‐13.6°) rerupture ( P < .01). PTS in patients with rerupture was not significantly associated with age, gender, BMI, and right or left side. The odds ratio of ACL graft rupture in knees with PTS ≥12° was 4.52 ( P < .001). Conclusions: This study showed that mean PTS was significantly greater in patients with than without noncontact ACL graft rerupture (13.2° vs 10.9°, P < .01). The failure of ACL reconstruction appears to be associated with increased PTS, with PTS ≥12° a risk factor for the failure of ACL reconstruction. Level of Evidence: Level III, retrospective comparative study.


  • Open Access

    Enhanced Reality Showing Long-Lasting Analgesia after Total Knee Arthroplasty: Prospective, Randomized Clinical Trial

    by Kyo-In Koo, Dae Kwon Park, Yoon Seok Youm, Sung Do Cho, Chang Ho Hwang

    To overcome the limitation of short-term efficacy of virtual reality (VR), an enhanced reality (ER) analgesia, (combination of the VR, real-time motion capture, mirror therapy [MT]) involving a high degree of patients’ presence or embodiment was explored. Patients, who underwent unilateral total knee arthroplasty (TKA), received ER analgesia. The duration was 5 times a week, for 2 weeks for one group and 5 times a week, for 1 week in the other. Visual Analogue Scale (VAS) at rest and during movement, active knee range of motion (ROM) for flexion and extension were measured repeatedly. After screening 157 patients, 60 were included. Pre-interventional evaluation was performed at 6.7 days and ER was initiated at 12.4 days after surgery. Evaluation was performed at 5, 12, 33 days after the initiation of ER. Analgesia in the 2 week therapy group was effective until the third evaluation (p = 0.000), whereas in the other group, it was effective only until the second evaluation (p = 0.010). Improvement in ROM in the 2 week group was also maintained until the third evaluation (p = 0.037, p = 0.009). It could lay the foundations for the development of safe and long-lasting analgesic tools.


  • Open Access

    Synovial fluid levels of TWEAK and matrix metalloproteinase 1 in patients with osteoarthritis, and associations with disease severity

    by Il-Yeong Hwang, Yoon-Seok Youm, Sung-Do Cho, Seung-Won Choi, Mun-Hee Bae, Seon-Jae Park, Han-Wook Kim

    Purpose: This study assessed the levels of soluble tumor necrosis factor–like weak inducer of apoptosis (TWEAK) and matrix metalloproteinase 1 (MMP-1) in the synovial fluid from osteoarthritic knees to determine their role as well as the relationship between these levels and the severity of osteoarthritis (OA). Methods: Synovial fluid was obtained from 44 knees of 40 patients. The Kellgren–Lawrence (KL) grade was measured using radiograph. The concentration of TWEAK and MMP-1 in the synovial fluid was assessed by enzyme-linked immunosorbent assay. The underlying inflammatory factors (erythrocyte sedimentation rate and C-reactive protein) were also measured. We analyzed the correlation between the factors measured. In addition, the samples were subdivided into three groups according to OA severity using the KL grade, and the differences in TWEAK and MMP-1 levels between groups were analyzed. Results: The TWEAK and MMP-1 levels in the synovial fluid showed a positive correlation with each other. The TWEAK and MMP-1 levels were compared between the three groups according to the KL grade, and the levels showed a significant difference. A post hoc test demonstrated that the group with advanced OA showed a lower concentration of both factors when compared to groups with early OA. Conclusion: The concentration of TWEAK and MMP-1 in the synovial fluid were relatively high in the early stage of OA, and the levels decreased as the OA progressed.


  • Preemptive Femoral Nerve Block Could Reduce the Rebound Pain After Periarticular Injection in Total Knee Arthroplasty

    by Yoon Seok Youm, Sung Do Cho, Hye Yong Cho, Chang Ho Hwang, Seung Hyun Jung, Kwang Ho Kim


  • Open Access

    Patterns and Influencing Factors of Medial Meniscus Tears in Varus Knee Osteoarthritis

    by Sung-Do Cho, Yoon-Seok Youm, Jong-Hyun Kim, Hye-Yong Cho, Kwang-Ho Kim

    Cho SD, et al. Knee Surg Relat Res. 2016 Jun;28(2):142-146. http://dx.doi.org/10.5792/ksrr.2016.28.2.142