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Dive into the research topics where Seung Hwan Han is active.

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Featured researches published by Seung Hwan Han.


Foot & Ankle International | 2007

Chronic Tibiofibular Syndesmosis Injury: The Diagnostic Efficiency of Magnetic Resonance Imaging and Comparative Analysis of Operative Treatment

Seung Hwan Han; Jin Woo Lee; Sungjun Kim; Jin-Suck Suh; Yoon Rak Choi

Background: The purpose of this study was to determine the sensitivity and specificity of MRI in chronic syndesmosis injury by comparing the arthroscopic findings with MRI findings and to suggest therapeutic guidelines of syndesmotic fixation. Methods: Between January, 2003, and January, 2004, 20 patients were diagnosed with chronic syndesmosis injury according to syndesmosis widening (>2 mm) on arthroscopic examination. The average age of the patients was 32 years. The minimum followup was 22 (22 to 30) months. MRI was obtained in all patients. For evaluating the therapeutic role of syndesmotic fixation, we separated the patients into two groups (with and without transfixation) and compared preoperative and postoperative American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores and patient satisfaction. Results: The sensitivity, specificity, and accuracy of MRI were 90.0%, 94.8%, and 93.4%, respectively. In group I with syndesmotic fixation, the AOFAS ankle-hindfoot scale improved from 52 to 87, and in group II without syndesmotic fixation the score improved from 63 to 90 at last followup, which showed no statistically significant difference (p = 0.6453). Also, patient satisfaction showed no difference between the two groups. Conclusions: MRI showed high sensitivity, specificity, and accuracy under the criteria we proposed, and we recommend it as the main diagnostic tool for diagnosing a chronic syndesmosis injury. These findings might suggest that pain is mainly caused by hypertrophy and impingement of the soft tissue in the distal tibiofibular joint. Arthroscopic debridement alone can be recommended if the distal tibiofibular chronic syndesmosis injury is not combined with medial ankle instability and lateral displacement of the talus.


Wound Repair and Regeneration | 2016

Hyaluronic acid dressing (Healoderm) in the treatment of diabetic foot ulcer: A prospective, randomized, placebo-controlled, single-center study

Moses Lee; Seung Hwan Han; Woo Jin Choi; Kwang Ho Chung; Jin Woo Lee

Fast and complete healing of a diabetic foot ulcer (DFU) is challenging due to the hostile wound healing environment of the diabetic patients. As a part of a multimodal treatment approach, advanced dressing material using hyaluronic acid (HA) has been found to be effective. However, previous studies have used HA with additional biologics, which interferes in determining the true clinical effect of HA in DFU. To examine the sole effectiveness of HA in DFU treatment, a prospective, randomized, placebo‐controlled, single‐center study was conducted using an HA dressing without additional substances. Thus, 34 patients who met the inclusion criteria were randomized into two groups (the study group: HA dressing material; the control group: conventional dressing material). During the 12‐week study period, complete ulcer healing rate was evaluated as a primary endpoint. Additionally, healing velocity and the mean duration for achieving a 50% ulcer size reduction was compared between the two groups as a secondary endpoint. At the end of the study, the study group presented a significantly higher complete healing rate as compared to that in the control group [84.6% (11/13), 41.6% (5/12), respectively, P = 0.041]. Additionally, faster ulcer healing velocity and shorter mean duration for achieving a 50% ulcer size reduction were observed in the study group (P = 0.022 and 0.004, respectively). The Kaplan‐Meier survival analysis for the median time for 50% ulcer healing rate also showed a significantly shorter duration in the study group (21 days vs. 39 days, P = 0.0127). Finally, there were no adverse events related to the dressing materials used in the study. As a major component of the extracellular matrix, this study supports the safety and efficacy of a pure HA dressing without additional substances in treating DFU.


Metabolism-clinical and Experimental | 2017

Obesity is more closely related with hepatic steatosis and fibrosis measured by transient elastography than metabolic health status

Ji Hye Huh; Kwang Joon Kim; Seung Up Kim; Seung Hwan Han; Kwang Hyub Han; Bong Soo Cha; Choon Hee Chung; Byung Wan Lee

OBJECTIVE The pathogenesis of non-alcoholic fatty liver disease (NAFLD) involves multiple concomitant events induced by obesity and metabolic health condition. This study aimed to assess the risk of NAFLD according to metabolic health and obesity status using transient elastography (TE). MATERIALS AND METHODS A total of 2198 asymptomatic adults without chronic liver disease and who underwent a medical health check-up were recruited. Subjects were categorized into four groups according to metabolic health and obesity statuses: metabolically healthy non-obese (MHNO); metabolically unhealthy non-obese (MUNO); metabolically healthy obese (MHO); and metabolically unhealthy obese (MUO). Hepatic steatosis was defined as controlled attenuation parameter (CAP)≥238dB/m, and significant liver fibrosis was defined as liver stiffness measurement (LSM) >7.0kPa, as defined by TE. RESULTS Compared with MHNO group, the odds ratios (ORs) [95% confidence interval (CI)] for hepatic steatosis were 2.94 [2.32-3.71], 4.62 [3.52-6.07], and 12.02 [9.08-15.92] in the MUNO, MHO, and MUO groups, respectively (P<0.001) in crude model. Regarding liver fibrosis, there was no significant difference in the ORs in MUNO group (ORs: 0.95 [95% CI, 0.33-2.78], P value = 0.929), whereas there was a significant increase in the ORs in MHO group compared with MHNO group (ORs: 4.32 [95% CI, 1.73-10.76], P=0.002) in the fully adjusted model. CONCLUSION Our results show that MHO was associated with both liver steatosis and fibrosis assessed by transient elastography. Our results suggest that a healthy metabolic profile does not protect obese adults from hepatic steatosis or fibrosis, indicating that obesity itself might contribute to liver fibrosis.


Yonsei Medical Journal | 2015

First Metatarsal Proximal Opening Wedge Osteotomy for Correction of Hallux Valgus Deformity: Comparison of Straight versus Oblique Osteotomy

Seung Hwan Han; Eui Hyun Park; Joon Jo; Yong Gon Koh; Jin Woo Lee; Woo Jin Choi; Yong Sang Kim

Purpose The aim of this study was to compare clinical and radiographic outcomes of proximal opening wedge osteotomy using a straight versus oblique osteotomy. Materials and Methods We retrospectively reviewed 104 consecutive first metatarsal proximal opening wedge osteotomies performed in 95 patients with hallux valgus deformity. Twenty-six feet were treated using straight metatarsal osteotomy (group A), whereas 78 feet were treated using oblique metatarsal osteotomy (group B). The hallux valgus angle (HVA), intermetatarsal angle (IMA), distal metatarsal articular angle, and distance from the first to the second metatarsal (distance) were measured for radiographic evaluation, whereas the American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score was used for clinical evaluation. Results Significant corrections in the HVA, IMA, and distance from the first to the second metatarsal were obtained in both groups at the last follow-up (p<0.001). There was no difference in the mean IMA correction between the 2 groups (6.1±2.7° in group A and 6.0±2.1° in group B). However, a greater correction in the HVA and distance from the first to the second metatarsal were found in group B (HVA, 13.2±8.2°; distance, 25.1±0.2 mm) compared to group A (HVA, 20.9±7.7°; distance, 28.1±0.3 mm; p<0.001). AOFAS scores were improved in both groups. However, group B demonstrated a greater improvement relative to group A (p=0.005). Conclusion Compared with a straight first metatarsal osteotomy, an oblique first metatarsal osteotomy yielded better clinical and radiological outcomes.


Foot & Ankle Orthopaedics | 2018

Arthroscopic Bone Marrow Stimulation in the Treatment of Osteochondral Lesions of the Talus: Outcomes Over Ten Years of Follow-up

Kwang Hwan Park; JaeHan Park; Jai Bum Kwon; Seung Hwan Han; Jin Woo Lee

Category: Arthroscopy Introduction/Purpose: Arthroscopic bone marrow stimulation for osteochondral lesions of the talus (OLT) has presented promising clinical outcomes in recent studies. However, there were few studies which had investigated long-term clinical outcomes. The purpose of this study is to evaluate the long-term outcomes of arthroscopic bone marrow stimulation for osteochondral lesion of the talus and to identify prognostic factors that affect the outcome. Methods: Between January 2001 and December 2007, 159 patients (172 ankles) with OLT underwent arthroscopic bone marrow stimulation as a primary surgery. Clinical outcomes were assessed using visual analog scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) scores, Foot and Ankle Outcome Score (FAOS) and re-operation rate. Factors associated with re-operation were evaluated using bivariate analysis. Kaplan-Meier plot showed survival outcomes of OLT in long-term follow-up. Results: The mean follow-up time was 12.7 years (range 10.1-16.8) and the mean size of the lesion was 105.4 mm2 (range 19.8- 322.8). The mean VAS improved from 7.21 ± 1.71 to 1.76 ± 1.60. The mean preoperative AOFAS score was 57.98 ±14.43 and the mean postoperative AOFAS was 82.91 ± 11.58. FAOS at the time of final follow-up was comparable with those of previous literatures which showed outcomes of surgical treatments of OLT in short- and mid-term follow-up. Re-operation rate was 6.40% (11 patients with 12 revision surgery) including seven cases of re-arthroscopic bone marrow stimulation, and five cases of OAT. According to bivariate analysis, significant factor associated with re-operation was large sized OLT in preoperative MRI measurement. Conclusion: Arthroscopic bone marrow stimulation for osteochondral lesion of the talus has made satisfactory clinical outcomes through long-term follow-up over 10 years.


Foot & Ankle Orthopaedics | 2018

Long-term evaluation of Primary Osteochondral Autograft Transfer System (OATS) for large cystic type osteochondral lesion of talus

Dong Woo Shim; Yeokgu Hwang; Kwang Hwan Park; Jin Woo Lee; Seung Hwan Han

Category: Ankle Introduction/Purpose: Osteochondral lesions of talus (OLTs) are often treated primarily by fragment excision, abrasion, drilling, or microfracture. However, OLT accompanying with large cyst has been challenged to yield good outcome nevertheless of many surgical options. Recent study showed significant high failure rate of arthroscopic marrow stimulation treatment larger than 150mm2. The current study is to investigate the outcome of the primary osteochondral autograft transfer system (OATS) for large cystic type OLT (>150mm2). Methods: This retrospective analysis included 19 talus (19 patients) with diagnosed large cystic type OLT (>150mm2) who received primary OATS between September 2009 and March 2013. Defect size area was measured on magnetic resonance imaging (MRI) by the ellipse formula from coronal and sagittal length. The patients completed the visual analog scale (VAS) and the American Orthopaedic Foot & Ankle Society (AOFAS) score preoperatively and at follow-up. Plain radiographs were used to show the improvement of radiolucency postoperatively. Results: The mean follow up period was 83.9 months (57 – 99) and the average defect size area was 169.4 mm2 (151.3 – 392.6). The Mean VAS score decreased from 6.95 preoperatively to 2.6 postoperatively. Average AOFAS score improved from 66.8 preoperatively to 88.7 postoperatively. Eighty percent of patients rated their result excellent or good. The radiolucent area of the cysts disappeared on the plain radiographs in all cases. Conclusion: Long-term clinical results of primary OATS in large cystic type OLT showed good outcomes and patients could significantly benefit from this surgery.


Diabetes Research and Clinical Practice | 2018

Topical epidermal growth factor spray for the treatment of chronic diabetic foot ulcers: A phase III multicenter, double-blind, randomized, placebo-controlled trial

Kwang Hwan Park; Seung Hwan Han; Joon Pio Hong; Seung-Kyu Han; Doo-Hyung Lee; Bom Soo Kim; Jae Hoon Ahn; Jin Woo Lee

AIMS This study was conducted to evaluate the efficacy and safety of a novel spray-applied growth factor therapy containing recombinant human epidermal growth factor (rhEGF) for the treatment of chronic diabetic foot ulcers (DFU). METHODS This study was a phase III double-blind, randomized, placebo-controlled trial. 167 adult patients at six medical centers were randomized to receive routine wound care plus either topical spray treatment with 0.005% rhEGF (n = 82) or an equivalent volume of saline spray (n = 85) twice a day until ulcer healing or for up to 12 weeks. RESULTS Demographics, medical status, and wound characteristics were comparable between rhEGF and placebo groups. More patients in the rhEGF group significantly had complete wound healing compared to placebo (73.2% versus 50.6%, respectively; P = .001). Wound healing velocity was faster in the rhEGF group (P = .029) regardless of HbA1c levels. The rhEGF group had a shorter median time to 50% ulcer size reduction (21 versus 35 days; hazard ratio = 3.13, P < .001) and shorter time to complete ulcer healing (56 versus 84 days; hazard ratio = 2.13, P < .001). CONCLUSIONS This study confirms that application of spray-applied rhEGF in DFU patients results in faster healing velocity and higher complete healing rate regardless of HbA1c levels.


American Journal of Sports Medicine | 2018

Primary Versus Secondary Osteochondral Autograft Transplantation for the Treatment of Large Osteochondral Lesions of the Talus

Kwang Hwan Park; Yeokgu Hwang; Seung Hwan Han; Yoo Jung Park; Dong Woo Shim; Woo Jin Choi; Jin Woo Lee

Background: Recent studies have reported promising clinical results after osteochondral autograft transplantation (OAT) for the treatment of large osteochondral lesions of the talus (OLT). However, no study has yet compared clinical outcomes between primary and secondary OAT for large OLT. Purpose: To compare clinical outcomes among patients with large OLT who receive primary OAT versus those who receive secondary OAT after failure of marrow stimulation and to identify factors associated with clinical failure. Study Design: Cohort study; Level of evidence, 3. Methods: From 2005 to 2014, 46 patients with large OLT (≥150 mm2) underwent OAT: 18 underwent OAT as initial surgical management (primary OAT group), and 28 patients underwent secondary OAT after failure of previous arthroscopic marrow stimulation (secondary OAT group). In both groups, OAT procedures included arthroscopic inspection and debridement of concomitant soft tissue injuries. Clinical outcomes were assessed using pain visual analog scale (VAS), the Roles and Maudsley score, Foot and Ankle Outcome Scores (FAOS), and revisional surgery rates. Factors associated with clinical failures were evaluated using bivariate and logistic regression analyses. Survival outcomes were compared using Kaplan-Meier analysis. Results: Mean follow-up time was 6 years (range, 2-10.8 years). Mean lesion size was 194.9 mm2 (range, 151.7-296.3 mm2). There were no significant differences between groups in patient demographics and preoperative findings. Postoperative pain VAS, Roles and Maudsley score, FAOS, and revisional surgery rates were not significantly different at last follow-up. Prior marrow stimulation was not significantly associated with clinical failure on bivariate analysis. Lesion size greater than 225 mm2 on preoperative magnetic resonance imaging was significantly associated with clinical failure. Survival probabilities from Kaplan-Meier plots were not significantly different between the primary and secondary OAT groups (P = .947). Conclusion: Clinical outcomes of patients with large OLT treated with secondary OAT after failed marrow stimulation were found to be comparable with those who were treated with primary OAT. These results may be helpful to orthopaedic surgeons deciding appropriate surgical options for patients with large OLT.


Aging and Disease | 2018

Enhancement of Mesenchymal Stem Cell-Driven Bone Regeneration by Resveratrol-Mediated SOX2 Regulation

Yoorim Choi; Dong Suk Yoon; Kyoung-Mi Lee; Seong Mi Choi; Myon-Hee Lee; Kwang Hwan Park; Seung Hwan Han; Jin Woo Lee

Mesenchymal stem cells (MSCs) are an attractive cell source for regenerative medicine. However, MSCs age rapidly during long-term ex vivo culture and lose their therapeutic potential before they reach effective cell doses (ECD) for cell therapy. Thus, a prerequisite for effective MSC therapy is the development of cell culture methods to preserve the therapeutic potential during long-term ex vivo cultivation. Resveratrol (RSV) has been highlighted as a therapeutic candidate for bone disease. Although RSV treatment has beneficial effects on bone-forming cells, in vivo studies are lacking. The current study showed that long-term (6 weeks from primary culture date)-cultured MSCs with RSV induction retained their proliferative and differentiation potential despite reaching ECD. The mechanism of RSV action depends entirely on the SIRT1-SOX2 axis in MSC culture. In a rat calvarial defect model, RSV induction significantly improved bone regeneration after MSC transplantation. This study demonstrated an example of efficient MSC therapy for treating bone defects by providing a new strategy using the plant polyphenol RSV.


Acta Orthopaedica | 2018

What is the best treatment for displaced Salter-Harris II physeal fractures of the distal tibia?

Hoon Park; Dong Hoon Lee; Seung Hwan Han; Sungmin Kim; Hyunwoo Kim

Background and purpose — The optimal treatment of displaced Salter–Harris (SH) II fractures of the distal tibia is controversial. We compared the outcomes of operative and nonoperative treatment of SH II distal tibial fractures with residual gap of >3 mm. Factors that may be associated with the incidence of premature physeal closure (PPC) were analyzed. Patients and methods — We retrospectively reviewed 95 patients who were treated for SH II distal tibial fractures with residual gap of >3 mm after closed reduction. Patients were assigned to 1 of 2 groups: Group 1 included 25 patients with nonoperative treatment, irrespective of size of residual gap (patients treated primarily at other hospitals). Group 2 included 70 patients with operative treatment. All patients were followed for ≥ 12 months after surgery, with a mean follow-up time of 21 months. Logistic regression analyses were performed to identify risk factors for the occurrence of PPC. Results — The incidence of PPC in patients who received nonoperative treatment was 13/52, whereas PPC incidence in patients who received operative treatment was 24/70 (p = 0.1). Multivariable logistic regression analysis determined that significant risk factors for the occurrence of PPC were age at injury, and injury mechanism. The method of treatment, sex, presence of fibular fracture, residual displacement after closed reduction, and implant type were not predictive factors for the occurrence of PPC. Interpretation — Operative treatment for displaced SH II distal tibial fractures did not seem to reduce the incidence of PPC compared with nonoperative treatment. We cannot exclude that surgery may be of value in younger children with pronation–abduction or pronation–external rotation injuries.

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