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Featured researches published by Young Hak Roh.


American Journal of Sports Medicine | 2015

Comparison of the Cellular Composition and Cytokine-Release Kinetics of Various Platelet-Rich Plasma Preparations.

Joo Han Oh; Woo Kim; Kyoung Un Park; Young Hak Roh

Background: Variations in formulations used to prepare platelet-rich plasmas (PRPs) result in differences in the cellular composition and biomolecular characteristics. Purpose: To evaluate the cellular composition and the cytokine-release kinetics of PRP according to differences in the preparation protocols. Study Design: Controlled laboratory study. Methods: Five preparation procedures were performed for 14 healthy subjects, including 2 manual procedures (single-spin [SS] at 900g for 5 minutes; double-spin [DS] at 900g for 5 minutes and then 1500g for 15 minutes) and 3 methods with commercial kits (Arthrex ACP, Biomet GPS, and Prodizen Prosys). After evaluation of cellular composition, each preparation was divided into 4 aliquots and incubated for 1 hour, 24 hours, 72 hours, and 7 days for the assessment of cytokine release over time. The cytokine-release kinetics were evaluated by assessing platelet-derived growth factor (PDGF), transforming growth factor (TGF), vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), interleukin-1 (IL-1), and matrix metalloproteinase–9 (MMP-9) concentrations of each aliquot with bead-based sandwich immunoassay. Results: The DS PRP had a higher concentration of platelets and leukocytes than did the SS PRP. Every PRP preparation exhibited an increase in PDGF, TGF, VEGF, and FGF release when compared with whole blood samples. The FGF and TGF release occurred quickly and decreased over time, while the PDGF and VEGF release was constant and sustained over 7 days. The PDGF and VEGF concentrations were higher in the DS PRP than in the SS PRP, whereas the TGF and FGF concentrations were higher in the SS PRP than in the DS PRP. Biomet GPS had the highest VEGF and MMP-9 concentrations but the lowest TGF concentration. Arthrex ACP had the highest FGF concentration but the lowest PDGF concentration. Prodizen Prosys had the highest IL-1 concentration and higher PDGF concentration than Arthrex ACP. Conclusion: The DS method generally led to a higher concentration of platelet relative to the SS method. However, the cytokine content was not necessarily proportional to the cellular composition of the PRPs, as the greater content could be different between the SS or DS method depending on the type of cytokine. Clinical Relevance: Physicians should select proper PRP preparations after considering their biomolecular characteristics and patient indications.


Arthroscopy | 2013

Femoral tunnel position on conventional magnetic resonance imaging after anterior cruciate ligament reconstruction in young men: transtibial technique versus anteromedial portal technique.

Jung Ho Noh; Young Hak Roh; Bo Gyu Yang; Seung Rim Yi; Sung Yup Lee

PURPOSE The purpose of this study was to compare clinical outcomes after single-bundle anterior cruciate ligament (ACL) reconstruction with a free Achilles tendon allograft using either a transtibial or an anteromedial portal technique and then to quantify the difference in femoral tunnel position between these 2 approaches. This assessment was to be performed with a new method using conventional magnetic resonance imaging (MRI) with a digital imaging system. METHODS In this prospective randomized comparative study, 53 young male patients with ACL rupture underwent ACL reconstruction with the transtibial technique (group 1) or the anteromedial portal technique (group 2). We assessed clinical outcomes with the Lachman test, pivot shift test, International Knee Documentation Committee (IKDC) classification, Lysholm score, Tegner activity scale, and single leg hop (SLH) test. Radiologic assessments included the position of the femoral tunnel aperture and the posterior cruciate ligament (PCL) index on conventional MRI and the side-to-side difference (SSD) on stress radiographs. RESULTS Sixty-one participants had follow-up. The mean follow-up period was 30.2 months. At the last follow-up, there were no significant differences between the 2 groups in results from the Lachman test, pivot shift test, IKDC classification, Tegner activity scale, and SLH test. The Lysholm score and SSD results in group 2 were superior to those in group 1 (P < .001). The femoral tunnel aperture was positioned more posteriorly in group 2 than in group 1 (P < .001). Changes in the PCL index were greater in group 1 than in group 2 (P < .001). CONCLUSIONS The position of the femoral tunnel aperture created with the anteromedial portal technique was more posterior than that made with the transtibial technique. Knees reconstructed with the anteromedial portal technique were more stable in Telos testing, and were 3 points higher on the Lysholm score. However, there were no statistically significant differences in the Tegner activity scale or IKDC classification between the 2 groups. LEVEL OF EVIDENCE Therapeutic level I, randomized controlled clinical trial.


Bone and Joint Research | 2016

Cytokine-release kinetics of platelet-rich plasma according to various activation protocols

Young Hak Roh; W. Kim; K. U. Park

Objectives This study was conducted to evaluate the cytokine-release kinetics of platelet-rich plasma (PRP) according to different activation protocols. Methods Two manual preparation procedures (single-spin (SS) at 900 g for five minutes; double-spin (DS) at 900 g for five minutes and then 1500 g for 15 minutes) were performed for each of 14 healthy subjects. Both preparations were tested for platelet activation by one of three activation protocols: no activation, activation with calcium (Ca) only, or calcium with a low dose (50 IU per 1 ml PRP) of thrombin. Each preparation was divided into four aliquots and incubated for one hour, 24 hours, 72 hours, and seven days. The cytokine-release kinetics were evaluated by assessing PDGF, TGF, VEGF, FGF, IL-1, and MMP-9 concentrations with bead-based sandwich immunoassay. Results The concentration of cytokine released from PRP varied over time and was influenced by various activation protocols. Ca-only activation had a significant effect on the DS PRPs (where the VEGF, FGF, and IL-1 concentrations were sustained) while Ca/thrombin activation had effects on both SS and DS PRPs (where the PDGF and VEGF concentrations were sustained and the TGF and FGF concentrations were short). The IL-1 content showed a significant increase with Ca-only or Ca/thrombin activation while these activations did not increase the MMP-9 concentration. Conclusion The SS and DS methods differed in their effect on cytokine release, and this effect varied among the cytokines analysed. In addition, low dose of thrombin/calcium activation increased the overall cytokine release of the PRP preparations over seven days, relative to that with a calcium-only supplement or non-activation. Cite this article: Professor J. H. Oh. Cytokine-release kinetics of platelet-rich plasma according to various activation protocols. Bone Joint Res 2016;5:37–45. DOI: 10.1302/2046-3758.52.2000540


Journal of Bone and Joint Surgery, American Volume | 2012

Outcomes of Operative Treatment of Unstable Ankle Fractures: A Comparison of Metallic and Biodegradable Implants

Jung Ho Noh; Young Hak Roh; Bo Gyu Yang; Seong Wan Kim; Jun Suk Lee; Moo Kyung Oh

BACKGROUND Biodegradable implants for internal fixation of ankle fractures may overcome some disadvantages of metallic implants, such as imaging interference and the potential need for additional surgery to remove the implants. The purpose of this study was to evaluate the outcomes after fixation of ankle fractures with biodegradable implants compared with metallic implants. METHODS In this prospectively randomized study, 109 subjects with an ankle fracture underwent surgery with metallic (Group I) or biodegradable implants (Group II). Radiographic results were assessed by the criteria of the Klossner classification system and time to bone union. Clinical results were assessed with use of the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scale, Short Musculoskeletal Function Assessment (SMFA) dysfunction index, and the SMFA bother index at three, six, and twelve months after surgery. RESULTS One hundred and two subjects completed the study. At a mean of 19.7 months, there were no differences in reduction quality between the groups. The mean operative time was 30.2 minutes in Group I and 56.4 minutes in Group II (p < 0.001). The mean time to bone union was 15.8 weeks in Group I and 17.6 weeks in Group II (p = 0.002). The mean AOFAS score was 87.5 points in Group I and 84.3 points in Group II at twelve months after surgery (p = 0.004). The mean SMFA dysfunction index was 8.7 points in Group I and 10.5 points in Group II at twelve months after surgery (p = 0.060). The mean SMFA bother index averaged 3.3 points in Group I and 4.6 points in Group II at twelve months after surgery (p = 0.052). No difference existed between the groups with regard to clinical outcomes for the subjects with an isolated lateral malleolar fracture. CONCLUSIONS The outcomes after fixation of bimalleolar ankle fractures with biodegradable implants were inferior to those after fixation with metallic implants in terms of the score on the AOFAS scale and time to bone union. However, the difference in the final AOFAS score between the groups may not be clinically important. The outcomes associated with the use of biodegradable implants for the fixation of isolated lateral malleolar fractures were comparable with those for metallic implants.


Archives of Orthopaedic and Trauma Surgery | 2014

Reliability and validity of carpal alignment measurements in evaluating deformities of scaphoid fractures

Young Hak Roh; Jung Ho Noh; Beom Koo Lee; Jong Ryoon Baek; Joo Han Oh; Hyun Sik Gong; Goo Hyun Baek

PurposeSeveral radiographic carpal alignment indices are used to evaluate the deformities of scaphoid fractures. The purpose of this study was to determine the reliabilities and validities of radiographic carpal alignment indices commonly used to evaluate deformities of scaphoid fractures.MethodsThirty-six patients with a scaphoid fracture were evaluated. Five carpal alignment indices were assessed on lateral plain radiographs, namely, scapholunate angle, radioscaphoid angle, radiolunate angle, radiocapitate angle, and capitolunate angle. Three examiners measured these radiographic indices at two sessions, and intraobserver and interobserver reliabilities were determined and expressed as intraclass correlation coefficients. Discriminant validities of radiographic carpal alignment indicies between injured and uninjured wrists were evaluated. For convergent validity testing, the correlation between the radiographic carpal alignment indices and intrascaphoid angles (ISAs) or height-to-length (HL) ratios on CT longitudinal scans was assessed. Further, carpal alignment indices after surgical reconstruction were compared to the Mayo wrist score.ResultsScapholunate and radiolunate angles had the highest reliabilities, and radiocapitate angle had the lowest. Radiolunate angle had the highest discriminant validity followed by scapholunate, and capitolunate angles. In convergent validity testing, scapholunate angles and radiolunate angles correlated with ISA angles, and radiolunate and capitolunate angles correlated with HL ratios. Only the radiolunate angles correlated with the Mayo wrist scores.ConclusionsAmong radiographic carpal alignment measures, radiolunate angle is the most reliable and valid carpal alignment index for evaluating deformities of scaphoid fractures. Scapholunate and capitolunate angles could be used as an alternative, but have less validity.


Arthroscopy | 2011

Anterior cruciate ligament reconstruction using 4-strand hamstring autograft: conventional single-bundle technique versus oval-footprint technique.

Jung Ho Noh; Bo Gyu Yang; Young Hak Roh; Seong Wan Kim; Woo Kim

PURPOSE The purpose of this study was to compare short-term results of conventional anterior cruciate ligament (ACL) reconstruction with oval-footprint (modified) single-tunnel ACL reconstruction with 4-strand hamstring autograft. METHODS A prospective comparative study was performed in 74 consecutive subjects who underwent ACL reconstruction with the conventional technique (group I, 40 cases) or the modified technique (group II, 34 cases), in which the entrances of the femoral and tibial tunnels were more elongated, by use of 4-strand hamstring tendon. The Lachman test, pivot-shift test, range of motion, International Knee Documentation Committee classification, Lysholm score, and side-to-side differences were evaluated preoperatively and at the last follow-up. The Tegner activity scale was evaluated before injury and at the last follow-up. RESULTS There were 38 patients in group I and 32 in group II who were followed up for at least 2 years (mean follow-up, 32.4 months). At the last follow-up, Lachman test results were negative in 34 in group I and 30 in group II (P = .624) and the pivot-shift test was negative in 32 in group I and 30 in group II (P = .397). Mean range of motion of the injured knee was 142.2° in group I and 141.9° in group II (P = .771). The International Knee Documentation Committee classification was A or B in 37 in group I and 31 in group II (P = .872). The median Lysholm score was 94 in group I and 96 in group II (P = .048). The mean side-to-side difference averaged 2.08 mm in group I and 2.07 mm in group II (P = .943). The median score on the Tegner activity scale was 6 in group I and 6 in group II (P = .968). CONCLUSIONS The Lysholm score in the modified-technique group at the last follow-up was better than that in the conventional-technique group in terms of statistical significance, but this may not be clinically significant. LEVEL OF EVIDENCE Level II, prospective comparative study.


Annals of Diagnostic Pathology | 2013

Nonossifying fibroma developed in metaphysis and epiphysis—a case report

Jung Ho Noh; Kyung Nam Ryu; Ji Yoon Bae; Young Hak Roh; In Seok Choi

Nonossifying fibroma is developed in childhood and adolescence and is usually asymptomatic. It is typically arises in the metaphysis of long bone and migrates toward the diaphysis with growth. We present a very rare case of nonossifying fibroma involving metaphysis and epiphysis of the distal femur in a 20-year-old man. Nonossifying fibroma is a benign fibroblastic lesion, which is also termed benign cortical defect and fibroxanthoma. A nonossifying fibroma rarely causes problems and does not interfere with healing or growth. The lesions are usually asymptomatic. With growth and remodeling of the bone, the lesion typically disappears and is replaced with normal bone. However, the lesion may weaken the involved bone, causing fracture. The lesion typically arises in the metaphysis of long bones and may migrate toward the diaphysis with growth. There have never been reports of nonossifying fibroma involving epiphysis that we know of. We report a very rare case of nonossifying fibroma involving metaphysis and epiphysis in a young adult. Written, informed consent was obtained from the patient to publish this case report, including the images.


Arthroscopy | 2012

Hybrid Tibial Fixation for Anterior Cruciate Ligament Reconstruction With Achilles Tendon Allograft

Jung Ho Noh; Bo Gyu Yang; Seung Rim Yi; Young Hak Roh; Jun Suk Lee

PURPOSE To compare clinical outcomes of tibial fixation between a biodegradable interference screw only and a biodegradable interference screw supplemented by a post-tie using a washer screw in single-bundle anterior cruciate ligament (ACL) reconstruction with 2-strand free tendon Achilles allograft in active young men. METHODS A prospective study was performed in 80 subjects who underwent single-bundle ACL reconstruction. A 2-strand free tendon Achilles allograft fixed with an EndoButton (Smith & Nephew, Andover, MA) in the femoral tunnel and with a Bio-Interference screw (Arthrex, Naples, FL) in the tibial tunnel was used in group I. Supplementary fixation was performed with a post-tie using a washer screw in group II. The Lachman test, pivot-shift test, International Knee Documentation Committee classification, Lysholm score, range of knee motion, and side-to-side difference were evaluated preoperatively and at the last follow-up. The Tegner activity scale was evaluated before injury and at the last follow-up. The 1-leg hop test was assessed at the last follow-up. RESULTS Of the patients, 36 in group I and 35 in group II could be followed up for at least 2 years. At the last follow-up, 7 patients in group I and 1 in group II showed a 2+ or 3+ on the Lachman test (P = .027). The mean side-to-side difference was 2.9 ± 2.3 mm in group I and 1.4 ± 1.6 mm in group II at the last follow-up (P = .002). The other clinical outcomes were not significantly different between the 2 groups. CONCLUSIONS Supplementary tibial fixation with a post-tie in ACL reconstruction using 2-strand free tendon Achilles allograft was more effective than a biodegradable interference screw only in restoration of the anterior stability of the tibia. LEVEL OF EVIDENCE Level II, randomized controlled trial.


Arthroscopy techniques | 2014

Re-Tensioning Technique to Cover the Graft With Remnant in Anterior Cruciate Ligament Reconstruction

Jung Ho Noh; Kyoung Ho Yoon; Sang Jun Song; Young Hak Roh

A number of remnant-preserving techniques to restore proprioceptive function in anterior cruciate ligament reconstruction have been described. However, they might not cover the significant amount of the graft with the synovium of the remnant in many cases. We introduce a simple technique that can cover nearly the entire graft with the synovium by re-tensioning the remnant, which might enhance synovialization of the graft and restoration of proprioception.


Journal of Hand Surgery (European Volume) | 2017

Effects of metabolic syndrome on the functional outcomes of corticosteroid injection for De Quervain tenosynovitis

Young Hak Roh; Jung Ho Noh; Hyun Sik Gong; Goo Hyun Baek

Metabolic syndrome is a constellation of medical conditions that arise from insulin resistance and abnormal adipose deposition and function. In patients with metabolic syndrome and De Quervain tenosynovitis this might affect the outcome of treatment by local corticosteroid injection. A total of 64 consecutive patients with De Quervain tenosynovitis and metabolic syndrome treated with corticosteroid injection were age- and sex-matched with 64 control patients without metabolic syndrome. The response to treatment, including visual analogue scale score for pain, objective findings consistent with De Quervain tenosynovitis (tenderness at first dorsal compartment, Finkelstein test result), and Disability of the Arm, Shoulder, and Hand score were assessed at 6, 12, and 24 weeks follow-up. Treatment failure was defined as persistence of symptoms or surgical intervention. Prior to treatment, patients with metabolic syndrome had mean initial pain visual analogue scale and Disability of the Arm, Shoulder, and Hand scores similar to those in the control group. The proportion of treatment failure in the metabolic syndrome group (43%) was significantly higher than that in the control group (20%) at 6 months follow-up. The pain visual analogue scale scores in the metabolic syndrome group were higher than the scores in the control group at the 12- and 24-week follow-ups. The Disability of the Arm, Shoulder, and Hand scores of the metabolic syndrome group were higher (more severe symptoms) than those of the control group at the 12- and 24-week follow-ups. Although considerable improvements in symptom severity and hand function will likely occur in patients with metabolic syndrome, corticosteroid injection for De Quervain tenosynovitis is not as effective in these patients compared with age- and sex-matched controls in terms of functional outcomes and treatment failure. Level of evidence: III

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Goo Hyun Baek

Seoul National University

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Hyun Sik Gong

Seoul National University Bundang Hospital

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Joo Han Oh

Seoul National University Bundang Hospital

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Woo Kim

Seoul National University

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Young Ho Lee

Seoul National University Hospital

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