Researcher:
Korkmaz, Murat

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Doctor

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Murat

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Korkmaz

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Korkmaz, Murat

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Now showing 1 - 7 of 7
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    Publication
    Influence of distal fusion level on sagittal spinopelvic and spinal parameters in the surgical management of adolescent idiopathic scoliosis
    (Korean Soc Spine Surgery, 2018) Akgul, Turgut; Sariyilmaz, Kerim; Ozkunt, Okan; Kaya, Ozcan; Dikici, Fatih; N/A; Korkmaz, Murat; Doctor; Koç University Hospital; 168011
    Study Design: trospective analysis of adolescent idiopathic scoliosis. Purposep: s study aimed to investigate the influence of distinct distal fusion levels on spinopelvic parameters in patients with adolescent idiopathic scoliosis (AIS) who underwent posterior instrumentation and fusion surgery. Overview of Literature: e distal fusion level selection in treatment of AIS is the one of milestone to effect on surgical outcome. Most of the paper focused on the coronal deformity correction and balance. The literature have lack of knowledge about spinopelvic changing after surgical treatment and the relation with distal fusion level. We evaluate the spinopelvic and pelvic parameter alteration after fusion surgery in treatment of AIS. Methods: total of 100 patients with AIS (88 females and 12 males) were retrospectively reviewed. Patients were assigned into the following three groups according to the distal fusion level: lumbar 2 (L2), lumbar 3 (L3), and lumbar 4 (L4). Using a lateral plane radiograph of the whole spine, spinopelvic angular parameters such as thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT) were radiologically assessed. Results: e mean age was 15+/-2.4 years, and the mean follow-up period was 24.27+/-11.69 months. Regarding the lowest instrumented vertebra, patients were categorized as follows: 30 patients in L2 (group 1), 40 patients in L3 (group 2), and 30 patients in L4 (group 3). TK decreased from 36.60+/-13.30 degrees preoperatively to 26.00+/-7.3 degrees postoperatively in each group (p=0.001). LL decreased from 52.8+/-9.4 degrees preoperatively to 44.30+/-7.50 degrees postoperatively (p=0.001). Although PI showed no difference preoperatively among the groups, it was statistically higher postoperatively in group 3 than in the other groups (p<0.05). In addition, in group 2, PI decreased from 50.60+/-8.74 degrees preoperatively to 48.00+/-6.84 degrees postoperatively (p=0.027). SS decreased from 35.20+/-6.40 degrees preoperatively to 33.40+/-5.80 degrees postoperatively (p=0.08, p>0.05). However, mean SS was significantly higher in group 3 (p=0.042, p<0.05). PT decreased from 15.50+/-7.90 degrees preoperatively to 15.2+/-7.10 degrees postoperatively. The positive relationship (28.5%) between LL and PI measurements was statistically significant (r=0.285; p=0.004, p<0.01). Furthermore, the positive relationship (36.5%) between LL and SS measurements was statistically significant (r=0.365; p=0.001, p<0.01). Conclusions: en the distal instrumentation level in AIS surgery is below L3, a significant change in PT and SS (pelvic parameters) is anticipated
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    Publication
    Conservative versus operative treatment of stable thoracolumbar burst fractures in neurologically intact patients is there any difference regarding the clinical and radiographic outcomes?
    (Lippincott Williams and Wilkins (LWW), 2020) Pehlivanoğlu, Tuna; Akgül, Turgut; Bayram, Serkan; Meriç, Emre; Özdemir, Mustafa; Şar, Cüneyt; N/A; Korkmaz, Murat; Doctor; Koç University Hospital; 168011
    Study Design. Nonrandomized, retrospective, comparative, and single-center trial. Objective. The aim of this study is to compare the long-term clinical and radiographic results of thoracolumbar burst fractures in neurologically intact patients, treated surgically or nonsurgically with the aim to optimize their management. Summary of Background Data. There is an ongoing controversy regarding the treatment of thoracolumbar burst fractures (TLBF) (A3, A4) in neurologically intact patients. Surgical treatment as well as conservative treatment methods are advised to this specific group of patients, while contrasting results exist in the literature. Methods. Forty-five neurologically intact patients with TLBF (A3 or A4) (2010-2016) were included. Twenty-one patients with a mean age of 34.3 and a mean follow-up period of 63.1 months were treated surgically with short segment posterior fixation (group 1), while 24 patients with a mean age of 45.7 and a mean follow-up period of 67.1 months were treated conservatively (group 2) with thoracolumbosacral orthesis. Results. At the final follow-up groups 1 and 2 had an average segmental kyphosis of 4.09 degrees/11.65 degrees (P = 0.027), an average loss of kyphosis of 2.04 degrees/4.03 degrees (P = 0.038), an average loss of anterior/posterior vertebral body height of %12.89/%2.84/%17.94/%7.62 (P = 0.027/ P = 0.03), a median JOA score of (16.6/16.75) (P = 0.198), a median ODI score of (11.7/12.1) (P = 0.25), a median VAS score of (1.9/2.3) (P = 0.3), SF-36 PCS of (56.74/56.67) (P = 0.25), SF-36 MCS of (55.47/55.5) (P = 0.3), mean durations of hospital stay of 9-11 days (P = 0.3), respectively. Conclusion. While there is an ongoing controversy regarding the management of stable thoracolumbar burst fractures in neurologically intact patients in the literature, this study concluded that surgical management of stable thoracolumbar burst fractures in neurologically intact patients provided better radiolographic outcomes, despite the result, that the difference between surgically and nonsurgically treated patients in terms of clinical outcome parameters and quality of life was not statistically significant.
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    Publication
    Selection of distal fusion level in terms of distal junctional kyphosis in Scheuermann kyphosis. A comparison of 3 methods
    (Turkish Assoc Orthopaedics Traumatology, 2018) Dikici, Fatih; Akgül, Turgut; Sarıyılmaz, Kerim; Özkunt, Okan; Sar, Cuneyt; Domaniç, Ünsal; N/A; Korkmaz, Murat; Doctor; Koç University Hospital; 168011
    Objective: The aim of this study was to investigate the effect of distal fusion level selection on the distal junctional kyphosis (DJK) in Scheuermann kyphosis (SK) patients who underwent posterior fusion. Methods: Thirty-nine SK patients who underwent posterior fusion with a minimum follow-up of 3 years were retrospectively evaluated. According to the distal fusion level, patients were divided into 3 groups. Group S; lowest instrumented vertebra (LIV) was the sagittal stable vertebra (SSV), Group F; LIV was the first lordotic vertebra (FLV) and, Group L; LIV was the lower end vertebra (LEV). DJK was evaluated according to distal level selection. Results: Thoracic kyphosis (TK) decreased from 73.3 degrees (SD +/- 7.9 degrees) to 39 degrees (SD +/- 8.7 degrees) postoperatively, with a mean correction rate of 46% (SD +/- 13) (p < 0.0001). In 11 patients, FLV and SSV was the same vertebra. In remaining 28 patients, 10 patients were in Group S, 15 patients were in Group F and 3 patients were in Group L. In Group S, none of them developed DJK, however, DJK was observed 9 of 15 patients in Group F. DJK was developed in all cases in Group L. There is a statistically higher risk for developing DJK when FLV or LEV was selected as LIV (p < 0.05). Conclusion: Selecting SSV for the distal fusion level has been found to be effective for preventing DJK. Selecting distal fusion level proximal to SSV will increase the risk of DJK which may become symptomatic and require revision surgery.
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    PublicationOpen Access
    Effectiveness of posterior structures in the development of proximal junctional kyphosis following posterior instrumentation: a biomechanical study in a sheep spine model
    (Elsevier, 2019) Akgül, Turgut; Sarıyılmaz, Kerim; Özkunt, Okan; Dikici, Fatih; Yazıcıoğlu, Önder; N/A; Korkmaz, Murat; Doctor; School of Medicine
    Introduction: proximal junctional kyphosis – PJK has been defined by a 10 or greater increase in kyphosis at the proximal junction as measured by the Cobb angle from the caudal endplate of the uppermost instrumented vertebrae (UIV) to the cephalad endplate of the vertebrae 1 segments cranial to the UIV. In this biomechanical study, it is aimed to evaluate effects of interspinosus ligament complex distruption and facet joint degeneration on PJK development. Materials and methods: posterior instrumentation applied between T2 – T7 vertebrae using pedicle screws to randomly selected 21 sheeps, divided into 3 groups. First group selected as control group (CG), of which posterior soft tissue and facet joints are protected. In second group (spinosus group, SG) interspinosus ligament complex which 1 segment cranial to UIV has been transected, and third group (faset group-FG) was applied facet joint excision. 25 N, 50 N, 100 N, 150 N and 200 N forces applied at frequency of 5 Hertz as 100 cycles axial to the samples. Then, 250 N, 275 N and 300 N forces applied static axially. Interspinosus distance, kyphosis angle and discus heights was measured in radiological evaluation. Abnormal PJK was defined by a proximal junctional angle greater than 100 and at least 100 greater than the corresponding preoperative measurement. Results: in CG group, average interspinosus distance was 6,6 ± 1.54 mm and kyphosis angle was 2,2 ± 0.46° before biomechanical testing, and they were measured as 9,4 ± 1.21 mm and 3,3 ±0.44° respectively after forces applied to samples. In SG group, average interspinosus distance was 6,2 ± 1.72 mm and kyphosis angle was 2,7 ± 1.01° before experiment, and they were measured as 20,8 ± 5.66 mm and 15,1 ± 2.34° respectively after forces applied to samples. In FG group, average interspinosus distance was 4,8 ± 1.15 mm and kyphosis angle was −1 ± 4.14° before experiment, and they were measured as 11,1 ±1.96mm and 11 ± 2.87° respectively after forces applied to samples. In comparison to group CG, statistically significant junctional kyphosis was seen on both FG and SG group after statistical analysis. (p < 0.05). PJK was seen statistically significant more on SG group than FG group. (p < 0.05). Not any statistically significant difference was seen on measurement of disk distances among three groups. (p > 0.05) Conclusions: protecting interspinosus ligament complex and facet joint unity during posterior surgical treatment for spine deformation is vital to prevent PJK development. Based on our literature review, this is the first biomechanical study that reveals interspinosus ligament complex are more effective on preventing PJK development than facet joints.
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    PublicationOpen Access
    Biomechanical comparison of pull-out strength of different cementation and pedicle screw placement techniques in a calf spine model
    (Springer, 2020) Akgül, Turgut; Pehlivanoğlu, Tuna; Bayram, Serkan; Özdemir, Mustafa Abdullah; Karalar, Şahin; Korkmaz, Murat; Doctor; Koç University Hospital
    Background: we hypothesized that an entire pedicle screw tract cement augmentation has greater strength than traditional techniques. Method: twenty-four fresh frozen calf lumbar spines were randomized into three study groups, each having eight vertebrae: (1) screw cemented after vertebroplasty; (2) fenestrated cemented screw; and (3) cementation of the entire pedicle screw tract. For the right side screws, two pedicle screws were inserted in each vertebra with the standard position in the sagittal plane, whereas the left side screws were placed at a 30 degrees angle craniocaudal plane. From the recorded force-displacement curves, the maximum peak load (failure load) of each screw was determined. The mode of failure was screw stripping at all levels tested. Results: the pull-out strength for standard screw replacement at the sagittal plane was 1843.3 N, 1707.45 N, and 5365.1 N consecutively. The failure load value in the standard position in the sagittal plane in the cementation of the entire pedicle screw tract group was significantly higher than that in the fenestrated cemented screw group and screw cemented after vertebroplasty (p < 0.001 andp < 0.001, respectively). The standard pedicle screw position in the sagittal plane showed a significant pull-out strength than the others (p < 0.001). Conclusion: the pull-out strength of the cementation of the entire pedicle screw tract was 2.5 times higher than the others. The pull-out strength of the pedicle screws in malposition obtained the same strength to the standard positions after the augmentation procedure in our study.
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    PublicationOpen Access
    Quantitative comparison of a laterally misplaced pedicle screw with a re-directed screw. How much pull-out strength is lost?
    (Elsevier, 2018) Şanyılmaz, Kerim; Özkunt, Okan; Gemalmaz, Halil Can; Akgül, Turgut; Sungur, Mustafa; Dikici, Fatih; Baydoğan, Murat; Korkmaz, Murat; Doctor; Koç University Hospital
    Objective: redirecting of a laterally misplaced pedicle screw into the accurate position decreases the pull-out strength due to the reinsertion, lateral wall cortical perforation and widening of the pedicle hole. Thus, this biomechanical study was performed to quantitatively analyze the pullout strength of a redirected laterally misplaced pedicle screw into the accurate position. Methods: thirty pedicules of 15 bovine vertebrae were separated to 3 groups, according to the screw placement method: 1) standard flawless trajectory; 2) trajectory with lateral pedicle wall perforation; 3) trajectory with lateral wall perforation redirected to the standard trajectory. Samples were placed on a universal testing machine and pullout loads were measured. Kruskal-Wallis test was utilized within 95% confidence interval and p value <0.05 to test for the statistical significance. Results: the mean pullout strength was 2891 +/- 654,2 N(1383-3814,5) in Group 1; 817,8 +/- 227,6 N(308,6-1144,9) in Group 2 and 2081,1 +/- 487,7 N(1583,5-2962,5) in Group 3. The results found out to be statistically significant (p<0.05). Inter-group comparisons revealed that lateral pedicle wall perforation significantly decreases the pullout strength (p<0.05) and redirection of the screw increases the strength (p<0.05), however it was still weaker than the screws with flawless standard trajectory but this was not statistically significant (p>0.05). Conclusion: The results of this study confirm that pullout strength of pedicle screw decreases by approximately 71% when the lateral wall is perforated and decreases 28% after redirection to the accurate position.
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    PublicationOpen Access
    Is elective cancer surgery feasible during the lock-down period of the COVID-19 pandemic? Analysis of a single institutional experience of 404 consecutive patients
    (Wiley, 2021) Cesur, Ezgi; Kırış, Talat; Giray, Burak; Kulle, Cemil Burak; Azamat, İbrahim Fethi; Ağcaoğlu, Orhan; Dilege, Ece; Erkan, Murat Mert; Balık, Emre; Bilge, Orhan; Buğra, Dursun; Vatansever, Doğan; Taşkıran, Çağatay; Erus, Suat; Yavuz, Ömer; Tanju, Serhan; Dilege, Şükrü; Tarım, Kayhan; Kiremit, Murat Can; Kılıç, Mert; Canda, Abdullah Erdem; Kordan, Yakup; Akyoldaş, Göktuğ; Solaroğlu, İhsan; Sasani, Mehdi; Gökler, Ozan; Ünsaler, Selin; Altuntaş, Muzaffer Ozan; Hafız, Ayşenur Meriç; Şimşek, Sezai Aykın; Deveci, Mehmet Ali; Korkmaz, Murat; Çakar, Nahit; Ergönül, Önder; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Teaching Faculty; Faculty Member; Researcher; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Faculty Member; Teaching Faculty; Teaching Faculty; Teaching Faculty; Faculty Member; Faculty Member; Doctor; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; N/A; N/A; 175476; 218050; 214689; 18758; 176833; 1758; 193687; 134190; 175565; N/A; 214690; 122573; 327605; N/A; N/A; 116202; 157552; N/A; 102059; N/A; 311179; 167909; 169795; 53676; N/A; 206311; N/A; 198906; 110398
    Background: we aimed to assess the feasibility and short-term clinical outcomes of surgical procedures for cancer at an institution using a coronavirus disease 2019 (COVID-19)-free surgical pathway during the peak phase of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Materials and methods: this was a single-center study, including cancer patients from all surgical departments, who underwent elective surgical procedures during the first peak phase between March 10 and June 30, 2020. The primary outcomes were the rate of postoperative SARS-CoV-2 infection and 30-day pulmonary or non-pulmonary related morbidity and mortality associated with SARS-CoV-2 disease. Results: four hundred and four cancer patients fulfilling inclusion criteria were analyzed. The rate of patients who underwent open and minimally invasive procedures was 61.9% and 38.1%, respectively. Only one (0.2%) patient died during the study period due to postoperative SARS-CoV2 infection because of acute respiratory distress syndrome. The overall non-SARS-CoV2 related 30-day morbidity and mortality rates were 19.3% and 1.7%, respectively; whereas the overall SARS-CoV2 related 30-day morbidity and mortality rates were 0.2% and 0.2%, respectively. Conclusions: under strict institutional policies and measures to establish a COVID-19-free surgical pathway, elective and emergency cancer operations can be performed with acceptable perioperative and postoperative morbidity and mortality.