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  • Küçük Resim
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    Effectiveness of posterior structures in the development of proximal junctional kyphosis following posterior instrumentation: A biomechanical study in a sheep spine model
    (Turkish Assoc Orthopaedics Traumatology, 2019) Korkmaz, Murat; Akgül, Turgut; Sarıyılmaz, Kerim; Özkunt, Okan; Dikici, Fatih; Yazıcıoğlu, Önder
    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 distancewas 6,6 +/- 1.54 mm and kyphosis angle was 2,2 +/- 0.46 degrees before biomechanical testing, and they were measured as 9,4 +/- 1.21 mm and 3,3 +/- 0.44 degrees 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 degrees before experiment, and they were measured as 20,8 +/- 5.66 mm and 15,1 +/- 2.34 degrees respectively after forces applied to samples. In FG group, average interspinosus distancewas 4,8 +/- 1.15 mm and kyphosis angle was -1 +/- 4.14 degrees before experiment, and they were measured as 11,1 +/- 1:96 mm and 11 +/- 2.87 degrees 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. (C) 2019 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V.
  • Küçük Resim
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    Prognostic factors, treatment methods and survival time in hepatocellular carcinoma: A decade of experience at a single center
    (PMC, 2022) Sunar, Ali; Korkmaz, Murat
    Background and Aim: The objective of this study was to investigate the etiology, prognostic factors, treatment methods, and effects of treatment on survival in cases of hepatocellular carcinoma (HCC). Materials and Methods: This was a retrospective study of 158 patients diagnosed with HCC at a single hospital between the years 2000 and 2010. Results: The etiological factor of HCC was the hepatitis B virus (HBV) in 53.2% of the cases, the hepatitis C virus (HCV) in 21.5%, alcohol use in 6.3%, HBV+alcohol in 5.7%, HCV+alcohol in 1.9%, HBV+HCV in 1.9%, and the cause was unknown in 9.5%. Of the 158 patients, 120 were treated at the study hospital, and complete follow-up data were available for 81. The mean length of follow-up was 17.9 months (range: 0.6–124 months). Multivariate analysis indicated that a lesion size >5 cm, Child-Pugh class C, a high creatinine level, and a distant metastasis were prognostic factors of reduced survival. Conclusion: HBV was the most frequent cause of HCC in this study group, followed by HCV. The most effective treatment methods for survival were liver transplantation and hepatic resection. A lesion size >5 cm, Child-Pugh class C, a high creatinine level, and distant metastasis were independent poor prognostic factors for survival.