Okan Ozkunt
Acıbadem University
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Featured researches published by Okan Ozkunt.
Journal of Pediatric Orthopaedics | 2017
Kerim Sariyilmaz; Okan Ozkunt; Mustafa Sungur; Fatih Dikici; Unsal Domanic
Background: Posterior spinal instrumented fusion has received widespread acceptance in adolescent idiopathic scoliosis (AIS) treatment, there have been some potential complications resulted from screw misplacement. Esophagus is one of the vital structures close to the upper thoracic vertebras and is at risk for potential injury. Methods: A 15-year-old girl who underwent posterior instrumented fusion for AIS was admitted to our department 10 years later with a complaint of dysphagia due to an esophageal perforation from a malpositioned T4 pedicle screw (PS). After implant removal and nasogastric tube placement, oral feeding was started after 3 days and the patient was discharged from hospital after 1 week. Results: In 12 weeks, the esophageal perforation healed without complications. Conclusions: This is the first case report of esophageal perforation by a posterior PS in an AIS patient. Esophagus is close to the upper thoracic vertebras and an anterior cortical perforation can cause esophageal injury if longer than 35 mm PSs are used. This unusual but potential complication must be kept in mind in scoliosis surgery. Level of Evidence: Level IV—case report.
Acta Orthopaedica et Traumatologica Turcica | 2013
Harzem Ozger; Okan Ozkunt; Turgut Akgül; Yavuz Saglam
Desmoid tumors or aggressive fibromatoses are rare, non-encapsulated, infiltrative and locally aggressive tumors originating from deep musculo-aponeurotic structures. Traditionally, preferred treatment method for desmoid tumors is wide local excision. Depending on the side and type of resection, the reported local recurrence rates range from 15 to 77%. Similarly, in our institution there is a significant recurrence rate (24%) in patients who underwent surgery for desmoid tumor. After several recurrences, amputation may be inevitable following repeating vascular and nerve reconstructions. There is a need for a nonviable barrier in order to prevent the invasion of the viable tumor to the neurovascular structures which are also viable tissues. Depending on this need, we present two cases that we used synthetic vascular graft in their operations to cover neurovascular structures in order to prevent tumor invasion. For patients who are not suitable for radiotherapy and the neurovascular structures need to be secured because of the risk of local recurrence, this method can prevent possible future invasion of vessels and nerves.
International Journal of Surgery Case Reports | 2017
Halil Can Gemalmaz; Kerim Sariyilmaz; Okan Ozkunt; Mustafa Sungur; İbrahim Kaya; Fatih Dikici
Highlights • Skeletal deformity surgery is a difficult procedure which requires meticulous planning.• Good results demand precise application of the surgical plan during the surgery.• 3D software helps to make precise surgical plans and design case specific surgical tools.• 3D printing of case specific tools renders surgery easy and precise.
Acta Orthopaedica et Traumatologica Turcica | 2017
Okan Ozkunt; Gökhan Karademir; Kerim Sariyilmaz; Halil Can Gemalmaz; Fatih Dikici; Unsal Domanic
Objective The aim of this study was to evaluate preoperative and postoperative spinopelvic parameters and the influence of lowest instrumented vertebrae on sagittal parameters in Lenke 5 Adolescent Idiopathic Scoliosis (AIS) patients. Methods A total of 42 patients (37 females, 5 males; mean age: 16.71 ± 3.46 years) were included in the study. Preoperative and postoperative last follow up lumbar lordosis (LL), thoracic kyphosis (TK), pelvic tilt (PT), pelvic incidence (PI) and sacral slope (SS) angles measured. By stopped fusion in L3, L4 or L5 we divided the group into three parts. Results Mean follow-up was 43 months. Preoperatively, the mean TK and LL were 36.8° and 55.3°. At the last follow up, the mean TK and LL were 27.1° and 49.0° degrees, respectively. Preoperatively, the mean PI, PT and SS were 53.3°, 16.1° and 37.4° degrees. At the last follow up, the mean PI, PT and SS were 52.7°, 19.9° and 33.0° respectively. Significant differences were observed for SS (p = 0.003), TK (p = 0.004), LL (p = 0.012) and PT (p = 0.013) postoperatively for all patients. According the L3 and L4 groups there is significant difference in SS, LL (p = 0.013) and PT (p = 0.018) which means a significant decrease occurs in SS and LL when the distal fusion level changes from L3 to L4 but significant increase in PT in L3 group to compensate spinopelvic change after surgery. Conclusion The selection of more distal level for fusion adversely affects the compensation mechanisms of sagittal balance in Lenke 5 AIS patients. Level of Evidence Level IV, Therapeutic study.
International Journal of Surgery Case Reports | 2015
Kerim Sariyilmaz; Baris Gulenc; Okan Ozkunt; Fatih Dikici; Onder Yazicioglu
Highlights • Insufficiency fractures due to antiepileptic drug use is one of the rare cause.• Insufficiency fractures should be kept in mind for joint and bone pain with a history of long term anti-epileptic drug use.• Carbamazepine could be a result of insufficiency fracture.
Medicine | 2018
Kerim Sariyilmaz; Okan Ozkunt; Gökhan Karademir; Halil Can Gemalmaz; Fatih Dikici; Unsal Domanic
Abstract The aim of this study is to compare the effects of high versus low implant density on correction in Lenke type 5 adolescent idiopathic scoliosis (AIS) patients. A retrospective study of 59 Lenke type 5 AIS patients treated at a single institution were divided into to 2 groups according to implant density. Implant density, preoperative, early postoperative, and last follow-up thoracolumbar/lumbar (TL/L) curves were measured. Thirty-one constructs were high and 28 constructs were low density. The groups were similar in terms of age, sex, Cobb angle, and follow-up time. Mean implant density in low density group and high density group was 75.4% and 96.6%, respectively. High versus low-density comparison showed that there is no significant difference with regard to curve correction in early postoperative and last follow-up periods. The results show that pedicle screw density being low or high, does not affect curve correction rates in the short and long term in our patients.
Journal of the American Podiatric Medical Association | 2018
Kerim Sariyilmaz; Ilker Eren; Okan Ozkunt; Mustafa Sungur; Onder Kilicoglu; Fatih Dikici
BACKGROUND Gout is a purine metabolism disease. Tophaceous gout may cause joint destruction and other systemic problems and sometimes may be complicated by infection. Infection and sinus with discharge associated with tophaceous gout are serious complications, and treatment is difficult. We present a patient with tophaceous gout complicated by infection and discharging sinus treated by bilateral amputation at the level of the first metatarsus. METHODS A 43-year-old man previously diagnosed as having gout, and noncompliant with treatment, presented with tophaceous gout associated with discharging sinus and infection on his left first metatarsophalangeal joint. Because of the discharging sinus associated with the tophaceous deposits, the soft-tissue and bony defects, and the noncompliance of the patient, amputation of the first ray was undertaken, and a local plantar fasciocutaneous flap was used to close the defect. After 8 months, the patient was admitted to the emergency department with similar symptoms in his right foot, and the same surgical procedure was performed. RESULTS One year after the second surgery, the patient had no symptoms, there was no local inflammatory reaction over the surgical areas, and laboratory test results were normal. CONCLUSIONS Gout disease with small tophi often can be managed conservatively. However, in patients with extensive lesions, risk of superinfection justifies surgical treatment. Results of complicated cases are not without morbidity; therefore, early surgical treatment may prevent extremity loss and further complications. In severe cases, especially with compliance issues, amputation provides acceptable results.
Asian Spine Journal | 2018
Turgut Akgül; Kerim Sariyilmaz; Murat Korkmaz; Okan Ozkunt; Özcan Kaya; Fatih Dikici
Study Design Retrospective analysis of adolescent idiopathic scoliosis. Purpose This 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 The 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 A 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 The 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 When the distal instrumentation level in AIS surgery is below L3, a significant change in PT and SS (pelvic parameters) is anticipated.
Acta Orthopaedica et Traumatologica Turcica | 2018
Halil Can Gemalmaz; Kerim Sariyilmaz; Okan Ozkunt; Seren Gülsen Gürgen; Sena Silay
Objective The aim of this study was to investigate the effect of mucopolysaccharide, vitamin C, and collagen supplementation on the healing of Achilles tendon in rats. Methods Sixteen rats were separated into 2 groups. Both Achilles tendons of all rats were transected 5 mm above the insertion and repaired using a Kessler suture. After the surgical repair, the study group received the daily recommended amount of the supplement by gastric gavage, while the control group received a placebo. At the end of the third week, the animals were sacrificed. The biomechanical properties of the groups were compared with ultimate tensile strength and stiffness tests. The biological properties of the 2 groups were assessed with a histomorphometric comparison to determine the amount of collagen type I (COL1), proliferating cell nuclear antigen (PCNA), and transforming growth factor β1 (TGF-β1) expression in 3 different tissue subgroups (collagen matrix, tenocytes, and endotenon fibroblasts). Results Analysis of histomorphometric results revealed that the rats receiving dietary supplements demonstrated a significant increase in PCNA (mean value of 86 in the control group and 168.85 in the trial group; p < 0.05) and TGF-β1 (mean value of 87.57 in the control group and 161.85 in the trial group; p < 0.05) in the endotenon fibroblasts of the repair site. However, there was no difference between the groups in PCNA or TGF-β1 when the collagen matrix and the tenocytes of the repair site were examined. Furthermore, no significant difference could be found between groups in COL1 in any of the 3 tissue subgroups (collagen matrix, tenocytes, and endotenon fibroblasts). The statistical analysis also indicated that the rats receiving supplements did not demonstrate a significant increase in the ultimate tendon tensile strength or stiffness. Conclusion The results of this study revealed no advantage to the oral administration of the trial supplement in collagen synthesis or biomechanical properties in rats after 3 weeks using the presented study design. However, the increased expression of PCNA and TGFβ1 seen in the endotenon fibroblasts of the repair site might play a role in the continuum of tendon healing.
Acta Orthopaedica et Traumatologica Turcica | 2018
Murat Korkmaz; Kerim Sariyilmaz; Okan Ozkunt; Halil Can Gemalmaz; Turgut Akgül; Mustafa Sungur; Fatih Dikici; Murat Baydogan
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.