Browsing by Author "Gemalmaz, Halil Can"

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A Biomechanical Comparison of Tendon Repair with a Knotless Barbed Suture and a Conventional Monofilament Suture Material: An ex-vivo Animal Experiment
(GALENOS YAYINCILIK, 2020-01-01) Gemalmaz, Halil Can
Objective: Our aim is to compare the ultimate tensile strength and stiffness of a 2/0 barbed suture and a 3/0 polypropylene monofilament suture in a porcine tendon repair model. Methods: Sixteen porcine Achilles tendons were transected and separated into two groups. In group I tendons were repaired with a modified knotless four-strand Kessler technique using a 2/0 V-Loc barbed suture. In group II tendons were repaired with a four-strand Kessler technique using a 3/0 monofilament conventional suture and knots were tied. All specimens were biomechanically tested for ultimate tensile strength (UTS) and stiffness. Mode of failure was also noted. Results: Five specimens in group I failed by stripping of the suture from the tendon tissue, three failed due to suture breakage. In group II two out of eight tendons failed by stripping of the suture and remaining six failed by suture breakage. Median UTS value was found to be 85.96 N (range: 63.24) in group I and 64.29 N (range: 56.84) in group II. Median stiffness value of the samples in group I was found to be 5.67 N/mm (range: 4.32) and in group II it was found to be 4.53 N/mm (range: 6.23). The statistical analysis of UTS and stiffness values revealed no significant difference between the groups (p=0.17 and p=0.56 respectively). Conclusion: A knotless Kessler tendon repair made with a 2/0 barbed suture is biomechanically equivalent to a knotted Kessler tendon repair made with a 3/0 conventional polypropylene suture in ex-vivo conditions.
A Novel 3D Printed Custom Antibiotic Spacer Mold for Osteomyelitis Cases which are Prone to Instability
(GAZI UNIV, FAC MED, 2018-01-01) Gemalmaz, Halil Can; Sariyilmaz, Kerim; Ozkunt, Okan; Sungur, Mustafa; Kaya, Ibrahim; Dikici, Fatih
Presence of complex bone defects in osteomyelitis treatment may be challenging for the surgeon. Antibiotic cement spacers take a role in managing these defects. The available techniques and systems of antibiotic cement spacers have their pros and cons. There are cases in which these standard options may fail, mainly due to stability related issues. In this report, we present an antibiotic spacer technique in a very complex bone defect that is prone to failure if managed by routine spacer applications. Anticipating that any standard spacer application methodology will fail, we decided to make our own custom antibiotic cement spacer. We used the patient's uninjured side's tomography data to create a custom 3D spacer mold model with the help of a computer software. Later this 3D spacer mold model was printed with a 3D printer. The print out was sterilized and used to cast a custom antibiotic cement spacer resulting in a perfect fit in the defect.
Analysing the change of sagittal balance in patients with Lenke 5 idiopathic scoliosis
(TURKISH ASSOC ORTHOPAEDICS TRAUMATOLOGY, 2017-01-01) Ozkunt, Okan; Karademir, Gokhan; Sariyilmaz, Kerim; Gemalmaz, Halil Can; Dikici, Fatih; Domanic, Unsal
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
Çocuk ve Adolesan Yaş Grubunda Bel Ağrıları; Yaklaşım, Tanı ve Tedavi
(Acıbadem Mehmet Ali Aydınlar Üniversitesi, 2014-01-01) Önal, Vuslat Sema; Gemalmaz, Halil Can
ÖZET Bel ağrısı, çocuk ve adölesanlarda sık görülen bir yakınmadır. Çocuğun yaşı, yaşam tarzı, yakınmalarının ortaya çıkış şekli ve süresi tanı için önemli ipuç ları içerir. Bunları değerlendirerek, doğru tanıya ulaşmak mümkündür. Etkin konservatif yöntemlerle, çocukluk çağı bel ağrıları çoğunlukla sağaltılabilir.
Comparison of effectiveness of kyphoplasty and vertebroplasty in patients with osteoporotic vertebra fractures
(TURKISH ASSOC ORTHOPAEDICS TRAUMATOLOGY, 2016-01-01) Ates, Ahmet; Gemalmaz, Halil Can; Deveci, Mehmet Ali; Simsek, Sezai Aykin; Cetin, Engin; Senkoylu, Alpaslan
Objective: The aim of this study was to compare the functional and radiological outcomes of vertebroplasty and kyphoplasty in patients with osteoporotic vertebra fractures. Methods: The files of the patients who underwent vertebroplasty or kyphoplasty for osteoporotic vertebrae fractures were retrieved from the archives. Forty-three patients with complete follow-up data were included in the study group. The patients were evaluated for radiological outcomes in terms of local kyphosis angle, wedging index, compression ratio, visual analog pain scale (VAS) and Oswestry Disability Index (ODI). Results: In the study group, kyphoplasty was performed on 24 vertebrae of 22 patients (17 females, 5 males
Does pedicle screw density matter in Lenke type 5 adolescent idiopathic scoliosis?
(LIPPINCOTT WILLIAMS \& WILKINS, 2018-01-01) Sariyilmaz, Kerim; Ozkunt, Okan; Karademir, Gokhan; Gemalmaz, Halil Can; Dikici, Fatih; Domanic, Unsal
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.
Investigation of efficacy of treatment in spinal cord injury: Erythropoietin versus methylprednisolone
(SAGE PUBLICATIONS INC, 2017-01-01) Ozkunt, Okan; Sariyilmaz, Kerim; Gemalmaz, Halil Can; Gurgen, Seren Gulsen; Yener, Ulas; Dikici, Fatih
Background: Investigation of the expression of platelet-derived growth factor (PDGF)-beta and glial fibrillary acidic protein (GFAP) in rats with spinal cord injury as a marker of neurologic recovery between groups treated with erythropoietin (EPO) and methylprednisolone (MP). Methods: Thirty adult female rats were randomly divided into three even groups. A laminectomy was applied to thoracic ninth vertebra and contusion injury was induced by extradural application of an aneurysm clip. Group 1 rats received one-time intrathecal administration of normal saline, group 2 rats received MP, and group 3 rats received EPO. Motor neurological function was evaluated by the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale. Thirty days after the surgery, T8-10 segments of the spinal cords were extracted and the immunohistochemical assay revealed the number of PDGF-beta- and GFAP-positive cells. Results: Evaluation of the last control animal showed that BBB score in the EPO group showed an increase from 1 to 12 (p < 0.05). The immunohistochemical assay revealed that the number of PDGF-beta- and GFAP-positive cells was significantly higher in EPO group (p = 0.000) when compared to MP and control groups. After studying the effect of PDGF-beta expression on the locomotor function, we determined that PDGF-beta expression and locomotor function after a spinal injury has a strong relationship (p < 0.05). Conclusion: EPO seems to better increase the expression of PDGF-beta, thus produce better results in locomotor functions when compared to MP.
Linear Frictional Properties of a Barbed Suture in the Tendon Tissue
(GAZI UNIV, FAC MED, 2019-01-01) Gemalmaz, Halil Can
Objective: The barbed suture has been around for some time with some important theoretical advantages for tendon repairs such as resistance to suture slippage and knotless application. However, these theoretical advantages are not yet proven to be practically important. The literature on the barbed suture for tendon repair has a focus on in-vivo or ex-vivo preclinical investigations of established tenorrhaphy methods. Current literature is poor in knowledge on its fundamental properties thus basic research. Our study attracts attention on the lack of basic research on barbed suture for tendon repair and investigates a barbed suture's linear frictional performance in the tendon. Methods: Thirty-two fresh frozen porcine forefoot digital flexor tendons were separated into four groups of eight tendons. In group 1 a barbed suture was introduced to the tendons 1 cm proximal to the distal cut-end and was advanced through the core of the tendon tissue leaving the distal cut-end at the core. In group 2 the suture was introduced in the same way purchasing 2 cm of tendon tissue, in group 3 and 4 the suture purchase length was 3 and 4 cm respectively. Ultimate tensile strength generated by anchorage of the barbs of the suture in the tendon tissue was assessed with a mechanical testing machine and the results were statistically compared between groups. Results: Mean ultimate tensile strength was found to be 5.4N for group 1, 7.45N in group 2, 4.87N in group 3 and 5.76N for group 4. Intergroup comparison was made with a data set corrected for suture purchase length which was obtained by dividing each sample's ultimate tensile value by the distance of suture purchase length accordingly. Statistical analysis with corrected data set revealed that group 1 versus 2 showed no difference whereas comparison of group 1 vs 3 and group 1 vs 4 showed a significant difference. Discussion: Our results showed that the frictional forces generated by the barbed suture were directly proportional to the suture purchase length only to some extent. Statistical analysis confirmed the direct linear relation between pullout strength and suture purchase length up to 2 centimeters of suture purchase. Pullout strength in samples with 3 and 4 centimeters of suture purchase showed deterioration. Conclusion: The tissue grasping strength of the barbed suture we tested in our study is not directly proportional to the suture purchase length. More basic research on barbed suture for tendon repair is needed to better understand how its theoretical advantages can be appreciated practically. Suture producing companies should investigate and produce barbed sutures specially tailored for tendon repair.
Postoperative mechanical alignment analysis of total knee replacement patients operated with 3D printed patient specific instruments: A Prospective Cohort Study
(TURKISH ASSOC ORTHOPAEDICS TRAUMATOLOGY, 2019-01-01) Gemalmaz, Halil Can; Sariyilmaz, Kerim; Ozkunt, Okan; Sungur, Mustafa; Kaya, Ibrahim; Dikici, Fatih
Objective: Total knee replacement (TKR) is a surgical treatment for final stage gonarthrosis. The lifespan of the prosthetic implants used in TKR surgery is a major interest for the orthopaedic research community. Previously, proper implant alignment of the implants has been advocated for longevity of the TKR surgery. Recently, patient-specific (PSI) instruments have been proposed to improve the mechanical alignment of the TKR by permitting better implant positioning over conventional TKR surgery. The aim of this study is to compare the mechanical alignment results of patients operated with PSIs and conventional instruments. Methods: Two groups of 20 patients chosen in a quasi-random manner have been compared in this study. In the first group femoral distal and tibial osteotomies were made by a PSI which was produced by the patients' computed tomography scans. All osteotomies in the control group were made with the TKR set's routine instruments by conventional means. Patients' preoperative and postoperative mechanical femorotibal angles (mFTA), femoral coronal angles (FCA), tibial coronal angles (TCA) were measured and the number of outliers which showed more than 3 degrees of malalignment were counted in both groups for comparison. Results: The average postoperative mFTA was found to be 2.09 degrees for the PSI group and in was found to be 2.84 degrees for the control which was not statistically significant. The comparison of postoperative FCA and TCA also did not show significant difference between the groups. The number of outliers showing more than 3 degrees of malalignment per group were found to be 1 out of 20 (5\%) for the PSI group and 7 out of 20 (35\%) for the control which was statistically significant. Conclusion: In this study patient-specific instrumentation provided significantly better mechanical alignment compared to conventional TKR for the frequency of outlier cases with malalignment beyond 3 degrees. PSI proved no significant difference when the groups were compared for mFTA, FCA and TCA. Our findings support that PSI may improve TKR alignment by improving the ratio of the outlier patients with marked malalignment. (C) 2019 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V.
Role of a combination dietary supplement containing mucopolysaccharides, vitamin C, and collagen on tendon healing in rats
(TURKISH ASSOC ORTHOPAEDICS TRAUMATOLOGY, 2018-01-01) Gemalmaz, Halil Can; Sanyilmaz, Kerim; Ozkunt, Okan; Gurgen, Seren Gulsen; Silay, Sena
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 beta 1 (TGF-beta 1) 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
The effect of tourniquet usage on cement penetration in total knee arthroplasty A prospective randomized study of 3 methods
(LIPPINCOTT WILLIAMS \& WILKINS, 2018-01-01) Ozkunt, Okan; Sariyilmaz, Kerim; Gemalmaz, Halil Can; Dikici, Fatih
Background: It is a randomized study to compare cement penetration on x-rays after total knee arthroplasty (TKA) among 3 different ways to use tourniquets