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Öğe Bilateral traumatic patella fracture: a case report(Turkish Joint Diseases Foundation, 2011) Cirpar, Meric; Turker, Mehmet; Aslan, Arif; Yalcinozan, MehmetPatellar fractures are uncommon injuries and account for approximately 1% of all fractures. In this article, a 35-year-old male patient who sustained a collision deceleration accident with bilateral comminuted transverse patellar fractures is presented. For this patient, open reduction and internal fixation with tension band technique, using two Kirschner wires and cerclage wire was applied for both fractures. At the first postoperative day, isometric quadriceps and active range of motion exercises were begun and the patient was allowed to walk full weight bearing with two crutches while both extremities were immobilized in a hinged brace allowing maximum 30 degrees of flexion. At postoperative fourth week brace immobilization was terminated. However, the patient was advised to use crutches for two weeks more to prevent any complications that may arise during walking because of the bilaterally of the injury. At six weeks solid union was achieved. During the last visit at postoperative second year, the patient had no complaints and the range of motion was full. In this paper a case of bilateral patella fractures is presented as a consequence of a dashboard injury, and the pathomechanical and therapeutical aspects of such an injury is discussed.Öğe Cementless Total Hip Arthroplasty With Modified Oblique Femoral Shortening Osteotomy in Crowe Type IV Congenital Hip Dislocation(Churchill Livingstone Inc Medical Publishers, 2013) Kilicoglu, Onder I.; Turker, Mehmet; Akgul, Turgut; Yazicioglu, OnderMidterm results of cementless total hip arthroplasty in patients with Crowe type IV congenital dislocation of the hip were evaluated. A modified oblique subtrochanteric shortening osteotomy was used in all patients. A cylindrical femoral stem was used in all patients to stabilize the osteotomy. Mean follow-up was 82 months in 20 hips of 16 patients. Mean Merle D'Aubigne pain score increased from 2.52 to 5.65 points, function score improved from 4.0 to 5.3 points, and mobility score improved from 3.95 to 5.35. Mean greater trochanter height relative to the estimated hip center was 6.8 +/- 2.0 cm preoperatively and -1 +/- 0.2 cm postoperatively. Complications were dislocations in 3 patients, which were successfully managed without redislocation and fracture of greater trochanter in 3 patients, which healed uneventfully in 2 but with residual Trendelenburg gait in one. Total hip arthroplasty with modified oblique subtrochanteric shortening osteotomy is an effective technique for the treatment for Crowe type IV hip dislocation.Öğe Clamp fixation to prevent unfolding of a suture knot decreases tensile strength of polypropylene sutures(Springer, 2012) Turker, Mehmet; Yalcinozan, Mehmet; Cirpar, Meric; Cetik, Ozgur; Kalaycioglu, BarisPurpose Although sutures evolved in last decade and the product spectrum broadened largely, they can be still classified into two: monofilament and multifilament. Sutures are the mainstay of orthopedic procedures like fascial closures, tendon repairs or tenodesis. In every repair, a suture loop is created. This suture loop is prone to failure due to suture elongation, knot slip and suture breakage. As the knot is the stress riser in a suture loop, the majority of acute loop failure occurs just adjacent to the knot. Monofilament sutures have higher bending stiffness and tendency to untie than multifilament sutures. The first throw of monofilament sutures have tendency to untie, which decrease loop tension and result in loss of achieved tissue approximation. Methods Although a common practice is to fix the first throw via a clamp before the locking one is tied, it can be hypothesized that a potential deforming effect can lead to a decrease in ultimate failure load of a monofilament suture loop. Results Fixing the first throw significantly reduced the ultimate failure load of monofilament nonabsorbable polypropylene sutures (Prolene) (62.2 +/- 8 N vs. 72.7 +/- 9 N, p = 0.019). The ultimate failure load achieved by monofilament sutures Polyglyconate (Maxon) and Nylon (Ethilon) and braided absorbable Polyglactin (Vicryl) were not affected by fixing the first throw. Conclusion Under microscopic examination, polypropylene sutures were found to be deformed by clamp fixation, while the others were not. Polypropylene sutures can be easily damaged when it is fixed by a clamp during knot tying. Presented data demonstrated that in real surgical situations clamp fixation of polypropylene knots can damage the suture loop and carry the risk of acute failure of repair site during early rehabilitation.Öğe Comparison of two techniques in achieving planned correction angles in femoral subtrochanteric derotation osteotomy(Lippincott Williams & Wilkins, 2012) Turker, Mehmet; Cirpar, Meric; Cetik, Ozgur; Senyucel, Cagri; Tekdemir, Ibrahim; Yalcinozan, MehmetIncreased femoral anteversion in cerebral palsy alters biomechanics of gait. Femoral subtrochanteric derotational osteotomies are increasingly performed to improve gait in cerebral palsy. The amount of angular correction can be determined and planned preoperatively but, accuracy in achieving planned angular correction has not been tested experimentally before. The aim of this study was to evaluate the accuracy of the two techniques in achieving planned angular correction. Sixteen dry femora were used in this study. Specimens in both groups were derotated to achieve a desired amount of correction with two different techniques, consecutively. In technique one, the cross section of the femur was assumed to be circular and the desired amount of angular correction was calculated and expressed in terms of surface distance by a geometric formula (surface distance = 2 x pi x radius of femur). In both groups, derotations were made based on this surface distance calculation. Consecutively the same specimens were derotated by pins and guide technique. Femoral anteversion of specimens were measured before and after derotation by computerized tomography. There was a statistically significant differance in planned and achieved correction angles (P = 0.038) in both subgroups derotated by the surface distance technique. When the two techniques were compared, there was significant difference (P = 0.050) between high magnitude correction subgroups (subgroups 2 vs. 4). In conclusion, the results of this study highlighted the difficulty in achieving accurate derotation angles. Derotations based on guide-pins technique yielded more accurate results than derotations based on surface distance technique. In addition, surface diameter technique was not suitable when higher degrees of derotations are needed. In achieving a planned derotation angle two techniques are described for accuracy. Both the techniques have potential pitfalls resulting in malrotations. Surgeons must be aware of these obstacles and try to avoid them. J Pediatr Orthop B 21: 215-219 (C) 2012 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.Öğe Distal medial epicondylectomy. A modification of partial medial epicondylectomy for cubital tunnel syndrome: preliminary results(Springer, 2012) Cirpar, Meric; Turker, Mehmet; Ozuak, Cem SeyfiThe medial epicondyle behaves as a fulcrum and a pulley that tethers the ulnar nerve during flexion. Excision of the distal half of the medial epicondyle sets the point of contact of the bone with the nerve proximally and decreases the traction effect of the medial epicondyle on the ulnar nerve. In this study, we aim to investigate the surgical and clinical results of excision of the distal half of the medial epicondyle in cubital tunnel syndrome (CuTS). Cubital tunnel release with excision of the distal half of the medial epicondyle was performed in 19 patients. The patients were evaluated preoperatively and postoperatively with clinical examinations, McGowan and Wilson-Krout scores, Semmes-Weinstein monofilament and two-point discrimination tests, and grip and pinch strength measurements. A one-grade improvement in McGowan classification was observed in 79 % of patients and a two-grade improvement in 21 % of patients at the time of the first postoperative examination. At 24 months after surgery, 18 patients reported the Wilson-Krout scores as excellent (95 %). Statistically significant improvements in sensory and motor strength measurements were achieved at all postoperative examinations. The objective and subjective outcome measures achieved with distal medial epicondylectomy are comparable with other epicondylectomy techniques. The complication rates seem to be lower than those of total or partial medial epicondylectomy. This procedure is an acceptable and safe alternative for the surgical treatment of CuTS.Öğe Dorsal cutaneous innervation of the hand with respect to anatomical landmarks: is there a safe zone?(Turkish Joint Diseases Foundation, 2012) Cirpar, Meric; Esmer, Ali Firat; Turker, Mehmet; Yalcinozan, MehmetObjectives: In this study, we aimed to define the borders of the triangular area between the radial and dorsal nerves on the dorsum of the hand and to determine its dimensions using measurements between anatomic landmarks. Materials and methods: We statistically analyzed the relation between the distance from Lister's tubercle to the blending point of the central branches of radial and ulnar nerves and the distance between styloids on 14 hands of seven adult human cadavers (5 males, 2 females). The distances of nerve branches to vertical lines drown distally from both styloid processes were also compared with interstyloid distances to help in presuming the course of these nerves. Results: No statistical constant correlation was determined between the measurements. Neither the height of the triangular area nor the courses of both nerves seemed to be quantitatively related to any measurements between the anatomical landmarks. Conclusion: Variability in these measurements in our study indicates that there is no surgical safe zone on the dorsum of the hand.Öğe The effectivity of magnetic resonance imaging findings in the diagnosis of bucket handle meniscal tears(Turkish Joint Diseases Foundation, 2012) Turker, Mehmet; Cetik, Ozgur; Cirpar, Meric; Yalcinozan, Mehmet; Comert, Ruhi Baris; Simsek, TalatObjectives: This study aims to test the efficacy of magnetic resonance imaging (MRI) evaluation by a group who were blinded to the arthroscopic diagnosis in patients with known bucket handle meniscal tears. Patients and methods: In this study, MRI scans of 28 patients who were operated due to bucket handle meniscal tear with sufficient documentation were evaluated. Radiographic evaluation was performed by two different groups, including an orthopedist and radiologist. In the first group, evaluation of MRI scans was performed by the specialists who were aware of the arthroscopic diagnosis and marked the defined MRI signs of bucket handle meniscal tear. In the second group, evaluation was done, remaining blinded to the diagnosis, with only initial complaints at admission. The second group also evaluated the MRI scans and marked the pathologic signs. The sensitivity of radiological signs marked by both groups was compared. Invariables were found using blinded evaluation. Results: Double posterior cruciate ligament and free fragment in the intercondylar notch were invariable sensitivities found in the MRI scans by blinded evaluation. The sensitivity of coronal truncation, anterior flip and any free fragment signs were significantly decreased in the setting of blinded evaluation. Conclusion: Preoperative differentiation of reparable bucket-handle tears from irreparable is of utmost importance. As meniscal repair improves knee stability and functional results, surgical repair of meniscal injuries particularly in younger individuals who are scheduled for anterior cruciate ligament reconstruction have a positive effect on clinical outcomes.Öğe The efficacy and safety of limited incision technique in carpal tunnel release(Turkish Joint Diseases Foundation, 2011) Cirpar, Meric; Ari, Mahmut; Turker, Mehmet; Eksioglu, M. Fatih; Cetik, OzgurObjectives: This study aims to determine the safety and symptomatic and functional efficacy of median nerve decompression with 3 cm limited incision in carpal tunnel syndrome surgery. Patients and methods: Carpal tunnel release with a 3 cm limited palmar incision was performed on 91 hands in 83 patients. Patients were evaluated with Boston Carpal Tunnel Questionnaire, grip strength and pinch strength measurements, Semmes-Weinstein Monofilament test and two-point discrimination tests preoperatively, and at postoperative 3(rd) and 6(th) months. The pre- and postoperative mean values for these assessment criteria were statistically analyzed by paired samples t-test. The symptoms, physical findings, electroneuromyography carpal tunnel syndrome severity scores of the patients were evaluated using descriptive statistical analyses. Results: At postoperative evaluation, there was a statistically significant increase in Boston Carpal Tunnel Questionnaire scores, grip and pinch strengths, and sensory tests results of the patients when compared with preoperative values. No complications other than pillar pain were encountered. Conclusion: Carpal tunnel release with a 3 cm limited incision technique appears to be effective when compared with classical open, endoscopic and mini incision techniques. The rate of complications is lower than that of these techniques. In conclusion, a 3 cm limited incision is both effective and safe in carpal tunnel release.Öğe Histological and biomechanical effects of zoledronate on fracture healing in an osteoporotic rat tibia model(Turkish Joint Diseases Foundation, 2016) Turker, Mehmet; Aslan, Arif; Cirpar, Meric; Kochai, Alauddin; Tulmac, Ozlem Banu; Balci, MahiObjectives: This study aims to investigate the effects of zoledronate therapy on histological and biomechanical properties of bone healing via a fracture model generated on osteoporotic rat tibiae. Materials and methods: Ovariectomized 40 Wistar-Dawley female rats weighing 300 g to 350 g were used in the study. After one week, 2 IU/g heparin injection was started subcutaneously. After four weeks of daily injections, osteoporosis was ensued proven with bone mineral density measurements. Osteoporotic rats were separated into four equal groups randomly as group A (control), group B (calcium and vitamin D), group C (0.1 mg/kg subcutaneous zoledronic acid), and group D (calcium and vitamin D / 0.1 mg/kg subcutaneous zoledronic acid). Six weeks later, all rats were sacrificed, their tibiae were resected, and histopathologic and biomechanical studies were performed. Results: Group C (30.2 +/- 1 Nm) and group D (33.3 +/- 3 Nm) had significantly higher peak torque values than group A (21.6 +/- 6 Nm) and group B (23.6 +/- 4 Nm) (p=0.007 and p=0.005, respectively). Group C (1.8) and group D (2.0) had higher stiffness values than group A (1.4) and group B (1.7); however, the difference was not statistically significant (p>0.05 for all). Conclusion: According to histopathological and biomechanical test results, single dose zoledronic acid treatment improves fracture healing in an osteoporotic rat fracture model. Orally administered daily calcium and vitamin D treatment had no effect on fracture healing. There was no additional improvement in fracture healing when calcium and vitamin D treatment was added to zoledronic acid treatment. Positive effects of zoledronic acid treatment on osteoporotic fracture healing and callus quality should be shown by future clinical studies.Öğe Loop security and tensile properties of polyblend and traditional suture materials(Springer, 2011) Turker, Mehmet; Kilicoglu, Onder; Salduz, Ahmet; Bozdag, Ergun; Sunbuloglu, EminTensile and knot properties of new generation (polyblend) and traditional suture materials in orthopedic surgery were investigated in standard laboratory conditions. Study focused on Fiberwire No. 5 and 2, Ethibond No. 5, 2 and 00, Orthocord No. 2, MaxBraid No. 2, Prolene No. 0 and 00, PDS No. 0 and 00, and Vicryl No. 2, 0 and 00. A 27-cm suture loop was fastened with 10 knots for ten samples for each type. Test parameters were tensile load to failure, elongation at failure point and knot slippage, and volume of 10-fold knots. Results were compared using ANOVA test. Failure load of No. 5 Fiberwire (625.0 +/- A 30.0 N) was significantly higher compared to all other suture types. Tensile strengths of MaxBraid No. 2 (287 +/- A 11 N) was significantly stronger compared to two other No. 2 polyblend sutures types and Ethibond No. 5. Knot slippage of Fiberwire No. 5 (14 +/- A 1.9 mm) was significantly higher compared to all other suture types. Ethibond No. 2 (0.1 +/- A 0.3 mm) had the lowest knot slippage. Elongation at the failure point of Fiberwire No. 2 (5%) was significantly lower than all other suture types. Mean calculated knot volume of #5 Fiberwire (73 +/- A 6.9 mm(3)) was significantly higher compared to #5 Ethibond (53 +/- A 4.8 mm(3)). Results of the study proved presence of significant differences between tensile and knot properties of various suture types and sizes. Loop security of larger diameter sutures is not always higher than thinner sutures. Suture elongation and knot slippage are important failure modes for high-diameter sutures and short-suture loops.Öğe Migration of broken K-wires into the achilles tendon from a ostheosynthesed medial malleolar fracture(Springer, 2011) Turker, Mehmet; Cirpar, Meric; Yalcinozan, MehmetKirschner (K-) wires are often used for osteosynthesis of many types of fractures. Dislocation and migration through the tissues, especially when used for shoulder girdle fractures, have been reported previously. K-wire migration after surgery of pelvis and knee was reported before. To the authors' knowledge, broken and migrated K-wires after ankle fractures were not reported before. Here, we report a case with broken and migrated K-wires after open reduction and internal fixation of a medial malleolar fracture.Öğe Postarthroscopy osteonecrosis of the knee(Springer, 2015) Turker, Mehmet; Cetik, Ozgur; Cirpar, Meric; Durusoy, Serhat; Comert, BarisSpontaneous subchondral osteonecrosis of the knee joint confined to a localized area of one condyle can occur after arthroscopic procedures. Meniscal tears, arthroscopic meniscectomy, and radiofrequency chondroplasty are aetiological factors in the development of osteonecrosis. The aim of this study was to investigate whether the incidence of osteonecrosis increased when mechanical or radiofrequency chondroplasty was used in conjunction with arthroscopic meniscectomy. In this prospective clinical trial, arthroscopic meniscectomy was the primary treatment in 75 patients (mean age 40 +/- A 13) with stage II and III degenerative changes on the articular cartilage. Patients had to meet the following criteria: 1) have preoperative MRI and plain film radiographs showing no evidence of osteonecrosis; 2) be symptomatic for at least 6 weeks before the preoperative MRI; and 3) have arthroscopically confirmed stage II or III chondral lesion. A preoperative MRI was performed for all patients. For treatment of chondral lesions, debridement with a shaver or chondroplasty with a monopolar RF energy system was used. Patients were divided into three treatment groups. Partial meniscectomy of the medial or lateral (or both) menisci was performed on all patients, but patients in group 2 additionally received mechanical debridement of the chondral lesion, and those in group 3 were additionally treated with RF chondroplasty. Patients in group 1 were treated with partial meniscectomy alone. Patients were re-examined after 6 months, at which time a repeat MRI was performed. Development of osteonecrosis was detected during the postoperative MRIs of five patients: two in group 1, two in group 2, and one in group 3. The addition of mechanical or RF chondroplasty to meniscectomy did not increase the number of patients with osteonecrosis. Also, RF chondroplasty, which is commonly proposed to be an aetiological factor, resulted in a decrease in the number of patients that developed osteonecrosis. II.Öğe Recovery Studies on RDX from Decommissioned Munitions(Gazi Univ, 2024) Altin, Soner; Kose, Ozge; Metin, Aysegul Ulku; Turker, MehmetMunitions become obsolete due to the expiration of their shelf life, storage, or inappropriate conditions during use. In this study, it was aimed to recover and purify RDX from waste Composition-B (Comp-B) explosive, which is a mixture of 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), which is the most commonly used as the main fusing agent in military munitions. Waste Comp-B samples were obtained from the munition in two different ways, and different RDX recovery percentages and purity were achieved. Comp-B was obtained both mechanically directly from the ammunition and through the recycling process by melting the main filling of the ammunition with hot water and steam method. TNT was removed from the samples obtained by both methods by utilizing the solubility differences of TNT and RDX in Toluene and RDX was obtained (rRDX). The recovery efficiency was 94% for Comp-B obtained by the mechanical method and 77% for the hot water/steam melting method. As a result of the subsequent purification process, RDX purity for both methods was calculated and determined to be more than 99%.Öğe Revision of the failed pedicle screw in osteoporotic lumbar spine: Biomechanical comparison of kyphoplasty versus transpedicular polymethylmethacrylate augmentation(Turkish Joint Diseases Foundation, 2012) Derincek, Alihan; Turker, Mehmet; Cinar, Murat; Cetik, Ozgur; Kalaycioglu, BarisObjectives: In this study, we aimed to compare of kyphoplasty versus transpedicular polymethylmethacrylate (PMMA) augmentation biomechanically in the revision of the failed pedicle screw in osteoporotic lumbar spine. Materials and methods: Bone mineral density (BMD) of, lumbar vertebrae collected from four bovines were measured., Each vertebra was decalcified with hydrochloric acid solution to obtain osteoporotic specimens. Primary polyaxial pedicle screws, were inserted into the pedicles and pulled out until they failed. The pullout strength results of all specimens were recorded. Revision pedicle screws were randomly inserted into the same pedicles by either pedicle hole PMMA augmented (group 1) or kyphoplasty (Xvoid (TM)) PMMA augmented pedicle screws (group 2). The pullout strength results of all specimens were re-recorded. Results: The mean BMD significantly decreased from 1.686 +/- 227.9 g/cm(2) to 1.432 +/- 157.1 g/cm(2) following decalcification (p<0.001). In group 1, the mean pullout strength of primary screws significantly decreased from 3443 +/- 1086 N/m(2) to 2088 +/- 924 N/m(2) following pedicle screw augmentation (p=0.006). In group 2 the mean pullout strength of primary screws decreased from 3702 +/- 1063 N/m(2) to 3664 +/- 1057N/m(2) following kyphoplasty augmentation (p=0.934). Pedicle screw augmentation group achieved significantly lower pullout strength values than kyphoplasty pedicle hole augmentation group (p=0.002). Conclusion: Although pedicle hole PMMA augmentation is the gold standard for the failed screws in an osteoporotic bone, kyphoplasty augmented pedicle screw seems to be more effective method increasing the pullout strength.Öğe Rotational deformity affects radiographic measurements in distal radius malunion(Springer, 2011) Cirpar, Meric; Gudemez, Eftal; Cetik, Ozgur; Turker, Mehmet; Eksioglu, FatihMalunited distal radius fractures are 3D deformities. The preoperative evaluation of the deformity and surgical planning are usually depended on plain radiographic measurements for corrective osteotomies. In most of the cases, the rotational deformity is disregarded in preoperative planning. We aimed to clarify the effect of rotational deformity on radial inclination and dorsal or volar tilt measurements, which are commonly used as radiologic parameters. This study was performed on standard left radius saw bone models. The malunion models were prepared according to AO distal radius fracture classification system in four main and seventeen subgroups. The differences between the mean radial inclination, volar or dorsal tilt measurements performed on plain radiographies and gold standard values were statistically analyzed. Results showed that rotational deformity causes faulty measurements of radial inclination and dorsal tilt on plain radiographies which may be a contributing factor for unsatisfactory clinical results of corrective osteotomy. We suggest 3D preoperative evaluation of the deformity if possible.Öğe Vascularity and histology of fetal labrum and chondrolabral junction: its relevance to chondrolabral detachment tears(Springer, 2012) Turker, Mehmet; Kilicoglu, Onder; Goksan, Bora; Bilgic, BilgeRecently, acetabular labral tears were recognized as a source of hip pain. Most of these tears were found to be localized at the chondrolabral junction. The purpose of this study was to evaluate the chondrolabral junction in reference to its collagen fiber orientation and its vascularity, which might be used to explain the preponderance of labral tears. Eighteen formalinized fetuses with a mean gestational age of 17 weeks (range: 11-24 weeks) were examined. The acetabuli were removed en bloc with the proximal femur for ease of orientation. The acetabuli were prepared and examined in four quadrants, namely, anterior, superior, posterior, and inferior. The staining pattern of the posteroinferior labrum was more dense than the anterosuperior labrum, due to its high collagen content. Collagen fibers in the posteroinferior quadrants were oriented perpendicularly to the chondrolabral junction, while those in the anterosuperior quadrants had a parallel oriented. Perpendicular collagen orientation and high collagen content may explain the stronger anchorage of the labrum to the bony acetabulum in posteroinferior quadrants. All of the vessels supplying the labrum originate from the capsular connective tissue and traverse the body of the labrum to reach the articular side. None of these vessels traverse the chondrolabral junction to reach the bony acetabulum. The total number of blood vessels was significantly higher in the capsular zone than in the articular zones. The number of blood vessels did not differ between the acetabular quadrants. In an effort to understand the chondrolabral junction tears, we can conclude that collagen content and fiber orientation may represent the histological basis for the predominance of tears at the anterosuperior region.
