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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 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 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 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.
