Utku Kandemir
University of California, San Francisco
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Spine | 2005
Akin Cil; Muharrem Yazici; Akin Uzumcugil; Utku Kandemir; Ahmet Alanay; Yasemin Alanay; R Emre Acaroglu; Adil Surat
Study Design. Cross-sectional. Objectives. The purpose of this study is to describe the normative data of the sagittal plane on pediatric age population, and to document the evolution of sagittal alignment with growth. Summary of Background Data. Having normative data about the sagittal plane is an integral part in the planning of the three-dimensional reconstruction of the spine. Segmental sagittal plane analysis on adults has been studied thoroughly; however, there are inadequate data on children. Methods. A total of 151 children (72 girls, 79 boys) without musculoskeletal abnormality between the ages of 3 to 15 years were studied with the 36-inch standing lateral radiograph with the arms flexed at 30°. There were a minimum of 10 children, at least 4 of them from one sex, in each age group. Variables measured on the radiograms were as follows: segmental angulations from T1–T2 to L5–S1, angles of global kyphosis (T1–T12) and lordosis (L1–S1), segmental angulations of T2–T5, T10–T12, T10–L2, and L4–S1 levels, T1 and L1 offsets in millimeters, location of thoracic and lumbar apexes, and spinopelvic alignment measurements (angles of alpha and beta, sagittal vertebral axis, and sacropelvic translation). For statistical analysis, the children were grouped in terms of ages: Group I (3–6 years of age), Group II (7–9 years of age), Group III (10–12 years of age), and Group IV (13–15 years of age). Results. One-way analysis of variance showed significant differences between the following parameters among groups: segmental angulations of T1–T2 (P = 0.015), T10–L2 (P = 0.014), L4–S1 (P = 0.001), global kyphosis angle (P = 0.005), global lordosis angle (P = 0.000), thoracic apex (P = 0.007), T1 offset (P = 0.000), sagittal vertebral axis (P = 0.004), and beta angle (P = 0.000). As sagittal vertebral axis increases, there is found to be a higher L1 offset and lower thoracic apex, both of which result in leaning forward. With growing, total thoracic kyphosis and total lumbar lordosis particularly due to lower 2 motion segments were found to be increased, while thoracic apex moved upwards, T1 offset increased, and L1 offset decreased. Older children stood with a more negative SVA, and sacral inclination increased. Conclusion. Sagittal spinal alignment is found to be changing as a child grows. There is a statistically significant difference among different age groups, especially at cervicothoracic, thoracolumbar, and lumbosacral junc-tions. The position of the sacrum (inclination and translation), and spatial orientation, as well as the global magnitude of thoracic kyphosis, and lumbar lordosis changes with growth. These findings should be taken into consideration for the young patients who require spinal instrumentation. The question “whether sagittal alignment should be restored according to the normative data for the child’s age or to the normative data for the adulthood” remains to be answered.
Journal of Orthopaedic Trauma | 2008
Utku Kandemir; Amir Matityahu; Rohan Desai; Christian M. Puttlitz
Objectives: The purpose of this study was to compare the fixation afforded by a dorsal nonlocking plate with a volar locking plate in a fracture model simulating an extra-articular distal radius fracture with dorsal comminution (OTA [Orthopaedic Trauma Association] type 23-A3.2). Methods: In 10 matched pairs of fresh-frozen cadaveric arms, a comminuted extra-articular dorsally unstable distal radius fracture (OTA type 23-A3.2) was created. The fractures were fixed with either dorsally placed nonlocking T-plate or volarly placed locking plate within matched pairs. The precycling stiffness with axial and torsional loading of the specimens was determined. The specimens were then loaded axially for 5000 cycles, and postcycling axial and torsional stiffness and load to failure were determined. Results: The mean axial and torsional stiffness before and after cyclic loading of fractures stabilized with dorsal nonlocking plate was not significantly different than fractures fixed with volar locking plate. Although the mean load to failure was greater for the volar locking plate group than dorsal nonlocking plate group, the difference was not significant. Conclusions: This study suggests that the fixation obtained with volar locking plates is as stable as fixation with a dorsal plate in acute healing period and can withstand the functional demands of the immediate postoperative period in dorsally comminuted unstable extra-articular distal radius fractures. Elimination of dorsal tendinopathy by using volar locking plates may lead to fewer long-term complications. Locking plates provided better stability in specimens with osteoporosis.
Journal of Pediatric Orthopaedics | 2004
D. Hakan Ucar; Z. Ugur Isiklar; Carl L. Stanitski; Utku Kandemir; Yucel Tumer
Forty-four developmentally dislocated hips occurring in 30 patients with an average age at initial surgery of 10.7 (range 2–19) months underwent medial open reduction by Ferguson’s approach. All patients were skeletally mature at most recent evaluation. Mean follow-up was 19.8 (range 13–27.5) years. No redislocation or sub-luxation occurred. Additional surgery was required in 11 hips (25%). Avascular necrosis was detected in nine hips (20%). The acetabular index was decreased and the center-edge angle was increased during follow-up. Excellent or good outcome (Severin group 1 or 2) was observed in 79% of the hips at skeletal maturity. At the most recent evaluation, all but two patients had the highest score on the Iowa Hip Rating. The authors conclude that open reduction through the medial approach is effective in developmental dislocation of the hip. Follow-up until skeletal maturity is necessary for an accurate assessment of treatment.
Journal of Pediatric Orthopaedics B | 2004
Uçar Dh; Işiklar Zu; Utku Kandemir; Yucel Tumer
Successful treatment of developmental dysplasia of the hip (DDH) is associated with early diagnosis and appropriate treatment. In this prospective study, the results of the treatment with Pavlik harness followed by an abduction brace in patients with severe DDH were presented. Twenty-two hips of 18 patients with a mean age of 14.8±5.9 weeks (range, 6–26) when diagnosed were followed for an average of 24.2±10.8 months (range, 10–46). The hips were staged according to the classification of Graf with ultrasonography and Pavlik harness was instituted as the first line of treatment in all hips. If there was no improvement of ultrasonographic stage at the third week follow-up the harness treatment was discontinued. After the infant became too large for Pavlik harness an abduction brace was used. In all but one hip the treatment was successful (95.4%). In two hips type I avascular necrosis was noted. Of the dislocated hips 90% were reduced. The Pavlik harness is a safe and effective method of treatment of severe DDH in infancy if potential pitfalls are avoided.
Journal of Pediatric Orthopaedics | 2005
Umit S. Aykut; Muharrem Yazici; Utku Kandemir; Gokhan Gedikoglu; M. Cemalettin Aksoy; Akin Cil; Adil Surat
The purpose of this study was to investigate the effect of temporary hemiepiphyseal stapling on the bone geometry and proliferative activity of the physis in immature rabbits. Proximal medial epiphyseal stapling of the right tibia was performed in 46 6-week-old New Zealand white rabbits. The rabbits were assigned randomly into two groups. In group 1, the staples were inserted extraperiosteally and the rabbits were killed at the end of 3 weeks. In group 2, the staples were fixed subperiosteally (group IIA) or extraperiosteally (group IIB), the staples were removed at the end of 3 weeks, and the rabbits were killed at the end of 6 weeks. The articular line-diaphysis angle (ALDA) was significantly increased with 3 weeks of stapling. After the removal of staples, while ALDA continued to worsen in group IIA, it improved in group IIB. Bone was observed to bridge the physis in group IIA. However, the proliferative activity of the physis continued. Temporary hemiepiphyseal stapling is a safe and effective method for control of physeal growth of long bones before skeletal maturity. However, it is of paramount importance not to disturb the periosteum during stapling.
Journal of Arthroplasty | 2014
Carol Lin; Steven K. Takemoto; Utku Kandemir; Alfred C. Kuo
We hypothesized that infection rates following total joint arthroplasty (TJA) in those with the human immunodeficiency virus (HIV) without hemophilia or drug use would be similar to rates in HIV-negative patients. Records at an urban HIV referral hospital were searched for patients who underwent primary total hip and knee arthroplasty from 2003 to 2010. The primary outcome was revision for infection. 372 HIV-negative and 22 HIV-positive TJA patients met inclusion criteria. The HIV-positive group had more deep infections than the HIV-negative group (9.1% v 2.2%, P=0.102). There were no infections in those with AIDS-defining CD4 counts. Those with HIV may have a higher risk of developing a deep infection. A low CD4 count is not an absolute contraindication to TJA in HIV positive patients.
Clinical Orthopaedics and Related Research | 2013
Amir Matityahu; Meir Marmor; Joshua Elson; Corey Lieber; Gregory Rogalski; Cindy Lin; Tigist Belaye; Theodore Miclau; Utku Kandemir
BackgroundHemodynamically unstable patients with a pelvic fracture and arterial pelvic bleeding frequently are treated with pelvic angiographic embolization (PAE). PAE is reported to be a safe and effective method of controlling hemorrhage. However, the loss of blood supply and subsequent ischemia from embolization may lead to adverse consequences.Objectives/purposesWe sought to determine (1) the frequency and types of complications observed after PAE; (2) the mortality after PAE; and (3) the clinical factors associated with complications and mortality after PAE.MethodsWe conducted a retrospective case series descriptive study at a Level I trauma center. Using our institution’s trauma registry, we isolated patients with pelvic fractures treated with PAE admitted between June 1999 and December 2007. Complications attributed to PAE occurring in the initial hospital stay were recorded. We identified 98 patients with pelvic fractures treated by PAE with an average hospital stay of 25.3 days.ResultsThe complication rate was 11% and included six patients with gluteal muscle necrosis (6%), five with surgical wound breakdown (5%), four deep infections (4%), one superficial infection, two patients with of impotence (2%), and one with bladder necrosis. The mortality rate in the PAE group reached 20%. Bilateral embolization was performed in 100% of the patients with complications. Nonselective embolization was performed in 81% of patients with complications. All of the patients with gluteal necrosis had bilateral nonselective embolization.ConclusionsBilateral or nonselective PAE is associated with significant complications during the initial hospital stay. The value of PAE should be weighed against its possible adverse consequences. Selective unilateral arterial embolization should be considered whenever possible.Level of EvidenceLevel IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
Journal of Bone and Joint Surgery, American Volume | 2002
Utku Kandemir; Muharrem Yazici; A. Mumtaz Alpaslan; Adil Surat
Background: Although there have been numerous studies on the treatment of developmental dysplasia of the hip, few have focused on its natural history into adulthood. We observed valgus deformity of the knee in a group of adult patients with developmental dysplasia of the hip. To the best of our knowledge, there has been no detailed study of that condition.The purpose of this study was to investigate structural changes of the knee in patients with neglected developmental dysplasia of the hip.Methods: Thirty-four adult patients with neglected developmental dysplasia of the hip and ten healthy adults were evaluated. The lower extremities were grouped according to the severity of the dysplasia. The morphology of the knees was evaluated with radiographic measurements, and the groups were compared.Results: Compared with the control group, the patients with severe developmental dysplasia of the hip had significant valgus deformity of the knee. This finding was associated with an increased vertical dimension of the medial femoral condyle, which led to a valgus inclination of the distal femoral articular surface. Although the femoral sulcus was shallower in the patients with developmental dysplasia of the hip, patellofemoral congruency was not deranged.Conclusions: The pathologic condition of the hip joint in patients with developmental dysplasia of the hip results in developmental changes in the osseous anatomy of the knee joint, with the development of a valgus deformity of the lower extremity. If any surgical intervention is planned in a patient with developmental dysplasia of the hip, the whole lower extremity should be carefully analyzed, with special attention to the morphology of the knee, to avoid creating problems of malalignment.
Journal of Pediatric Orthopaedics B | 2006
Işiklar Zu; Utku Kandemir; Uçar Dh; Yucel Tumer
It is controversial to perform bone surgery at the time of open reduction in developmental dislocation of the hip in children 12–18 months old. The purpose of this study is to investigate whether concomitant bone surgery is necessary in patients treated with medial open reduction in this age range. Patients that were under 12 months of age at the time of open reduction were compared with patients that were 12–18 months old. Forty-four hips of 30 patients treated with open reduction through Fergusons medial approach have been included in the study. Mean follow-up was 19.6 years (13–27.5). Age at the time of open reduction was less than 12 months in 21 hips (group A) and 12 months or more in 23 hips (group B). There was no significant difference between two groups concerning avascular necrosis or unsatisfactory radiological outcome (Severins groups III and IV). A higher rate of secondary bone surgery was necessary in group B than in group A. Although secondary bone surgery is needed at a higher frequency in children 12–18 months old, the radiological outcome is not significantly different for patients younger than 12 months. Therefore, the recommendation of concomitant bone surgery on a routine basis during open reduction in developmental dislocation of the hip in children 12–18 months old is debatable.
Arthroscopy | 2011
Thomas Chu; Erik McDonald; Michael Tufaga; Utku Kandemir; Jenni M. Buckley; C. Benjamin Ma
PURPOSE The purpose of this study was to compare the biomechanical performance of a completely knotless double-row repair system (SutureCross Knotless Anatomic Fixation System; KFx Medical, Carlsbad, CA) with 2 commonly used hybrid double-row repair (medial knot-tying, lateral knotless) systems (Bio-Corkscrew/PushLock [Arthrex, Naples, FL] and Spiralok/Versalok [DePuy Mitek, Raynham, MA]). METHODS Fourteen pairs of fresh-frozen cadaveric shoulders were harvested, the supraspinatus tendons were isolated, and full-thickness supraspinatus tears were created. One of each pair was repaired with the completely knotless system, and the contralateral side was repaired with either of the hybrid systems. The repairs were then subjected to cyclic loading followed by load to failure. Conditioning elongation, peak-to-peak elongation, ultimate load, and mechanism of failure were recorded and compared by use of paired t tests. Seven additional shoulders were tested to determine the effect of refrigeration storage on the completely knotless system by use of the same mechanical testing protocol. RESULTS For the completely knotless repair group, 11 of 14 paired specimens failed during the cyclic loading period. Only 1 of 14 hybrid repair systems had failures during cyclic loading, and both hybrid repair systems had statistically lower conditioning elongation than the completely knotless repair group. The mean ultimate load of the SutureCross group was 166 ± 87 N, which was significantly lower than that in the Corkscrew/PushLock (310 ± 82 N) and Spiralok/Versalok (337 ± 44 N) groups. There was an effect of refrigeration storage on the peak-to-peak elongation and stiffness of the SutureCross group; however, there was no difference in ultimate tensile load or conditioning elongation. CONCLUSIONS The completely knotless repair system has lower time-zero biomechanical properties than the other 2 hybrid systems. CLINICAL RELEVANCE The SutureCross system has lower time-zero biomechanical properties when compared with other hybrid repair systems. Clinical outcome studies are needed to determine the significance.