Aortic dissection is a life-threatening disease that consists in the development of a tear in the wall of the aorta. The initial tear propagates as a discontinuity leading to separation within the aortic wall, which can result in the creation of a so-called false lumen. A fatal threat occurs if the rupture extends through the whole thickness of the aortic wall, as blood may then leak. It is generally accepted that the dissection, which can sometime extend along the entire length of the aorta, propagates via a delamination mechanism. The aim of the present paper is to provide experimentally validated parameters of a mathematical model for the description of the wall's cohesion. A model of the peeling experiment was built in Abaqus. The delamination interface was described by a piecewise linear traction-separation law. The bulk behavior of the aorta was assumed to be nonlinearly elastic, anisotropic, and incompressible. Our simulations resulted in estimates of the material parameters for the traction-separation law of the human descending thoracic aorta, which were obtained by minimizing the differences between the FEM predictions and the delamination force given by the regression of the peeling experiments. The results show that the stress at damage initiation, Tc, should be understood as an age-dependent quantity, and under the assumptions of our model this dependence can be expressed by linear regression as Tc = - 13.03·10-4·Age + 0.2485 if the crack front advances in the axial direction, and Tc = - 7.58·10-4·Age + 0.1897 if the crack front advances in the direction of the aortic circumference (Tc [MPa], Age [years]). Other model parameters were the stiffness K and the separation at failure, δf-δc (K = 0.5 MPa/mm, δf-δc = 0.1 mm). The material parameters provided by our study can be used in numerical simulations of the biomechanics of dissection propagation through the aorta especially when age-associated phenomena are studied.
- Keywords
- Aging, Cohesive model, Crack, Damage, Finite elements method, Fracture,
- MeSH
- Finite Element Analysis MeSH
- Aorta, Thoracic * physiology MeSH
- Biomechanical Phenomena MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Stress, Mechanical MeSH
- Models, Cardiovascular MeSH
- Computer Simulation MeSH
- Aged MeSH
- Aging physiology MeSH
- Traction MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Aged MeSH
- Publication type
- Journal Article MeSH
BACKGROUND: Central incisor impaction is a rare condition with potentially severe clinical and psychological implications for the patient. Treatment techniques vary according to the pretreatment situation and individual factors. The aim of this study was to compare the esthetic outcomes and treatment times between two different approaches. MATERIALS AND METHODS: In this retrospective study, thirty-one consecutive patients (13 boys, 18 girls; average age 9.5 ± 2.3 years) with a total of 34 impacted permanent upper central incisors were included in the study. Patients were divided into two groups according to method of treatment. Group A comprised patients in whom spontaneous eruption occurred after space opening (n = 12), and Group B comprised patients in whom teeth showed no eruption and required treatment with a modified closed eruption method with palatally oriented traction (n = 19). Treatment time and esthetic outcomes were assessed and compared between groups. RESULTS: The mean treatment time was 22.0 ± 6.7 months, and all teeth were successfully aligned. No statistically significant difference in average treatment time was found between groups in baseline characteristics (p > 0.05). The amount of attached gingiva was significantly smaller when compared to contralateral reference teeth in the closed eruption group (Group B; p = 0.03). However, no difference in amount of attached gingiva was found between both groups (p = 0.26). Additionally, no difference in the clinical crown length was found between groups (p = 0.27). CONCLUSION: The closed eruption method with palatal traction directed at the peak of the alveolar crest provided results comparable to the physiologic tooth eruption.
- Keywords
- Active traction, Attached gingiva, Central incisor, Closed eruption, Spontaneous eruption, Tooth impaction,
- MeSH
- Child MeSH
- Humans MeSH
- Maxilla MeSH
- Tooth Eruption * MeSH
- Retrospective Studies MeSH
- Incisor MeSH
- Traction MeSH
- Tooth, Impacted * therapy MeSH
- Check Tag
- Child MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
Traction force microscopy (TFM) has emerged as a versatile technique for the measurement of single-cell-generated forces. TFM has gained wide use among mechanobiology laboratories, and several variants of the original methodology have been proposed. However, issues related to the experimental setup and, most importantly, data analysis of cell traction datasets may restrain the adoption of TFM by a wider community. In this review, we summarize the state of the art in TFM-related research, with a focus on the analytical methods underlying data analysis. We aim to provide the reader with a friendly compendium underlying the potential of TFM and emphasizing the methodological framework required for a thorough understanding of experimental data. We also compile a list of data analytics tools freely available to the scientific community for the furtherance of knowledge on this powerful technique.
- Keywords
- biophysics, cell adhesion, cytoskeleton, focal adhesion, mechanosignaling, mechanotransduction, traction force microscopy,
- MeSH
- Biophysics MeSH
- Cell Adhesion MeSH
- Microscopy, Atomic Force methods MeSH
- Traction * MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
PURPOSE OF THE STUDY The purpose of the retrospective study was to analyse the success rate and safety of overhead traction in treating decentered hip joints. In patients treated strictly non-operatively, i.e. with no open reduction and no operative management of residual dysplasia performed, acetabular development was assessed once they have reached the skeletal maturity. MATERIAL AND METHODS The restrospective study included a total of 40 patients treated by overhead traction in the period 1999-2002 for developmental dysplasia of the hip (ultrasound classes III.A, III.B, IV according to Graf classification). The study group consisted of 35 girls and 5 boys. 10 patients were affected bilaterally. The two-phase traction was applied during the hospital stay and concluded by arthrography of the treated hip joint under general anaesthesia to confirm its concentric reduction and stability within the safe zone. To allow healing, bilateral plaster hip spica cast was applied for 6 weeks, followed by Pavlik harness. The Salter diagnostic criteria were used for avascular necrosis. The acetabular development in non-operatively treated patients was assessed after reaching skeletal maturity according to the Severin criteria. The radiographic parameters (center-edge angle of Wiberg, Sharp angle, Tönnis angle, acetabular coverage of the femoral head, grade of osteoarthritis according to Tönnis classification) were statistically compared with the control group of 18 healthy contralateral hip joints. RESULTS By overhead traction the closed reduction of 43 hips (86%) was successfully achieved. In the group of hips with successful closed reduction, avascular necrosis of the femoral head developed in 1 case (2.3%). In preschool age, surgical correction of the residual acetabular dysplasia or subluxation was performed in 7 hip joints (16%) in the group of successful closed reductions. According to the Severin criteria for the evaluation of radiographic results, the findings were favourable (Severin Ia, Ib) after reaching the skeletal maturity in 29 of 43 (67%) hip joints, in which closed reduction was originally successfully achieved. No statistically significant difference in the studied radiographic parameters was found between the group of treated hip joints and the control group. DISCUSSION Despite the general consensus regarding the beneficial effects of early diagnosis of developmental dysplasia of the hip in the form of better treatment outcomes and reduced risk of complications in the world literature, the authors of individual studies do not agree as to the used treatment method, timing and duration of treatment. Neither they agree as regards the importance of traction therapy in decentered hip joints. Our study brings information primarily on the acetabular development in patients treated by traction, commenced early, namely before the age of 6 months. CONCLUSIONS Based on our experience, the overhead traction is an efficient treatment option in managing decentered hip joints (ultrasound types III.A, III.B, IV according to Graf). It is a safe method provided the safe zone principles are adhered to during the traction treatment as such as well as during the retention phase with the plaster hip spica applied. Development of the treated hip joint shall be regularly followed up until the skeletal maturity is reached. Key words: developmental dysplasia of the hip, closed reduction, overhead traction.
- MeSH
- Infant MeSH
- Hip Joint MeSH
- Humans MeSH
- Child, Preschool MeSH
- Retrospective Studies MeSH
- Traction MeSH
- Treatment Outcome MeSH
- Developmental Dysplasia of the Hip * MeSH
- Hip Dislocation, Congenital * diagnostic imaging therapy MeSH
- Check Tag
- Infant MeSH
- Humans MeSH
- Male MeSH
- Child, Preschool MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
PURPOSE OF THE STUDY The paper aimed to evaluate the long-term outcomes of the treatment of diaphyseal femur fractures in children treated with Bryant's vertical traction. Moreover, we also assessed the size of overgrowth in the injured femur. MATERIAL AND METHODS The study included 23 patients with 23 femoral shaft fractures treated with Bryant's vertical traction at our department in 2009-2014. The following parameters were assessed: sex, ïnjured side, weight, age, mechanism of injury, potential abuse, type of fracture, duration of traction, and total length of hospital stay. The healing time of the fracture was the same as the duration of traction. Also assessed was the size of femoral shortening after the removal of traction, the presence of skin complications in the course of treatment and potential development of compartment syndrome. At the mean follow-up of 47.8 months (range 22-85 months) from the date of injury the patients were evaluated clinically and radiologically for: length of limbs, presence of rotational deformity, range of motion of knee and hip joints, potential pain or limping, potential scoliosis of the spine and presence of scars after traction. Finally, through a questionnaire we learned about the opinions of parents as to the treatment method and about the possibility of home traction. RESULTS All the fractures healed. There was a total of 17 injured boys and 6 injured girls. Whereas 12 patients sustained a fracture of the left femur, 11 patients sustained a fracture of the right femur. The mean weight of patients at the time of injury was 13.9 kg (range 5-20 kg). The mean age at the time of traction was 30.8 months (range 1-70 months). The injury most frequently occurred from various falls, altogether in 15 cases (65.2%). Traffic accidents were registered as the cause of injury in 3 cases (13%). No abuse was confirmed. The average duration of traction was 19.8 days (range 8-26 days). The total length of hospital stay took on average 23.6 days (range 9-33 days). Skin excoriation and bullae due to irritation by the traction occurred in 21 children (91.3% cases). All the bullae healed, in 4 (17.4%) patients minor scars of 1x1 cm in size were formed around ankles. Not a single patient developed the compartment syndrome. The average femoral shortening after the removal of traction was 0.8 cm (range 0-2.3 cm). The follow-up examination, performed on average 47.8 months (range 22-85 months) from the date of injury revealed the average discrepancy of spinomalleolar distances in both the lower limps of 0 cm (range -1 to 1 cm). Radiographically measured lengths of both the femurs showed the average difference of 0 cm (range -1.4 to 0.9 cm). The resulting average overgrowth of injured femur was 0.9 cm (range 0.1 to 3.2 cm). Scoliosis of the spine was not reported in any of the patients. In 3 patients femur alignment demonstrated rotation, namely an external rotation of 10° in all the cases. All the children demonstrated full hip and knee joint mobility, identical to the uninjured side. After a heavy load one patient reported pain in the thigh and one walked with limp. The other patients showed no problems whatsoever. Treatment with the use of Bryant's traction was well tolerated by parents. Altogether 15 parents (65.2%) would opt for the same treatment method in case of a recurrent injury. The home traction option would be welcomed by 17 parents (73.9%). DISCUSSION The treatment by Bryant's vertical traction is condemned in Anglo-Saxon countries due to the risk for developing compartment syndrome, described in earlier studies. Neither our cohort, nor more recent studies reported the occurrence of compartment syndrome. The most frequent complication faced in our study was the skin complications underneath the traction, namely in a total of 91.3% of patients. In the literature, the other authors only make references to bullae occurrence, but do not provide any further specifications. Overgrowth after femoral shaft fractures is a very well described phenomenon. The size of femoral overgrowth described in our study was similar to that referred to in the available literature. A method frequently used abroad is the so-called home traction. This method, however, has so far failed to take root in our country, even though this therapeutic technique would be appreciated by parents. CONCLUSIONS The treatment of femoral shaft fractures by Bryant's vertical traction, in children up to the weight of 15 kg, is a simple and safe method with excellent functional outcomes and minimum serious complications. When treating the children with the body weight more than 15 kg, the risk of bullae formation increases, therefore in this weight category treatment shall be decided upon on a case by case basis. The resulting average overgrowth of injured femur was 0.9 cm which corresponds with the findings of other authors. The treatment method using the Bryant's traction is well tolerated by parents, even though most of them would welcome the option of home traction. Key words: traction, femur fracture, overgrowth, children.
- MeSH
- Length of Stay MeSH
- Child MeSH
- Accidents, Traffic MeSH
- Femoral Fractures therapy MeSH
- Infant MeSH
- Humans MeSH
- Infant, Newborn MeSH
- Child, Preschool MeSH
- Traction methods MeSH
- Treatment Outcome MeSH
- Check Tag
- Child MeSH
- Infant MeSH
- Humans MeSH
- Male MeSH
- Infant, Newborn MeSH
- Child, Preschool MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
A rare case of a middle-third clavicle fracture concurrent with ipsilateral acromioclavicular dislocation in a 46-year-old women who had fallen off her bicycle is presented. The clavicular fracture was managed by locking plate osteosynthesis. The acromioclavicular joint was stabilised by traction osteorrhaphy that was removed at 7 weeks after the procedure. Both the radiographic and clinical outcomes were very good. The epidemiology, aetiology, diagnosis and therapy of this injury are discussed.
- MeSH
- Acromioclavicular Joint diagnostic imaging injuries MeSH
- Fractures, Bone diagnostic imaging surgery MeSH
- Clavicle diagnostic imaging injuries MeSH
- Bone Plates MeSH
- Middle Aged MeSH
- Humans MeSH
- Shoulder Dislocation diagnostic imaging surgery MeSH
- Radiography MeSH
- Traction MeSH
- Accidental Falls MeSH
- Fracture Fixation, Internal MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
PURPOSE OF THE STUDY: Developmental dysplasia of the hip (DDH) is a disorder affecting the development of the acetabulum, proximal femur and joint capsule. The objective of this study was to analyse the results of closed reduction by overhead traction in subluxated and dislocated hips. MATERIAL AND METHODS: In the period from 2002 to 2007, a total of 109 patients (124 hips) were treated by overhead traction. The indication criteria included adductor contracture and misalignment of the hip joint assessed as classes III A, III B or IV according to the Graf ultrasonographic classification. There were 96 (88 %) girls and 13 (12 %) boys. The left side was more frequently affected, at a ratio of 83 to 41, and bilateral DDH was found in 15 patients. Teratologic dislocations were not included in the study. The patients were divided into two groups according to age and the place of primary diagnosis. The children primarily diagnosed at our hospital Na Bulovce where placed in group 1, the patients diagnosed outside our hospital fell in group 2. The average age at the beginning of treatment was 2.2 months in the first group and 6 months in the second group. Our method of overhead traction consists of two phases. Horizontal traction is applied for two weeks in phase 1; the hips are then flexed beyond 90 degrees and gradually abducted for another 4 weeks in phase 2.The outcome of traction is examined by arthrography and a spica cast is applied in the safe zone.We observed the relation between the Graf classification and arthrograpy. The outcome of closed reduction was compared between the groups and the development of avascular necrosis was observed. The hips treated by open reduction were assessed in a different study. RESULTS The efficiency of closed reduction was 84 % in group 1 and 60 % in group 2 in which also two cases of recurrent dislocation were found. No significant differences between the Graf classification and the final arthrographic findings were recorded in either group (p ≥ 0.05). Avascular necrosis as defined by the Salter criteria was not diagnosed. DISCUSSION: Early reduction is essential to ensure normal development of the hip joint. Overhead traction therapy for misalignment of the hip joint is a safe method reducing damage to the femoral head. Its principle lies in gradual distraction of the contracted muscles and joint capsule with a concomitant change in traction direction in order to achieve a reduction manoeuvre without placing increased stress on the femoral head. CONCLUSIONS: Overhead traction is the method of choice for management of Graf's class III A, III B and IV hips. For the efficiency of treatment, an early diagnosis and a correct indication are essential. To avoid complications such as avascular necrosis, it is necessary to observe the principle of a safe zone.
PURPOSE OF THE STUDY: Conservative therapy is the method of choice for treating femoral fractures in younger children all over the world. At the Department of Orthopedic Surgery of the Second Faculty of Medicine, Charles University in Prague, this approach has had a long tradition and has only partly been replaced by other, more recent methods. It is not always necessary to abandon well-established and reliable techniques because of new achievements and this is demonstrated by the results of our study. MATERIAL: In a period of 22 years, 112 boys and 97 girls were treated by Bryant's traction and 62 boys and 46 girls by Weber's traction. The former was used in children younger than 5 years, weighing less than 20 kg. The latter was applied in patients between 5 and 10 years of age whose body mass was between 20 to 35 kg. METHODS: Bryant's traction, used in the younger age category, offered the advantage of easy application without total anesthesia. Both legs were suspended in an apparatus that keeps the patient's pelvis slightly elevated above the bed level. Counter traction was provided by the weight of the suspended pelvis. In Weber's traction, used in children aged 5 to 10 years, a Kirschner's wire was inserted in the distal metaphysis of each femur in the frontal plane. The ends of each wire were attached to a metal U-shaped spreader. This apparatus holds the legs at right angles both in the knees and hips. Each patient was examined by X-ray at 1 week to check the correction of displacement and at 3 weeks to check callus development. All the patients were immobilized in a plaster cast spica for a period of 6 to 8 weeks after injury and each child was also shortly hospitalized for cast removal and early physical therapy. RESULTS: Fractures in the middle of the diaphysis with an oblique fracture line were most frequent. These and long spiral fractures responded well to these two methods in almost all cases. In transverse fractures, which are less common, when an angular dislocation persisted it was tolerated owing to the subsequent remodelation. The most serious complication was a shortening of the leg involved, which often occurred with the use of Bryant's traction. The shortening was found in 80% of the patients shortly after the fracture had healed. A low body mass of the child was generally responsible for failure to stretch the femur to its full length. In children treated by Weber's traction, the shortening was observed in 55% immediately after fracture healing. On examination at 1 and 3 weeks, its presence was markedly lower, occurring in 25% and 17% of the children, respectively. Lengthening was found only occasionally on examination in adolescence or adulthood, but this may have been due to other causes. Excessive movement of the child in bed, usually when the parents came to visit, sometimes interfered with good correction of the displacement. DISCUSSION: Bryant's traction was used in our department for conservative treatment even in very young children. The plaster cast spica was applied primarily to non-displaced fractures. Pavlík's harness, recommended by Rockwood and Stannard, was used in pediatric injuries only occasionally. When conservative treatment was indicated in older children, Weber's traction was applied. The Göteborg traction described by Havránek was not used. The shortening of the leg treated was the most frequent complication, but our results were not in agreement with the data reported by Stahelim, who described a greater and more frequent shortening in children older than our patients. In our study, younger children suffered from leg shortening more often, as was also reported by Náhoda and Stryhal. The subsequent lengthening was found only occasionally; the average values of 2.6 cm and 2.3 cm in younger and older children, respectively, as reported by Náhoda and Stryhal, were not recorded. When lengthening was observed, its value was always lower. A 30 degrees rotational deviation, observed by Verbeek in one third of his patients, was not seen in our children. Pseudoarthrosis or infection were absent in our population and a literature search showed that, when treated conservatively, femoral fractures were not associated with these complications. CONCLUSIONS: Well-established methods of conservative treatment of femoral fractures in children were evaluated with the objective to advocate their importance for today's orthopedic surgery. Although the children treated by these methods are confined to bed for a longer period than when more recent techniques are used, they may avoid many of the complications that accompany these new approaches.
- MeSH
- Child MeSH
- Femoral Fractures therapy MeSH
- Humans MeSH
- Child, Preschool MeSH
- Traction MeSH
- Check Tag
- Child MeSH
- Humans MeSH
- Male MeSH
- Child, Preschool MeSH
- Female MeSH
- Publication type
- English Abstract MeSH
- Journal Article MeSH
The purpose of this study is to evaluate the effectiveness of the use of traction in achieving closed reduction of a dislocated hip. We evaluated 38 hips in 29 consecutive patients who had been treated at our department between January 1999 and December 2001. There were 26 girls and 3 boys and the average age was 8 weeks. The minimal duration of follow-ups was 12 months after closed reduction. We achieved 32 concentricaly reduced hips, the barriers to the concentric reduction were demonstrated by arthrography in 5 hips an 1 hip redislocated after removal of the spica cast. Avascular necrosis of the femoral head developed in no conservatively treated hip. The traction reduction method is preferred at our department because of high rate of success without damaging the femoral head.
- MeSH
- Infant MeSH
- Humans MeSH
- Infant, Newborn MeSH
- Traction * MeSH
- Hip Dislocation, Congenital therapy MeSH
- Check Tag
- Infant MeSH
- Humans MeSH
- Male MeSH
- Infant, Newborn MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
This paper evaluates the results of conservative treatment for developmental dysplasia of the hip after an average follow-up of 3 years in 69 patients and 99 hips: 31 bilateral, 23 left side, and 14 right. They were treated at the Al-Razi Hospital, Kuwait, between January 1995 and December 1996. There were 59 girls and 10 boys aged between 5 months and 24 months (average age 12 months). The treatment consisted of traction for 1 or 2 weeks, followed by manipulation in 36 hips and manipulation with adductor longus tenotomy in 45 hips and with adductor longus and psoas tenotomy in 18 hips. Avascular necrosis of the femoral head developed in 16 hips (16%): 14 hips on the affected side and 2 hips on the unaffected side. Persistent acetabular dysplasia was present in 13 hips, subluxation in 9 hips and dislocation in 13 hips. Open reduction was later required in 5 hips, open reduction and innominate osteotomy in 8 hips, and hip extracapsular innominate osteotomy in 1 hip. The results were evaluated according to the age groups with highest rate of complications after the age of 15 months. The treatment protocol was changed to limit conservative treatment until the age of 14 months.
