trans-Di-aqua-tetra-kis-(tetra-hydro-furan-κO)iron(II) µ-carbonyl-tetra-deca-carbonyl-tetra-chlorido-µ-di-methyl-silanediolato-tetra-galliumtetra-iron(7 Ga-Fe)(Fe-Fe) tetra-hydro-furan tetrasolvate.

The title compound, [Fe(C4H8O)4(H2O)2][Fe4Ga4(C2H6O2Si)Cl4(CO)15]·4C4H8O, consists of an iron(II) cation octa-hedrally coordinated by two water mol-ecules (trans) with four tetra-hydro-furans (THF) at equatorial sites. Two additional THF mol-ecules are hydrogen bonded to each of the water mol-ecules. The dianion of the title compound is an organometallic butterfly complex with a dimethyl siloxane core and two iron-gallium fragments. The lengths of the iron to gallium metal-metal bonds range from 2.3875 (6) to 2.4912 (6) Å.

Conservative Binary Dynamics at Order α

We compute the potential-photon contributions to the classical relativistic scattering angle of two charged nonspinning bodies in electrodynamics through fifth order in the coupling. We use the scattering amplitudes framework, effective field theory, and multiloop integration techniques based on integration by parts and differential equations. At fifth order, the result is expressed in terms of cyclotomic polylogarithms. Our calculation demonstrates the feasibility of the corresponding calculations in general relativity, including the evaluation of the encountered four-loop integrals.

Range of international surgical strategies for adolescent idiopathic scoliosis: Evaluation of a multi-center survey.

Background: Surgical treatment of adolescent idiopathic scoliosis (AIS) is very complex and modern instrumentation techniques offer multiple possibilities. Despite numerous publications, there is no clear consensus on the optimal strategy for the correction of scoliotic deformities. The goal of this study was to summarize the current surgical strategies for specific AIS cases within various countries. Method: Thirty-two experienced scoliosis surgeons from 15 countries were asked to plan surgeries on 12 representative AIS cases. All AIS cases had an indication for surgery. A questionnaire was provided to document surgical planning. The surgeons were provided with the patients' age and sex, together with radiographs in the lateral and sagittal planes during upright standing and in lateral bending to the left and right, as well as with clinical images. The angles of the main spinal curvatures were specified in the questionnaire. The surgeons were asked to specify their preferred classification system, their surgical approach, the planned fusion length, the type of implants, the rod type, and the resection steps. The data were analyzed with respect to the inter-rater variability, which was quantified using the Fleiss-Kappa Method. Results: There was a good agreement (k = 0.61) between the surgeons in choosing the Lenke curve type, and a moderate agreement for the lumbar (0.41) and sagittal (0.56) modifiers. The most frequently planned resection procedure was complete facetectomy (67%). The posterior approach was the most commonly (91%) selected strategy to treat AIS. Anterior approaches were chosen most for Lenke 5 type with a rate of 20%. The upper instrumented vertebra (UIV) varied most for Lenke 1, 5, and 6 cases, with a vertebral level discrepancy of up to 10 levels at Lenke 6. The lowest instrumented vertebra varied most for Lenke 1 and 4 by up to five levels. Polyaxial screws were chosen most (56%), followed by monoaxial (20%) and uniplanar (19%) screws and hooks (5%). Conclusions: The results highlight the commonalities and discrepancy in the surgical treatment of AIS in between surgeons. The selected LIV and UIV can vary depending on the curve type and surgeon. Hook constructs appear to be generally replaced by transpedicular screws. The survey indicates open questions in the AIS treatment and in the understanding of scoliosis biomechanics.

Investigation of Pressure Effects in the Bimetallic Transplutonium Tetrazolate Complexes [(An(pmtz)2(H2O)3)2(µ-pmtz)]2(pmtz)2·nH2O (An3+ = Cm3+, Bk3+, and Cf3+).

Understanding the effects of pressure on actinide compounds is an integral part of safe nuclear waste storage in deep geologic repositories and provides a means of systematically altering the structure and properties. However, detailing how the effects of pressure evolve across the actinide series in the later elements is not typically undertaken because of the challenges of conducting research on these unstable isotopes. Here, a family of bimetallic actinide complexes, [(An(pmtz)2(H2O)3)2(µ-pmtz)]2(pmtz)2·nH2O (An3+ = Cm3+, Bk3+, and Cf3+, pmtz- = 5-(pyrimidyl)tetrazolate; Cm1, Bk1, and Cf1), are reported and represent the first structurally characterized bimetallic berkelium and californium compounds. The pressure response as determined from UV-vis-NIR transitions varies for Cm1, Bk1, and Cf1. The 5f → 5f transitions in Cm1 are notably more sensitive to pressure compared to those in Bk1 and Cf1 and show substantial bathochromic shifting of several 5f → 5f transitions. In the case of Bk1, an ingrowth of a metal-to-ligand charge-transfer transition occurs at elevated pressures because of the accessible Bk3+/Bk4+ couple. For Cf1, no substantial transition shifting or emergence of MLCT transitions is observed at elevated pressures because of the prohibitive energetics of the Cf3+/Cf4+ couple and reduced sensitivity of the 5f → 5f transitions to the local coordination environment because of the more contracted 5f shell versus Cm3+ and Bk3+.

Range of surgical strategies for individual adolescent idiopathic scoliosis cases: evaluation of a multi-centre survey.

PURPOSE: Surgical treatment of adolescent idiopathic scoliosis (AIS) is very complex, involves many critical decisions and modern instrumentation techniques, and offers multiple possibilities. It is known that the surgical strategy may vary strongly between surgeons for AIS cases. The goal of this study was to document, summarize, and analyse the current biomechanical relevant variabilities in the surgical treatments of individual AIS patient cases. METHODS: Eight experienced scoliosis surgeons from different hospitals were asked to plan surgeries on 12 representative patients with AIS. The surgeons were provided with radiographs during upright standing in the coronal and sagittal plane, as well as lateral bending images to the left and right. The surgeons were asked to specify the Lenke type, their surgical approach, the resection steps, the planned fusion length, and the type of implants. The data were analysed with respect to the inter-rater variability, which was quantified using the Fleiss Kappa method. RESULTS: In the selection of the surgical approach, the surgeons concurred most with Lenke curve types 2 (κ = 0.88) and 4 (κ = 0.75). The largest differences were shown at Lenke 1 (κ = 0.39) and 5 (κ = 0.32). Anterior approaches were selected in the majority of cases at Lenke types 5, with an average of 50%. The strongest deviation in fusion length was documented at Lenke curve type 6. CONCLUSION: The survey highlighted differences in the surgical strategy depending on the Lenke curve type, the direction of the surgical approach, and the surgeon. The main discrepancies between the surgeons were found for Lenke 1, 5, and 6 curves, and consistencies for Lenke 2, 3, and 4. The documented discrepancies indicate the remaining open questions in the surgical treatment and understanding of scoliosis biomechanics.

Paediatric spine injuries in the thoracic and lumbar spine-results of the German multicentre CHILDSPINE study.

BACKGROUND: Paediatric thoracolumbar spine injuries are rare, and meaningful epidemiological data are lacking. OBJECTIVES: The aim of this study was to provide epidemiological data for paediatric patients with thoracolumbar spinal trauma in Germany with a view to enhancing future decision-making in relation to the diagnostics and treatment of these patients. MATERIALS AND METHODS: A retrospective multicentre study includes patients up to 16 years of age who were suffering from thoracolumbar spine injuries who had been treated in six German spine centres between 01/2010 and 12/2016. The clinical database was analysed for patient-specific data, trauma mechanisms, level of injury, and any accompanying injuries. Diagnostic imaging and subsequent treatment were investigated. Patients were divided into three age groups for further evaluation: age group I (0-6 years), age group II (7-9 years) and age group III (10-16 years). RESULTS: A total of 153 children with 345 thoracolumbar spine injuries met the inclusion criteria. The mean age at the time of hospitalization due to the injury was 12.9 (± 3.1) years. Boys were likelier to be affected (1:1.3). In all age groups, falls and traffic accidents were the most common causes of thoracolumbar spine injuries. A total of 95 patients (62.1%) were treated conservatively, while 58 (37.9%) of the children underwent surgical treatment. Minimally invasive procedures were the most chosen procedures. Older children and adolescents were likelier to suffer from higher-grade injuries according to the AOSpine classification. The thoracolumbar junction (T11 to L2) was the most affected level along the thoracolumbar spine (n = 90). Neurological deficits were rarely seen in all age groups. Besides extremity injuries (n = 52, 30.2%), head injuries represented the most common accompanying injuries (n = 53, 30.8%). Regarding spinal injuries, most of the patients showed no evidence of complications during their hospital stay (96.7%). CONCLUSIONS: The thoracolumbar junction was more frequently affected in older children and adolescents. The majority of thoracolumbar spinal column injuries were treated conservatively. Nevertheless, 37.9% of hospitalized children had to be treated surgically, and there was an acceptable complication rate for the surgeries that were performed.

[Surgical treatment of congenital scoliosis]. / Operative Therapie der kongenitalen Skoliosen.

OBJECTIVE: Early correction of congenital scoliosis including short fusion, while minimizing both mobility restrictions and growth impairment. INDICATIONS: Congenital scoliosis with marked deformity, proven progression, significant compensatory curves, and/or impairment of trunk balance. Furthermore, in case of compression of neural structures or pain due to secondary degeneration. CONTRAINDICATIONS: No absolute contraindication. SURGICAL TECHNIQUE: Posterior approach to the apex of the deformity. In the growing spine the periosteum should only be touched at the levels where fusion is planned. Insertion of pedicle screws adjacent to the hemivertebra. The posterior elements of the hemivertebra are removed: lamina, joint facets, pedicle, transverse process. Resection of the accessory proximal rib in the thoracic spine. Following blunt dissection at the lateral and anterior surface of the hemivertebra, the body of the hemivertebra and the adjacent discs are resected. The resulting gap is closed by compression via transpedicular instrumentation thus correcting the scoliotic deformity. In case of synostosis or contralateral bar formation, the concave side of the spine is dissected and the synostosis osteomized. POSTOPERATIVE MANAGEMENT: Early mobilization on postoperative day 1. Bracing for 12 weeks depending on stability of the instrumentation. Periodic clinical and radiographic controls until the end of growth. RESULTS: Posterior hemivertebra resection with transpedicular instrumentation is considered as the standard treatment of congenital scoliosis. Correction rates of 60-80% are achieved. Cervical and lumbosacral hemivertebrae may require an additional anterior approach. In case of synostosis, bar formation, or rib synostosis, further corrective surgeries may be necessary during growth.

Pediatric cervical spine injuries-results of the German multicenter CHILDSPINE study.

OBJECTIVES: The aim of this study was to provide epidemiological data of pediatric patients suffering from cervical spinal trauma in Germany, in order to integrate these data in future decision-making processes concerning diagnosis and therapy. MATERIALS AND METHODS: Retrospective multicenter study includes all patients up to 16 years suffering from cervical spine injuries who were treated in six German spine centers between 01/2010 and 12/2016. The clinical databases were screened for specific trauma mechanism, level of injury as well as accompanying injuries. Diagnostic imaging and the chosen therapy were analyzed. Patients were divided into three age groups for further evaluation: age group I (0-6 years), age group II (7-9 years), age group III (10-16 years). RESULTS: A total of 214 children with 265 cervical spine injuries were included during the mentioned period. The mean age at the time of injury was 11.9 (± 3.9) years. In age group I, 24 (11.2%) patients were included, age group II consisted of 22 patients (10.3%), and 168 patients belonged to age group III (78.5%). Girls and boys were equally affected. In all age groups, falls and traffic accidents were the most common causes of cervical spine injuries. A total of 180 patients (84.1%) were treated conservatively, while 34 (15.9%) children underwent surgery. Distorsion/whiplash injury was the most common entity (n = 165; 68.2%). Children aged 0-9 years had significantly (p < 0.001) more frequent injuries of the upper cervical spine (C0-C2) compared to older age groups. Patients of age group III were more likely to suffer from injuries in subaxial localizations. Neurological deficits were rarely seen in all age groups. Head injuries did represent the most common accompanying injuries (39.8%, n = 92). CONCLUSIONS: The upper cervical spine was more frequently affected in young children. Older children more often suffered from subaxial pathologies. The majority of cervical spinal column injuries were treated conservatively. Nevertheless, 15% of the hospitalized children had to be treated surgically.

Conservative Binary Dynamics with a Spinning Black Hole at O(G

We compute the conservative two-body Hamiltonian of a compact binary system with a spinning black hole through O(G^{3}) to all orders in velocity, including linear and quadratic spin terms. To obtain our results we calculate the classical limit of the two-loop amplitude for the scattering of a massive scalar particle with a massive spin-1 particle minimally coupled to gravity. We employ modern scattering amplitude and loop integration techniques, in particular numerical unitarity, integration-by-parts identities, and the method of regions. The conservative potential in terms of rest-frame spin vectors is extracted by matching to a nonrelativistic effective field theory. We also apply the Kosower-Maybee-O'Connell (KMOC) formalism to calculate the impulse in the covariant spin formalism directly from the amplitude. We work systematically in conventional dimensional regularization and explicitly evaluate all divergent integrals that appear in full- and effective-theory amplitudes, as well as in the phase-space integrals that arise in the KMOC formalism.

Scattering Amplitudes, the Tail Effect, and Conservative Binary Dynamics at O(G

We complete the calculation of conservative two-body scattering dynamics at fourth post-Minkowskian order, i.e., O(G^{4}) and all orders in velocity, including radiative contributions corresponding to the tail effect in general relativity. As in previous calculations, we harness powerful tools from the modern scattering amplitudes program including generalized unitarity, the double copy, and advanced multiloop integration methods, in combination with effective field theory. The classical amplitude involves complete elliptic integrals, and polylogarithms with up to transcendental weight 2. Using the amplitude-action relation, we obtain the radial action directly from the amplitude, and match the known overlapping terms in the post-Newtonian expansion.

Iatrogenic Intracranial Hypotension after Surgery of Adolescent Idiopathic Scoliosis due to a Misplaced Screw within the Thoracic Thecal Sac.

We present the case of a postoperative intracranial hypotension due to a misplaced intrathecal screw. Although typical symptoms such as orthostatic headache were present immediately after surgery, diagnosis was hidden until 20 years later, resulting in a disastrous clinical course.

Morphological patterns of the rib cage and lung in the healthy and adolescent idiopathic scoliosis.

The morphology of the rib cage affects both the biomechanics of the upper body's musculoskeletal structure and the respiratory mechanics. This becomes particularly important when evaluating skeletal deformities, as in adolescent idiopathic scoliosis (AIS). The aim of this study was to identify morphological characteristics of the rib cage in relation to the lung in patients with non-deformed and scoliotic spines. Computed tomography data of 40 patients without any visible spinal abnormalities (healthy group) and 21 patients with AIS were obtained retrospectively. All bony structures as well as the right and left lung were reconstructed using image segmentation. Morphological parameters were calculated based on the distances between characteristic morphological landmarks. These parameters included the rib position, length, and area, the rib cage depth and width, and the rib inclination angle on either side, as well as the spinal height and length. Furthermore, we determined the left and right lung volumes, and the area of contact between the rib cage and lung. Differences between healthy and scoliotic spines were statistically analysed using the t-test for unpaired data. The rib cage of the AIS group was significantly deformed in the dorso-ventral and medio-lateral directions. The anatomical proximity of the lung to the ribs was nearly symmetrical in the healthy group. By contrast, within the AIS group, the lung covered a significantly greater area on the left side of the rib cage at large thoracic deformities. Within the levels T1-T6, no significant difference in the rib length, depth to width relationship, or area was observed between the healthy and AIS groups. Inferior to the lung (T7-T12), these parameters exhibited greater variability. The ratio between the width of the rib cage at T6 and the thoracic spinal height (T1-T12) was significantly increased within the thoracic AIS group (1.1 ± 0.08) compared with the healthy group (1.0 ± 0.05). No statistical differences were found between the lung volumes among all the groups. While the rib cage was frequently strongly deformed in the AIS group, the lung and its surrounding ribs appeared to be normally developed. The observed rib hump in AIS appeared to be formed particularly by a more ventral position of the ribs on the concave side. Furthermore, the rib cage width to spinal height ratio suggested that the spinal height of the thoracic AIS-spine is reduced. This indicates that the spine would gain its growth-related height after correcting the spinal deformity. These are the important aspects to consider in the aetiology research and orthopaedic treatment of AIS.

The effect of posterior compression of the facet joints for initial stability and sagittal profile in the treatment of thoracolumbar fractures: a biomechanical study.

PURPOSE: Surgical treatment of thoracolumbar A3-fractures usually comprises posterior fixation-in neutral position or distraction-potentially followed by subsequent anterior support. We hypothesized that additional posterior compression in circumferential stabilization may increase stability by locking the facets, and better restore the sagittal profile. METHODS: Burst fractures Type A3 were created in six fresh frozen cadaver spine segments (T12-L2). Testing was performed in a custom-made spinal loading simulator. Loads were applied as pure bending moments of ± 3.75 Nm in all six movement axes. We checked range of motion, neutral zone and Cobb's angle over the injured/treated segment within the following conditions: Intact, fractured, instrumented in neutral alignment, instrumented in distraction, with cage left in posterior distraction, with cage with posterior compression. RESULTS: We found that both types of instrumentation with cage stabilized the segment compared to the fractured state in all motion planes. For flexion/extension and lateral bending, flexibility was decreased even compared to the intact state, however, not in axial rotation, being the most critical movement axis. Additional posterior compression in the presence of a cage significantly decreased flexibility in axial rotation, thus achieving stability comparable to the intact state even in this movement axis. In addition, posterior compression with cage significantly increased lordosis compared to the distracted state. CONCLUSION: Among different surgical modifications tested, circumferential fixation with final posterior compression as the last step resulted in superior stability and improved sagittal alignment. Thus, posterior compression as the last step is recommended in these pathologies.

The reliability of the AOSpine Thoracolumbar Spine Injury Classification System in children: an international validation study.

PURPOSE: To evaluate the AOSpine Thoracolumbar Spine Injury Classification System and if it is reliable and reproducible when applied to the paediatric population globally. METHODS: A total of 12 paediatric orthopaedic surgeons were asked to review MRI and CT imaging of 25 paediatric patients with thoracolumbar spine traumatic injuries, in order to determine the classification of the lesions observed. The evaluators classified injuries into primary categories: A, B and C. Interobserver reliability was assessed for the initial reading by Fleiss's kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, sub-classification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff's alpha (αk) along with bootstrapped 95% CIs. A second round of classification was performed one-month later. Intraobserver reproducibility was assessed for the primary classifications using Fleiss's kappa and sub-classification reproducibility was assessed by Krippendorff's alpha (αk) along with 95% CIs. RESULTS: In total, 25 cases were read for a total of 300 initial and 300 repeated evaluations. Adjusted interobserver reliability was almost perfect (kF = 0.74; 95% CI 0.71 to 0.78) across all observers. Sub-classification reliability was substantial (αk= 0.67; 95% CI 0.51 to 0.81), Adjusted intraobserver reproducibility was almost perfect (kF = 0.91; 95% CI 0.83 to 0.99) for both primary classifications and for sub-classifications (αk = 0.88; 95% CI 0.83 to 0.93). CONCLUSION: The inter- and intraobserver reliability for the AOSpine Thoracolumbar Spine Injury Classification System was high amongst paediatric orthopaedic surgeons. The AOSpine Thoracolumbar Spine Injury Classification System is a promising option as a uniform fracture classification in children. LEVEL OF EVIDENCE: III.

The Feasibility of C1-C2 Screw-rod Fixation in the Children 5 Years of Age and Younger.

BACKGROUND: Atlantoaxial fixation is technically challenging in younger children. The C1-C2 screw-rod fixation technique is established for adults but limited data about the clinical and radiographical outcome for the treatment of children with 5 years of age or younger is available. METHODS: All files of children who were consecutively treated for spinal disorders were reviewed. Inclusion criteria for further evaluation were: 0 to 5 years of age at initial procedure; detailed surgical report of a posterior C1-C2 fusion with mass lateral and pedicle screw-rod fixation as described by Harms; a minimum clinical and radiographical follow-up of 24 months. The postoperative and last follow-up computed tomography scan and radiographs were used to assess the positioning and stability of the C1-C2 screw-rod construct. RESULTS: Eleven patients (3 boys) with a mean age of 46 months (range: 8 to 66 mo) fulfilled inclusion criteria and were evaluated retrospectively. The mean clinical and radiographical follow-up was 79 months (range: 24 mo to 170 mo). The diagnosis was atlantoaxial rotatory dislocation (4 cases), C1-C2 instability with subluxation (3 cases), atlantoaxial dislocation and os odontoideum (1 case), type II odontoid fracture (1 case), traumatic odontoid epiphysiolysis (1 case), and traumatic rupture of the transverse ligament with C1 subluxation (1 case). Intraoperatively and postoperatively no new neurovascular or vascular complication occurred. C1 lateral mass screws were placed correctly in all cases. Twenty-two C2 pedicle screws were placed correctly (85.7%), and 3 screws showed penetration of the pedicle wall (14.3%). No implant revision, implant failure, and pseudarthrosis were noted. Loss of correction was noted in 1 patient with unilateral C1-C2 fixation and a repeated dorsal fusion procedures were performed. A repeat procedure for implant removal and segmental release was performed in 3 patients to increase the axial rotation of the head. CONCLUSIONS: The C1-C2 screw-rod fixation is a safe technique that achieves solid fixation of the atlantoaxial complex in young children with various disorders. The technique preserves the joint and allows for segmental release via implant removal.

Gravitational Bremsstrahlung from Reverse Unitarity.

We compute the total radiated momentum carried by gravitational waves during the scattering of two spinless black holes at the lowest order in Newton's constant, O(G^{3}), and all orders in velocity. By analytic continuation into the bound state regime, we obtain the O(G^{3}) energy loss in elliptic orbits. This provides an essential step toward the complete understanding of the third-post-Minkowskian binary dynamics. We employ the formalism of Kosower, Maybee, and O'Connell (KMOC), which relates classical observables to quantum scattering amplitudes, and derive the relevant integrands using generalized unitarity. The subsequent phase-space integrations are performed via the reverse unitarity method familiar from collider physics, using differential equations to obtain the exact velocity dependence from near-static boundary conditions.

Interleukin-1ß and cathepsin D modulate formation of the terminal complement complex in cultured human disc tissue.

PURPOSE: Formation of terminal complement complex (TCC), a downstream complement system activation product inducing inflammatory processes and cell lysis, has been identified in degenerated discs. However, it remains unclear which molecular factors regulate complement activation during disc degeneration (DD). This study investigated a possible involvement of the pro-inflammatory cytokine interleukin-1ß (IL-1ß) and the lysosomal protease cathepsin D (CTSD). METHODS: Disc biopsies were collected from patients suffering from DD (n = 43) and adolescent idiopathic scoliosis (AIS, n = 13). Standardized tissue punches and isolated cells from nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) were stimulated with 5% human serum (HS) alone or in combination with IL-1ß, CTSD or zymosan. TCC formation and modulation by the complement regulatory proteins CD46, CD55 and CD59 were analysed. RESULTS: In DD tissue cultures, IL-1ß stimulation decreased the percentage of TCC + cells in AF and EP (P < 0.05), whereas CTSD stimulation significantly increased TCC deposition in NP (P < 0.01) and zymosan in EP (P < 0.05). Overall, the expression of CD46, CD55 and CD59 significantly increased in all isolated cells during culture (P < 0.05). Moreover, cellular TCC deposition was HS concentration dependent but unaffected by IL-1ß, CTSD or zymosan. CONCLUSION: These results suggest a functional relevance of IL-1ß and CTSD in modulating TCC formation in DD, with differences between tissue regions. Although strong TCC deposition may represent a degeneration-associated event, IL-1ß may inhibit it. In contrast, TCC formation was shown to be triggered by CTSD, indicating a multifunctional involvement in disc pathophysiology.

Scattering Amplitudes and Conservative Binary Dynamics at O(G

Using scattering amplitudes, we obtain the potential contributions to conservative binary dynamics in general relativity at fourth post-Minkowskian order O(G^{4}). As in previous lower-order calculations, we harness powerful tools from the modern scattering amplitudes program including generalized unitarity, the double copy, and advanced multiloop integration methods, in combination with effective field theory. The classical amplitude involves polylogarithms with up to transcendental weight two and elliptic integrals. We derive the radial action directly from the amplitude, and determine the corresponding Hamiltonian in isotropic gauge. Our results are in agreement with known overlapping terms up to sixth post-Newtonian order, and with the probe limit. We also determine the post-Minkowskian energy loss from radiation emission at O(G^{3}) via its relation to the tail effect.

Magnetically controlled growing rods in early onset scoliosis: radiological results, outcome, and complications in a series of 22 patients.

INTRODUCTION: Magnetically controlled growing rods (MCGR) for the surgical treatment of early onset scoliosis (EOS) allow non-invasive outpatient based distractions during spinal growth. The purpose of this study is to present the results of a single center case series of 22 patients, evaluate the effect of MCGR treatment on the development of spino-pelvic parameters during growth, and report initial outcomes after end of treatment. MATERIALS AND METHODS: Prospectively collected data of 22 EOS patients with MCGR treatment has been analyzed. The following radiological parameters were measured before index surgery, after index surgery, 1 year after index surgery, and at last follow-up: Cobb angle of the major curves, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Mean age at index surgery was 9.5 years (range: 4-14 years). Mean length of follow-up was 47.6 months (range: 25-121 months). Etiology of diagnosis was idiopathic in 14 patients, associated with neurofibromatosis in 2 patients, and neuromuscular or syndromic in 6 patients. RESULTS: Mean Cobb angle of the major curve was 57° preoperatively and 29° at last follow-up (p < 0.0005). Mean TK was 20.1° preoperatively and 20° at last follow-up (p > 0.05). Mean LL was 52.8° preoperatively and 53.2° at last follow-up (p > 0.05). Mean PI was 43.2° preoperatively and 46.3° at last follow-up (p > 0.05). Mean PT was 4.1° preoperatively and 5.8° at last follow-up (p > 0.05). Mean SS was 39.2° preoperatively and 41.7° at last follow-up (p > 0.05). 14 patients finished treatment: nine received final fusion and five received rod removal without fusion. Twelve complications occurred: one deep wound infection, six patients developed proximal junctional kyphosis (PJK), one rod fracture, two rods failed to distract, one deformity progressed after rod removal and required spinal fusion, and one patient developed autofusion of the spine prior to end of treatment. CONCLUSION: MCGR treatment is able to control deformity progression. Complication rate was 54.5%. Sagittal balance was not altered and treatment does not seem to have a negative impact on the development of spino-pelvic parameters during growth. Optimal end of treatment for the individual patient still has to be defined.