Anterior Proximal Tibial Screw Hemiepiphysiodesis Decreases Posterior Tibial Slope in Knee Flexion Contracture: A Case Report.

CASE: A 13-year-old adolescent boy with hemiplegic cerebral palsy suffering from fixed knee flexion deformity of 10° despite extensive conservative treatment. Owing to a posterior tibial slope (PTS) of 16°, anterior hemiepiphysiodesis was applied to the proximal tibia. The 2 screws were removed after 9 months. Final follow-up at 16 months showed complete knee extension and a PTS of 4°. CONCLUSION: The presented technique is a good alternative in knee flexion deformity with an increased PTS and has surprisingly not been described in the literature. This might be worth considering for other pathologies such as pediatric anterior cruciate ligament injury with an increased PTS.

Fractures of the Bilateral C2 Neurocentral and Lateral Dental Synchondroses with Kyphotic C1-C2 Subluxation in a 3-Year-Old Girl: A Description of a Rare Fracture Pattern and Its Treatment: A Case Report.

CASE: Spinal fractures are rare in young children. Because spinal anatomy and biomechanics differ in children and adults, knowledge of the deviations of the juvenile spine is necessary for adequate treatment. We present the case of a young girl with an unusual C2 fracture that included rupture of both of the neurocentral and lateral dental synchondroses, with an opening of the synchondroses and a caudal dislocation of both vertebral arches following a head-on motor vehicle collision. The whole body and apex of the dens was displaced anteriorly and cranially with a kyphotic angulation of 34°. We describe the treatment and clinical and radiographic outcome after 1 year. CONCLUSION: Using passive hyperextension and distraction of the head, a closed open-mouth digital reduction was performed under continuous fluoroscopy. At the 1-year follow-up, the patient had full range of motion of the head without pain or neurologic dysfunction.

A balanced approach for stable hips in children with cerebral palsy: a combination of moderate VDRO and pelvic osteotomy.

BACKGROUND: Hip reconstructive surgery in cerebral palsy (CP) patients necessitates either femoral varus derotational osteotomy (VDRO) or pelvic osteotomy, or both. The purpose of this study is to review the results of a moderate varisation [planned neck shaft angle (NSA) of 130°] in combination with pelvic osteotomy for a consecutive series of patients. METHODS: Patients with CP who had been treated at our institution for hip dysplasia, subluxation or dislocation with VDRO in combination with pelvic osteotomy between 2005 and 2010 were reviewed. RESULTS: Forty patients with a mean follow-up of 5.4 years were included. The mean age at the time of operation was 8.9 years. The majority were non-ambulant children [GMFCS I-III: n = 11 (27.5 %); GMFCS IV-V: n = 29 (72.5 %)]. In total, 57 hips were treated with both femoral and pelvic osteotomy. The mean pre-operative NSA angle of 152.3° was reduced to 132.6° post-operatively. Additional adductor tenotomy was performed in nine hips (16 %) at initial operation. Reimers' migration percentage (MP) was improved from 63.6 % pre-operatively to 2.7 % post-operatively and showed a mean of 9.7 % at the final review. The results were good in 96.5 % (n = 55) with centred, stable hips (MP <33 %), fair in one with a subluxated hip (MP 42 %) and poor in one requiring revision pelvic osteotomy for ventral instability. CONCLUSIONS: This approach maintains good hip abduction and reduces soft-tissue surgery. Moderate varisation in VDRO in combination with pelvic osteotomy leads to good mid-term results with stable, pain-free hips, even in patients with severe spastic quadriplegia.

Personalized Cancer Care: Risk Prediction, Early Diagnosis, Progression, and Therapy.

At the annual prestigious International Symposium of the Fritz-Bender Foundation, Munich, 18-20 May, 2016, researchers, clinicians, and students discussed the state of the art and future perspectives of genomic medicine in cancer. Genomic medicine (also known as precision medicine/oncology) should help clinicians to provide a more precise diagnosis and therapy in oncology for individual patients. The meeting focused on next-generation sequencing methods, analytical computational analysis of big data, and data mining on the way to translational and evidence-based medicine. The meeting covered the social and ethical impact of genomic medicine as well as news and views on antibody targeting of intracellular proteins, on the architecture of intracellular proteins and their impact on carcinogenesis, and on the adaptation of tumor therapy in due consideration of tumor evolution. Subheadings like "Genetic Profiling of Patients and Risk Prediction," "Molecular Profiling of Tumors and Metastases," "Tumor-Host Microenvironment Interaction and Metabolism," and "Targeted Therapy" were subsumed under the main heading of "Personalized Cancer Care."

Normal values of bony, cartilaginous, and labral coverage of the infant hip in MR imaging.

BACKGROUND: Magnetic resonance imaging (MRI) is becoming more popular in the evaluation of residual hip dysplasia. Normal values of the bony, cartilaginous, and labral coverage in MRI are not published. The aim of our study was to establish reference values for normal hips at different ages and to assess the interobserver variability of such measurements. METHODS: MRIs of 115 normal hips in 73 children were analyzed. The bony, cartilaginous, and labral acetabular index (AI bone/cartilage/labrum) was measured in the coronal plane just posterior to the inferior branch of the triradiate cartilage. To determine interobserver variability, measurements were made by 3 different observers. Percentile graphs were established from the Student t distribution of the measurements grouped by 2 years of age. RESULTS: Global interobserver variability for the measurement of the AI bone was excellent [intraclass correlation coefficient (ICC)=0.88]. For the AI cartilage and labrum the ICC was somewhat lower (ICC 0.78) but still rated as good. Age-dependent percentile graphs of the AI bone, cartilage, and labrum are presented. Although the AI bone decreased during childhood, the AI cartilage as well as the AI labrum stays relatively constant with the 50 percentile around 5 degrees for the AI cartilage and -5 degrees for the AI labrum. The 90 percentile is around 10 degrees for the AI cartilage and 0 degrees for the AI labrum. CONCLUSIONS: We present percentile graphs of age-related normal values. Although bony coverage increases during childhood, cartilaginous and labral coverage stay constant. We think that measuring an AI cartilage above 10 degrees or an AI cartilage above 0 degrees might be a good additional parameter to classify hips into the group of residual dysplasia. CLINICAL RELEVANCE: The knowledge of normal values for cartilaginous and labral coverage is a valuable adjunct in decision-making for secondary surgery in residual dysplasia. This was a retrospective cross-sectional study.

LCP 140° Pediatric Hip Plate for fixation of proximal femoral valgisation osteotomy.

PURPOSE: Femoral osteotomy is one of the most widely performed reconstructive operations in pediatric orthopedic surgery. Many implants for fixation have been used, but so far there is no literature about the application and outcome of the LCP 140° Pediatric Hip Plate for proximal femoral valgisation in children. METHODS: Data of patients with a valgisation of the proximal femur using the LCP 140° Pediatric Hip Plate between February 2011 and July 2012 were retrospectively collected and analyzed. RESULTS: We included 10 patients (11 hips) with a mean follow-up of 15.3 ± 6.3 months (range 5.6-23 months). The mean age was 9.6 ± 1.2 years (range 7.3-11.8 years) with a mean hospital stay of 5.2 ± 1.7 days (range 3-9 days). Callus formation was observed in all cases at 6 weeks postoperative control and consolidation was shown after a mean time of 14.1 ± 2.3 weeks (range 12.1-19.1 weeks). There was no delayed union or any case of non-union in our series. The stability of the operative reduction including the corrected neck-shaft angle (mean 19° ± 7.9°; range 10.5°-38.5°) was maintained during the follow-up period. No cases of recurrence (varisation) or complications requiring further treatment or revision were observed. CONCLUSIONS: In our series, the 140° LCP Pediatric Hip Plate was shown to be safe and applicable in the clinical setting with good results. We therefore consider this device to be valuable for the correction of pathologic varus conditions of the proximal femur in children.

Persisting growth after prophylactic single-screw epiphysiodesis in upper femoral epiphysis.

BACKGROUND: Prophylactic fixation of the contralateral hip in cases of slipped upper femoral epiphysis is controversial. Therefore, using a single-cannulated screw has been widely accepted. However, differing reports exist on the occurrence of persisting growth after prophylactic epiphysiodesis. The aim of this retrospective study was to evaluate the presence of persisting growth of the upper femoral epiphysis after prophylactic fixation. METHODS: From 2006 until 2009, 11 children underwent prophylactic pinning using a single-cannulated 6.5-mm cancellous screw. Time to fusion, persisting growth, and overgrowing of the screw were measured on plain radiographs taken postoperatively and at least after the growth plate was fused. RESULTS: All patients except 1 (91%) showed a persisting growth of the epiphysis, and in 2 cases a hardware replacement was necessary. The mean increase of the femoral neck length was 8.2% (SEM 1.46%). Mean follow-up was 37 months (range, 12 to 49 mo). All patients had a Risser sign grade 0 at the time of surgery, and equal or less than grade 3, when the growth plate was fused. CONCLUSIONS: Despite previous reports that a prophylactic fixation using a single-cannulated cancellous screw is unproblematic and safe, we showed that in our series growth persistence was the rule and in some cases the physeal overgrowth necessitates a hardware replacement. Careful follow-up until fusion of the growth plate should be recommended.

Flexible intramedullary nailing in children: nail to medullary canal diameters optimal ratio.

BACKGROUND: Postoperative axial deviations and delayed unions are possible complications after flexible intramedullary nailing (FIN). The goals of this study were to determine if a correlation exists between occurrence of the above complications and the ratio of the diameter between nail and medullary canal [nail diameter (ND)/MCD ratio], to study the interobserver variability in the measurement of MCD, and to define a threshold to be respected to optimize the results. METHODS: Eighty-one consecutive diaphyseal fractures treated by means of FIN were evaluated. The ND/MCD ratios were determined by 2 independent observers. Axial deviations were defined as 5-degree angulation or more observed before bone union. Absence of bone union at 3 months was considered as delayed union. Statistical analysis was made for interobserver variability of MCD, dependency between occurrence of complications and ND/MCD ratio and eventual confounding variables (age, weight, sex, and fracture location). RESULTS: Of the 81 fractures, 14 presented with an axial deviation and 3 with a delayed union. Interobserver variability of MCD diameter was excellent (intraclass correlation: 0.96). Occurrence of the above complications was significantly associated with a low ND/MCD ratio (P=0.0002) but with none of the examined confounding variables. Receiver operating characteristic analysis showed absence of complications with a ND/MCD ratio >35% with a sensitivity of 100% and specificity of 89%. Related with the MCD measurements variability, a safe threshold of 40% can be suggested. CONCLUSIONS: In FIN, ND>40% to the MCD should be chosen to avoid complications, besides respecting the technical principles. Measuring the medullary canal diameter in order to choose correct nail size is reproducible between different observers. In adolescents with a medullary canal diameter of >10 mm in femur or tibia fractures, alternative methods of osteosynthesis than FIN should be considered. SIGNIFICANCE: This work statistically confirms that a ND/MCD ratio of >40% must be respected to avoid some complications in FIN. LEVEL OF EVIDENCE: Level III.

Personalized cancer care conference.

The Oslo University Hospital (Norway), the K.G. Jebsen Centre for Breast Cancer Research (Norway), The Radiumhospital Foundation (Norway) and the Fritz-Bender-Foundation (Germany) designed under the conference chairmen (E. Mihich, K.S. Zänker, A.L. Borresen-Dale) and advisory committee (A. Borg, Z. Szallasi, O. Kallioniemi, H.P. Huber) a program at the cutting edge of "PERSONALIZED CANCER CARE: Risk prediction, early diagnosis, progression and therapy resistance." The conference was held in Oslo from September 7 to 9, 2012 and the science-based presentations concerned six scientific areas: (1) Genetic profiling of patients, prediction of risk, late side effects; (2) Molecular profiling of tumors and metastases; (3) Tumor-host microenvironment interaction and metabolism; (4) Targeted therapy; (5) Translation and (6) Informed consent, ethical challenges and communication. Two satellite workshops on (i) Ion Ampliseq-a novel tool for large scale mutation detection; and (ii) Multiplex RNA ISH and tissue homogenate assays for cancer biomarker validation were additionally organized. The report concludes that individual risk prediction in carcinogenesis and/or metastatogenesis based on polygenic profiling may be useful for intervention strategies for health care and therapy planning in the future. To detect distinct and overlapping DNA sequence alterations in tumor samples and adjacent normal tissues, including point mutations, small insertions or deletions, copy number changes and chromosomal rearrangements will eventually make it possible to design personalized management plans for individualized patients. However, large individualized datasets need a new approach in bio-information technology to reduce this enormous data dimensionally to simply working hypotheses about health and disease for each individual.

Spontaneous reduction of spondylolisthesis during growth: a case report.

Isthmic spondylolisthesis is a common cause of low back pain in children. It is associated with a defect in the pars interarticularis of the vertebra. The treatment depends on the clinical course and degree of spondylolisthesis. Low-grade isthmic spondylolisthesis usually shows a benign course without significant progression and therefore, conservative treatment is advised. Although isthmic pars defect can heal, initial existing degree of slippage persists. A complete reversion of deformity was never described yet. We present the case of a 7½-year-old girl with symptomatic grade 2 isthmic spondylolisthesis according to the Meyerding classification. Without any specific therapy, there was a radiologically documented near total reversion of slippage and total relief of clinical symptoms during 8 years of follow-up. Computed tomography scan after this period showed persisting pars interarticularis defect without signs of healing. This case report indicates that during growth, spontaneous reversion of vertebral slip in isthmic spondylolisthesis can occur, even without healing of the pars defect.

Flexible intramedullary nailing for distal femoral fractures in patients with myopathies.

PURPOSE: Distal femoral fractures are quite common in nonambulating patients with myopathies, as they present marked osteoporosis. The deterioration of preexisting knee flexion contracture is a known problem, as these fractures are usually angulated posteriorly. The goals of treatment are to reduce immobilization and bed rest to a minimum, prevent function loss, and prevent refracture. The aim of our work was to investigate if these goals can be achieved by an operative treatment with closed reduction and flexible intramedullary nailing (FIN). METHODS: Six distal femoral fractures in four nonambulating patients with myopathies (three Duchenne muscular dystrophy and one nemaline myopathy) were treated with FIN between 2005 and 2011. Patient charts and radiographs were reviewed to determine if intra- or postoperative complications occurred and to detect the interval to wheelchair mobilization and hospital discharge. Pre- and postoperative knee flexion contracture was noted from the patient charts of our reeducation unit, where patients were already known preoperatively. RESULTS: Wheelchair mobilization without further immobilization after an interval of 2-3 days was possible. No aggravation of knee flexion contracture was detected in our patient series. No complications associated to the operative treatment itself and no refractures in the follow up occurred. CONCLUSION: Our experience showed that FIN is a low invasive and sufficiently stable osteosynthesis in such fractures. Left in place, nails will reinforce mechanical stability.

High-frequency electromagnetic dynamics properties of THP1 cells using scanning microwave microscopy.

Microwave measurements combined with scanning probe microscopy is a novel tool to explore high-localized mechanical and electrical properties of biological species. Complex permittivities and permeabilities are detected through slight variations of an incident microwave signal. Here we report the high-frequency dependence of the electromagnetic dynamic characteristics in human monocytic leukemia cells (THP1) through local measurements by scanning microwave microscopy (SMM). The amplitude and phase images were shown to depend on the applied resonance frequency. While the amplitude yields information about the resistivity determined by the water and the ionic strength, the phase information reflects the dielectric losses arising from the fluid density.

Open mouth digital reduction of an odontoid synchondrosis fracture: a case report.

The "odontoid synchondrosis fracture" represents a rare but typical injury of the upper cervical spine in children less than 7 years. Conservative treatment with closed reduction and external fixation shows fusion rates across the synchondrosis in about 90% cases. When closed reduction cannot be achieved, open reduction and internal fixation is usually performed. We present the case of a girl aged 3 years and 5 months, whose closed reduction by passive manipulation of the head failed, but the same could successfully be achieved through transoral manipulation of the dens. After treatment with a Minerva plaster cast, the fracture was healed without complication. We suggest transoral manipulation in cases of otherwise irreducible "odontoid synchondrosis fracture." This technical hint may avoid unnecessary surgery in children with this type of injury.

Fixation of subtrochanteric extending/derotational femoral osteotomies with the Locking Compression Plate in ambulatory neuro-orthopaedic patients.

PURPOSE: Patients with neuro-orthopaedic disorders often develop hip flexion contractures or rotational hip deformities. Increasing deformities impair the already diminished walking abilities and proximal femoral osteotomies are often performed to maintain/improve walking abilities. Fixation of the osteotomies with condylar plates has been successfully used but does often not allow immediate postoperative full weight bearing. To avoid a substantial postoperative rehabilitation deficit and additional bone loss due to inactivity, a postoperative treatment with full weight bearing is, therefore, wishful. Newer fixed-angled implants with stronger anchoring in osteopenic bone might fit these demands. The objective of this study was to evaluate bone healing and the complication rate after proximal extending and/or derotational femoral osteotomy fixed with 3.5/4.5 Locking Compression Plate (LCP; Synthes(®)) and postoperative full weight bearing in ambulatory neuro-orthopaedic patients. METHODS: Fifteen ambulatory neuro-orthopaedic patients (12 cerebral palsy [CP], 1 trisomy 21, 2 hemiparesis) with a mean age of 13.7 years (range 7-22) with hip flexion contractures and/or rotational deformities underwent subtrochanteric (n = 26) osteotomy between July 2004 and October 2007. All patients were allowed to bear their full weight postoperatively. We investigated the fusion rate, implant failure, and general complication rate until union had occurred. RESULTS: Fourteen patients (mean weight 42.0 kg [range 21.8-59]) uneventfully achieved solid fusion. One patient (19 years of age, 73 kg) needed revision surgery due to implant failure with consecutive varus deformity and achieved solid fusion after the second intervention. Besides one superficial wound infection, no other complications occurred. CONCLUSIONS: Subtrochanteric extending and/or derotational osteotomies fixed with an LCP are a reliable procedure in neuro-orthopaedic patients. Most patients can be treated with early postoperative full weight bearing. However, in heavier patients, possible implant failure must be considered.

Treatment of reduced femoral antetorsion by subtrochanteric rotational osteotomy.

The purpose of this study was to assess bone healing and complication rate following subtrochanteric rotational osteotomy fixed with a 4.5/5.0 Locking Compression Plate (LCP, Synthes) for reduced femoral antetorsion with early full weight bearing. The effects of the osteotomy on the range of internal rotation of the hip and complaints due to reduced antetorsion were also recorded. Between July 2004 and October 2007, 25 children (39 hips) with a mean age of 13 years (range, 9-18 years) were treated for reduced internal rotation of the hip by a subtrochanteric rotational osteotomy. Four patients (six hips) were excluded from this study due to concomitant surgeries prohibiting full weight bearing. Of the 21 patients who were allowed full weight bearing, nine had a unilateral and twelve a single-stage bilateral correction. We investigated time to union, implant failure, and complication rate as well as improvement in the range of internal rotation. All osteotomies healed without secondary displacement or angulation. Internal rotation improved from a mean of 8.6 degrees (-5 degrees to 20 degrees) preoperatively to 37.3 degrees (25 degrees to 60 degrees) postoperatively. We noted no complication related with the femoral osteotomy. Subtrochanteric rotational osteotomy appeared as a reliable procedure to improve internal rotation of the hip. Fixation with 4.5/5.0 LCP allows simultaneous bilateral correction and immediate full weightbearing with crutches, with a minimal risk of implant failure.

Non-Hamiltonian molecular dynamics implementation of the Gibbs ensemble method. I. Algorithm.

In this paper (paper I) and the following paper (paper II) [C. Bratschi, H. Huber, and D. J. Searles, J. Chem. Phys. 126, 164105 (2007)], a new molecular dynamics algorithm implementing the Gibbs ensemble will be presented and then on applied to the liquid-vapor coexistence curve for two ab initio CO2 potentials. In paper I, the Gibbs ensemble molecular dynamics algorithm using non-Hamiltonian molecular dynamics techniques is introduced. It is shown that states of the correct probability density function are sampled and the correct exchange probability is generated. The extended system Nose-Hoover formalism is used to generate a constant temperature ensemble with equal pressures in the subsystems, combined with single particle transfers between the subsystems, over several time steps, to get equal chemical potentials.

Non-Hamiltonian molecular dynamics implementation of the Gibbs ensemble method. II. Molecular liquid-vapor results for carbon dioxide.

The Gibbs ensemble molecular dynamics algorithm introduced in the preceding paper (paper I) [C. Bratschi and H. Huber, J. Chem. Phys. v126, 164104 (2007)] is applied to two recently published CO2 ab initio pair potentials, the Bock-Bich-Vogel and symmetry-adapted perturbation theory site-site potentials. The critical properties of these potentials are calculated for the first time. Critical values and points in the single and two-phase zones are compared with Monte Carlo results to demonstrate the accuracy of the molecular dynamics algorithm, and are compared with experiment to test the accuracy of the potentials. Pressure calculations in the liquid, gas, and supercritical states are carried out and are used to explain potential-related effects and systematic discrepancies. The best ab initio potential yields results in good agreement with experiment.

Beyond the resonant dipole interaction model: resolution of a discrepancy between experimental and calculated structures of the carbon dioxide cyclic planar trimer.

A dimer and two trimers of carbon dioxide are known experimentally and have also been studied computationally. Whereas the calculated and experimental structures are in excellent agreement for the dimer and in fair agreement for the nonplanar trimer of C2 symmetry, the cyclic planar trimer shows a significant discrepancy in the angle beta which measures the deviation from D(3h) symmetry. All calculations yield for this angle values around 40 degrees in contrast to the experimental angle of (33.8+/-0.5) degrees . The latter was obtained from the experimental shift of the asymmetric vibrational stretch line of the trimer relative to the monomer using the resonant dipole-dipole interaction model. This model corresponds to the leading term in the molecular transition multipole expansion (TMPE) of the electrostatic coupling contribution to vibrational shifts. In this paper we go beyond the resonant dipole-dipole interaction model and include higher-order moments. To this end we use the first-order perturbation approach in combination with the (CO2)2 ab initio symmetry-adapted perturbation theory (SAPT)-s potential to calculate the vibrational shifts and scale the CO2 SAPT-s point charges to reproduce the experimental transition dipole moment of the gas-phase CO2 asymmetric stretch. The transition dipole-dipole term in the TMPE of the electrostatic coupling plays a predominant role in the vibrational shifts of the CO2 dimer and nonplanar trimer, however, to explain the vibrational shifts of the cyclic planar trimer the inclusion of the higher-order vibrationally induced moments is needed. As the angle beta in this trimer approaches the value of 40 degrees the dipole-dipole term in the electrostatic coupling disappears and the sum of the higher-order terms becomes important for the correct description of the vibrational shifts. Hence applying the resonant dipole-dipole interaction model to the experimentally observed vibrational shift for the cyclic planar trimer gives the wrong angle beta for this trimer. The higher-order terms in the TMPE of the electrostatic coupling which are not negligible for the vibrational shifts of the cyclic planar trimer include vibrationally induced dipole-octupole and quadrupole-quadrupole interactions.

Calculation of the deuteron quadrupole relaxation rate in a mixture of water and dimethyl sulfoxide.

An approach is presented that allows NMR relaxation rates to be determined for a complex mixture, and it is applied to a dimethyl sulfoxide/water solution. This approach is novel for such systems, having only been used for simple systems such as atomic liquids or atomic ions in liquids until now. It involves use of a predetermined, quantum mechanical, multidimensional property surface in a simulation. The results are used in conjunction with the simulated rotational correlation time to calculate the deuteron quadrupole coupling constant (DQCC), in an analogous approach to the one used by experimentalists, and to examine the surprising experimental findings for the composition dependence of the DQCC in the dimethyl sulfoxide/water mixture. Experiments have suggested that the DQCC for a mixture of 5% dimethyl sulfoxide in water is close to the DQCC of ice, whereas its value increases to a value close to the gas value with further dilution.(1) The results are further critically analyzed using combinations of different experimental and theoretical results from the literature.