Disc volume properties from MRI in adolescent idiopathic scoliosis: correlation to surgical outcome

In young scoliotic patients, the post-operative consequence of spine fusion upon the free lower lumbar spine is one of the major concerns of the surgical treatment. The remodeling of free-motion segment and the role of discs below thoraco-lumbar fusions remains unknown. However, disc hydration and mass exchange flow between disc and vertebral body should play a significant role in the mechano-biology of the vertebral segment. Magnetic resonance imaging is relevant to study intervertebral discs in young scoliotic patients since related to hydration and non-radiant

Pelvic reorientation osteotomies and acetabuloplasties in children. Surgical technique

SummaryThe objectives of pelvic osteotomies are to improve femoral head coverage and coxofemoral joint stability. The most currently used osteotomies can be divided into reorientation osteotomies (Salter and Pol le Cœur triple osteotomy) and acetabuloplasties (Pemberton and Dega). All these osteotomies share an identical installation on the table and bikini-type incision. The Salter osteotomy uses a single osteotomy line located at the inferior gluteal line. The Pol Le Cœur triple pelvic osteotomy combines innominate osteotomies of the iliopubic and ischiopubic rami via a genitofemoral approach (inguinal). In these two reorientation osteotomies, the acetabulum tilts in retroversion, improving the anterior and lateral coverage but reducing the posterior coverage. In the Pemberton acetabuloplasty, the osteotomy line is incomplete. It begins anteriorly between the iliac spines and ends posteriorly immediately above the triradiate cartilage. The posterior part of the ilium remains intact. The Pemberton acetabuloplasty causes retroversion and plicature of the acetabulum responsible for reducing its diameter. Anterior and lateral coverage of the femoral head is improved and posterior coverage remains unchanged. In the Dega acetabuloplasty, the osteotomy line is incomplete. It begins laterally above the acetabulum and terminates just above the triradiate cartilage. The medial part of the ilium remains intact. The Dega acetabuloplasty reduces the diameter of the acetabulum and improves overall femoral head coverage (anterior, lateral, and posterior)

Studies on the stability of the cyclobutane b-aminoacid skeleton : a cautionary tale

The 2-amino-1-cyclobutanecarboxylic acid skeleton undergoes facile retro-Mannich type ring opening in solution, which may lead to unexpected by-products during its synthesis or manipulatio

Influence of fluid-flow direction on effective permeability of the vertebral end plate: an analytical model

Convective transports in the vertebral end plate (VEP) play a significant role in the homeostasis of the spine. A few studies hypothesised that the hydraulic resistance or effective permeability of the VEP could be dependant upon fluid-flow direction. Results were influenced by species, region of interest within the end plate and pathology. Some results were contradictory. We propose an analytical model based on steady-state Newtonian flows in capillary media to develop a phenomenological analysis of convective transport through the VEP. This dependence was established using a biquadratic analytical function involving porosities of subchondral bone, capillary bed and cartilage end plate. Discussion of results provided a theoretical justification for variable and/or contradictory experimental results concerning the amount of energy lost by fluid during its course through the end plate. Tissue porosities and, especially, those relative to the capillary bed could strongly influence the dependence of fluid energy loss on flow direction and could potentially modify tissue homeostasis related to the day and night cycle

Arthroscopic treatment of intercondylar eminence fractures with intraepiphyseal screws in children and adolescents

INTRODUCTION: Tibial intercondylar eminence fracture rarely occurs in childhood. Its treatment requires anatomic reduction to provide knee stability and a rigid fixation to minimize postoperative immobilization time. HYPOTHESIS: Arthroscopy combined with fluoroscopy with intra-epiphyseal ASNIS screw fixation can meet the requirements of this treatment. MATERIAL AND METHODS: The series comprised 24 patients (mean age: 11 years) with Meyers and McKeever type II tibial intercondylar eminence fractures (n=15) or type III (n=9), operated on between 2011 and 2013. Fixation with 4-mm ASNIS screws was placed arthroscopically. The demographic data, associated lesions, radiological union, stability, functional result, and the Lysholm score were evaluated. RESULTS: With a mean follow-up of 2 years, the mean Lysholm score was 99.3 for type II and 98.6 for type III fractures. At the 6th postoperative week, range of motion in the operated knees was identical to the healthy knees. At the 12th postoperative week, there was no sign of anterior laxity. Twelve cases included meniscal entrapment, but no significant difference was observed in the functional results. DISCUSSION, CONCLUSION: ASNIS screw fixation under arthroscopy can be successfully applied in the treatment of types II and III tibial intercondylar eminence fractures in children. This technique provides excellent stability, allows early weigh-tbearing, and preserves function of the knee and its growth. LEVEL OF EVIDENCE: IV, retrospective study

Bone lengthening using fitbone(r) motorized intramedullary nail: the first experience in France.

INTRODUCTION: Intramedullary limb lengthening systems include mechanical systems (the Albizzia nail and the ISKD nail) as well as motorized systems with the Fitbone(®) (Wittenstein, Igersheim, Germany) and the Precice(®) (Ellipse Technologies, Irvine, CA, USA) nails. We hypothesized that limb lengthening using the Fitbone(®) nail was reliable, reproducible, and comfortable for the patient. PATIENTS AND METHODS: Between 2010 and 2013, a prospective single-center, single-operator (FA) study was conducted on patients who had undergone limb lengthening using the Fitbone(®) nail. The inclusion criteria were length discrepancy of the limbs equal to or greater than 25 mm or a short stature. The exclusion criteria were indications for cosmetic reasons and/or growth plates that were still open. The lengthening parameters were assessed postoperatively and at the last follow-up. Lengthening was considered achieved when the lengthening objective did not differ by more than 5 mm. All complications were noted. A statistical analysis was performed. RESULTS: Twenty-six Fitbone(®) nails were implanted in 23 patients, in the femur in 15 cases and the tibia in 11 cases. The patients' mean age was 22.5 years (range: 15-53 years) and the mean follow-up was 3.4 years (range: 2-5.3 years). The limb lengthening targeted was obtained in 23 cases (88%) and the mean lengthening was 45.3±18 mm (range: 20-80 mm). The mean time to healing was 277±167 days (range: 86-638 days). The mean healing index was 73±57 days/cm for the femurs and 83.5±65 days/cm for the tibias. The mean complication rate was 15.4%. DISCUSSION: This study emphasizes the good short-term results of this motorized intramedullary lengthening system. An evaluation over the longer term and with a higher number of patients remains necessary. LEVEL OF EVIDENCE: IV: uncontrolled, prospective, continuous study

Synthesis of novel β-aminocyclobutanecarboxylic acid derivatives by a solvent-free aza-Michael addition and subsequent ring closure

Novel beta-aminocyclobutanecarboxylic acid derivatives were prepared via a sequential solvent-free aza-Michael addition of benzophenone imine across 3-halopropylidenemalonates and base-induced ring closure. These highly substituted cyclobutanedicarboxylic acid derivatives were subjected to a reactivity study which demonstrated the tendency of these donor-acceptor substituted four-membered rings to be converted into their corresponding ring-opened products

Treat Iron-Related Childhood-Onset Neurodegeneration (TIRCON)—An International Network on Care and Research for Patients With Neurodegeneration With Brain Iron Accumulation (NBIA)

In order to improve clinical care, coordinate research activities and raise awareness for the ultra-orphan Neurodegeneration with Brain Iron Accumulation (NBIA) disorders, a group of NBIA clinicians and researchers, industry partners and patient advocacies from six European countries, Canada and the US joined forces in 2010 to set-up the collaborative initiative TIRCON (Treat Iron-Related Childhood-Onset Neurodegeneration). As a research project, TIRCON received funding in the 7th Framework Programme (FP7) of the European Union (EU) from 2011 to 2015. After successful and timely completion of the initial FP7 project, funding and donations from industry and patient organizations have sustained the further development of TIRCON's dedicated clinical research infrastructure and its governance architecture, as well as the ongoing efforts undertaken in the NBIA community to establish a network of care. From the beginning, the University Hospital of the Ludwig-Maximilians-University in Munich, Germany has been coordinating the TIRCON initiative. It consists of 8 work packages, of which the first double-blind, placebo-controlled, randomized, multi-site clinical trial in NBIA (deferiprone in PKAN, completed) and a global patient registry and biobank, currently comprising baseline and follow-up data of > 400 NBIA patients have gained particular importance. Here we describe TIRCON's history with all the challenges and achievements in diagnosing and treating NBIA. Today, TIRCON lays the ground for future clinical care and research. In these times, it may also serve as a good example of well-directed governmental funding and fruitful international scientific collaboration

Sagittal spino-pelvic organization influences the biomechanical behavior of the intervertebral disc after idiopathic scoliosis surgery: a prospective study with minimum 2 years follow up

Purpose: To analyse the biomechanical properties of the intervertebral disc after scoliosis surgery according to the underlying spino-pelvic organization