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BackgroundGuided growth by tension band plating is commonly used to correct coronal plane deformity. The purpose of this study was to measure the effect and further define parameters that influence results in coronal plane deformity around the knee.MethodsThe retrospective multicentre study included data on 967 physes in 537 patients, with an average follow-up of 16 months after plate insertion. Alignment analysis was compared preoperatively and in at least two measurements postoperatively, as well as with parameters that influence the rate and amount of correction.ResultsAverage age at plate implantation was 11.35 years (SD 3.29).Of those with femoral deformities, 85% of the patients finished the treatment and of those, 70% were corrected to standard alignment, while 14% have not yet achieved correction, and are still growing.Of those with tibial deformities, 75% of the patients finished the treatment and of those 80% were corrected to standard alignment, while 25% have not yet achieved correction and are still growing.The calculated rate of correction was 0.77°/month for the femur and 0.79°/month for the tibia.In terms of complications, the overall rate of infection was 1.48%. In three patients (0.55%) screw breakage was recorded.Factors found to significantly influence the amount of correction were age at plate implantation and direction of deformity.ConclusionTemporary hemiepiphysiodesis takes the advantage of physiological physeal growth to effectively treat angular deformities. Success of treatment is influenced by the age of the patient at plate implantation and direction of deformity.Level of EvidenceIV

Background The between-observer reliability of repeated anatomic assessments in pediatric orthopedics relies on the precise definition of bony landmarks for measuring angles, indexes, and lengths of joints, limbs, and spine. We have analyzed intra-and interobserver reliability with a new digital measurement system (TraumaCad Wizard TM ). Methods Five pediatric orthopedic surgeons measured 50 digital radiographs on three separate days using the TraumaCad system. There were 10 anterior-posterior (AP) pelvic views from developmental dysplasia of the hip (DDH) patients, 10 AP pelvic views from cerebral palsy (CP) patients, 10 AP standing view of the lower limb radiographs from leg length discrepancy (LLD) patients, and 10 AP and 10 lateral spine X-rays from scoliosis patients. All standing view of the lower limb radiographs were calibrated by the software to allow for accurate length measurements, using as reference a 1-inch metal ball placed at the level of the bone. Each observer performed 540 measurements (totaling 2,700). We estimated intra-and interobserver standard deviations for measurements in all categories by specialists and nonspecialists. The intraclass correlation coefficient (ICC) summarized the overall accuracy and precision of the measurement process relative to subject variation. We examined whether the relative accuracy of a measurement is adversely affected by the number of bony landmarks required for making the measurement. Results The overall ICC was [0.74 for 13 out of 18 measurements. Accuracy of the acetabular index for DDH was greater than for CP and relatively low for the centeredge angle in CP. Accuracy for bone length was better than for joint angulations in LLD and for the Cobb angle in AP views compared to lateral views for scoliosis. There were no clinically important biases, and most of the differences between specialists and nonspecialists were nonsignificant. The correlation between the results according to the number of bony landmarks that needed to be identified was also nonsignificant. Conclusions Digital measurements with the TraumaCad system are reliable in terms of intra-and interobserver variability, making it a useful method for the analysis of pathology on radiographs in pediatric orthopedics.

The N-terminal domain (NTD) of ␣-amino-3-hydroxy-5-methylisoxazolepropionate (AMPA) and kainate glutamate receptors plays an important role in controlling subtype specific receptor assembly. To identify NTD subdomains involved in this process we generated AMPA glutamate receptor 3 (GluR3) mutants having intra-NTD substitutions with the corresponding regions of the kainate receptor GluR6 and tested their ability to form functional heteromers with wild-type subunits. The chimeric design was based on the homology of the NTD to the NTD of the metabotropic GluR1, shown to form two globular lobes and to assemble in dimers. Accordingly, the NTD was divided into four regions, termed here N1-N4, of which N1 and N3 correspond to the regions forming lobe-1 and N2 and N4 to those forming lobe-2. Substituting N1 or N3 impaired functional heteromerization but allowed protein-protein interactions. Conversely, exchanging N2 or N4 preserved functional heteromerization, although it significantly decreased homomeric activity, indicating a role in subunit folding. Moreover, a deletion in GluR3 corresponding to the hotfoot mouse mutation of the glutamate receptor ␦2, covering part of N2, N3, and N4, impaired both homomeric and heteromeric oligomerization, thus explaining the null-like mouse phenotype. Finally, computer modeling suggested that the dimer interface, largely formed by N1, is highly hydrophobic in GluR3, whereas in GluR6 it contains electrostatic interactions, hence offering an explanation for the subtype assembly specificity conferred by this region. N3, however, is positioned perpendicular to the dimer interface and therefore may be involved in secondary interactions between dimers in the assembled tetrameric receptor.Glutamate, the major excitatory neurotransmitter, activates two receptor families: metabotropic glutamate receptors (mGluRs), 1 which are coupled to G-proteins, and ionotropic glutamate receptors (iGluRs), which form cation selective ion channels. The iGluRs are further divided into three subtypes: AMPA, kainate, and NMDA receptors, originally named after their most selective agonist (1). Each subtype, in turn, consists of several subunits that assemble as tetramers in various combinations to form channels with distinct properties (2). Of the cloned subunits, GluR1-4 form the AMPA receptors, GluR5-7 and KA1-2 form the kainate receptors, and NR1, NR2A-D, and NR3A-B form the NMDA receptors. The ␦1-2 subunits constitute an orphan group of iGluRs, and their relation to the three principal subtypes is unclear.Overall, all iGluR subunits have a common domain organization (3). Each subunit contains four membrane regions (M1-M4), of which M1, M3, and M4 traverse the plasma membrane and M2 is a reentrant loop aligning the channel pore. The N terminus is extracellular and comprises an ϳ400-residue Nterminal domain (NTD; also termed "X domain"), which is homologous to bacterial periplasmic amino acid-binding proteins and to the N-terminal domain of mGluRs (4). Following the NTD is S1, an ϳ150-residue segment, which ...

Patient satisfaction improved significantly despite no major improvement in pain, function, and range of movement of the ankle and foot. This reflects the importance of the appearance and position of the foot, and justifies the decision to undergo this long and demanding procedure.

Variants in genes encoding ribosomal proteins have thus far been associated with Diamond-Blackfan anemia, a rare inherited bone marrow failure, and isolated congenital asplenia. Here, we report one de novo missense variant and three de novo splice variants in RPL13, which encodes ribosomal protein RPL13 (also called eL13), in four unrelated individuals with a rare bone dysplasia causing severe short stature. The three splice variants (c.477þ1G>T, c.477þ1G>A, and c.477þ2 T>C) result in partial intron retention, which leads to an 18-amino acid insertion. In contrast to observations from Diamond-Blackfan anemia, we detected no evidence of significant pre-rRNA processing disturbance in cells derived from two affected individuals. Consistently, we showed that the insertion-containing protein is stably expressed and incorporated into 60S subunits similar to the wild-type protein. Erythroid proliferation in culture and ribosome profile on sucrose gradient are modified, suggesting a change in translation dynamics. We also provide evidence that RPL13 is present at high levels in chondrocytes and osteoblasts in mouse growth plates. Taken together, we show that the identified RPL13 variants cause a human ribosomopathy defined by a rare skeletal dysplasia, and we highlight the role of this ribosomal protein in bone development.

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Purpose To evaluate the temporal and spatial sequence of events following temporal hemiepiphysiodesis in idiopathic knee varus/valgus. Methods This is a retrospective multicentre study on 372 physes in 206 patients. The average rate of correction (ROC) was calculated; univariate and multivariate analysis were performed. Results In all, 92% of the femoral physes were followed for more than one year/reached skeletal maturity. Of those, 93% were corrected to a mechanical lateral distal femoral angle (mLDFA) of 85° to 89°; 2% did not, while 5% were over-corrected. A total of 92% of the tibial physes were followed for more than one year/reached skeletal maturity. Of those, 92% were corrected to a mechanical medial proximal tibial angle (mMPTA) of 85° to 89°; 2% did not, while 6% were over-corrected. Factors significantly influencing success and ROC were age, direction and magnitude of deformity. Femoral ROC was significantly faster than tibial ROC: 0.85° versus 0.78°/month, respectively (p = 0.05). Femoral valgus ROC was significantly faster than varus ROC: 0.90° versus 0.77°/month, respectively (p = 0.04). A constant was derived to calculate the amount of correction. Significant correlation was found between calculated and actual mLDFA in valgus deformity during the first year (r = 0.58 to 0.87, p < 0.01). Calculated mLDFA of varus deformity did not correlate with actual mLDFA. Significant correlation was found when calculating mMPTA correction in all deformities. Conclusions Femur corrects faster than tibia; valgus femoral deformities are corrected faster than varus. Valgus correction in the distal femur/proximal tibia as well as varus correction in the tibia in idiopathic patients is highly predictable. The constant derived is the first tool which enables predicting and monitoring amount of correction in hemiepiphysiodesis when correcting angular deformities around the knee. Level of Evidence IV