Pseudo-Protrusio Acetabular Deformity in Osteogenesis Imperfecta Patients.

BACKGROUND: Osteogenesis imperfecta (OI) can develop a protrusio acetabuli deformity. However, the authors observed a pseudo-protrusio-type acetabular deformity (PPAD) on 3-dimensional computed tomography (3D-CT). Hence, we systematically reviewed 3D-CT and pelvis radiographs of OI patients and report the incidence and patterns of acetabular deformity in OI patients and the associated radiographic signs. METHODS: The study included 590 hips of 295 OI patients, who were older than 5 years, and did not have a pelvic fracture. The incidence of a deformed acetabulum (center-edge angle >40 degrees) and its correlation with disease severity were investigated. In 40 hips for which 3D-CT was available, 3-dimensional morphology of the acetabular deformity was analyzed to delineate PPAD. On plain radiographs, PPAD-related signs were determined, focusing on the contour of ilioischial line, iliopectineal line, acetabular line, and their relationship. These radiographic signs were also evaluated in the remaining hips with deformed acetabula that did not have 3D-CT. RESULTS: One hundred twenty-three hips of 590 hips (21%) showed deformed acetabula. The incidence of deformed acetabula was significantly associated with disease severity (P<0.001). Three-dimensional analysis showed that 10 hips had protrusio acetabuli, whereas 17 had PPAD, which showed that the hemipelvis was crumpled, the acetabular roof was rotated upwardly and medially, and the hip center migrated superiorly, uncovering the anterior femoral head. Among the PPAD-related signs, superomedial bulging of the iliopectineal line was the most predictive radiographic sign (73% sensitivity and 100% specificity). This sign was also observed in almost one third of deformed acetabula of those investigated only with plain radiographs. CONCLUSIONS: This study showed that acetabular deformity is common in OI patients and is associated with disease severity. A substantial number of hips showed PPAD, which may not cause femoroacetabular impingement but result in anterior uncovering of the hip joint. Superomedial bulging of the iliopectineal line suggests this pattern of acetabular deformity. LEVEL OF EVIDENCE: Lever IV-prognostic studies.

Novel loss-of-function variants of TRAPPC2 manifesting X-linked spondyloepiphyseal dysplasia tarda: report of two cases.

BACKGROUND: X-linked spondyloepiphyseal dysplasia tarda (SEDT-XL) is a skeletal disorder characterized by defective structures of vertebral bodies and/or of epiphyses of the long bones, resulting in moderately short stature and early joint degeneration. TRAPPC2 gene, which is important for collagen secretion, has been reported as causative for SEDT-XL. CASE PRESENTATION: Here, we report two variants of TRAPPC2 gene of SEDT-XL patients, a missense variant of start codon, c.1A > T, and a deletion variant, c.40delG. To understand molecular consequence of the variants, we establish an in vitro gene expression assay system and demonstrate that both mutated genes are transcribed, but are not properly translated, indicative of the pathogenic nature of those TRAPPC2 variants. CONCLUSIONS: In the current study, we provide additional experimental data showing that loss-of-function TRAPPC2 variants are probably causative for SEDT-XL phenotype. These findings further contribute to the understanding the clinical picture related to TRAPPC2 gene.

Low-intensity pulsed ultrasound enhances callus consolidation in distraction osteogenesis of the tibia by the technique of lengthening over the nail procedure.

BACKGROUND: Low-intensity pulsed ultrasound (LIPUS) has been widely accepted in promoting the fracture healing process. However, there have been limited clinical trials focused on the efficacy of LIPUS during distraction osteogenesis (DO) by the technique of lengthening over the nail procedure. The purpose of the current study was to evaluate the efficacy of LIPUS during DO. METHODS: We retrospectively evaluated 30 patients (60 segments) who underwent simultaneous bilateral tibial lengthening over the nail. The patients were grouped into the LIPUS group and the control group based on LIPUS stimulation. The two patient groups were compared for demographic data (sex, age at operation, preoperative height, BMI, and smoking history), qualitative assessments of the callus (callus shape and type), external fixation index, and four cortical healing indexes. RESULTS: Fifteen patients (30 segments) were classified as the LIPUS group, and another 15 patients (30 segments) were classified as the control group. No significant differences were found in the assessed demographic data between the groups. LIPUS stimulated a more cylindrical, more homogenous, and denser type of callus formation at the end of the distraction phase. The two groups exhibited equivalent outcomes in terms of external fixation index (p = 0.579). However, significant differences were found in healing indexes of the anterior and medial cortices (p <  0.001 and p = 0.002, respectively). The healing indexes of those cortices in the LIPUS group (mean of 36.6 days/cm and 32.5 days/cm, respectively) reflected their significantly faster healing compared to the control group (mean HI of 57.5 days/cm and 44.2 days/cm, respectively). There were no LIPUS-related complications. CONCLUSIONS: LIPUS is a noninvasive and effective adjuvant therapy to enhance callus maturation during DO. It enhances callus consolidation and may have a positive effect on the appropriate callus shape and type.

Sustained hip flexion contracture after femoral lengthening in patients with achondroplasia.

BACKGROUND: Hip flexion contracture often occurs after femoral lengthening in patients with achondroplasia, but few studies have investigated its development in these patients. The purpose of this study was to analyze sustained hip flexion contracture in achondroplasia patients who underwent femoral lengthening and to identify contributing factors. METHODS: This study included 34 patients with achondroplasia who underwent femoral lengthening (mean age at operation, 11.1 years). Sustained hip flexion was defined as flexion contracture lasting > 6 months postoperatively despite physiotherapy. Demographic data, spinopelvic parameters (pelvic incidence, pelvic tilt, sacral slope, lumbar lordosis, and sagittal vertical axis), and quantitative assessments of femoral lengthening were investigated. The associations among these factors and the development of sustained hip flexion contracture were assessed. RESULTS: Sustained hip flexion contracture developed in 13 (38%) of 34 achondroplasia patients after femoral lengthening. Eight (62%) of these 13 patients concomitantly exhibited limitation of knee flexion. Excessive femoral lengthening (odds ratio [OR], 1.450; 95% confidence interval [CI], 1.064 to 1.975; p = 0.019) and forward sagittal vertical axis tilt (OR, 1.062; 95% CI, 1.001 to 1.127; p = 0.047) contributed to sustained hip flexion contracture. CONCLUSIONS: Sustained hip flexion contracture frequently occurs after femoral lengthening in achondroplasia patients. Both excessive femoral lengthening and preoperative forward SVA tilt may contribute to the development of sustained hip flexion contracture in these patients.

Exploring the In Vivo Anti-Inflammatory Actions of Simvastatin-Loaded Porous Microspheres on Inflamed Tenocytes in a Collagenase-Induced Animal Model of Achilles Tendinitis.

Tendon rupture induces an inflammatory response characterized by release of pro-inflammatory cytokines and impaired tendon performance. This study sought to investigate the therapeutic effects of simvastatin-loaded porous microspheres (SIM/PMSs) on inflamed tenocytes in vitro and collagenase-induced Achilles tendinitis in vivo. The treatment of SIM/PMSs in lipopolysaccharide (LPS)-treated tenocytes reduced the mRNA expressions of pro-inflammatory cytokines (Matrix metalloproteinase-3 (MMP-3), cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α)). In addition, the local injection of SIM/PMSs into the tendons of collagenase-induced Achilles tendinitis rat models suppressed pro-inflammatory cytokines (MMP-3, COX-2, IL-6, TNF-α, and MMP-13). This local treatment also upregulated anti-inflammatory cytokines (IL-4, IL-10, and IL-13). Furthermore, treatment with SIM/PMSs also improved the alignment of collagen fibrils and effectively prevented collagen disruption in a dose-dependent manner. Therefore, SIM/PMSs treatment resulted in an incremental increase in the collagen content, stiffness, and tensile strength in tendons. This study suggests that SIM/PMSs have great potential for tendon healing and restoration in Achilles tendinitis.

Comprehensive genetic exploration of skeletal dysplasia using targeted exome sequencing.

PURPOSE: The purpose of this study was to evaluate the clinical utility of targeted exome sequencing (TES) as a molecular diagnostic tool for patients with skeletal dysplasia. METHODS: A total of 185 patients either diagnosed with or suspected to have skeletal dysplasia were recruited over a period of 3 years. TES was performed for 255 genes associated with the pathogenesis of skeletal dysplasia, and candidate variants were selected using a bioinformatics analysis. All candidate variants were confirmed by Sanger sequencing, correlation with the phenotype, and a cosegregation study in the family. RESULTS: TES detected "confirmed" or "highly likely" pathogenic sequence variants in 74% (71 of 96) of cases in the assured clinical diagnosis category and 20.3% (13 of 64 cases) of cases in the uncertain clinical diagnosis category. TES successfully detected pathogenic variants in all 25 cases of previously known genotypes. The data also suggested a copy-number variation that led to a molecular diagnosis. CONCLUSION: This study demonstrates the feasibility of TES for the molecular diagnosis of skeletal dysplasia. However, further confirmation is needed for a final molecular diagnosis, including Sanger sequencing of candidate variants with suspected, poorly captured exons.Genet Med 18 6, 563-569.

Developmental pattern of the hip in patients with hereditary multiple exostoses.

BACKGROUND: Coxa valga is a common clinical feature of hereditary multiple exostoses (HME). The current study aimed to determine the unique developmental pattern of the hip in patients with HME and evaluate the factors that influence its progression. METHODS: Thirty patients (57 hips) with HME were divided into two groups according to the Hilgenreiner epiphyseal angle (HEA). Twenty-two patients (44 hips) including 13 men and 9 women were assigned to group 1 (HEA <25°), and 8 patients (13 hips) including 3 men and 5 women were assigned to group 2 (HEA ≥25°). The mean age at the initial presentation was 6.0 (4-12) years with 6.8 (4-11) years of follow-up in group 1, and 10.4 (8-13) years with 5.4 (2-9) years of follow-up in group 2. We measured the HEA, neck-shaft angle (NSA), acetabular index (AI), center-edge angle (CEA), and migration percentage (MP) for radiographic evaluation. RESULTS: Among the hips, 50 (87.7%) hips had coxa valga and 27 (47.4%) hips had abnormal MP (42.1% were borderline and 5.3% were subluxated). There was a significant difference in the HEA and NSA between the groups (p < 0.001 and p < 0.05, respectively). The HEA significantly correlated with the development of the NSA and no correlation was found between the HEA and AI, CEA, and MP. CONCLUSIONS: There was a significant relationship between the HEA at the initial presentation and the NSA at skeletal maturity. We should consider guided growth for patients with lower HEA to prevent significant coxa valga deformity with close follow-up.

The Effect of Alendronate Loaded Biphasic Calcium Phosphate Scaffolds on Bone Regeneration in a Rat Tibial Defect Model.

This study investigated the effect of alendronate (Aln) released from biphasic calcium phosphate (BCP) scaffolds. We evaluated the in vitro osteogenic differentiation of Aln/BCP scaffolds using MG-63 cells and the in vivo bone regenerative capability of Aln/BCP scaffolds using a rat tibial defect model with radiography, micro-computed tomography (CT), and histological examination. In vitro studies included the surface morphology of BCP and Aln-loaded BCP scaffolds visualized using field-emission scanning electron microscope, release kinetics of Aln from BCP scaffolds, alkaline phosphatase (ALP) activity, calcium deposition, and gene expression. The in vitro studies showed that sustained release of Aln from the BCP scaffolds consisted of porous microstructures, and revealed that MG-63 cells cultured on Aln-loaded BCP scaffolds showed significantly increased ALP activity, calcium deposition, and gene expression compared to cells cultured on BCP scaffolds. The in vivo studies using radiograph and histology examination revealed abundant callus formation and bone maturation at the site in the Aln/BCP groups compared to the control group. However, solid bony bridge formation was not observed at plain radiographs until 8 weeks. Micro-CT analysis revealed that bone mineral density and bone formation volume were increased over time in an Aln concentration-dependent manner. These results suggested that Aln/BCP scaffolds have the potential for controlling the release of Aln and enhance bone formation and mineralization.

Whole-exome sequencing identifies mutations of KIF22 in spondyloepimetaphyseal dysplasia with joint laxity, leptodactylic type.

Spondyloepimetaphyseal dysplasia with joint laxity (SEMDJL), leptodactylic (lepto-SEMDJL) or Hall type, is an autosomal-dominant skeletal dysplasia manifesting with short stature, joint laxity with dislocation(s), limb malalignment, and spinal deformity. Its causative gene mutation has not yet been discovered. We captured and sequenced the exomes of eight affected individuals in six unrelated kindreds (three individuals in a family and five simplex individuals). Five novel sequence variants in KIF22, which encodes a member of the kinesin-like protein family, were identified in seven individuals. Sanger sequencing of KIF22 confirmed that c.443C>T (p.Pro148Ser) cosegregated with the phenotype in the affected individuals in the family; c.442C>T (p.Pro148Leu) or c.446G>A (p.Arg149Gln) was present in four of five simplex individuals, but was absent in unaffected individuals in their family and 505 normal cohorts. KIF22 mRNA was detected in human bone, cartilage, joint capsule, ligament, skin, and primary cultured chondrocytes. In silico analysis of KIF22 protein structure indicates that Pro148 and Arg149 are important in maintaining hydrogen bonds in the ATP binding and motor domains of KIF22. We conclude that these mutations in KIF22 cause lepto-SEMDJL.

Complications of the Intramedullary Skeletal Kinetic Distractor (ISKD) in distraction osteogenesis.

BACKGROUND: The Intramedullary Skeletal Kinetic Distractor (ISKD) (Orthofix Inc, Lewisville, TX, USA) is an intramedullary device designed for more comfortable limb lengthening than that with external fixators; lengthening is achieved with this nail using rotational oscillation between two telescoping sections. However, the degree to which this device achieves this goal and its complication rate have not been fully documented. QUESTIONS/PURPOSES: We determined (1) the frequency with which distraction was not achieved at the desired rate, (2) whether pain differed between patients with normally and abnormally distracting nails, (3) risk factors for abnormal nails, and (4) other complications. METHODS: We analyzed 35 lengthening segments (26 femurs, nine tibias) in 19 patients. Mean length achieved was 47 mm. Femoral nails were categorized into four groups according to distraction rate: normal, runaway (unintentionally faster rate [> 1.5 mm/day]), difficult-to-distract (slower rate [< 0.8 mm/day] requiring manual manipulation but not requiring general anesthesia), and nondistracting (slower rate [< 0.8 mm/day] requiring manual manipulation under general anesthesia or reosteotomy). Possible risk factors, including age, BMI, preoperative thigh circumferences, degree of intramedullary overreaming, and length of the thicker portion of the nail within the distal fragment, were compared among groups. VAS pain scores were compared among groups under three conditions: rest, physiotherapy, and distraction motion. Complications were also analyzed. Minimum followup was 15 months (mean, 26 months; range, 15-38 months) after first-stage surgery. RESULTS: Abnormal distraction rate was observed in 21 of 35 segments (60%; 17 femurs, four tibias). VAS pain scores showed no differences among groups during rest or physiotherapy but were higher (p = 0.02) in the problematic nails (7-8 points) versus normal nails (3 points) during distraction. Only mean length of the thicker portion of the nail within the distal fragment differed between normally and abnormally distracting nails (95 mm versus 100 mm; p = 0.03), although this was unlikely to be clinically important. Complications occurred in 10 patients (53%), including five with decreased ankle ROM during distraction, four with delayed bone healing, and one with mechanical device failure during distraction. CONCLUSIONS: Rate control was difficult to achieve with the ISKD nail for femoral and tibial lengthenings, complications were relatively common, and among patients in whom rate control was not achieved, pain levels were high. Based on our findings, we believe that surgeons should avoid use of this nail. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Comparison of orthopaedic manifestations of multiple epiphyseal dysplasia caused by MATN3 versus COMP mutations: a case control study.

BACKGROUND: Multiple epiphyseal dysplasia (MED) is a relatively common skeletal dysplasia mainly involving the epiphyses of the long bones. However, it is a genetically heterogeneous group of diseases sharing certain aspects of the radiologic phenotype. In surveys conducted in East Asia, MATN3 was the most common causative gene, followed by COMP. In this study, the authors compared clinical manifestation of MED patients caused by MATN3 and COMP gene mutations, as well as subsequent orthopaedic interventions. METHODS: Fifty nine molecularly-confirmed MED patients were subjects of this study. The MATN3 gene mutation group comprised of 37 patients (9 female, 28 male). The COMP gene mutation consisted of 22 cases (15 females, 7 males). Medical records and radiographs were reviewed, and questionnaire surveys or telephone interviews were conducted. RESULTS: At the first presentation, the mean age was 8.8 ± 2.8 years (mean ± standard deviation) in the MATN3 group, and 8.5 ± 3.5 years in the COMP group (p = 0.670). The height in the COMP group was significantly shorter than those in the MATN3 group (p < 0.001). Gait abnormality at the first visit (p = 0.041) and the lastest follow-up (p = 0.037) were statistically significant difference. Hip pain (p = 0.084), limitation of daily activity (p = 0.075) at the latest follow-up tended to be more frequent in the COMP group. Hip dysplasia was more common in the COMP group, having significantly larger acetabular angle (p = 0.037), smaller center-edge angle (p = 0.002), severe Stulberg classification (p < 0.001), and smaller femoral head coverage (p < 0.001). CONCLUSIONS: Clinical manifestations of MED caused by MATN3 were milder than manifestations of the COMP mutation group. These differences in clinical manifestation and prognosis justify molecular differentiation between the two genotypes.

Xenotransplantation of human mesenchymal stem cells for repair of osteochondral defects in rabbits using osteochondral biphasic composite constructs.

PURPOSE: The aim of this work is to investigate the feasibility of non-autologous transplantation of human mesenchymal stem cells (hMSCs) with or without differentiation for the regeneration of osteochondral defects in rabbits using a biphasic composite construct composed of platelet-rich fibrin glue (PR-FG) and hydroxyapatite. METHODS: After isolation and culture, hMSCs were seeded on biphasic composite constructs (hydroxyapatite + PR-FG) and transplanted into osteochondral defects of adult New Zealand white rabbits. Treatment of individual defects was applied by random assignment to one of five groups: (1) control, defects untreated; (2) hydroxyapatite, defects filled with hydroxyapatite only; (3) hydroxyapatite + PR-FG, defects filled with a composite of hydroxyapatite and PR-FG; (4) hydroxyapatite + PR-FG + undifferentiated hMSCs; and (5) hydroxyapatite + PR-FG + differentiated hMSCs. Rabbits were killed at 4 or 8 weeks post-surgery, at which time osteochondral repair was macroscopically and histologically evaluated and scored using the modified International Cartilage Repair Society scoring system. RESULTS: The group in which defects were seeded with differentiated hMSCs (group 5) showed superior healing of osteochondral defects based on macroscopic and histological observations compared to other groups. Specifically, 8 weeks after implantation, defects were filled with more hyaline-like cartilage and were better integrated with the surrounding native cartilage. The histological scores were significantly better than those of other groups (16.3 at 8 weeks, p < 0.01). CONCLUSION: Xenogeneic transplantation of differentiated hMSCs using a biphasic composite construct effectively repaired osteochondral defect in a rabbit model. Differentiated hMSCs showed superior healing of chondral lesion to undifferentiated hMSCs.

Assessment of skeletal age in multiple epiphyseal dysplasia.

BACKGROUND: Determining the skeletal age in patients with multiple epiphyseal dysplasia (MED) is essential for predicting the adult height and guiding the timing of limb lengthening, epiphysiodesis, and other surgical procedures. In the present study, we examined the patterns of skeletal age delay using 3 different methods, the Greulich-Pyle (GP) atlas method, the Tanner-Whitehouse 3 (TW3) method using radius-ulna-short bones (RUS) scoring system, and the TW3 method using the carpal bone maturity scoring system. METHODS: Left hand radiographs from 23 patients (age range, 3 to 14 y) with MED were examined to determine the skeletal age. We examined the reliability of the 3 different methods and evaluated the difference between the chronological age and the skeletal age. RESULTS: The interobserver and intraobserver reliabilities were higher with the GP atlas method and the TW3 RUS method compared with the TW3 carpal bone maturity scoring system. There was significant skeletal age delay irrespective of the method used (P<0.01). When we used the TW3 carpal method, the pattern of skeletal age delay was significantly distinct from the other 2 methods. According to the measurement method, there was no statistically significant difference in the developmental skeletal age pattern among the COMP gene group, the MATN3 gene group, and other gene groups. CONCLUSIONS: Our findings indicate that there is a distinct skeletal maturation pattern in patients with MED. The skeletal age is relatively delayed compared with the chronological age irrespective of the measuring method utilized. However, use of either the GP atlas or the TW3 RUS method provided more accurate information on the skeletal development in the patients with MED than that provided by the TW3 carpal bone maturity scoring system. LEVEL OF EVIDENCE: Level I. Diagnostic study.

Timing of premature physeal closure in Legg-Calve-Perthes Disease.

PURPOSE: Premature physeal closure of the proximal femoral physis has been reported in Legg-Calve-Perthes Disease (LCPD). However, the timing of its occurrence had not yet been reported. We proposed (1) to determine the timing of premature physeal closure in unilateral LCPD with serial radiographic evaluation, and (2) to evaluate the relationship between the premature physeal closure and Herring classification, leg-length discrepancy (LLD), Stulberg classification, and trochanteric overgrowth. METHODS: We performed a retrospective study with serial radiographs of 27 patients diagnosed with LCPD. The difference in the timing of physeal closure between the hips was calculated. The involved hip was classified according to Herring classification. The LLD and ATD index at latest follow up was measured. The mean values were calculated and statistical comparison of variables was done using the Fisher's exact test. RESULTS: The mean difference of physeal closure at the involved hip compared to the uninvolved side was 3.5 years (range, two to five years). Hips demonstrating premature physeal closure were associated with Herring B/C and C (p = 0.01) and LLD >1 cm (p = 0.02). There is no correlation between Stulberg classification, trochanteric overgrowth and premature physeal closure (p = 0.06 and p = 0.19). CONCLUSIONS: We may expect premature physeal closure of the proximal femoral physis in patients with LCPD to occur 3.5 years earlier than normal hips. Presence of premature physeal closure can be an adjunct diagnostic tool in the prognostication of LCPD outcomes. Future studies directed toward premature physeal closure in LCPD and associated growth disturbances are necessary.

Extent of physeal involvement in Legg-Calvé-Perthes disease.

PURPOSE: The growth plate involvement (GPI) index is reportedly a reliable predictor of final radiographic outcome in Legg-Calvé-Perthes disease (LCPD). We determined whether (1) the GPI index was associated with the lateral pillar classification, (2) the GPI index could predict the final radiographic outcome, and (3) the geometry of proximal femur was affected by presence of physeal involvement. METHODS: We reviewed 47 patients with unilateral LCPD who were treated conservatively. The mean duration of follow-up was 9.5 years (range, five to 13 years). The affected hips were categorized into those with and without physeal involvement. Herring classifications were determined and the GPI indices were estimated at the stage of maximum fragmentation. The Stulberg classification, leg length discrepancy (LLD), articulotrochanteric distance (ATD) index, neck-shaft angle (NSA), neck width and height were determined at skeletal maturity. RESULTS: The GPI indices were lower in Herring groups A and B (p < 0.001) and Stulberg classes I and II (p = 0.002), and these values were increased in the Herring group B/C and C and Stulberg classes III, IV and V. However, the age of onset, LLD and ATD index at skeletal maturity were not associated with the GPI index. The NSA of the affected hips with physeal involvement was significantly different compared to that of unaffected hips (p < 0.001). CONCLUSIONS: The GPI index could be used to determine the extent of physeal involvement in LCPD, and might be considered one of the prognostic values of radiographic development in patients with LCPD who are treated conservatively.

Clinical implication of sagittal translation in lengthening over nail of tibia.

PURPOSE: During the surgery of lengthening over nail (LON), we sometimes observe sagittal translation of proximal tibia (STPT) when the nail is inserted into the canal. We investigated the factors that lead to STPT and its clinical significance. METHODS: We reviewed 35 consecutive patients who underwent bilateral tibial lengthening with LON. The following parameters were assessed to evaluate the factors that can lead to STPT; the level of tibia osteotomy (OT) in sagittal plane, the type of the nail, the nail entry point in sagittal/coronal planes, and the type of the OT. Then, the followings are analyzed to find any possible clinical significance of this phenomenon: the change of posterior proximal tibial angle (PPTA), the cortical healing index, and the translation of the sagittal mechanical axis (SMA) of the lower extremity. RESULTS: The postoperative STPT was 3.04 ± 2.73 mm, and proximal location of the OT in relation to the nail bending point was found to increase STPT. The nail entry point in sagittal/coronal planes and the type of tibia OT had no significant correlations with STPT. It had no significant relations with the PPTA or cortical healing index. It pushed the SMA posteriorly, but the SMA was always anterior to the center of rotation of the knee joint. CONCLUSIONS: Proximal location of the OT in relation to the nail bending point is related to STPT. However, it does not negatively influence cortical healing, posterior tibial slope, or SMA of the lower extremity.

HDA19 is required for the repression of salicylic acid biosynthesis and salicylic acid-mediated defense responses in Arabidopsis.

To cope with a lifetime of exposure to a variety of pathogens, plants have developed exquisite and refined defense mechanisms that vary depending on the type of attacking pathogen. Defense-associated transcriptional reprogramming is a central part of plant defense mechanisms. Chromatin modification has recently been shown to be another layer of regulation for plant defense mechanisms. Here, we show that the RPD3/HDA1-class histone deacetylase HDA19 is involved in the repression of salicylic acid (SA)-mediated defense responses in Arabidopsis. Loss of HDA19 activity increased SA content and increased the expression of a group of genes required for accumulation of SA as well as pathogenesis related (PR) genes, resulting in enhanced resistance to Pseudomonas syringae. We found that HDA19 directly associates with and deacetylates histones at the PR1 and PR2 promoters. Thus, our study shows that HDA19, by modifying chromatin to a repressive state, ensures low basal expression of defense genes, such as PR1, under unchallenged conditions, as well as their proper induction without overstimulation during defense responses to pathogen attacks. Thus, the role of HDA19 might be critical in preventing unnecessary activation and self-destructive overstimulation of defense responses, allowing successful growth and development.

Upper torso and pelvis linear velocity during the downswing of elite golfers.

BACKGROUND: During a golf swing, analysis of the movement in upper torso and pelvis is a key step to determine a motion control strategy for accurate and consistent shots. However, a majority of previous studies that have evaluated this movement limited their analysis only to the rotational movement of segments, and translational motions were not examined. Therefore, in this study, correlations between translational motions in the 3 axes, which occur between the upper torso and pelvis, were also examined. METHODS: The experiments were carried out with 14 male pro-golfers (age: 29 ± 8 years, career: 8.2 ± 4.8years) who registered in the Korea Professional Golf Association (KPGA). Six infrared cameras (VICON; Oxford Metrics, Oxford, UK) and SB-Clinc software (SWINGBANK Ltd, Korea) were used to collect optical marker trajectories. The center of mass (CoM) of each segment was calculated based on kinematic principal. In addition, peak value of CoM velocity and the time that each peak occurred in each segment during downswing was calculated. Also, using cross-correlation analysis, the degree of coupling and time lags of peak values occurred between and within segments (pelvis and upper torso) were investigated. RESULTS: As a result, a high coupling strength between upper torso and pelvis with an average correlation coefficient = 0.86 was observed, and the coupling between segments was higher than that within segments (correlation coefficient = 0.81 and 0.77, respectively). CONCLUSIONS: Such a high coupling at the upper torso and pelvis can be used to reduce the degree of motion control in the central nervous system and maintain consistent patterns in the movement. The result of this study provides important information for the development of optimal golf swing movement control strategies in the future.

Can residual leg shortening be predicted in patients with Legg-Calvé-Perthes' disease?

BACKGROUND: Although Legg-Calvé-Perthes' disease (LCPD) is frequently associated with varying degrees of femoral head deformity and leg length discrepancy (LLD), no factors that predict residual shortening have been clearly identified. QUESTIONS/PURPOSES: We attempted to determine whether (1) the extent of femoral head involvement; (2) varus osteotomy; and (3) patient demographic characteristics are associated with LLD at skeletal maturity in patients with LCPD. METHODS: We retrospectively reviewed the records of 168 skeletally mature patients with unilateral LCPD. The mean age at diagnosis was 7 years (range, 2-14 years). The extent of femoral head involvement was determined from the initial radiographs using the Herring lateral pillar and Catterall classifications. LLD was defined as shortening by ≥ 1.0 cm as measured from scanograms. The patient's sex and the treatment modalities used were also recorded. RESULTS: LLD ranging from 10 to 38 mm (mean, 19 mm) occurred in 93 (55%) patients and was associated with the extent of femoral head involvement. Varus osteotomy was not associated with residual shortening. The patient's age at diagnosis did not affect the LLD at skeletal maturity. The strongest predictor of LLD was a lateral pillar classification of B/C or C (odds ratio, 3.5; 95% confidence interval, 1.39-8.79). CONCLUSIONS: The extent of femoral head involvement, but not the patient's age at diagnosis or sex or the treatment modality, can predict the LLD at skeletal maturity in patients with unilateral LCPD.

How reliable are standard radiographic measures of the foot and ankle in children with achondroplasia?

BACKGROUND: Radiographic measurements are typically used in achondroplasia (ACH) during correction of lower limb alignment. However, reliabilities for the measurements on weightbearing radiographs of the foot and ankle in patients with ACH have not been described, and the differences between the ACH population and subjects without ACH likewise have not been well characterized; these issues limit the use of studies on this subject. QUESTIONS/PURPOSES: We proposed (1) to measure the inter- and intraobserver reliability of a number of radiographic measures of ankle and foot alignment in an achondroplastic cohort of patients; and (2) to compare our radiographic measurement values with age-matched literature-based normative values. METHODS: Ten radiographic measurements were applied to foot and ankle radiographs of 20 children (40 feet) with ACH (mean age, 10 years; range, 8-16 years). Interobserver and intraobserver reliabilities of these radiographic measurement methods were obtained and expressed by intraclass correlation coefficients (ICCs). The mean values were calculated and compared with the literature-based values. RESULTS: The interobserver reliability was excellent for eight measurements with ICCs ranging from 0.801 to 0.962, except for lateral talo-first metatarsal angle and mediolateral column ratio, which were much lower. The intraobserver reliability was excellent for all 10 radiographic measurements with ICCs ranging from 0.812 to 0.998. Compared with existing literature-based values, all 10 measurements had a significant difference (p < 0.01). CONCLUSIONS: We suggest tibiotalar angle, calcaneal pitch angle, tibiocalcaneal angle, talocalcaneal angle, naviculocuboid overlap, talonavicular coverage angle, metatarsal stacking angle, and AP talo-first metatarsal angle with excellent interobserver and intraobserver reliabilities should be considered preferentially in analysis of foot and ankle alignment in children with ACH.