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BackgroundBilateral internal rotation gait is a common gait abnormality in children with bilateral cerebral palsy, but still not fully understood.Research questionThe aim of this clinical study was to analyze the effects of artificially induced bilateral internal rotation gait on kinematics and kinetics. Our hypothesis was, that the internal rotation gait defined as increased dynamic internal hip rotation itself causes significant alterations in gait kinematics and kinetics.Methods30 typically developing children with a mean age of 12 (SD 3) years (range 8 – 16) performed three-dimensional gait analysis in two different conditions: with unaffected gait and with artificially induced bilateral internal rotation gait with two rotation bandages worn in order to internally rotate the hips. Kinematic and kinetic changes between these two conditions were calculated and compared using a mixed linear model with “gait condition” as fixed effect and both “limb” and “patient” as random effects.ResultsThe rotation bandages induced a significant increase in internal hip rotation and foot progression angle towards internal without affecting pelvic rotation. The peak hip internal rotator moment during loading response and the peak hip external rotator moment during the first half of stance phase increased significantly and the peak hip internal rotator moment during the second half of stance phase decreased significantly. Anterior pelvic tilt, hip flexion, knee flexion and ankle dorsiflexion increased significantly. The first peak of the frontal hip moment decreased, and the second increased significantly. The second peak of the frontal knee moment decreased significantly, while the first didn’t change significantly.SignificanceThe data suggest, that the bilaterally increased dynamic internal hip rotation itself has a relevant impact on frontal hip moments. The increased anterior pelvic tilt, hip and knee flexion may be either induced by the pull of the rotation bandage or a secondary gait deviation.  相似文献   
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Objective

The aim of the study was to evaluate the loss of truncal rotation over 54 hours after removing Chêneau brace.

Methods

The studied groups consisted of 39 girls aged 10–18 years old, diagnosed with adolescent idiopathic scoliosis (AIS) and treated with Chêneau brace (CAST) and 20 AIS girls aged 10–18 years old, not treated with bracing. Posterior-anterior radiographs were obtained from the clinical assessment of all subjects and were subsequently used to determine Cobb angles. The measurements of the angle of trunk rotation (ATR) were taken with the Scoliometer® and back-contour device during Adams forward bending test by the two evaluators. The changes in ATRs during 54 hours of observation were performed after the brace had been taken off (0, 2, 24, 30, 48 and 54 hours after debracing). This was described using VATR variable, defined as the change in the absolute Scoliometer® readings in the time intervals against the time interval Δt between the measurements. During back-contour assessment the differential factor (kra) has been used for the digital analysis. The changes in kra over 54 hours of observation were expressed as Vkra factor, defined as the difference in the absolute value of the amplitude differential factor (kra) in the time intervals against the time interval Δt between the measurements.

Results

The highest changes were observed in the thoracic as well as in lumbar spine in patients with Cobb angle ≥30°, axial rotation of the apical vertebrae within 5–15°, Risser sign 0–2. The biggest change in the trunk rotation after Chêneau brace had been taken off was noted within the first two hours of observation.

Conclusion

The patients should be advised to take the brace off for a minimum of two hours before the scheduled x-ray, to allow full relaxation of the trunk in order to obtain reliable radiological images of the deformation.

Level of Evidence

Level III Therapeutic study.  相似文献   
6.

Introduction

The aim of this study was to evaluate the root canal shaping effect of instruments manufactured from nickel titanium, M-Wire, and Gold wire with different glide path preparation techniques.

Methods

One hundred thirty-five mesiobuccal canals of extracted human maxillary molars were randomly divided into 3 equal groups (N = 45) for glide path preparation with K-files (KF) (Dentsply Sirona, Ballaigues, Switzerland), One G (OG) files (Micro-Mega, Besançon, France), and ProGlider (PG) files (Dentsply Sirona). Specimens of each glide path group were further divided equally into 3 groups for instrumentation with ProTaper Next (PTN, Dentsply Sirona), One Shape (OS, Micro-Mega), and WaveOne Gold (WOG, Dentsply Sirona) systems (n = 15). Micro–computed tomographic imaging was used to scan teeth before instrumentation and after shaping to compare centering ratio and canal transportation values at the apical, midroot, and coronal levels and the overall changes in canal volume. Data sets were statistically analyzed (analysis of variance and Kruskal-Wallis H tests).

Results

The centering ratios for all groups were statistically similar at all levels. Apical canal transportation was significantly high for K/OS and K/PTN (P = .003). Midroot canal transportation was significantly high for K/PTN, K/OS, and OG/OS (P = .0003). Coronal canal transportation was significantly high for K/PTN and K/OS (P = .011). The highest change in canal volume was observed with all PTN groups and the lowest with PG/WOG (P = .06).

Conclusions

WOG manufactured from Gold wire combined with PG showed better root canal shaping ability and removed less dentin from the canal walls. The nickel-titanium (OS) and M-Wire (PTN) instruments used in combination with KF significantly transported more canals. PTN removed the most dentin from the canal walls regardless of the GPP technique.  相似文献   
7.
Spatial representations are processed in the service of several different cognitive functions. The present study capitalizes on the Activation Likelihood Estimation (ALE) method of meta‐analysis to identify: (a) the shared neural activations among spatial functions to reveal the “core” network of spatial processing; (b) the specific neural activations associated with each of these functions. Following PRISMA guidelines, a total of 133 fMRI and PET studies were included in the meta‐analysis. The overall analysis showed that the core network of spatial processing comprises regions that are symmetrically distributed on both hemispheres and that include dorsal frontoparietal regions, presupplementary motor area, anterior insula, and frontal operculum. The specific analyses revealed the brain regions that are selectively recruited for each spatial function, such as the right temporoparietal junction for shift of spatial attention, the right parahippocampal gyrus, and the retrosplenial cortex for navigation and spatial long‐term memory. The findings are integrated within a systematic review of the neuroimaging literature and a new neurocognitive model of spatial cognition is proposed.  相似文献   
8.
IntroductionLatarjet procedure is commonly performed for recurrent anterior shoulder instability with glenoid side bone loss. Classic Latarjet procedure can be performed using specially designed drill guides, jigs, or by freehand technique. Here we have described a technical note on classic Latarjet procedure performed with freehand technique utilizing simple rulers and caliper. The functional and radiological outcomes of our patients have also been analysed.Material and Methods149 open classic Latarjet procedures were performed using our technique between March 2015 and July 2018. The mean age of the patients was 32.95 years (Range 22–59 years). The functional outcome of the patients was measured using Western Ontario Shoulder Instability (WOSI) and Oxford Shoulder Instability Score (OSIS) at 2 years of follow-up. Screw and graft positioning were studied in 24 consecutive patients with a postoperative computed tomography (CT) scan.ResultsThere was no incidence of recurrent subluxation or dislocation post-surgery. Mean OSIS score increased from 15.63 ± 3.20 preoperatively to 42.44 ± 3.88 postoperatively (p value < 0.05). WOSI score decreased significantly from 62.54% ± 8.24 to 10.26 ± 6.33 postoperatively at 2-year follow-up (p value < 0.05). Postoperative CT scan also showed satisfactory screw placement in all patients.ConclusionOpen Latarjet procedure performed using freehand technique provides good functional and radiological outcomes in patients with recurrent anterior shoulder instability with glenoid side bone loss.Supplementary InformationThe online version contains supplementary material available at 10.1007/s43465-021-00385-7.  相似文献   
9.
BackgroundSurgical planning of posterior referencing total knee arthroplasty (TKA) using computed tomography (CT) might lead to over-rotation of the femoral component because CT could not detect cartilage thickness of the posterior femoral condyle. The purpose of this study was to examine the rotational alignment difference of the femoral component between magnetic resonance imaging (MRI) and CT.MethodsFor elderly varus osteoarthritic patients, 66 varus osteoarthritic knee patients that underwent primary TKA were selected. Twenty-seven young patients who underwent primary anterior cruciate ligament reconstruction were selected as control. After the transepicondylar axis (CEA), the surgical epicondylar axis (SEA) and the posterior femoral condylar line (PCL) were drawn on CT and on MRI at the same angles as CT. Then, the practical PCL was drawn on MRI considering the cartilage thickness (the cartilage PCL). The angle between the SEA and the cartilage PCL (the cartilage posterior condylar angle (PCA)) was measured as preoperative planning. To investigate the accuracy of preoperative MRI measurement, the cartilage thickness on posterior femoral condyles was directly measured during TKA.ResultsThe cartilage PCA for varus osteoarthritic patients averaged 1.3 ± 1.3°. The cartilage PCA was 1.8 ± 1.0° significantly smaller than the bone PCA (the PCA measured on CT). Meanwhile, the cartilage PCA was 0.2 ± 0.4° significantly larger than the bone PCA in young people. The preoperative angle measurement on MRI strongly correlated with the direct measurement of cartilage thickness during TKA.ConclusionThere was 1.8° of divergence between MRI and CT in varus osteoarthritic patients due to cartilage degeneration of the medial femoral condyle. Cartilage assessment using MRI was useful for femoral component rotational alignment.  相似文献   
10.

Background context

The surgical treatment of degenerative disc disease at the lumbar spine may involve fusion. Total disc replacement (TDR) is an alternative treatment to avoid fusion-related adverse events, specifically adjacent segment disease. New generation of elastomeric non-articulating devices has been developed to more effectively replicate the shock absorption and flexural stiffness of native disc.

Purpose

To report 5 years clinical and radiographic outcomes, range of motion (ROM), and position of the center of rotation after a viscoelastic lumbar TDR.

Study Design

Prospective observational cohort study

Patient sample

Sixty-one patients

Outcome Measures

The clinical evaluation was based on visual analog scale (VAS) for pain, Oswestry disability index (ODI) score, short form-36 (SF-36) including the physical component summary (PCS) and the mental component summary (MCS), and general health questionnaire-28 (GHQ28). The radiological outcomes were ROM and position of the center of rotation at the index and the adjacent levels and the adjacent disc height changes.

Methods

Our study group included 61 consecutive patients with monosegmental disc replacement. We selected patients who could provide a global lumbar spine mobility analysis (intermediate functional activity according to the Baecke score). Hybrid constructs had been excluded. Only the cases with complete clinical and radiological follow-up at 3, 6, 12, 24, and 60 months were included.

Results

There was a significant improvement in VAS (3.3±2.5 vs. 6.6±1.7, p<.001), in ODI (20±17.9 vs. 51.2±14.6, p<.001), GHQ28 (52.6±15.5 vs. 64.2±15.6, p<.001), SF-36 PCS (58.8±4.8 vs. 32.4±3.4, p<.001), and SF-36 MCS (60.7±6 vs. 42.3±3.4, p<.001). The mean location centers of the index level and adjacent discs were comparable to those previously published in asymptomatic patients. According to the definition of Zigler and Delamarter, all of our cases remained grade 0 for adjacent level disc height (within 25% of normal).

Conclusions

This series reports significant improvement in midterm follow-up after TDR, which is consistent with previously published studies but with a lower rate of revision surgery and no adjacent level disease pathologies. The radiographic assessment of the patients demonstrated the quality of functional reconstruction of the lumbar spine after LP-ESP viscoelastic disc replacement.  相似文献   
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