Intervertebral disc degeneration involves changes in its material properties that affect the mechanical functions of the spinal system. However, the alteration of the biomechanics of a spinal segment through specific material degradation in a specific region is poorly understood. In this study, the influence of the constitutive material degeneration of disc tissues on the mechanics of a lower lumbar spinal unit was examined using a three-dimensional nonlinear finite element model of the L4-L5 functional spinal unit. Different grades of disc degeneration were simulated by introducing a degeneration factor to the corresponding material properties to represent fibrous nucleus, increased fibre and ground substance laxity, increased fibre stiffness and total annular fracture along posterior and posterolateral regions. The model was loaded with an axial compression of 500 N and pure moments of up to 10 Nm to simulate extension, flexion, lateral bending and axial rotation. To validate the model, the spinal motion and intradiscal pressure of healthy and degenerated discs with existing in vitro data were compared. The disc with a fibrous nucleus and the presence of intradiscal pressure increase the spinal instability during flexion and axial rotation, and the absence of intradiscal pressure increases the spinal instability in all directions. Bulging displacement and shear strains in the disc with total fracture and ground substance laxity are high in all of the loading cases. Our study could provide useful information to enhance our understanding of the influence of each constitutive component of the intervertebral disc on the mechanics of the spinal segment.
Matched MeSH terms: Range of Motion, Articular/physiology
Patient movement during Magnetic Resonance Imaging (MRI) scan can cause severe degradation of image quality. In Susceptibility Weighted Imaging (SWI), several echoes are typically measured during a single repetition period, where the earliest echoes show less contrast between various tissues, while the later echoes are more susceptible to artifacts and signal dropout. In this paper, we propose a knowledge interaction paradigm that jointly learns feature details from multiple distorted echoes by sharing their knowledge with unified training parameters, thereby simultaneously reducing motion artifacts of all echoes. This is accomplished by developing a new scheme that boosts a Single Encoder with Multiple Decoders (SEMD), which assures that the generated features not only get fused but also learned together. We called the proposed method Knowledge Interaction Learning between Multi-Echo data (KIL-ME-based SEMD). The proposed KIL-ME-based SEMD allows to share information and gain an understanding of the correlations between the multiple echoes. The main purpose of this work is to correct the motion artifacts and maintain image quality and structure details of all motion-corrupted echoes towards generating high-resolution susceptibility enhanced contrast images, i.e., SWI, using a weighted average of multi-echo motion-corrected acquisitions. We also compare various potential strategies that might be used to address the problem of reducing artifacts in multi-echoes data. The experimental results demonstrate the feasibility and effectiveness of the proposed method, reducing the severity of motion artifacts and improving the overall clinical image quality of all echoes with their associated SWI maps. Significant improvement of image quality is observed using both motion-simulated test data and actual volunteer data with various motion severity strengths. Eventually, by enhancing the overall image quality, the proposed network can increase the effectiveness of the physicians' capability to evaluate and correctly diagnose brain MR images.
Monteggia fracture is commonly treated with open anatomical reduction and fixation of the ulna fracture. The radial head will be automatically reduced once anatomical fixation of the ulna is achieved. However, it is occasionally associated with an irreducible radial head dislocation requiring an open reduction and reconstruction of the torn annular ligament. We describe a case of traumatic Monteggia fracture which underwent initial plating, however post-operative radiograph denoted an irreducible radial head secondary to a ruptured annular ligament. We reconstructed the annular ligament with a synthetic graft sling around the radial neck with an anchor suture. The radial head was stable in all directions after annular ligament reconstruction. A two-year follow-up shows full range of motion of the elbow joint with osteolysis of the radial head, no other operative morbidity was observed.
Introduction This appears to be the first biomechanical study that compares the stability of various locations of the crossing points in crossed pinning Kirschner wiring (K-wire) construct in treating pediatric supracondylar humerus fracture (SCHF). Additionally, this study compared the biomechanical stability between crossed pinning K-wire construct and the three-lateral divergent K-wire construct. Methods For the study purpose, 30 synthetic humerus bones were osteotomised at mid-olecranon fossa, anatomically reduced, and pinned using two 1.6-millimeter K-wires in five different constructs. A total of six samples were prepared for each construct and tested for extension, flexion, valgus, varus, internal rotation, and external rotation forces. Results As for crossed pinning K-wire construct, the center crossing point emerged as the stiffest construct in both linear and rotational forces, in comparison to the lateral crossing point, superior crossing, and medial crossing point Conclusion Based on this analysis, it is highly recommended that, if the crossed pinning construct is selected to treat supracondylar humerus fracture, the surgeon should aim for center crossing point as it is the most stable construct. Nevertheless, if lateral and superior crossing points are obtained during the initial attempt of fixation, the fixation may be accepted without revising the K-wire as the stability of these two constructs are comparable and portrayed no significant difference when compared to that of the center crossing point. Additionally, it is essential to avoid the medial crossing point as it is significantly less stable in terms of rotational force when compared to the center crossing point.
Objective To compare long-term functional results of ACL reconstruction with a single bundle (SB) and double bundle (DB). Methods Sixty patients who underwent ACL reconstructions from January 2007 to December 2008 were retrospectively evaluated (30 SB and 30 DB ACL reconstructions). Clinical and functional outcomes were measured pre- and postoperatively in terms of anterior drawer test, Lachman's test, pivot shift test, KT1000 side-to-side difference, range of motion, International Knee Documentation Committee Scoring, Lysholm knee scoring scale (LKS), and Tegner activity level scale. The period of follow-up was 10 years. Results Clinical outcome measured showed that anterior drawer test result were equally normal for both groups (93.3%; p > 0.995); however, the Lachman test was 76.7% in the DB group and 56.7% in the SB group (p > 0.100), the pivot shift was 83% in the DB group and 50% in the SB group (p < 0.001), and KT1000 was 76.7% in the DB group and 56.7% in the SB group (p > 0.100). Regarding the functional outcome, it favored the DB group of patients, with the LKS being statistically significant (p < 0.007) and the Tegner activity level scale p-value being <0.001 Conclusions DB ACL reconstruction produces better rotational stability and gives superior functional outcome in terms of return to pre-injury activity level in comparison to SB reconstruction. DB ACL reconstruction using hamstring tendon autograft produces better functional results at 10 years follow-up.
Dorsal dislocations of proximal interphalangeal joint with palmar lip fractures base of middle phalanx of fingers are rare, complex, and often a challenging injury to the treating hand surgeons especially in those chronic cases. Hemi-hamate arthroplasty is the preferred surgical option in treating chronic dorsal fracture-dislocations of the proximal interphalangeal joint. We report two cases with a chronic injury that have been treated with hemi-hamate arthroplasty. Range of motion, pinch and grip strengths, QuickDASH scores, complications, and radiological findings were recorded at follow-up. Good functional outcomes were observed in both patients without major complications. Hemi-hamate arthroplasty can be a reliable surgical treatment for chronic proximal interphalangeal joint fracture-dislocations.
Amodal (redundant) and arbitrary cross-sensory feature associations involve the context-insensitive mapping of absolute feature values across sensory domains. Cross-sensory associations of a different kind, known as correspondences, involve the context-sensitive mapping of relative feature values. Are such correspondences in place at birth (like amodal associations), or are they learned from subsequently experiencing relevant feature co-occurrences in the world (like arbitrary associations)? To decide between these two possibilities, human newborns (median age = 44 hr) watched animations in which two balls alternately rose and fell together in space. The pitch of an accompanying sound rose and fell either congruently with this visual change (pitch rising and falling as the balls moved up and down), or incongruently (pitch rising and falling as the balls moved down and up). Newborns' looking behavior was sensitive to this congruence, providing the strongest indication to date that cross-sensory correspondences can be in place at birth.
This study examined the kinematic differences between a body-powered prosthesis and a biomechatronics prosthesis as a transradial amputee performed activities that involve flexion/extension and supination/pronation of the wrist.
Matched MeSH terms: Range of Motion, Articular/physiology*
The high risk of knee injuries in female may be associated with sex-steroid hormone fluctuations during the menstrual cycle by its effect on ligaments and tendons stiffness. This study examined changes in knee range of motion in presence of estrogen and progesterone and investigated the interaction of their antagonists to relaxin receptors.
Matched MeSH terms: Range of Motion, Articular/drug effects*
This study investigated effects of wearing compression garments and textured insoles on modes of movement organisation emerging during performance of lower limb interceptive actions in association football. Participants were six skilled (age = 15.67 ± 0.74 years) and six less-skilled (age = 15.17 ± 1.1 years) football players. All participants performed 20 instep kicks with maximum velocity in four randomly organised insoles and socks conditions, (a) Smooth Socks with Smooth Insoles (SSSI); (b) Smooth Socks with Textured Insoles (SSTI); (c) Compression Socks with Smooth Insoles (CSSI); and (d), Compression Socks with Textured Insoles (CSTI). Results showed that, when wearing textured and compression materials (CSSI condition), less-skilled participants displayed significantly greater hip extension and flexion towards the ball contact phase, indicating larger ranges of motion in the kicking limb than in other conditions. Less-skilled participants also demonstrated greater variability in knee-ankle intralimb (angle-angle plots) coordination modes in the CSTI condition. Findings suggested that use of textured and compression materials increased attunement to somatosensory information from lower limb movement, to regulate performance of dynamic interceptive actions like kicking, especially in less-skilled individuals.
Matched MeSH terms: Range of Motion, Articular/physiology
This study aimed to objectively evaluate changes in gait kinematics, kinetics and symmetry among anterior cruciate ligament (ACL) reconstructed athletes during rehabilitation. Twenty-two national athletes with ACL reconstruction and 15 healthy athletes were recruited for the study. Gait data were collected between the weeks 4-5, 8-9, and 12-13 post-operation using three-dimensional motion analysis system. Five separate components, including knee range of motion (ROM), vertical ground reaction force (VGRF), their symmetries and knee extension moment were evaluated. One way and repeated measure multivariate analysis of variance (MANOVA) were used to analyze the knee ROMs. The VGRF and extension moment were tested using repeated measure ANOVA and independent sample t-test. Findings indicated significant alterations in all measured components between patients' Test 1 and control group. Repeated measure analysis revealed significant effect for time in components of knee angular and VGRF (P<0.001), their symmetry index (P=0.03) and knee extension moment (P=0.045). Univariate outcomes demonstrated significant improvement in the injured limb's stance and swing (P<0.001), and single-stance (P=0.005) ROMs over time. Symmetry indexes of stance and swing ROM, and VGRF reduced significantly by 26.3% (P=0.001), 17.9% (P<0.001), and 31.9% (P=0.03) respectively. After three months, symmetry indexes of single-stance ROM and VGRF along with operated knee extension moment were the only variables which showed significant differences with control group. The rehabilitation program allowed national athletes to restore the operated limb's gait parameters except knee extension moment by 12-13 weeks post-reconstruction; however, more time is required to normalize single-stance ROM and VGRF asymmetries.
The synovial fluid motion in an artificial hip joint is important in understanding the thermo-fluids effects that can affect the reliability of the joint, although it is difficult to be studied theoretically, as the modelling involves the viscous fluid interacting with a moving surface. A new analytical solution has been derived for the maximum induced fluid motion within a spherical gap with an oscillating lower surface and a stationary upper surface, assuming one-dimensional incompressible laminar Newtonian flow with constant properties, and using the Navier-Stokes equation. The resulting time-dependent motion is analysed in terms of two dimensionless parameters R and β, which are functions of geometry, fluid properties and the oscillation rate. The model is then applied to the conditions of the synovial fluid enclosed in the artificial hip joint and it is found that the motion may be described by a simpler velocity variation, whereby laying the foundation to thermal studies in the joint.
This study investigates the numerical solutions of MHD boundary layer and heat transfer of the Williamson fluid flow on the exponentially vertical shrinking sheet, having variable thickness and thermal conductivity under effects of the velocity and thermal slip parameters. It is also assumed that shrinking/stretching velocity, as well as the wall temperature, has the exponential function form. In this study, the continuity, momentum and energy equations with buoyancy parameter and Hartmann number are incorporated especially in the Williamson fluid flow case. Similarity transformation variables have been employed to formulate the ordinary differential equations (ODEs) from partial differential equations (PDEs). The resultant ODEs are solved by shooting method with Runge Kutta of fourth order method in Maple software. The effects of the different applied non-dimensional physical parameters on the boundary layer and heat transfer flow problems are presented in graphs. The effects of Williamson parameter, Prandtl number, and slip parameters on velocity and temperature profiles have been thoroughly demonstrated and discussed. The numerical results show that the buoyancy force and the slip parameters contribute to the occurrence of the dual solutions on the boundary layer and heat transfer flow problems. Furthermore, the stability analysis suggests that the first solution is stable and physically possible.
Introduction: Hamstring tendon (HT) and bone patellar tendon bone (BPTB) are the commonly used
autograft in an anterior cruciate ligament reconstruction surgery. The BPTB is said to have more incidence of
anterior knee pain compared to HT. The study aimed to compare the severity of knee pain during Islamic
prayer kneeling. Methods: A cross sectional cohort analysis of patients undergoing ACL reconstruction surgery
using BPTB with HT autografts was conducted to determine differences in postoperative pain while kneeling
and ability to pray in normal position. Kneeling during prayer and the ability to sit while performing prayer
were assessed at 3rd, 4th, 5th and 6th month. Results: There were no significant differences in mean pain score
while kneeling at 3rd, 4th, 5th and 6th month. The mean difference of patient’s ability to perform normal
prayers for BPTB (3.56+1.16) and HT (3.30+1.05) was found insignificant. The average number of patients in
both groups was able to pray between 3 to 4 months post operatively as full range of motion of knee is
allowed within this period. Total 49 patients (BPTB 23, HT 26) out of 60 were able to pray normally within 4
months post-operation. Mostly delayed due to anterior knee pain. Conclusion: There is no different in term of
knee pain during kneeling while performing Islamic prayer between those who had their ACL reconstructed
either using BPTB or HT autograft.
This paper establishes a novel control strategy for a nonlinear bilateral macro-micro teleoperation system with time delay. Besides position and velocity signals, force signals are additionally utilized in the control scheme. This modification significantly improves the poor transparency during contact with the environment. To eliminate external force measurement, a force estimation algorithm is proposed for the master and slave robots. The closed loop stability of the nonlinear micro-micro teleoperation system with the proposed control scheme is investigated employing the Lyapunov theory. Consequently, the experimental results verify the efficiency of the new control scheme in free motion and during collision between the slave robot and the environment of slave robot with environment, and the efficiency of the force estimation algorithm.
The data distribution system of this project is divided into two types, which are a Two-PC Image Reconstruction System and a Two-PC Velocity Measurement System. Each data distribution system is investigated to see whether the results' refreshing rate of the corresponding measurement can be greater than the rate obtained by using a single computer in the same measurement system for each application. Each system has its own flow control protocol for controlling how data is distributed within the system in order to speed up the data processing time. This can be done if two PCs work in parallel. The challenge of this project is to define the data flow process and critical timing during data packaging, transferring and extracting in between PCs. If a single computer is used as a data processing unit, a longer time is needed to produce a measurement result. This insufficient real-time result will cause problems in a feedback control process when applying the system in industrial plants. To increase the refreshing rate of the measurement result, an investigation on a data distribution system is performed to replace the existing data processing unit.
The Round Table Cinema Activity (RTCA) is an intervention designed to promote improved multicultural understanding by having different social identity groups watch a carefully-selected film and take part in repeated dialogic exchanges. Here, we examined the efficacy of the RTCA paradigm at improving inter-ethnic understanding and empathy among members of different social identity groups from the same country (i.e., Malaysian Malays and Chinese). A total of 87 participants completed a measure of ethnocultural empathy before and after the RTCA paradigm, which involved watching the film Sepet, taking part in group discussions, and answering open-ended question about their experiences. Analyses of written responses suggested that the RTCA was successful at promoting intergroup dialogue and exchange of ideas. Analyses of quantitative data suggested significant and large improvements in ethnocultural empathy at post-intervention. Our findings suggest that the RTCA paradigm may be a useful tool for promoting inter-ethnic harmony in the Malaysian context.
Introduction: This is a cross-sectional study of 37 patients with AO type C (complete intra-articular) fractures of the distal radius, evaluating the functional, anatomical, and patient rated outcomes one year after primary fixation with a volar locking plate.
Methods: Functional outcomes were assessed based on the grip strength, and the range of motion of forearm and wrist. Anatomical outcomes were assessed based on the radial inclination, radial height, volar tilt, and articular step or gap. Patient rated outcome was measured with a Disability of arm, shoulder and hand (DASH) questionnaire.
Results: One year after surgery, 24 (64%) patients achieved good and excellent anatomical results, and DASH scores were acceptable in 73% of patients. Most of the patients had achieved 80% of their grip strength. The mean DASH score of 12.3 was comparable with other studies. Grip strength, radial inclination and volar tilt had a significant correlation with the DASH score.
Conclusion: Volar locking plates can be used to achieve optimal reduction in all three parameters in the treatment of AO type C fractures of the distal radius. Versatile fracture fragment reduction and angular stability enable rehabilitation hence obtaining good functional outcomes.
Introduction: Praying represents a fundamental activity of daily living in Muslim community. Muslims need to adopt several postures that require deep flexion of the knee and hip to perform this daily obligation. This is a preliminary report of the study on hip and knee range of motion conducted to obtain normative passive and functional range of flexion data during Muslim prayers in both weight-bearing joints of normal Muslim adults. Methods: A cohort of Malay men aged between 20 to 30 years was recruited in this cross-sectional study. Passive range of motion and flexion angles of the joints in various postures during prayer were measured using a standard goniometer. The difference against existing normative range of motion database available and the influence of various factors were analysed. Factors analysed include body mass index and other anthropometric measurements. Results: Sixty participants recruited for the preliminary phase of this study. The mean (SD) of passive hip and knee flexions were higher compared to other existing normative range of motion database. A unit increase in body mass index will have 0.782 units lower of knee range of motion. The hip and knee flexion arc were from 74.1° to 119.0° and from 3.3° to 119.7° respectively. Conclusion: The range of motion involved for prayers was more for the knee but less for the hip as compared to the measured passive range of motion. Body mass index has a significant linear negative relationship with the passive range of motion of the knee, but not the hip.
Transformed domain sparsity of Magnetic Resonance Imaging (MRI) has recently been used to reduce the acquisition time in conjunction with compressed sensing (CS) theory. Respiratory motion during MR scan results in strong blurring and ghosting artifacts in recovered MR images. To improve the quality of the recovered images, motion needs to be estimated and corrected. In this article, a two-step approach is proposed for the recovery of cardiac MR images in the presence of free breathing motion. In the first step, compressively sampled MR images are recovered by solving an optimization problem using gradient descent algorithm. TheL1-norm based regularizer, used in optimization problem, is approximated by a hyperbolic tangent function. In the second step, a block matching algorithm, known as Adaptive Rood Pattern Search (ARPS), is exploited to estimate and correct respiratory motion among the recovered images. The framework is tested for free breathing simulated andin vivo2D cardiac cine MRI data. Simulation results show improved structural similarity index (SSIM), peak signal-to-noise ratio (PSNR), and mean square error (MSE) with different acceleration factors for the proposed method. Experimental results also provide a comparison betweenk-tFOCUSS with MEMC and the proposed method.