3,161 research outputs found
Does inter-vertebral range of motion increase after spinal manipulation? A prospective cohort study.
Background: Spinal manipulation for nonspecific neck pain is thought to work in part by improving inter-vertebral range of motion (IV-RoM), but it is difficult to measure this or determine whether it is related to clinical outcomes.
Objectives: This study undertook to determine whether cervical spine flexion and extension IV-RoM increases after a course of spinal manipulation, to explore relationships between any IV-RoM increases and clinical outcomes and to compare palpation with objective measurement in the detection of hypo-mobile segments.
Method: Thirty patients with nonspecific neck pain and 30 healthy controls matched for age and gender received quantitative fluoroscopy (QF) screenings to measure flexion and extension IV-RoM (C1-C6) at baseline and 4-week follow-up between September 2012-13. Patients received up to 12 neck manipulations and completed NRS, NDI
and Euroqol 5D-5L at baseline, plus PGIC and satisfaction questionnaires at follow-up. IV-RoM accuracy, repeatability and hypo-mobility cut-offs were determined. Minimal detectable changes (MDC) over 4 weeks were calculated
from controls. Patients and control IV-RoMs were compared at baseline as well as changes in patients over 4 weeks. Correlations between outcomes and the number of manipulations received and the agreement (Kappa) between palpated and QF-detected of hypo-mobile segments were calculated.
Results: QF had high accuracy (worst RMS error 0.5o) and repeatability (highest SEM 1.1o, lowest ICC 0.90) for
IV-RoM measurement. Hypo-mobility cut offs ranged from 0.8o to 3.5o. No outcome was significantly correlated with increased IV-RoM above MDC and there was no significant difference between the number of hypo-mobile segments in patients and controls at baseline or significant increases in IV-RoMs in patients. However, there was a modest and significant correlation between the number of manipulations received and the number of levels and directions whose IV-RoM increased beyond MDC (Rho=0.39, p=0.043). There was also no agreement between palpation and QF in identifying hypo-mobile segments (Kappa 0.04-0.06).
Conclusions: This study found no differences in cervical sagittal IV-RoM between patients with non-specific neck pain and matched controls. There was a modest dose-response relationship between the number of manipulations given and number of levels increasing IV-RoM - providing evidence that neck manipulation has a mechanical effect at segmental levels. However, patient-reported outcomes were not related to this
A surgical system for automatic registration, stiffness mapping and dynamic image overlay
In this paper we develop a surgical system using the da Vinci research kit
(dVRK) that is capable of autonomously searching for tumors and dynamically
displaying the tumor location using augmented reality. Such a system has the
potential to quickly reveal the location and shape of tumors and visually
overlay that information to reduce the cognitive overload of the surgeon. We
believe that our approach is one of the first to incorporate state-of-the-art
methods in registration, force sensing and tumor localization into a unified
surgical system. First, the preoperative model is registered to the
intra-operative scene using a Bingham distribution-based filtering approach. An
active level set estimation is then used to find the location and the shape of
the tumors. We use a recently developed miniature force sensor to perform the
palpation. The estimated stiffness map is then dynamically overlaid onto the
registered preoperative model of the organ. We demonstrate the efficacy of our
system by performing experiments on phantom prostate models with embedded stiff
inclusions.Comment: International Symposium on Medical Robotics (ISMR 2018
Real-Time Evaluation of Breast Self-Examination Using Computer Vision
Breast cancer is the most common cancer among women worldwide and breast self-examination (BSE) is considered as the most
cost-effective approach for early breast cancer detection. The general objective of this paper is to design and develop a computer
vision algorithm to evaluate the BSE performance in real-time. The first stage of the algorithm presents a method for detecting and
tracking the nipples in frames while a woman performs BSE; the second stage presents amethod for localizing the breast region and
blocks of pixels related to palpation of the breast, and the third stage focuses on detecting the palpated blocks in the breast region.
The palpated blocks are highlighted at the time of BSE performance. In a correct BSE performance, all blocks must be palpated,
checked, and highlighted, respectively. If any abnormality, such as masses, is detected, then this must be reported to a doctor to
confirm the presence of this abnormality and proceed to perform other confirmatory tests. The experimental results have shown
that the BSE evaluation algorithm presented in this paper provides robust performance
Real-Time Evaluation of Breast Self-Examination Using Computer Vision
Breast cancer is the most common cancer among women worldwide and breast self-examination (BSE) is considered as the most
cost-effective approach for early breast cancer detection. The general objective of this paper is to design and develop a computer
vision algorithm to evaluate the BSE performance in real-time. The first stage of the algorithm presents a method for detecting and
tracking the nipples in frames while a woman performs BSE; the second stage presents amethod for localizing the breast region and
blocks of pixels related to palpation of the breast, and the third stage focuses on detecting the palpated blocks in the breast region.
The palpated blocks are highlighted at the time of BSE performance. In a correct BSE performance, all blocks must be palpated,
checked, and highlighted, respectively. If any abnormality, such as masses, is detected, then this must be reported to a doctor to
confirm the presence of this abnormality and proceed to perform other confirmatory tests. The experimental results have shown
that the BSE evaluation algorithm presented in this paper provides robust performance
A Framework for Tumor Localization in Robot-Assisted Minimally Invasive Surgery
Manual palpation of tissue is frequently used in open surgery, e.g., for localization of tumors and buried vessels and for tissue characterization. The overall objective of this work is to explore how tissue palpation can be performed in Robot-Assisted Minimally Invasive Surgery (RAMIS) using laparoscopic instruments conventionally used in RAMIS. This thesis presents a framework where a surgical tool is moved teleoperatively in a manner analogous to the repetitive pressing motion of a finger during manual palpation. We interpret the changes in parameters due to this motion such as the applied force and the resulting indentation depth to accurately determine the variation in tissue stiffness. This approach requires the sensorization of the laparoscopic tool for force sensing. In our work, we have used a da Vinci needle driver which has been sensorized in our lab at CSTAR for force sensing using Fiber Bragg Grating (FBG). A computer vision algorithm has been developed for 3D surgical tool-tip tracking using the da Vinci \u27s stereo endoscope. This enables us to measure changes in surface indentation resulting from pressing the needle driver on the tissue. The proposed palpation framework is based on the hypothesis that the indentation depth is inversely proportional to the tissue stiffness when a constant pressing force is applied. This was validated in a telemanipulated setup using the da Vinci surgical system with a phantom in which artificial tumors were embedded to represent areas of different stiffnesses. The region with high stiffness representing tumor and region with low stiffness representing healthy tissue showed an average indentation depth change of 5.19 mm and 10.09 mm respectively while maintaining a maximum force of 8N during robot-assisted palpation. These indentation depth variations were then distinguished using the k-means clustering algorithm to classify groups of low and high stiffnesses. The results were presented in a colour-coded map. The unique feature of this framework is its use of a conventional laparoscopic tool and minimal re-design of the existing da Vinci surgical setup. Additional work includes a vision-based algorithm for tracking the motion of the tissue surface such as that of the lung resulting from respiratory and cardiac motion. The extracted motion information was analyzed to characterize the lung tissue stiffness based on the lateral strain variations as the surface inflates and deflates
Contactless Remote Induction of Shear Waves in Soft Tissues Using a Transcranial Magnetic Stimulation Device
This study presents the first observation of shear wave induced remotely
within soft tissues. It was performed through the combination of a transcranial
magnetic stimulation device and a permanent magnet. A physical model based on
Maxwell and Navier equations was developed. Experiments were performed on a
cryogel phantom and a chicken breast sample. Using an ultrafast ultrasound
scanner, shear waves of respective amplitude of 5 and 0.5 micrometers were
observed. Experimental and numerical results were in good agreement. This study
constitutes the framework of an alternative shear wave elastography method
Validity and reliability of 3D marker based scapular motion analysis : a systematic review
Methods based on cutaneous markers are the most popular for the recording of three dimensional scapular motion analysis. Numerous methods have been evaluated, each showing different levels of accuracy and reliability. The aim of this review was to report the metrological properties of 3D scapular kinematic measurements using cutaneous markers and to make recommendations based on metrological evidence.
A database search was conducted using relevant keywords and inclusion/exclusion criteria in 5 databases. 19 articles were included and assessed using a quality score. Concurrent validity and reliability were analyzed for each method.
Six different methods are reported in the literature, each based on different marker locations and post collection computations. The acromion marker cluster (AMC) method coupled with a calibration of the scapula with the arm at rest is the most studied method. Below 90–100° of humeral elevation, this method is accurate to about 5° during arm flexion and 7° during arm abduction compared to palpation (average of the 3 scapular rotation errors). Good to excellent within-session reliability and moderate to excellent between-session reliability have been reported. The AMC method can be improved using different or multiple calibrations. Other methods using different marker locations or more markers on the scapula blade have been described but are less accurate than AMC methods.
Based on current metrological evidence we would recommend (1) the use of an AMC located at the junction of the scapular spine and the acromion, (2) the use of a single calibration at rest if the task does not reach 90° of humeral elevation, (3) the use of a second calibration (at 90° or 120° of humeral elevation), or multiple calibrations above 90° of humeral elevation
Tracking scapular movement
Measuring the three-dimensional movement of the scapula provides vital information in
the analysis and treatment of shoulder clinical disorders and contributes to our
understanding of its complex kinematics. However, the thick layer of skin overlying the
scapular region means that all skin-based techniques inaccurately determine the scapular
kinematics. The scapula locator makes use of a palpation technique in order to reduce the
problem of skin deformation. At present, the scapula locator is the most accurate noninvasive
method of measuring scapular movements, but to date the method has only been
used to measure the scapula position statically.
Here, a new method was developed to measure the scapula movements dynamically; the
method makes use of the scapula locator and feedback from pressure-sensors attached to
the locator probes to track the scapula during movement. The reliability of the method
after short-term practise as well as the intra-observer and inter-observer variations and the
inter-session repeatability were tested and quantified in a series of studies.
The method was found to be able to measure dynamic scapular movements in slow to
medium paced arm movements to a good degree of accuracy as well as provide
scapulothoracic measurements of high reliability compared to using the scapula locator
on its own and to previously reported results in the literature.
Finally, the new locator method was used to calibrate the acromial tracker in order to
improve the accuracy of the device and facilitate its use as an alternative to the scapula
locator in clinical studies involving fast (higher than functional velocities) dynamic
activities.
The new scapula locator method and the calibrated acromial tracker method present
significant improvements on the available scapular measurement techniques particularly
in measuring subtle scapular rotations of clinical importance, such as the scapular tilt. The
methods described will be used in future clinical and sport-related studies
Posture flexibility and grip strength in horse riders
Since the ability to train the horse to be ambidextrous is considered highly desirable, rider asymmetry is recognized as a negative trait. Acquired postural and functional asymmetry can originate from numerous anatomical regions, so it is difficult to suggest if any is developed due to riding. The aim of this study was therefore to assess symmetry of posture, strength and flexibility in a large population of riders and to determine whether typical traits exist due to riding. 127 right handed riders from the UK and USA were categorized according to years riding (in 20 year increments) and their competition level (using affiliated test levels). Leg length, grip strength and spinal posture were measured and recorded by a physiotherapist. Standing and sitting posture and trunk flexibility were measured with 3-D motion capture technology. Right-left differences were explored in relation to years riding and rider competitive experience. Significant anatomical asymmetry was found for the difference in standing acromion process height for a competition level (-0.07±1.50 cm Intro/Prelim; 0.02±1.31 cm Novice; 0.43±1.27 cm Elementary+; p=0.048) and for sitting iliac crest height for years riding (-0.23±1.36 cm Intro/Prelim; 0.01±1.50 cm Novice; 0.86±0.41 cm Elementary+;p=0.021). For functional asymmetry, a significant interaction was found for lateral bending ROM for years riding x competition level (p=0.047). The demands on dressage riders competing at higher levels may predispose these riders to a higher risk of developing asymmetry and potentially chronic back pain rather than improving their symmetry
Medical image computing and computer-aided medical interventions applied to soft tissues. Work in progress in urology
Until recently, Computer-Aided Medical Interventions (CAMI) and Medical
Robotics have focused on rigid and non deformable anatomical structures.
Nowadays, special attention is paid to soft tissues, raising complex issues due
to their mobility and deformation. Mini-invasive digestive surgery was probably
one of the first fields where soft tissues were handled through the development
of simulators, tracking of anatomical structures and specific assistance
robots. However, other clinical domains, for instance urology, are concerned.
Indeed, laparoscopic surgery, new tumour destruction techniques (e.g. HIFU,
radiofrequency, or cryoablation), increasingly early detection of cancer, and
use of interventional and diagnostic imaging modalities, recently opened new
challenges to the urologist and scientists involved in CAMI. This resulted in
the last five years in a very significant increase of research and developments
of computer-aided urology systems. In this paper, we propose a description of
the main problems related to computer-aided diagnostic and therapy of soft
tissues and give a survey of the different types of assistance offered to the
urologist: robotization, image fusion, surgical navigation. Both research
projects and operational industrial systems are discussed
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