Embedded System for Prosthetic Interface Mapping of Lower Limbs Amputees

Author(s):  
Maurizio Rossi ◽  
Leandro Lorenzelli ◽  
Davide Brunelli
Keyword(s):  
2020 ◽  
Vol 10 (2) ◽  
pp. 14 ◽  
Author(s):  
Francisco Luna-Perejón ◽  
Manuel Domínguez-Morales ◽  
Daniel Gutiérrez-Galán ◽  
Antón Civit-Balcells

Abnormal foot postures can be measured during the march by plantar pressures in both dynamic and static conditions. These detections may prevent possible injuries to the lower limbs like fractures, ankle sprain or plantar fasciitis. This information can be obtained by an embedded instrumented insole with pressure sensors and a low-power microcontroller. However, these sensors are placed in sparse locations inside the insole, so it is not easy to correlate manually its values with the gait type; that is why a machine learning system is needed. In this work, we analyse the feasibility of integrating a machine learning classifier inside a low-power embedded system in order to obtain information from the user’s gait in real-time and prevent future injuries. Moreover, we analyse the execution times, the power consumption and the model effectiveness. The machine learning classifier is trained using an acquired dataset of 3000+ steps from 6 different users. Results prove that this system provides an accuracy over 99% and the power consumption tests obtains a battery autonomy over 25 days.


2019 ◽  
Vol 9 (19) ◽  
pp. 3970 ◽  
Author(s):  
Manuel J. Domínguez-Morales ◽  
Francisco Luna-Perejón ◽  
Lourdes Miró-Amarante ◽  
Mariló Hernández-Velázquez ◽  
José L. Sevillano-Ramos

Abnormal foot postures during gait are common sources of pain and pathologies of the lower limbs. Measurements of foot plantar pressures in both dynamic and static conditions can detect these abnormal foot postures and prevent possible pathologies. In this work, a plantar pressure measurement system is developed to identify areas with higher or lower pressure load. This system is composed of an embedded system placed in the insole and a user application. The instrumented insole consists of a low-power microcontroller, seven pressure sensors and a low-energy bluetooth module. The user application receives and shows the insole pressure information in real-time and, finally, provides information about the foot posture. In order to identify the different pressure states and obtain the final information of the study with greater accuracy, a Deep Learning neural network system has been integrated into the user application. The neural network can be trained using a stored dataset in order to obtain the classification results in real-time. Results prove that this system provides an accuracy over 90% using a training dataset of 3000+ steps from 6 different users.


VASA ◽  
2012 ◽  
Vol 41 (2) ◽  
pp. 132-135 ◽  
Author(s):  
Krohn ◽  
Gebauer ◽  
Hübler ◽  
Beck

The mid-aortic syndrome is an uncommon clinical condition characterized by severe narrowing of the descending aorta, usually with involvement of its renal and visceral branches, presenting with uncontrollably elevated blood pressures of the upper body, renal and cardiac failure, intestinal ischemia, encephalopathy symptoms and claudication of the lower limbs, although clinical presentation is variable. In this article we report the case of an eleven-year-old patient with the initial diagnosis of a mid-aortic syndrome and present the computed tomography angiography pictures and reconstructions before and after surgical therapy.


Phlebologie ◽  
2008 ◽  
Vol 37 (05) ◽  
pp. 247-252 ◽  
Author(s):  
V. S. Brauer ◽  
W. J. Brauer

SummaryPurpose: Comparison of qualitative and quantitative sonography with the lymphoscintigraphic function test and clinical findings in legs. Patients, methods: In 33 patients a lymphoscintigraphic function test of legs combined with measurement of lymph node uptake was performed and subsequently compared with sonography. Sonographic criteria were: Thickness of cutis, thickness of subcutanean fatty tissue and presence of liquid structures or fine disperse tissue structure of lower limbs, foots and toes. Results: In 51 legs uptake values lie in the pathologic area, in four legs in the grey area and in ten legs in the normal area. The cutis thickness in the lower leg shows no significant correlation with the uptake. The determination of the thickness of the subcutanean fatty tissue of the lower leg and of the cutis thickness of the feet turned out to be an unreliable method. In 47% of the medial lower legs and in 57% of the lateral lower legs with clinical lymphoedema sonography is falsely negative. Conclusion: Early lymphoedema is only detectable with the lymphoscintigraphic function test. In the case of clinical lymphoedema clinical examination is more reliable than sonography.


1990 ◽  
Vol 29 (05) ◽  
pp. 215-220 ◽  
Author(s):  
R. Benning ◽  
K. Nagel ◽  
M. Jugenheimer ◽  
S. Fischer ◽  
S. Worthmann ◽  
...  

A new 99mTc-labelled tracer (99mTc-Sestanriibi) was used for the first time to demonstrate the perfusion of the skeletal muscle. In 16 patients with obstructive atherosclerosis of the lower limbs the change of perfusion of thigh and lower leg was studied with SPECT before and after vascular surgery (n = 11) or percutaneous transluminal angioplasty (n = 5). Comparative results of scintigraphic measurements and clinical observations (ancle-arm pressure, treadmill test) in 10 surgical patients (14 operated legs) showed correct positive or negative results in 86% (12/14).


1990 ◽  
Vol 63 (01) ◽  
pp. 076-081 ◽  
Author(s):  
Pascale Gaussem ◽  
Sophie Gandrille ◽  
Pascale Molho-Sabatier ◽  
Loïc Capron ◽  
Jean-Noël Fiessinger ◽  
...  

SummaryUsing a monoclonal antibody-based assay, we measured the fibrin degradation product release in the supernatant of plasma clots obtained before and after venous occlusion (VO) in 30 patients with definite or suspected vascular thrombosis (19 definite and 2 suspected deep vein thrombosis, 6 recurrent superficial thrombophlebitis, 3 arterial occlusions of lower limbs). tPA and PAI-1 concentrations were determined using ELISA assays; the post-occlusion values were corrected for haemoconcentration. The increase in tPA during VO was correlated with haemoconcentration (r = 0.74), but 3 patients had ineffective VO (<2% increase in proteins). The fibrinolytic response to VO was evaluated using the shortening of the time necessary for the release of 200 μg of fibrin degradation products per mg of fibrinogen (Δ T 200). Two among the 27 patients with effective VO were bad responders with a Δ T 200 <3 h (whereas all the others had Δ T 200 >10 h). These patients had respectively a deficient tPA release (Δ tPA = 1 ng/ml) and an elevated PAI-1 level at rest (33 ng/ml). Several other patients were bad responders in terms of tPA release or of shortening of the euglobulin clot lysis time but they had a normal Δ T 200. This plasma clot test reflects the ability of free tPA to bind to fibrin (the amount of which depends on the level of tPA and PAI-1), and may be useful in the diagnosis of a hypofibrinolytic state.


1996 ◽  
Vol 76 (04) ◽  
pp. 518-522 ◽  
Author(s):  
A Elias ◽  
I Aptel ◽  
B Huc ◽  
J J Chale ◽  
F Nguyen ◽  
...  

SummaryThe current D-Dimer ELISA methods provide high sensitivity and negative predictive value for the diagnosis of deep vein thrombosis but these methods are not suitable for emergency or for individual determination. We have evaluated the performance of 3 newly available fast D-Dimer assays (Vidas D-Di, BioMerieux; Instant IA D-Di, Stago; Nycocard D-Dimer, Nycomed) in comparison with 3 classic ELISA methods (Stago, Organon, Behring) and a Latex agglutination technique (Stago). One-hundred-and-seventy-one patients suspected of presenting a first episode of deep vein thrombosis were investigated. A deep vein thrombosis was detected in 75 patients (43.8%) by ultrasonic duplex scanning of the lower limbs; in 11 of them the thrombi were distal and very limited in size (<2 cm). We compared the performance of the tests by calculating their sensitivity, specificity, positive and negative predictive value for different cut-off levels and by calculating the area under ROC curves. The concordance of the different methods was evaluated by calculating the kappa coefficient. The performances of the 3 classic ELISA and of the Vidas D-Di were comparable and kappa coefficients indicated a good concordance between the results provided by these assays. Their sensitivity slightly declined for detection of the very small thrombi. Instant IA D-Di had a non-significantly lower sensitivity and negative predictive value than the 4 previous assays; however its performance was excellent for out-patients. As expected, the Latex assay had too low a sensitivity and negative predictive value to be recommended. In our hands, Nycocard D-Dimer also exhibited low sensitivity and negative predictive value, which were significantly improved when the plasma samples were tested by the manufacturer. Thus significant progress has been made, allowing clinical studies to be planned to compare the safety and cost-effectiveness of D-Dimer strategy to those of the conventional methods for the diagnosis of venous thrombosis.


1980 ◽  
Vol 44 (03) ◽  
pp. 167-167 ◽  
Author(s):  
B Boneu ◽  
P Sie ◽  
C Caranobe ◽  
D Lefebvre ◽  
B Pradere ◽  
...  
Keyword(s):  

1982 ◽  
Vol 47 (02) ◽  
pp. 141-144 ◽  
Author(s):  
H Bounameaux ◽  
B Krähenbühl ◽  
S Vukanovic

SummaryDoppler ultrasound flow examination, strain gauge plethysmography and contrast venography were performed in 160 lower limbs of 80 in-patients. Deep vein thrombosis (DVT) was suspected in 87 limbs. Using measurement of venous stop-flow pressure, the Doppler method had an overall sensitivity of 83%. By combined use of Doppler and Plethysmography, sensitivity was increased to 96%. Specificity was 62% and 51%, respectively. With a positive and a negative predictive value of 80% and 73%, respectively, the combination of both non-invasive methods cannot reliably replace venography in the diagnosis of DTV, although all (40/40) thromboses proximal to or involving the popliteal segment were detected by either Doppler and Plethysmography or both.After exclusion of 14 patients (18%) suffering from conditions known to alter the results of these non-invasive methods, the positive predictive value of abnormal findings in both Doppler and Plethysmography was increased to 94% for suspected limbs, whilst negative predictive value of both negative Doppler and Plethysmography was 90%, allowing the avoidance of venography in these patients.


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