95 research outputs found
3D JOINT MOMENTS IN TRANSFEMORAL AND TRANSTIBIAL AMPUTEES: WHEN IS THE "GROUND REACTION VECTOR TECHNIQUE" AN ALTERNATIVE TO INVERSE DYNAMICS?
No full textThe aim of the present study was to identify the phases of gait and the joints where the "ground reaction vector technique" (GRVT) can represent an acceptable alternative to the use of inverse dynamics (ID), when considering subjects with a lower-limb amputation. First, an analytical investigation of the ID of the three joints of the lower limb is given, distinguishing the gravitational, the inertial and the ground reaction contributions. The first two contributions require inertial parameters estimation; for this purpose, literature anthropometric data are typically used, both for the unimpaired and prosthetic limb, as accurate specific inertial parameters for the prosthetic limb are difficult to obtain from companies or require time consuming estimation. This assumption potentially leads to errors in the three-dimensional (3D) joint moment estimation. Second, the results of two case studies, a trans-femoral amputee with two different prostheses and a trans-tibial amputee, showed that the GRVT can explain the most part of the net joint moment for the ankle and the knee in the whole stance phase, and for the hip in the first part of the stance, leading to a similar clinical evaluation without any assumptions on inertial parameters
Towards a Wearable System for Complete Collection of Clamp Loads in Transfemoral Paralympic Sprinters
No full textBiomechanical analysis of paralympic amputee sprinters has implications for the design of prosthetic components and for the improvement of the athletic performance. Thus, the purpose of this study was to carry out the kinetic analysis of a unilateral transfemoral amputee sprinter running on track through measurement of reaction forces and inertial data with a wearable acquisition system. The outcomes here presented find agreement with literature findings and, on top of that, add new information that strengthen knowledge in the prosthetic field and can be used for future works
Inter-operator reliability and prediction bands of a novel protocol to measure the coordinated movements of shoulder-girdle and humerus in clinical setting
No full textA clinical motion analysis protocol was developed to measure the coordinated movements of shoulder-girdle and humerus (girdle-humeral rhythm-GD-H-R) during humerus flexion-extension (HFE) and ab-adduction (HAA), through an optoelectronic system. In particular, the protocol describes the GD-H-R with 2 angle-angle plots for each movement: girdle elevation-depression and protraction-retraction vs HFE, and vs HAA. Each of these plots is further divided in two subplots, one for the upward and one for the downward phases of the movement. By involving 11 participants and 2 operators, we measured the protocol's inter-operator reliability which ranged from very-good to excellent depending on the angle-angle plot (median values of the inter-operator coefficient of multiple correlation for the angle-angle plots higher than 0.94). We then computed the subjects' average control patterns, together with statistically meaningful prediction bands. +/-1SD confidence bands were also computed and their width ranged from +/-0.5 degrees to +/-4.6 degrees . Based on these results we could conclude that the method is robust and able to identify even limited differences in the GD-H-R
Inverse dynamics vs ground reaction force vector methods: Application on lower limb amputees
No full textProgramma di Screening HCV in Regione Lombardia: dati preliminari provenienti dalla Fondazione IRCCS Policlinico S. Matteo di Pavia
No full textMethodological factors affecting joint moments estimation in clinical gait analysis: A systematic review
No full textQuantitative gait analysis can provide a description of joint kinematics and dynamics, and it is recognized as a clinically useful tool for functional assessment, diagnosis and intervention planning. Clinically interpretable parameters are estimated from quantitative measures (i.e. ground reaction forces, skin marker trajectories, etc.) through biomechanical modelling. In particular, the estimation of joint moments during motion is grounded on several modelling assumptions: (1) body segmental and joint kinematics is derived from the trajectories of markers and by modelling the human body as a kinematic chain; (2) joint resultant (net) loads are, usually, derived from force plate measurements through a model of segmental dynamics. Therefore, both measurement errors and modelling assumptions can affect the results, to an extent that also depends on the characteristics of the motor task analysed (i.e. gait speed). Errors affecting the trajectories of joint centres, the orientation of joint functional axes, the joint angular velocities, the accuracy of inertial parameters and force measurements (concurring to the definition of the dynamic model), can weigh differently in the estimation of clinically interpretable joint moments. Numerous studies addressed all these methodological aspects separately, but a critical analysis of how these aspects may affect the clinical interpretation of joint dynamics is still missing. This article aims at filling this gap through a systematic review of the literature, conducted on Web of Science, Scopus and PubMed. The final objective is hence to provide clear take-home messages to guide laboratories in the estimation of joint moments for the clinical practice
PTA del distretto iliaco: studio clinico controllato
No full textPercutaneous transluminal angioplasty CPTA) is a
frequently applied technique in the treatment of
peripheral occlusive arterial disease (PAOD) espe-
cially when it affects large and medium caliber ves-
sels. Iliac vessels PTA is preferably associated with
arterial stenting in particular in the presence of
vascular occlusion. This study evaluates the efficacy
of PTA and stenting treatment in 75 patients with
occlusion of iliac axes. The immediate results show
over 98 of success rate, and the follow-up shows
patency of treated segments and a significant impro-
vement hi periferal symptoms. There were no major
complications in the treatment of iliac PTA and sten-
ting
Men with COVID-19 die. Women survive
No full textThe severity and mortality rate of COVID-19 differ between the sexes. Several biopsychosocial determinants may account for the better outcomes in women. The notion that sex steroid hormones account for the gender disparity is reasonable but not proven; the same is true of the role of menopause as a risk factor. A retrospective analysis of patients (=1764) hospitalized in Italy showed a higher mortality (HR 1.58, 95%CI 1.30–1.91, adjusted for age and multi-comorbidities) in males only after the age of 65 (the rate is twice as high in the 65–79-year age group and 1.5-fold higher in those aged over 80). The higher mortality of men is mostly evident among those aged over 65 years, long after the average age of menopause
Kinematic analysis techniques and their application in biomechanics
No full textMotion analysis is a fundamental instrument for the quantification of joint function during daily living activities. Several devices can be used for this purpose. An overview of some of these methods is here presented, focusing mainly on i) stereophotogrammetry (flexible and wide-spread), ii) 3D fluoroscopy (accurate but invasive), iii) inertial sensors (economic though not very accurate). The main advantages and limitations of these methods are outlined, paying particular attention to the errors which can affect the estimated kinematic variables. Finally, some applications are described in the field of error compensation, joint modeling and upper limb motion analysis
Wearable sensors for the real-time assessment of gait temporal symmetry in above-knee amputees: A validation study
No full text- …
