veículo de difusão de informações em análise de marcha, reabilitação e biomecânica, captura de movimento para produções industriais
clinical gait analysis, rehabilitation and biomechanics, industrial "motion capture" (MoCap)



Biomecânica: STA - Soft Tissue Artifact

  • A linear soft tissue artefact model for human movement analysis
  • A linear soft tissue artefact model for human movement analysis:
    Proof of concept using in vivo data
    We investigated the accuracy of a linear soft tissue artefact (STA) model in human movement analysis. Simultaneously recorded bone-mounted pin and skin marker data for the thigh and shank during walking, cutting and hopping were used to measure and model the motion of the skin marker clusters within anatomical reference frames (ARFs).
  • Analysis of skeletal motion kinematics for a knee movement cycle
  • This study estimated the skeletal motion for a knee motion cycle. The surface markers on the thigh and the shank showed the computed displacement during in vivo motion analysis. This error was minimized using optimization procedure. The displacement was generally greater on the thigh than the shank. The minimization of error produced by this procedure was more successful on the thigh than the shank. The purpose of his study was to require high value motion data. These results provide the basis to calculate the instantaneous knee axis of rotation in a follow up study.
  • Can hip and knee kinematics be improved by eliminating thigh markers?
  • This study presents a comparison of hip and knee kinematics as calculated by five concurrently worn tracking marker sets during eight different tasks. The first three marker sets were based on Helen Hayes but used (1) proximal thigh wands, (2) distal thigh wands, and (3) patellar markers instead of thigh wands. The remaining two marker sets used rigid clusters on the (4) thighs and shanks and (5) only shanks. Pelvis and foot segments were shared by all marker sets.
  • Comparison of surface mounted markers
  • Comparison of surface mounted markers and atachment methods in estimating tibial rotations during walking: an in vivo study
  • Continuous Capture of Skin Deformation
  • We describe a method for the acquisition of deformable human geometry from silhouettes. Our technique uses a commercial tracking system to determine the motion of the skeleton, then estimates geometry for each bone using constraints provided by the silhouettes from one or more cameras.
  • In Vivo Knee Kinematics during Gait
  • In Vivo Knee Kinematics during Gait Reveals New Rotation Profiles and Smaller Translations
    In order to identify abnormal or pathological motions associated with clinically relevant questions such as injury mechanisms or factors leading to joint degeneration, it is essential to determine the range of normal tibiofemoral motion of the healthy knee. In this study we measured in vivo 3D tibiofemoral motion of the knee during gait and characterized the nonsagittal plane rotations and translations in a group of six healthy young adults.
  • Influence of thigh cluster configuration on the estimation of hip axial rotation
  • The non-invasive estimation of hip axial rotation is prone to error. Most of this is likely to originate from soft tissue artefact (STA) at the thigh. The purpose of this study was to evaluate the relative performance of four different thigh cluster configurations. Three were novel configurations whilst one represented the Helen Hayes convention.
  • Knee moment profiles during walking
  • Knee moment profiles during walking: errors due to soft tissue movement of the shank and the influence of the reference coordinate system
  • Non-invasive assessment of soft-tissue artifact
  • Non-invasive assessment of soft-tissue artifact and its effect on knee joint kinematics during functional activity
    The soft-tissue interface between skin-mounted markers and the underlying bones poses a major limitation to accurate, non-invasive measurement of joint kinematics. The aim of this study was twofold: first, to quantify lower limb soft-tissue artifact in young healthy subjects during functional activity; and second, to determine the effect of soft-tissue artifact on the calculation of knee joint kinematics.
  • On the influence of soft tissue coverage
  • On the influence of soft tissue coverage in the determination of bone kinematics using skin markers
    Accurate measurement of underlying bone positions is important for the understanding of normal movement and function, as well as for addressing clinical musculoskeletal or post-injury problems. Non-invasive measurement techniques are limited by the analysis technique and movement of peripheral soft tissues that can introduce significant measurement errors in reproducing the kinematics of the underlying bones when using external skin markers. Reflective markers, skeletally mounted to the right hind limb of three Merino-mix sheep were measured simultaneously with markers attached to the skin of each segment, during repetitions of gait trials. The movement of the skin markers relative to the underlying bone positions was then assessed using the Point Cluster Technique (PCT), raw averaging and the Optimal Common Shape Technique (OCST), a new approach presented in this manuscript.
  • Quantification of soft tissue artifact in lower limb human motion analysis: A systematic review
  • This systematic review critically evaluates the quantification of soft tissue artifact (STA) in lower limb human motion analysis. It has a specific focus on assessing the quality of previous studies and comparing quantitative results.
  • Soft tissue artifact assessment and compensation
  • Human movement analysis using stereophotogrammetry
    Part 3. Soft tissue artifact assessment and compensation
  • Strategy for minimising soft tissue artefact at the tibia
  • The aim of this study is to identify a subset of markers on the tibia showing the least amount of movement with respect to each other.
  • Tibiofemoral and tibiocalcaneal motion during walking
  • Tibiofemoral and tibiocalcaneal motion during walking: external vs. skeletal markers
  • Towards a marker-less human gait analysis system
  • A non–invasive system is described which is capable of extracting and describing the three–dimensional nature of human gait thereby extending the use of gait as a biometric.

Skin Deformation Measurements:

  • Capturing and Animating Skin Deformation in Human Motion
  • During dynamic activities, the surface of the human body moves in many subtle but visually significant ways: bending, bulging, jiggling, and stretching. We present a technique for capturing and animating those motions using a commercial motion capture system and approximately 350 markers.
  • Continuous Capture of Skin Deformation
  • We describe a method for the acquisition of deformable human geometry from silhouettes. Our technique uses a commercial tracking system to determine the motion of the skeleton, then estimates geometry for each bone using constraints provided by the silhouettes from one or more cameras.
  • Estimating joint kinematics from skin motion observation: modelling and validation
  • Modelling of soft tissue motion is required in many areas, such as computer animation, surgical simulation, 3D motion analysis and gait analysis. In this paper, we will focus on the use of modelling of skin deformation during 3D motion analysis.
  • Influence of soft tissue artifacts
  • Influence of soft tissue artifacts on the calculated kinematics and kinetics of total knee replacements during sit-to-stand
    The current study aimed to quantify the soft tissue artifacts of selected markers on the thigh and shank, and their effects on the calculated joint center translations, angles and moments of the knee during sitto-stand. Ten patients with total knee replacements rose from a chair under simultaneous surveillance of a motion capture system, a force-plate and a fluoroscopy system.
  • Quantification of soft tissue artefact in motion analysis
  • Quantification of soft tissue artefact in motion analysis by combining 3D fluoroscopy and stereophotogrammetry: a study on two subjects
    Two subjects, treated by total knee replacement, underwent data acquisition simultaneously with fluoroscopy and stereophotogrammetry during stair climbing, step up/down, sit-to-stand/stand-to-sit, and extension against gravity. The reference 3D kinematics of the femur and tibia was reconstructed from fluoroscopy-based tracking of the relevant prosthesis components. Soft tissue artefact was quantified as the motion of a grid of retro-reflecting makers attached to the thigh and shank with respect to the underlying bones, tracked by optoelectronic stereophotogrammetry. The propagation of soft tissue artefact to knee rotations was also calculated.
  • Soft tissue motion measurement
  • Soft tissue motion measurement on shank and thigh with MRI
  • Visualization of Local Movements for optimal Marker Positioning
  • In this paper we exploit a local fitting tool to visualize the influence of skin deformation on marker movements. Such a knowledge can in turn improve the layout of optical markers. We illustrate our viewpoint on motions of the upper-torso.

Patella Marker:

Pelve - Pelvis:

  • Alternative modelling procedures for pelvic marker occlusion
  • Motion analysis of participants with different body shapes under diverse conditions can be problematic when vitalmarkers are occluded. The markers located over the anterior superior iliac spines are commonly occluded in older patients and during analysis of activities with trunk and hip flexion which can prevent accurate calculation of lower limb joint kinematics. Options to modify standard body models exist but have not been described in detail, and the effects on the lower limb kinematics are not known.
  • Evaluation of alternative technical markers for the pelvic coordinate system
  • In this study, we evaluated alternative technical markers for the motion analysis of the pelvic segment.