First in vivo assessment of “Outwalk”: a novel protocol for clinical gait analysis based on inertial and magnetic sensors

Abstract

A protocol named "Outwalk" was recently proposed to measure the thorax-pelvis and lower-limb kinematics during gait in free-living conditions, by means of an inertial and magnetic measurement system (IMMS). The aim of this study was to validate Outwalk on four healthy subjects when it is used in combination with a specific IMMS (Xsens Technologies, NL), against a reference protocol (CAST) and measurement system (optoelectronic system; Vicon, Oxford Metrics Group, UK). For this purpose, we developed an original approach based on three tests, which allowed to separately investigate: (1) the consequences on joint kinematics of the differences between protocols (Outwalk vs. CAST), (2) the accuracy of the hardware (Xsens vs. Vicon), and (3) the summation of protocols' differences and hardware accuracy (Outwalk + Xsens vs. CAST + Vicon). In order to assess joint-angles similarity, the coefficient of multiple correlation (CMC) was used. For test 3, the CMC showed that Outwalk + Xsens and CAST + Vicon kinematics can be interchanged, offset included, for hip, knee and ankle flexion-extension, and hip ab-adduction (CMC > 0.88). The other joint-angles can be interchanged offset excluded (CMC > 0.85). Tests 1 and 2 also showed that differences in offset between joint-angles were predominantly induced by differences in the protocols; differences in correlation by both hardware and protocols; differences in range of motion by the Xsens accuracy. Results thus support the commencement of a clinical trial of Outwalk on transtibial amputees.

Shoulder biomechanics and the success of translational research

“…However, a detailed analysis of agreement between methods and procedure applied in the different clinical centers should be carried out before initiation. This is an almost unexplored topic in motion analysis in general [2,9,14,15], and for the upper extremity specifically. The paper by Parel et al [21] gives a contribution on this regard, by assessing the agreement between two scapula-tracking systems (scapula tracker [18] and spine tracker [10]), based on two different motion analysis technologies, namely opto-eletronic and inertial and magnetic sensors [10,11].…”

Multilayer perceptron for gait type classification based on inertial sensors data

“…One of the most promising approaches is the inertial sensors technology, which is simpler in usage and comparable in accuracy with the optical systems . Inertial systems have been used in many fields of medical diagnose assistance [2], i.e. : cerebral palsy [3], [4], determining gait defects, sport medicine [5].…”

Fifty years of publishing in biomedical engineering: reflections after 7-year editorship

“…To give some insight onto the best-cited original papers, we selected the top ten from the periods 2008-2009 and 2010-2011. Out of these 20 papers, 7 are in the area of the circulation [8,9,15,20,24,25,27], 7 in the area of rehabilitation including brain computer interface [6,7,11,14,16,17,28], 2 related to sleep [19,35], 2 to tissue engineering and nanotechnology and 2 to electroporation [4,21]. Obviously the distribution of these subjects of publications are somewhat influenced by the special issues we had over this period [2,5,12,18,26,31,32].…”