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The relationship between cognitive function and breath-holding time is in need of further investigation. We aim to determine whether cognitive mobile games (CMG) are sensitive enough to assess the link between cognition and breath-holding time in non-trained subjects. Thirty-one healthy subjects participated in this study. A set of 3 short CMG: Must Sort (response control), Rush Back (attention, working memory) and True Color (mental flexibility, inhibition) was used. Apneic time was recorded in three different conditions: Total Lung Capacity (TLC): 88 ± 35 s, Functional Residual Capacity (FRC): 49 ± 17 s, and Residual Volume (RV): 32 ± 14 s. In males, breath-holding time at RV was correlated with True Color (r = 0.48) and Rush Back (r = 0.65) and at TLC with True Color (r = 0.45). In women, breath-holding time at TLC and FRC was inversely correlated with Must Sort (r = -0.59 and r = -0.49 respectively). Males and females appeared to differ in their use of cognitive resources during different breath-holding conditions., Competing Interests: Declaration of Competing Interest None of the authors declare competing financial interests., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This paper aims at contributing to the understanding of the combination of in vivo sternum displacement, sternal angle variations and sternocostal joints (SCJ) kinematics of the seven first rib pairs over the inspiratory capacity (IC). Retrospective codified spiral-CT data obtained at total lung capacity (TLC), middle of inspiratory capacity (MIC) and at functional residual capacity (FRC) were used to compute kinematic parameters of the bones and joints of interest in a sample of 12 asymptomatic subjects. 3D models of rib, thoracic vertebra, manubrium and sternum were processed to determine anatomical landmarks (ALs) on each bone. These ALs were used to create local coordinate system and compute spatial transformation of ribs and manubrium relative to sternum, and sternum relative to thoracic vertebra. The rib angular displacements and associated orientation of rotation axes and joint pivot points (JPP), the sternal angle variations and the associated displacement of the sternum relative to vertebra were computed between each breathing pose at the three lung volumes. Results can be summarized as following: (1) sternum cephalic displacement ranged between 17.8 and 19.2mm over the IC; (2) the sternal angle showed a mean variation of 4.4°±2.7° over the IC; (3) ranges of rib rotation relative to sternum decreased gradually with increasing rib level; (4) axes of rotation were similarly oriented at each SCJ; (5) JPP spatial displacements showed less variations at first SCJ compared to levels underneath; (6) linear relation was demonstrated between SCJ ROMs and sternum cephalic displacement over the IC., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

This study investigates the relationship between the motion of the first ten costovertebral joints (CVJ) and lung volume over the inspiratory capacity (IC) using detailed kinematic analysis in a sample of 12 asymptomatic subjects. Retrospective codified spiral-CT data obtained at total lung capacity (TLC), middle of inspiratory capacity (MIC) and at functional residual capacity (FRC) were analysed. CVJ 3D kinematics were processed using previously-published methods. We tested the influence of the side, CVJ level and lung volume on CVJ kinematics. In addition, the correlations between anthropologic/pulmonary variables and CVJ kinematics were analysed. No linear correlation was found between lung volumes and CVJ kinematics. Major findings concerning 3D kinematics can be summarized as follows: 1) Ranges-of-motion decrease gradually with increasing CVJ level; 2) rib displacements are significantly reduced at lung volumes above the MIC and do not differ between CVJ levels; 3) the axes of rotation of the ribs are similarly oriented for all CVJ levels., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: Despite recent progress in motion capture technology, such as stereophotogrammetry based on the tracking of markers set on the subject, it remains challenging to develop a complete protocol for in-vivo functional evaluation of the hand. The current practical problems regarding small anatomical segments, such as the fingers, are mainly due to the high concentration of markers in a relatively reduced volume., Methods: This paper proposes a novel procedure for hand functional analysis by analysing finger behaviour along the main displacement plane simultaneously with combined motions. The objective was two-fold. For one thing, a novel data collection protocol was implemented, which includes specific setting of the motion capture system and the development of finger marker clusters. The second purpose of this study was to create a reference database of a healthy sample for further clinical investigation. Twenty healthy volunteers took part in the study. Analytical motions (flexion/extension and abduction/adduction) of all five fingers were recorded., Findings: Results showed good correspondence with the literature. Specific kinematic behaviour of each analysed joint is reported. Statistically significant differences were found between the right and left sides of the subjects for the flexion/extension movement only, between the finger joints and between the fingers for all movements. No significant difference was found between genders. A validation protocol was performed, which proved the validity of the presented methodology., Interpretation: The protocol appears suitable for further use in motion analysis and for musculoskeletal modelling of the hand. It will also be considered for clinical application., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The literature concerning quantification of costovertebral joint (CVJ) motion under in vivo conditions is scarce. Most papers concerning this topic are related to ex vivo loading conditions. In vivo protocols are available from the literature to determine rib and vertebra kinematics but new developments are needed to improve data processing concerning CVJ behaviour obtained from discrete breathing positions showing limiting ranges-of-motion and sensitive to noise. Data from previous work were used to implement a method analyzing mean helical axis (MHA) and pivot point parameters of the CVJ complexes. Several levels of noises were estimated within Monte-Carlo simulations to optimize MHA results. MHA parameters were then used to transform and define a CVJ-specific local coordinate system. This study proposes an improvement for CVJ kinematics processing and description from in vivo data obtained from computed tomography. This methodology emphasizes the possibility to work with variability of MHA parameters using Monte-Carlo procedures on anatomical landmark coordinates and to define a local coordinate system from this particular joint behaviour. Results from the CVJ joint model are closer to a hinge joint (secondary motions inferior to 3°) when anatomical frames are expressed from MHA orientation. MHA orientation and position data obtained from the proposed method are relevant according to angular dispersion obtained (from 7.5° to 13.9°) and therefore relevant to define behaviour of CVJ., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Despite the availability of the International Society of Biomechanics (ISB) recommendations for the orientation of anatomical frames, no consensus exists about motion representations related to finger kinematics. This paper proposes novel anatomical frames for motion representation of the phalangeal segments of the long fingers. A three-dimensional model of a human forefinger was acquired from a non-pathological fresh-frozen hand. Medical imaging was used to collect phalangeal discrete positions. Data processing was performed using a customized software interface ("lhpFusionBox") to create a specimen-specific model and to reconstruct the discrete motion path. Five examiners virtually palpated two sets of landmarks. These markers were then used to build anatomical frames following two methods: a reference method following ISB recommendations and a newly-developed method based on the mean helical axis (HA). Motion representations were obtained and compared between examiners. Virtual palpation precision was around 1mm, which is comparable to results from the literature. The comparison of the two methods showed that the helical axis method seemed more reproducible between examiners especially for secondary, or accessory, motions. Computed Root Mean Square distances comparing methods showed that the ISB method displayed a variability 10 times higher than the HA method. The HA method seems to be suitable for finger motion representation using discrete positions from medical imaging. Further investigations are required before being able to use the methodology with continuous tracking of markers set on the subject's hand., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: The costovertebral joint complex is mechanically involved in both respiratory function and thoracic spine stability. The thorax has been studied for a long time to understand its involvement in the physiological mechanism leading to specific gas exchange. Few studies have focused on costovertebral joint complex kinematics, and most of them focused on experimental in vitro analysis related to loading tests or global thorax and/or lung volume change analysis. There is however a clinical need for new methods allowing to process in vivo clinical data. This paper presents results from in vivo analysis of the costovertebral joint complex kinematics from clinically-available retrospective data., Methods: In this study, in vivo spiral computed tomography imaging data were obtained from 8 asymptomatic subjects at three different lung volumes (from total lung capacity to functional residual capacity) calibrated using a classical spirometer. Fusion methods including 3D modelling and kinematic analysis were used to provide 3D costovertebral joint complex visualization for the true ribs (i.e., first seven pairs of ribs)., Findings: The 3D models of the first seven pairs of costovertebral joint complexes were obtained. A continuous kinematics simulation was interpolated from the three discrete computerized tomography positions. Helical axis representation was also achieved., Interpretation: Preliminary results show that the method leads to meaningful and relevant results for clinical and pedagogical applications. Research in progress compares data from a sample of healthy volunteers with data collected from patients with cystic fibrosis to obtain new insights about the costovertebral joint complex range of motion and helical axis assessment in different pathological conditions., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: The number of in vivo clinical biomedical experiments based on computed tomography is increasing. International radiation-protection bodies are promoting the use of low-dose computed tomography to reduce radiation absorption by the subject undergoing imaging. On the other hand no data exist in the literature to quantify whether or not low-dose computed tomography would lead to a decrease of result quality when used for three-dimensional bone modeling and related measurements., Methods: This paper aimed at finding a consensus between minimal X-ray radiation of the subject, and satisfactory image data quality, especially for accurate three-dimensional bone modeling. Several standard computed tomography and low-dose computed tomography sequences were analyzed in three tests and statistically compared., Findings: Absence of significant difference between standard and low-dose computed sequences indicated that the low-dose setting would not produce less accurate three-dimensional models, while it decreased the effective X-ray dose up to 90% compared to standard settings., Interpretation: Low-dose computed tomography seems suitable for accurate three-dimensional bone modeling, while the related effective X-ray radiation is low. Such setting is therefore advised for any in vivo medical imaging aiming to collect bone data.

Background: Patients with cervical dystonia have been evaluated prospectively by the Toronto Western Spasmodic Torticollis Rating Scale and by cervical electrogoniometry., Methods: Nineteen patients with cervical dystonia were studied. The Toronto Scale interobserver reliability was evaluated by two observers. An electrogoniometer was used to quantify cervical range of motion and velocity. The correlation between goniometric measurements and clinical evaluation was calculated., Findings: The interobserver reliability was excellent for the total score (r(s) = 99) and good for the disability and the pain score (r > 0.88). However, global severity scale was shown to have a moderate reliability (r = 0.63) with r ranging from 0.37 to 0.98 for the individual items. The average loss of range of motion for flexion and extension, lateral bending and rotation was 18%, 12% and 21% respectively. For the velocity of movement, the average loss was proportionately greater than for the range of motion. (41%, 43% and 52% respectively). Correlation between the severity scale and range of motion was moderate but significant (r(s) = -0.52 to -0.67). Correlation between the Toronto severity score and the sum of movement velocities was significant for flexion-extension and lateral bending velocity sums (r(s) = -0.51; r(s) = -0.61). The lateral bending and rotation velocities were significantly correlated with pain and total scores (r(s) = -0.51). No significant correlation was observed for the disability score., Interpretation: Three-dimensional electrogoniometry is helpful to quantify the velocity of neck movements and range of motion in patients with cervical dystonia.

OBJECTIVE: The present study addresses elongation patterns of selected capsular wrist ligaments during two types of planar wrist motion. DESIGN. IN VITRO: continuous measurement of capsular ligament elongation using miniature displacement transducers. BACKGROUND: The function of the capsular wrist ligaments in carpal kinematics is still to be determined unambiguously. Most previous studies on carpal ligament behaviour were realised using X-ray stereophotogrammetric methods. METHODS: Elongation of the palmar radiolunate, radiocapitate and ulnocapitate ligaments, as well as of the dorsal radiotriquetral ligament during frontal and sagittal wrist motion were analysed in 10 anatomical specimens using miniature differential variable reluctance transducers. Wrist motion was tracked using a six-degree-of-freedom electrogoniometer. RESULTS AND CONCLUSIONS: In most instances, the elongation of these ligaments was similar for two motion modalities tested (guided by a rail or free) with, however, a trend to larger individual variations and smaller elongation during free motion for several ligaments. The capsular ligaments considered in this study displayed length changes inferior to 15% of the initial length. The individual elongation patterns and ranges were highly variable, contrasting with excellent intra-individual reproducibility.