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Research paper thumbnail of Paths of the cervical instantaneous axis of rotation during active movements—patterns and reliability

Medical & Biological Engineering & Computing, Mar 19, 2020

The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive ... more The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive to changes in coordination and that has potential in the assessment of functional alterations. For its application in the clinical setting, normative patterns must be available, and its reliability must be established. The purpose of this work is to describe the continuous paths of the IHA during cyclic movements of flexion-extension (FE), lateral bending (LB), and axial rotation (AR) and to quantify their reliability. Fifteen healthy volunteers participated in the study; two repetitions were made on the same day (by different operators) and over an 8-day interval (by the same operator) to evaluate the inter-operator and inter-session reliability, respectively. The paths described by the IHA suggest a sequential movement of the vertebrae in the FE movement, with a large vertical displacement (mean, 10 cm). The IHA displacement in LB and AR movements are smaller. The paths described by the IHAs have a very high reliability for FE movement, although it is somewhat lower for LB and RA movements. The standard error of measurement (SEM) is less than 0.5 cm. These results show that the paths of the IHA are reliable enough to evaluate changes in the coordination of intervertebral movement.

Research paper thumbnail of Effect of non-specific neck pain on the path of the instantaneous axis of rotation of the neck during its flexion-extension movement

Musculoskeletal science and practice, Apr 1, 2023

Research paper thumbnail of Immediate Effects of a Single Session of Cervical Spine Manipulation on Cervical Movement Patterns in People With Nonspecific Neck Pain: A Randomized Controlled Trial

Journal of Manipulative and Physiological Therapeutics

Research paper thumbnail of Validation of a Dynamic Model of the Neck for Applications in Ergonomics and Functional Assessment

DYNA

A dynamic neck model is proposed for functional assessment or ergonomic studies using data obtain... more A dynamic neck model is proposed for functional assessment or ergonomic studies using data obtained from conventional biomechanical tools such as video photogrammetry and force platforms. The head and neck inertial parameters are obtained through regression equations and refined through a calibration process to improve accuracy. Head movement is recorded through video photogrammetry, where marker coordinates are used to calculate finite displacements, linear and angular velocities, and accelerations. An inverse dynamics approach is used to estimate the forces and moments at the C7 vertebral level and the generated muscle power. The model was validated through an experimental study with 30 participants, where its estimates were compared to the measurements obtained from a force platform. The comparison aimed to assess the accuracy and reliability of the model. The results show excellent agreement, with a correlation of 0.976 or higher and a standard error of less than 1% of the head ...

Research paper thumbnail of Effect of non-specific neck pain on the path of the instantaneous axis of rotation of the neck during its flexion-extension movement

Musculoskeletal Science and Practice

Research paper thumbnail of Experimental Validation in a Controlled Environment of a Methodology for Assessing the Dynamic Behavior of Railway Track Components

Machines, May 19, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Patrones de desplazamiento del eje instantáneo de rotación del cuello. Relación con el movimiento secuencial de las vértebras

XIV Congreso Iberoamericano de Ingeniería Mecánica, Sep 23, 2019

Research paper thumbnail of Flexo-extension analysis of the neck using artificial vision

arXiv: Image and Video Processing, 2020

In the treatment of cervical pain, several techniques that are commonly used cannot indicate the ... more In the treatment of cervical pain, several techniques that are commonly used cannot indicate the patient pain-intensity, but only can identify structural damage. The evaluation of this pain-intensity can be achieved analyzing the cervical joint kinematic variables of the three movements: flexo-extension, flexo-lateral and rotation. In this work we will study the reliability of the photogrametry technique through a low-cost camera, i.e., Kinect V1. The Kinect camera will acquire kinematic parameters of the flexo-extension movement from the neck joint. We will use artificial visionand depth/color image techniques to obtaining the trajectories of the technical (and anatomical) markers. A Kalman filter is employed to correct the continuous tracking of the technical markers to obtaining the spatial coordinates of each marker. The data is obtained from seven test-subjects, men and women physically healthy. The ages of the test-subjects are between 17 and 40 years. We compute the kinematic...

Research paper thumbnail of Análisis Del Eje Instantáneo De Rotación Del Movimiento De Flexo-Extensión Del Cuello Mediante Vídeo Análisis: Fiabilidad y Análisis De Errores

3C Tecnología_Glosas de innovación aplicadas a la pyme, 2018

, C. (2018). Análisis del eje instantáneo de rotación del movimiento de flexo-extensión del cuell... more , C. (2018). Análisis del eje instantáneo de rotación del movimiento de flexo-extensión del cuello mediante vídeo análisis: fiabilidad y análisis de errores. 3C Tecnología: glosas de innovación aplicadas a la pyme, 7(1), 79-92.

Research paper thumbnail of Análisis de Flexo-extensión del Cuello Mediante el Uso de Visión Artificial

Revista Politécnica

En el tratamiento del dolor cervical se emplean equipos y técnicas que no miden la intensidad del... more En el tratamiento del dolor cervical se emplean equipos y técnicas que no miden la intensidad del dolor del paciente, sino que únicamente permiten observar los daños estructurales de dicha región. Sin embargo, la evaluación de éste dolor se puede llevar a cabo al analizar las variables cinemáticas de los tres movimientos de la articulación cervical: flexo-extensión, flexo-lateral y rotación. En este trabajo estudiaremos la fiabilidad de la técnica de fotogrametría, mediante el uso de una cámara de bajo costo, denominado Kinect V1. La cámara Kinect adquirirá los parámetros cinemáticos del movimiento de flexo-extensión de la articulación del cuello y, técnicas de visión artificial y de procesamiento de imágenes de profundidad/color del sensor Kinect serán empleadas para obtener las trayectorias de los marcadores anatómicos y técnicos. Se utilizará un filtro de Kalman para corregir el seguimiento continuo de las trayectorias de los marcadores técnicos y, consecuentemente, las coordenad...

Research paper thumbnail of Paths of the cervical instantaneous axis of rotation during active movements—patterns and reliability

Medical & Biological Engineering & Computing

The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive ... more The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive to changes in coordination and that has potential in the assessment of functional alterations. For its application in the clinical setting, normative patterns must be available, and its reliability must be established. The purpose of this work is to describe the continuous paths of the IHA during cyclic movements of flexion-extension (FE), lateral bending (LB), and axial rotation (AR) and to quantify their reliability. Fifteen healthy volunteers participated in the study; two repetitions were made on the same day (by different operators) and over an 8-day interval (by the same operator) to evaluate the inter-operator and inter-session reliability, respectively. The paths described by the IHA suggest a sequential movement of the vertebrae in the FE movement, with a large vertical displacement (mean, 10 cm). The IHA displacement in LB and AR movements are smaller. The paths described by the IHAs have a very high reliability for FE movement, although it is somewhat lower for LB and RA movements. The standard error of measurement (SEM) is less than 0.5 cm. These results show that the paths of the IHA are reliable enough to evaluate changes in the coordination of intervertebral movement. Graphical abstract A video photogrammetry system is used to record the cyclic movements of the neck, from which the continuous trajectories of the associated instantaneous helical axis (IHA) are calculated. We have analyzed the movements of flexion-extension (FE), lateral flexion (LB), and axial rotation (AR) for a sample of 15 healthy subjects. The measurements have been repeated with two different operators (in the same session) and in two separate sessions (same operator). IHA displacement patterns have been obtained in each movement, and the reliability of the measurement of such IHA trajectories has been estimated.

Research paper thumbnail of Paths of the cervical instantaneous axis of rotation during active movements—patterns and reliability

Medical & Biological Engineering & Computing, Mar 19, 2020

The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive ... more The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive to changes in coordination and that has potential in the assessment of functional alterations. For its application in the clinical setting, normative patterns must be available, and its reliability must be established. The purpose of this work is to describe the continuous paths of the IHA during cyclic movements of flexion-extension (FE), lateral bending (LB), and axial rotation (AR) and to quantify their reliability. Fifteen healthy volunteers participated in the study; two repetitions were made on the same day (by different operators) and over an 8-day interval (by the same operator) to evaluate the inter-operator and inter-session reliability, respectively. The paths described by the IHA suggest a sequential movement of the vertebrae in the FE movement, with a large vertical displacement (mean, 10 cm). The IHA displacement in LB and AR movements are smaller. The paths described by the IHAs have a very high reliability for FE movement, although it is somewhat lower for LB and RA movements. The standard error of measurement (SEM) is less than 0.5 cm. These results show that the paths of the IHA are reliable enough to evaluate changes in the coordination of intervertebral movement.

Research paper thumbnail of Effect of non-specific neck pain on the path of the instantaneous axis of rotation of the neck during its flexion-extension movement

Musculoskeletal science and practice, Apr 1, 2023

Research paper thumbnail of Immediate Effects of a Single Session of Cervical Spine Manipulation on Cervical Movement Patterns in People With Nonspecific Neck Pain: A Randomized Controlled Trial

Journal of Manipulative and Physiological Therapeutics

Research paper thumbnail of Validation of a Dynamic Model of the Neck for Applications in Ergonomics and Functional Assessment

DYNA

A dynamic neck model is proposed for functional assessment or ergonomic studies using data obtain... more A dynamic neck model is proposed for functional assessment or ergonomic studies using data obtained from conventional biomechanical tools such as video photogrammetry and force platforms. The head and neck inertial parameters are obtained through regression equations and refined through a calibration process to improve accuracy. Head movement is recorded through video photogrammetry, where marker coordinates are used to calculate finite displacements, linear and angular velocities, and accelerations. An inverse dynamics approach is used to estimate the forces and moments at the C7 vertebral level and the generated muscle power. The model was validated through an experimental study with 30 participants, where its estimates were compared to the measurements obtained from a force platform. The comparison aimed to assess the accuracy and reliability of the model. The results show excellent agreement, with a correlation of 0.976 or higher and a standard error of less than 1% of the head ...

Research paper thumbnail of Effect of non-specific neck pain on the path of the instantaneous axis of rotation of the neck during its flexion-extension movement

Musculoskeletal Science and Practice

Research paper thumbnail of Experimental Validation in a Controlled Environment of a Methodology for Assessing the Dynamic Behavior of Railway Track Components

Machines, May 19, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Research paper thumbnail of Patrones de desplazamiento del eje instantáneo de rotación del cuello. Relación con el movimiento secuencial de las vértebras

XIV Congreso Iberoamericano de Ingeniería Mecánica, Sep 23, 2019

Research paper thumbnail of Flexo-extension analysis of the neck using artificial vision

arXiv: Image and Video Processing, 2020

In the treatment of cervical pain, several techniques that are commonly used cannot indicate the ... more In the treatment of cervical pain, several techniques that are commonly used cannot indicate the patient pain-intensity, but only can identify structural damage. The evaluation of this pain-intensity can be achieved analyzing the cervical joint kinematic variables of the three movements: flexo-extension, flexo-lateral and rotation. In this work we will study the reliability of the photogrametry technique through a low-cost camera, i.e., Kinect V1. The Kinect camera will acquire kinematic parameters of the flexo-extension movement from the neck joint. We will use artificial visionand depth/color image techniques to obtaining the trajectories of the technical (and anatomical) markers. A Kalman filter is employed to correct the continuous tracking of the technical markers to obtaining the spatial coordinates of each marker. The data is obtained from seven test-subjects, men and women physically healthy. The ages of the test-subjects are between 17 and 40 years. We compute the kinematic...

Research paper thumbnail of Análisis Del Eje Instantáneo De Rotación Del Movimiento De Flexo-Extensión Del Cuello Mediante Vídeo Análisis: Fiabilidad y Análisis De Errores

3C Tecnología_Glosas de innovación aplicadas a la pyme, 2018

, C. (2018). Análisis del eje instantáneo de rotación del movimiento de flexo-extensión del cuell... more , C. (2018). Análisis del eje instantáneo de rotación del movimiento de flexo-extensión del cuello mediante vídeo análisis: fiabilidad y análisis de errores. 3C Tecnología: glosas de innovación aplicadas a la pyme, 7(1), 79-92.

Research paper thumbnail of Análisis de Flexo-extensión del Cuello Mediante el Uso de Visión Artificial

Revista Politécnica

En el tratamiento del dolor cervical se emplean equipos y técnicas que no miden la intensidad del... more En el tratamiento del dolor cervical se emplean equipos y técnicas que no miden la intensidad del dolor del paciente, sino que únicamente permiten observar los daños estructurales de dicha región. Sin embargo, la evaluación de éste dolor se puede llevar a cabo al analizar las variables cinemáticas de los tres movimientos de la articulación cervical: flexo-extensión, flexo-lateral y rotación. En este trabajo estudiaremos la fiabilidad de la técnica de fotogrametría, mediante el uso de una cámara de bajo costo, denominado Kinect V1. La cámara Kinect adquirirá los parámetros cinemáticos del movimiento de flexo-extensión de la articulación del cuello y, técnicas de visión artificial y de procesamiento de imágenes de profundidad/color del sensor Kinect serán empleadas para obtener las trayectorias de los marcadores anatómicos y técnicos. Se utilizará un filtro de Kalman para corregir el seguimiento continuo de las trayectorias de los marcadores técnicos y, consecuentemente, las coordenad...

Research paper thumbnail of Paths of the cervical instantaneous axis of rotation during active movements—patterns and reliability

Medical & Biological Engineering & Computing

The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive ... more The instantaneous helical axis (IHA) is a characteristic of neck movement that is very sensitive to changes in coordination and that has potential in the assessment of functional alterations. For its application in the clinical setting, normative patterns must be available, and its reliability must be established. The purpose of this work is to describe the continuous paths of the IHA during cyclic movements of flexion-extension (FE), lateral bending (LB), and axial rotation (AR) and to quantify their reliability. Fifteen healthy volunteers participated in the study; two repetitions were made on the same day (by different operators) and over an 8-day interval (by the same operator) to evaluate the inter-operator and inter-session reliability, respectively. The paths described by the IHA suggest a sequential movement of the vertebrae in the FE movement, with a large vertical displacement (mean, 10 cm). The IHA displacement in LB and AR movements are smaller. The paths described by the IHAs have a very high reliability for FE movement, although it is somewhat lower for LB and RA movements. The standard error of measurement (SEM) is less than 0.5 cm. These results show that the paths of the IHA are reliable enough to evaluate changes in the coordination of intervertebral movement. Graphical abstract A video photogrammetry system is used to record the cyclic movements of the neck, from which the continuous trajectories of the associated instantaneous helical axis (IHA) are calculated. We have analyzed the movements of flexion-extension (FE), lateral flexion (LB), and axial rotation (AR) for a sample of 15 healthy subjects. The measurements have been repeated with two different operators (in the same session) and in two separate sessions (same operator). IHA displacement patterns have been obtained in each movement, and the reliability of the measurement of such IHA trajectories has been estimated.