Leif Sandsjö - Academia.edu (original) (raw)

Papers by Leif Sandsjö

Research paper thumbnail of Subjective and objective evaluation of shoulder muscle fatigue

Ergonomics, 1994

In order to relate EMG signs of localized muscle fatigue to subjectively perceived muscle fatigue... more In order to relate EMG signs of localized muscle fatigue to subjectively perceived muscle fatigue, a study was undertaken on 20 healthy volunteers exposing their right trapezius muscle by raising the arm to 90 degrees of abduction. Every person performed two contractions: 0 kg hand load during 5 min and 2 kg hand load during 2.5 min. Surface EMG was recorded and analysed with respect to RMS amplitude and mean power frequency (MPF). Subjective muscle fatigue was estimated with a psychophysical rating scale (Borg's CR-10 Scale). At high load level we found a significant correlation between MPF and the CR-scores (r = -0.46), but at low load level there was no correlation. At high load level there was a linear decrease of MPF with increasing load dose, but at low load level the MPF did not change, despite significant subjective fatigue. There was a linear rise of the CR-score with increasing load dose, more pronounced at high load level. It was concluded, that at low load levels common in working life, MPF and subjective scores seem to provide different fatigue information. Moreover, the MPF did not seem to work as a valid estimator of muscle fatigue at this low load level. Caution is recommended if it is to be used in static low-load situations.

Research paper thumbnail of Clinical Experience with Modular Intelligent Arm Prosthesis Systems

Research paper thumbnail of Survey of Upper-Extremity Prosthesis Users in Sweden and the United Kingdom

JPO Journal of Prosthetics and Orthotics, 2007

Abstract A sample of 156 users of upper-limb prostheses from three fitting centers in Sweden and ... more Abstract A sample of 156 users of upper-limb prostheses from three fitting centers in Sweden and the United Kingdom participated in a survey that focused on user satisfaction. The survey was conducted via postal questionnaire. It included questions to record ...

Research paper thumbnail of The ToMPAW Modular Prosthesis: A Platform for Research in Upper-Limb Prosthetics

JPO Journal of Prosthetics and Orthotics, 2007

Current designs of commercial arm prostheses do not support a modular approach, meaning an arm cu... more Current designs of commercial arm prostheses do not support a modular approach, meaning an arm customized to the user becomes an assembly of disparate devices. The ToMPAW consortium was created to build on each participant's earlier experiences with limb fitting, orthopedic, technological engineering, and precision manufacturing techniques to create a whole-arm system from fingers to shoulder joint that was fully modular, both mechanically and electronically. A modular control system has been implemented that serves as a platform for research in upper-limb prosthetics. The modular approach enables each prosthesis to be easily modified, programmed, or extended according to each individual's needs, thus making it possible to try out different control schemes and mechanical realizations building on a small set of modules. Four experimental hands and two arm systems have had limited clinical use at two centers in the United Kingdom and Sweden. In addition, advanced arm control could be easily implemented with few changes to the system. A modular approach has the potential to cut limb-fitting costs by reducing the time needed for fitting and maintenance and the number of articles to be held in stock, either by the supplier or at the limb center.

Research paper thumbnail of Association entre audition et conditions psychosociales de travail chez les musiciens de rock/jazz

Association entre audition et conditions psychosociales de travail chez les musiciens de rock/jazz

Research paper thumbnail of Associations Between Hearing and Psychosocial Working Conditions in Rock/Jazz Musicians

Medical Problems of Performing Artists, 2003

A study on the assessment of hearing and hearing disorders in rock/jazz musicians concluded that ... more A study on the assessment of hearing and hearing disorders in rock/jazz musicians concluded that 74% of the musicians had some kind of disorder. The main hearing disorders found were pure-tone hearing loss, tinnitus (an acoustic sensation of sounds), hyperacusis (a hypersensitivity to low or moderate sound levels), and distortion (music sounds out of tune). Affected musicians often were able to give the exact time of the first appearance of the hearing disorders, which often was associated with a period of excessive sound exposure, high workload, or some form of emotional stress. The aim of this study was to explore associations between psychosocial work conditions, mental load, and hearing disorders in rock/jazz musicians. A total of 139 (43 women and 96 men) voluntarily participating rock/jazz musicians answered a questionnaire on psychosocial work conditions and mental load. The data were correlated to hearing and sex. The median age was 35 years in the women and 37 years in the ...

Research paper thumbnail of Monitoring of Brain Activity Using Textile Electrodes

Research paper thumbnail of Clinical evaluation of a myofeedback-based teletreatment service applied in the workplace: a randomized controlled trial

Journal of Telemedicine and Telecare, 2010

We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, ... more We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, pain-related disability and work ability. We also investigated the time investment/savings of this treatment with respect to conventional care. Sixty-five women with neck and shoulder pain at work participated in the study. Thirty-three took part in the teletreatment and 32 participated in a control group which

Research paper thumbnail of Investigating the conceptual phase of innovation: Communication and collaboration in multidisciplinary teams

Research paper thumbnail of Three-dimensional Fabrics as Medical Texiles

The number of 3D textile applications in medicine is rapidly increasing as new technology and pro... more The number of 3D textile applications in medicine is rapidly increasing as new technology and procedures are introduced in health care. A first estimate of current medical applications of both general and 3D textiles is presented based on the medical devices classification system established by the US Food and Drug Administration. The textile specifics for these applications are covered from a textile technique perspective where the different 3D weaving as well as knitting, braiding and non-woven techniques are described and how their properties they can contribute in medical applications. In addition, emerging opportunities based on smart textiles as part of textile systems are described on a general level. The strong application areas of 3D medical textiles, i.e. wound management, vascular grafting and scaffolding for tissue engineering are covered in detail both from the medical and textiles perspective. Finally, some future lines of development are suggested and a short discussi...

Research paper thumbnail of Organisatoriska förändringar inom offentlig tandvård - effekter på arbetsvillkor, produktivitet och tandläkarnas hälsa

Research paper thumbnail of Prognostic factors for the effect of a myofeedback-based teletreatment service

Journal of telemedicine and telecare, 2010

We investigated the potential prognostic factors for clinically relevant improvements in pain int... more We investigated the potential prognostic factors for clinically relevant improvements in pain intensity and pain-related disability after myofeedback-based teletreatment. Sixty-five female computer users, 56 female patients with whiplash-associated disorders and 18 female patients with non-specific neck and shoulder pain participated in the study. They received myofeedback-based teletreatment or usual treatment. Questionnaires concerning prognostic factors, pain and disability were completed before the start of the intervention (baseline) and at follow-ups at the end of the intervention, and after 3 and 6 months. Logistic regression analyses were performed in order to investigate prognostic factors for clinically relevant improvement. In the intervention group, improvement in pain intensity was predicted by baseline pain intensity. Baseline pain intensity and disability, and fear-avoidance and endurance related pain coping responses were prognostic factors for outcome in pain-relate...

Research paper thumbnail of Clinical evaluation of a myofeedback-based teletreatment service applied in the workplace: a randomized controlled trial

Journal of telemedicine and telecare, 2010

We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, ... more We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, pain-related disability and work ability. We also investigated the time investment/savings of this treatment with respect to conventional care. Sixty-five women with neck and shoulder pain at work participated in the study. Thirty-three took part in the teletreatment and 32 participated in a control group which continued with conventional care. Questionnaires were completed before the start of the intervention (baseline) and at initial follow-up (T0) and 3 months (T3) after the intervention ended. A general linear model analysis for repeated measurements showed an improvement in terms of pain and work ability for both groups taken together, with no differences between them. Non-parametric tests showed an intervention effect in pain-related disability for both groups together and no differences between them when tested at baseline, T0 and T3. The time saved in relation to conventional car...

Research paper thumbnail of Early phase requirements assessment of a teletreatment trial

Proceedings of the 2009 ACM symposium on Applied Computing - SAC '09, 2009

This paper presents the early phase requirements elicitation of a teletreatment trial and the ass... more This paper presents the early phase requirements elicitation of a teletreatment trial and the assessment of the requirements in respect of their importance to the trial and the feasibility of the corresponding adaptations of the telemedicine system within the trial project constraints. The elicitation approach and techniques adopt the particulars of the telemedicine working practices. The proposed approach not only

Research paper thumbnail of Work related perceived stress and muscle activity during standardized computer work among female computer users

Work, 2009

The current study investigated the associations between work-related perceived stress and surface... more The current study investigated the associations between work-related perceived stress and surface electromyographic (sEMG) parameters (muscle activity and muscle rest) during standardized simulated computer work (typing, editing, precision, and Stroop tasks). It was part of the European case-control study, NEW (Neuromuscular assessment in the Elderly Worker). The present cross-sectional study was based on a questionnaire survey and sEMG measurements among Danish and Swedish female computer users aged 45 or older (n=49). The results show associations between work-related perceived stress and trapezius muscle activity and rest during standardized simulated computer work, and provide partial empirical support for the hypothesized pathway of stress induced muscle activity in the association between an adverse psychosocial work environment and musculoskeletal symptoms in the neck and shoulder.

Research paper thumbnail of Requirements Elicitation in a Telemedicine Pain-treatment Trial

2009 17th IEEE International Requirements Engineering Conference, 2009

This paper presents the early phase requirements elicitation for a work-related neck-shoulder pai... more This paper presents the early phase requirements elicitation for a work-related neck-shoulder pain teletreatment trial and the assessment of those requirements in respect of their importance to the trial and the feasibility of the needed software adaptations of the telemedicine system within the constraints of the project organizing the trial. The elicitation adopts specific solutions and constraints that are typical for working practices in medicine. In particular, the contribution of this paper is its holistic approach in addressing the intertwining of the requirements elicitation and the trial design. Trial design defines the trial settings and the treatment protocols in a standardized way such that treatment efficacy can be evaluated based on evidence. A cyclic approach which applies a set of elicitation techniques and informal specification styles (e.g. tables and mock-ups) is adopted in order to converge on a set of requirements understood and agreed upon also by the trial designers, who are medical professionals, often unaware of formal methods, and who co-shape the telemedicine system.

Research paper thumbnail of Adaptive spatio-temporal filtering of disturbed ECGs: a multi-channel approach to heartbeat detection in smart clothing

Medical & Biological Engineering & Computing, 2007

Intermittent disturbances are common in ECG signals recorded with smart clothing: this is mainly ... more Intermittent disturbances are common in ECG signals recorded with smart clothing: this is mainly because of displacement of the electrodes over the skin. We evaluated a novel adaptive method for spatio-temporal filtering for heartbeat detection in noisy multi-channel ECGs including short signal interruptions in single channels. Using multi-channel database recordings (12-channel ECGs from 10 healthy subjects), the results showed that multi-channel spatio-temporal filtering outperformed regular independent component analysis. We also recorded seven channels of ECG using a T-shirt with textile electrodes. Ten healthy subjects performed different sequences during a 10-min recording: resting, standing, flexing breast muscles, walking and pushups. Using adaptive multi-channel filtering, the sensitivity and precision was above 97% in nine subjects. Adaptive multi-channel spatio-temporal filtering can be used to detect heartbeats in ECGs with high noise levels. One application is heartbeat detection in noisy ECG recordings obtained by integrated textile electrodes in smart clothing.

Research paper thumbnail of Changes in Cognitive-Behavioral Factors and Muscle Activation Patterns after Interventions for Work-Related Neck-Shoulder Complaints: Relations with Discomfort and Disability

Journal of Occupational Rehabilitation, 2007

Knowledge regarding the working mechanism of an intervention is essential for obtaining a better ... more Knowledge regarding the working mechanism of an intervention is essential for obtaining a better understanding of the intervention and contributes to optimize its outcome. This study aimed at investigating whether changes in cognitive-behavioral factors and muscle activation patterns after myofeedback training and ergonomic counseling were associated with outcome, in subjects with work-related musculoskeletal neck-shoulder complaints. Seventy-nine symptomatic subjects received either myofeedback with ergonomic counseling (Mfb/EC) or ergonomic counseling alone (EC). Outcome measures discomfort and disability, and process factors catastrophizing, pain control, fear-avoidance beliefs, and muscle activation patterns were assessed at baseline, after the interventions (T0), and at 3 months follow-up (T3). Mixed modeling techniques were used for analysis. Outcome in terms of discomfort and disability was generally comparable between both interventions. Catastrophizing was significantly reduced and fear-avoidance beliefs about work slightly increased after the interventions, but no consistent changes in muscle activation patterns were observed. Changes in discomfort were especially associated with changes in catastrophizing at T0 and T3, but R(2) was low (<0.14). Reduced catastrophizing at T0 and T3, and also reduced fear-avoidance beliefs about work at T3, were related to reduced disability (R(2) between 0.30 and 0.40). No differences between the two intervention groups were observed. Intervention effects were generally non-specific and findings suggested that cognitive-behavioral factors underlie the outcome of these interventions rather than changes in muscle activation patterns. Emphasizing these factors during therapy may increase the beneficial outcome of occupational interventions.

Research paper thumbnail of Effects of Ambulant Myofeedback Training and Ergonomic Counselling in Female Computer Workers with Work-Related Neck-Shoulder Complaints: A Randomized Controlled Trial

Journal of Occupational Rehabilitation, 2007

Objective: To investigate the effects of ambulant myofeedback training including ergonomic counse... more Objective: To investigate the effects of ambulant myofeedback training including ergonomic counselling (Mfb) and ergonomic counselling alone (EC), on work-related neck-shoulder pain and disability. Methods: Seventy-nine female computer workers reporting neck-shoulder complaints were randomly assigned to Mfb or EC and received four weeks of intervention. Pain intensity in neck, shoulders, and upper back, and pain disability, were measured at baseline, immediately after intervention, and at three and six months follow-up. Results: Pain intensity and disability had significantly decreased immediately after four weeks Mfb or EC, and the effects remained at follow up. No differences were observed between the Mfb and EC group for outcome and subjects in both intervention groups showed comparable chances for improvement in pain intensity and disability. Conclusions: Pain intensity and disability significantly reduced after both interventions and this effect remained at follow-up. No differences were observed between the two intervention groups. Springer 138 J Occup Rehabil (2007) 17:137-152 Picture 1 Myofeedback system: Harness and processing/storage unit Springer J Occup Rehabil (2007) 17:137-152

Research paper thumbnail of Prognostic Factors for Intervention Effect on Neck/Shoulder Symptom Intensity and Disability among Female Computer Workers

Journal of Occupational Rehabilitation, 2009

It has been suggested that treatments may be more effective when they are matched to patient char... more It has been suggested that treatments may be more effective when they are matched to patient characteristics. This study aimed at investigating potential prognostic factors for clinically relevant improvement in symptom intensity and symptom-related disability among employees with symptoms in the neck/shoulder area, receiving either ergonomics counseling or such counseling in combination with myofeedback training. A randomized controlled study was performed among female computer users aged 45 or older (n = 36). A clinical examination and a questionnaire survey were performed before inclusion in the study. Symptom intensity and disability was assessed using questionnaires before the start of the interventions (baseline) and at follow-ups directly after the end of the interventions (T0) and after 3 (T3) and 6 (T6) months. Logistic regression analyses were performed in order to assess prognostic factors for clinically relevant improvement in symptom intensity and disability. Improvement in symptom intensity was consistently predicted by symptom intensity at baseline. Diagnosis and stress-induced lack of muscular rest were prognostic factors for improvement in symptom intensity at short term follow-up. Baseline disability and passive coping consistently served as prognostic factors for outcome in disability. Few substantial differences were found between the interventions in terms of prognostic factors. Myofeedback training in combination with ergonomics counseling seem to be an especially beneficial tool for secondary prevention among employees with moderate levels of symptom intensity and symptom-related disability, who respond to work-related stress by increased/sustained muscle activation, and who tend to employ passive coping to deal with their neck/shoulder symptoms.

Research paper thumbnail of Subjective and objective evaluation of shoulder muscle fatigue

Ergonomics, 1994

In order to relate EMG signs of localized muscle fatigue to subjectively perceived muscle fatigue... more In order to relate EMG signs of localized muscle fatigue to subjectively perceived muscle fatigue, a study was undertaken on 20 healthy volunteers exposing their right trapezius muscle by raising the arm to 90 degrees of abduction. Every person performed two contractions: 0 kg hand load during 5 min and 2 kg hand load during 2.5 min. Surface EMG was recorded and analysed with respect to RMS amplitude and mean power frequency (MPF). Subjective muscle fatigue was estimated with a psychophysical rating scale (Borg's CR-10 Scale). At high load level we found a significant correlation between MPF and the CR-scores (r = -0.46), but at low load level there was no correlation. At high load level there was a linear decrease of MPF with increasing load dose, but at low load level the MPF did not change, despite significant subjective fatigue. There was a linear rise of the CR-score with increasing load dose, more pronounced at high load level. It was concluded, that at low load levels common in working life, MPF and subjective scores seem to provide different fatigue information. Moreover, the MPF did not seem to work as a valid estimator of muscle fatigue at this low load level. Caution is recommended if it is to be used in static low-load situations.

Research paper thumbnail of Clinical Experience with Modular Intelligent Arm Prosthesis Systems

Research paper thumbnail of Survey of Upper-Extremity Prosthesis Users in Sweden and the United Kingdom

JPO Journal of Prosthetics and Orthotics, 2007

Abstract A sample of 156 users of upper-limb prostheses from three fitting centers in Sweden and ... more Abstract A sample of 156 users of upper-limb prostheses from three fitting centers in Sweden and the United Kingdom participated in a survey that focused on user satisfaction. The survey was conducted via postal questionnaire. It included questions to record ...

Research paper thumbnail of The ToMPAW Modular Prosthesis: A Platform for Research in Upper-Limb Prosthetics

JPO Journal of Prosthetics and Orthotics, 2007

Current designs of commercial arm prostheses do not support a modular approach, meaning an arm cu... more Current designs of commercial arm prostheses do not support a modular approach, meaning an arm customized to the user becomes an assembly of disparate devices. The ToMPAW consortium was created to build on each participant's earlier experiences with limb fitting, orthopedic, technological engineering, and precision manufacturing techniques to create a whole-arm system from fingers to shoulder joint that was fully modular, both mechanically and electronically. A modular control system has been implemented that serves as a platform for research in upper-limb prosthetics. The modular approach enables each prosthesis to be easily modified, programmed, or extended according to each individual's needs, thus making it possible to try out different control schemes and mechanical realizations building on a small set of modules. Four experimental hands and two arm systems have had limited clinical use at two centers in the United Kingdom and Sweden. In addition, advanced arm control could be easily implemented with few changes to the system. A modular approach has the potential to cut limb-fitting costs by reducing the time needed for fitting and maintenance and the number of articles to be held in stock, either by the supplier or at the limb center.

Research paper thumbnail of Association entre audition et conditions psychosociales de travail chez les musiciens de rock/jazz

Association entre audition et conditions psychosociales de travail chez les musiciens de rock/jazz

Research paper thumbnail of Associations Between Hearing and Psychosocial Working Conditions in Rock/Jazz Musicians

Medical Problems of Performing Artists, 2003

A study on the assessment of hearing and hearing disorders in rock/jazz musicians concluded that ... more A study on the assessment of hearing and hearing disorders in rock/jazz musicians concluded that 74% of the musicians had some kind of disorder. The main hearing disorders found were pure-tone hearing loss, tinnitus (an acoustic sensation of sounds), hyperacusis (a hypersensitivity to low or moderate sound levels), and distortion (music sounds out of tune). Affected musicians often were able to give the exact time of the first appearance of the hearing disorders, which often was associated with a period of excessive sound exposure, high workload, or some form of emotional stress. The aim of this study was to explore associations between psychosocial work conditions, mental load, and hearing disorders in rock/jazz musicians. A total of 139 (43 women and 96 men) voluntarily participating rock/jazz musicians answered a questionnaire on psychosocial work conditions and mental load. The data were correlated to hearing and sex. The median age was 35 years in the women and 37 years in the ...

Research paper thumbnail of Monitoring of Brain Activity Using Textile Electrodes

Research paper thumbnail of Clinical evaluation of a myofeedback-based teletreatment service applied in the workplace: a randomized controlled trial

Journal of Telemedicine and Telecare, 2010

We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, ... more We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, pain-related disability and work ability. We also investigated the time investment/savings of this treatment with respect to conventional care. Sixty-five women with neck and shoulder pain at work participated in the study. Thirty-three took part in the teletreatment and 32 participated in a control group which

Research paper thumbnail of Investigating the conceptual phase of innovation: Communication and collaboration in multidisciplinary teams

Research paper thumbnail of Three-dimensional Fabrics as Medical Texiles

The number of 3D textile applications in medicine is rapidly increasing as new technology and pro... more The number of 3D textile applications in medicine is rapidly increasing as new technology and procedures are introduced in health care. A first estimate of current medical applications of both general and 3D textiles is presented based on the medical devices classification system established by the US Food and Drug Administration. The textile specifics for these applications are covered from a textile technique perspective where the different 3D weaving as well as knitting, braiding and non-woven techniques are described and how their properties they can contribute in medical applications. In addition, emerging opportunities based on smart textiles as part of textile systems are described on a general level. The strong application areas of 3D medical textiles, i.e. wound management, vascular grafting and scaffolding for tissue engineering are covered in detail both from the medical and textiles perspective. Finally, some future lines of development are suggested and a short discussi...

Research paper thumbnail of Organisatoriska förändringar inom offentlig tandvård - effekter på arbetsvillkor, produktivitet och tandläkarnas hälsa

Research paper thumbnail of Prognostic factors for the effect of a myofeedback-based teletreatment service

Journal of telemedicine and telecare, 2010

We investigated the potential prognostic factors for clinically relevant improvements in pain int... more We investigated the potential prognostic factors for clinically relevant improvements in pain intensity and pain-related disability after myofeedback-based teletreatment. Sixty-five female computer users, 56 female patients with whiplash-associated disorders and 18 female patients with non-specific neck and shoulder pain participated in the study. They received myofeedback-based teletreatment or usual treatment. Questionnaires concerning prognostic factors, pain and disability were completed before the start of the intervention (baseline) and at follow-ups at the end of the intervention, and after 3 and 6 months. Logistic regression analyses were performed in order to investigate prognostic factors for clinically relevant improvement. In the intervention group, improvement in pain intensity was predicted by baseline pain intensity. Baseline pain intensity and disability, and fear-avoidance and endurance related pain coping responses were prognostic factors for outcome in pain-relate...

Research paper thumbnail of Clinical evaluation of a myofeedback-based teletreatment service applied in the workplace: a randomized controlled trial

Journal of telemedicine and telecare, 2010

We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, ... more We evaluated the clinical effects of a myofeedback-based teletreatment service in terms of pain, pain-related disability and work ability. We also investigated the time investment/savings of this treatment with respect to conventional care. Sixty-five women with neck and shoulder pain at work participated in the study. Thirty-three took part in the teletreatment and 32 participated in a control group which continued with conventional care. Questionnaires were completed before the start of the intervention (baseline) and at initial follow-up (T0) and 3 months (T3) after the intervention ended. A general linear model analysis for repeated measurements showed an improvement in terms of pain and work ability for both groups taken together, with no differences between them. Non-parametric tests showed an intervention effect in pain-related disability for both groups together and no differences between them when tested at baseline, T0 and T3. The time saved in relation to conventional car...

Research paper thumbnail of Early phase requirements assessment of a teletreatment trial

Proceedings of the 2009 ACM symposium on Applied Computing - SAC '09, 2009

This paper presents the early phase requirements elicitation of a teletreatment trial and the ass... more This paper presents the early phase requirements elicitation of a teletreatment trial and the assessment of the requirements in respect of their importance to the trial and the feasibility of the corresponding adaptations of the telemedicine system within the trial project constraints. The elicitation approach and techniques adopt the particulars of the telemedicine working practices. The proposed approach not only

Research paper thumbnail of Work related perceived stress and muscle activity during standardized computer work among female computer users

Work, 2009

The current study investigated the associations between work-related perceived stress and surface... more The current study investigated the associations between work-related perceived stress and surface electromyographic (sEMG) parameters (muscle activity and muscle rest) during standardized simulated computer work (typing, editing, precision, and Stroop tasks). It was part of the European case-control study, NEW (Neuromuscular assessment in the Elderly Worker). The present cross-sectional study was based on a questionnaire survey and sEMG measurements among Danish and Swedish female computer users aged 45 or older (n=49). The results show associations between work-related perceived stress and trapezius muscle activity and rest during standardized simulated computer work, and provide partial empirical support for the hypothesized pathway of stress induced muscle activity in the association between an adverse psychosocial work environment and musculoskeletal symptoms in the neck and shoulder.

Research paper thumbnail of Requirements Elicitation in a Telemedicine Pain-treatment Trial

2009 17th IEEE International Requirements Engineering Conference, 2009

This paper presents the early phase requirements elicitation for a work-related neck-shoulder pai... more This paper presents the early phase requirements elicitation for a work-related neck-shoulder pain teletreatment trial and the assessment of those requirements in respect of their importance to the trial and the feasibility of the needed software adaptations of the telemedicine system within the constraints of the project organizing the trial. The elicitation adopts specific solutions and constraints that are typical for working practices in medicine. In particular, the contribution of this paper is its holistic approach in addressing the intertwining of the requirements elicitation and the trial design. Trial design defines the trial settings and the treatment protocols in a standardized way such that treatment efficacy can be evaluated based on evidence. A cyclic approach which applies a set of elicitation techniques and informal specification styles (e.g. tables and mock-ups) is adopted in order to converge on a set of requirements understood and agreed upon also by the trial designers, who are medical professionals, often unaware of formal methods, and who co-shape the telemedicine system.

Research paper thumbnail of Adaptive spatio-temporal filtering of disturbed ECGs: a multi-channel approach to heartbeat detection in smart clothing

Medical & Biological Engineering & Computing, 2007

Intermittent disturbances are common in ECG signals recorded with smart clothing: this is mainly ... more Intermittent disturbances are common in ECG signals recorded with smart clothing: this is mainly because of displacement of the electrodes over the skin. We evaluated a novel adaptive method for spatio-temporal filtering for heartbeat detection in noisy multi-channel ECGs including short signal interruptions in single channels. Using multi-channel database recordings (12-channel ECGs from 10 healthy subjects), the results showed that multi-channel spatio-temporal filtering outperformed regular independent component analysis. We also recorded seven channels of ECG using a T-shirt with textile electrodes. Ten healthy subjects performed different sequences during a 10-min recording: resting, standing, flexing breast muscles, walking and pushups. Using adaptive multi-channel filtering, the sensitivity and precision was above 97% in nine subjects. Adaptive multi-channel spatio-temporal filtering can be used to detect heartbeats in ECGs with high noise levels. One application is heartbeat detection in noisy ECG recordings obtained by integrated textile electrodes in smart clothing.

Research paper thumbnail of Changes in Cognitive-Behavioral Factors and Muscle Activation Patterns after Interventions for Work-Related Neck-Shoulder Complaints: Relations with Discomfort and Disability

Journal of Occupational Rehabilitation, 2007

Knowledge regarding the working mechanism of an intervention is essential for obtaining a better ... more Knowledge regarding the working mechanism of an intervention is essential for obtaining a better understanding of the intervention and contributes to optimize its outcome. This study aimed at investigating whether changes in cognitive-behavioral factors and muscle activation patterns after myofeedback training and ergonomic counseling were associated with outcome, in subjects with work-related musculoskeletal neck-shoulder complaints. Seventy-nine symptomatic subjects received either myofeedback with ergonomic counseling (Mfb/EC) or ergonomic counseling alone (EC). Outcome measures discomfort and disability, and process factors catastrophizing, pain control, fear-avoidance beliefs, and muscle activation patterns were assessed at baseline, after the interventions (T0), and at 3 months follow-up (T3). Mixed modeling techniques were used for analysis. Outcome in terms of discomfort and disability was generally comparable between both interventions. Catastrophizing was significantly reduced and fear-avoidance beliefs about work slightly increased after the interventions, but no consistent changes in muscle activation patterns were observed. Changes in discomfort were especially associated with changes in catastrophizing at T0 and T3, but R(2) was low (<0.14). Reduced catastrophizing at T0 and T3, and also reduced fear-avoidance beliefs about work at T3, were related to reduced disability (R(2) between 0.30 and 0.40). No differences between the two intervention groups were observed. Intervention effects were generally non-specific and findings suggested that cognitive-behavioral factors underlie the outcome of these interventions rather than changes in muscle activation patterns. Emphasizing these factors during therapy may increase the beneficial outcome of occupational interventions.

Research paper thumbnail of Effects of Ambulant Myofeedback Training and Ergonomic Counselling in Female Computer Workers with Work-Related Neck-Shoulder Complaints: A Randomized Controlled Trial

Journal of Occupational Rehabilitation, 2007

Objective: To investigate the effects of ambulant myofeedback training including ergonomic counse... more Objective: To investigate the effects of ambulant myofeedback training including ergonomic counselling (Mfb) and ergonomic counselling alone (EC), on work-related neck-shoulder pain and disability. Methods: Seventy-nine female computer workers reporting neck-shoulder complaints were randomly assigned to Mfb or EC and received four weeks of intervention. Pain intensity in neck, shoulders, and upper back, and pain disability, were measured at baseline, immediately after intervention, and at three and six months follow-up. Results: Pain intensity and disability had significantly decreased immediately after four weeks Mfb or EC, and the effects remained at follow up. No differences were observed between the Mfb and EC group for outcome and subjects in both intervention groups showed comparable chances for improvement in pain intensity and disability. Conclusions: Pain intensity and disability significantly reduced after both interventions and this effect remained at follow-up. No differences were observed between the two intervention groups. Springer 138 J Occup Rehabil (2007) 17:137-152 Picture 1 Myofeedback system: Harness and processing/storage unit Springer J Occup Rehabil (2007) 17:137-152

Research paper thumbnail of Prognostic Factors for Intervention Effect on Neck/Shoulder Symptom Intensity and Disability among Female Computer Workers

Journal of Occupational Rehabilitation, 2009

It has been suggested that treatments may be more effective when they are matched to patient char... more It has been suggested that treatments may be more effective when they are matched to patient characteristics. This study aimed at investigating potential prognostic factors for clinically relevant improvement in symptom intensity and symptom-related disability among employees with symptoms in the neck/shoulder area, receiving either ergonomics counseling or such counseling in combination with myofeedback training. A randomized controlled study was performed among female computer users aged 45 or older (n = 36). A clinical examination and a questionnaire survey were performed before inclusion in the study. Symptom intensity and disability was assessed using questionnaires before the start of the interventions (baseline) and at follow-ups directly after the end of the interventions (T0) and after 3 (T3) and 6 (T6) months. Logistic regression analyses were performed in order to assess prognostic factors for clinically relevant improvement in symptom intensity and disability. Improvement in symptom intensity was consistently predicted by symptom intensity at baseline. Diagnosis and stress-induced lack of muscular rest were prognostic factors for improvement in symptom intensity at short term follow-up. Baseline disability and passive coping consistently served as prognostic factors for outcome in disability. Few substantial differences were found between the interventions in terms of prognostic factors. Myofeedback training in combination with ergonomics counseling seem to be an especially beneficial tool for secondary prevention among employees with moderate levels of symptom intensity and symptom-related disability, who respond to work-related stress by increased/sustained muscle activation, and who tend to employ passive coping to deal with their neck/shoulder symptoms.