hig.sePublications
Change search
Refine search result
1 - 10 of 10
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard-cite-them-right
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • sv-SE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • de-DE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Kalezic, Nebojsa
    et al.
    University of Gävle, Belastningsskadecentrum.
    Åsell, Malin
    Sandlund, Jonas
    Lyskov, Eugene
    University of Gävle, Belastningsskadecentrum.
    Djupsjöbacka, Mats
    University of Gävle, Belastningsskadecentrum.
    Physiological Reactivity to Laboratory Stressors in Patients With Low Back Pain and Whiplash Associated Disorder2004In: Proceedings of the 44th Annual Meeting of The Society for Psychophysiological Research, 2004, p. S75-Conference paper (Other academic)
  • 2.
    Lyskov, Eugene
    et al.
    University of Gävle, Belastningsskadecentrum.
    Kalezic, Nebojsa
    University of Gävle, Belastningsskadecentrum.
    Sandlund, Jonas
    University of Gävle, Belastningsskadecentrum.
    Hamberg, Jern
    Physiological responsiveness to stressing test in patients with neck pain2004In: International Congress on Chronic Pain and Dysfunction after Whiplash and other Traumatic Neck Injuries, Gävle: Gävle University Press , 2004, p. 49-51Conference paper (Refereed)
  • 3.
    Sandlund, Jonas
    University of Gävle, Centre for Musculoskeletal Research.
    Position-matching and goal-directed reaching acuity of the upper limb in chronic neck pain: associations to self-rated characteristics2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Neck-shoulder pain is common in the general population and causes individual suffering as well as large costs for the society. Despite substantial efforts, there is still a shortage of methods for objective diagnosis and effective rehabilitation of such disorders. Thus, there is a great need to develop and evaluate new methods for these purposes. From clinical observations and recent research it has become evident that sensorimotor control can be impaired in people with neck-shoulder pain and may play a role in the pathogenesis of these disorders. In this thesis, precision of goal-directed arm movements, a previously unstudied class of movements in neck-shoulder pain, was studied.

    The main aim of the thesis was to investigate if people with chronic neck-shoulder pain have a reduced acuity of goal-directed movements of the upper extremity. A second aim was to study associations between reduced movement acuity and symptoms and self-rated characteristics.

    Upper limb repositioning acuity was assessed in blindfolded subjects performing tests of active, ipsilateral position-matching of two target positions (long and short) in movements constrained to horizontal-adduction of the shoulder. Reduced repositioning acuity, suggesting impaired shoulder proprioception, was found for both subjects with whiplash associated disorders (WAD) and non-specific neck-shoulder pain (NS). The degree of reduced acuity was shown to correlate with self-ratings of various health concepts, functioning and pain. A conspicuous finding was that there was lack of correlation between short and long target errors, along with the fact that associations between repositioning acuity and symptoms and self-rated characteristics was primarily found for the short target position.

    To further investigate the possible mechanisms underlying the disassociation between long and short target movement control, the association pattern between the outcome of several variants of ipsilateral position matching and velocity-discrimination tests, were studied. It was found that the perception of limb position in position-matching of short target locations appears to be predominantly based on movement velocity, whereas perception of limb position in movements to longer target locations may rely on a location-based perception mechanism.

    To extend the research on reduced upper extremity proprioception in neck-shoulder pain to a more natural movement situation, acuity of goal-directed pointing including full vision and 3D multi-joint movements was investigated in WAD, NS and healthy controls subjects. The results revealed a reduced acuity for both neck-pain groups. Moreover, distinct associations between end-point acuity and neck movement problems, limitations of some physical functions and, in WAD; some aspects of pain, were revealed.

    The findings demonstrate that the precision of upper limb movements can be reduced in chronic neck-shoulder pain. Substantial associations with symptoms and self-rated functioning suggest a clinical relevance of acuity measures of goal-directed arm movements. The findings indicate that tests of sensorimotor control can provide objective measures that may be useful in biopsychosocial profiling and characterization of subgroups of patients with chronic neck-shoulder pain, and that training target control of goal-directed movements should be considered in rehabilitation programs of people with these disorders.

  • 4.
    Sandlund, Jonas
    et al.
    University of Gävle, Belastningsskadecentrum (t.o.m. 051231).
    Djupsjöbacka, Mats
    University of Gävle, Belastningsskadecentrum (t.o.m. 051231).
    Ryhed, B
    Hamberg, Jern
    University of Gävle, Belastningsskadecentrum (t.o.m. 051231).
    Johansson, Håkan
    University of Gävle, Belastningsskadecentrum (t.o.m. 051231).
    Reduced shoulder proprioception in patients with whiplash associated disorders (WAD)2004In: 8th International Federation of Orthopaedic Manipulative Therapists' Conference, Cape Town, South Africa: March 21-26, 2004, 2004Conference paper (Other academic)
    Abstract [en]

    INTRODUCTION: Chronic whiplash associated disorders (WAD) are frequent in medical practice and are presented as a complex picture of neck -and shoulder pain along with numerous other symptoms. However, objective findings at physical examination are usually weak and thus the diagnosis of WAD is mostly based on the medical history and interpretation of personal information. Lately attention has focused on proprioceptive disturbances. Reasonably, vertigo, dizziness and fumbling often reported for WAD patients may be associated with alterations in proprioception. Our lab showed that experimentally induced pain directly impacts muscle spindle activity (MSA) in the muscles primarily affected, as well as in contralateral muscles. Since proprioception is mostly dependent upon MSA, pain originating from the neck region could potentially impair proprioception throughout the upper limbs. To validate proprioceptive testing as a diagnostic tool, the aims of the present study were to investigate: (1) shoulder proprioception, in the ability to reproduce a target position, in WAD patients compared to healthy controls; and (2) possible correlations between the degree of position matching error and subjective rating of health status, disability, self-efficacy and pain. METHODS: Participants were 38 WAD patients and 41 healthy subjects. From a start position of 50 degrees to the sagittal plane, shoulder horizontal-adduction movements of the right glenohumural joint to target positions of 18 and 30 degrees were conducted. The variable error (VE) of the position matching was used to assess the outcome. The patients also completed reports of their general health status (SF-36), disability due to pain (Pain disability index), pain-ratings (VAS) and self-efficacy beliefs (Self efficacy scale). RESULTS: The results showed a significantly higher VE in the WAD-group compared to the controls (p .< 0.001). VE and scores of the self-reports was found to correlate for all the questionnaires used. However, this was true only for the shorter (18 deg) target position. Put together in a step-wise multiple regression model the questionnaires could explain 46 percent of the position matching variance (p < 0.001), but again only when short target positions were focused. DISCUSSION AND CONCLUSION: A reduced ability to reproduce shoulder positions after active displacement implies a disturbance of the sensory motor function of patients with chronic WAD. According to our hypothesis, reduced proprioceptive function of muscle spindles could be responsible for this negative effect on precision and quality of movements. The correlation between position- matching errors and self-reports suggests that this in turn could be reflected in the person's everyday life. Correlations only for shorter target positions indicate that the control of different movement extents may depend on partly different mechanisms. The results may stimulate further research and the possibility of using proprioceptive tests to confirm symptoms and subjective disability in various musculo-skeletal disorders.

  • 5.
    Sandlund, Jonas
    et al.
    University of Gävle, Centre for Musculoskeletal Research.
    Djupsjöbacka, Mats
    University of Gävle, Centre for Musculoskeletal Research.
    Ryhed, Bengt
    Hamberg, Jern
    Björklund, Martin
    University of Gävle, Centre for Musculoskeletal Research.
    Predictive and discriminative value of shoulder proprioception tests for patients with whiplash-associated disorders2006In: Journal of Rehabilitation Medicine, ISSN 1650-1977, E-ISSN 1651-2081, Vol. 38, no 1, p. 44-49Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To evaluate whether patients suffering from whiplash-associated disorders have impaired shoulder proprioception and whether the acuity of shoulder proprioception is reflected in the patients' symptoms and self-rated function. DESIGN: A comparative group design, including a correlation design for the patient group. SUBJECTS: Patients with chronic whiplash-associated disorders (n=37) and healthy subjects (n=41). The groups were matched for age and gender. METHODS: All subjects underwent a shoulder proprioception test involving active ipsilateral arm position-matching. Group difference was evaluated by multiple analysis of variance and analysis of variance. The patient group completed questionnaires addressing functioning and health and performed pain ratings. Associations between proprioceptive acuity and self-rated functioning and symptoms were studied by correlation and regression analyses. RESULTS: The patient group showed significantly lower acuity of shoulder proprioception. Moderate correlations were found between proprioceptive acuity and questionnaire scores representing physical functioning, so that low proprioceptive acuity was associated with low self-rated physical functioning. Scores representing pain-intensity did not correlate with proprioceptive acuity. CONCLUSION: The results show that, at the group level, patients with whiplash-associated disorders have impaired shoulder proprioception. The clinical relevance of this finding is strongly supported by the association between shoulder proprioceptive acuity and self-rated functioning in the patient group.

  • 6.
    Sandlund, Jonas
    et al.
    University of Gävle, Centre for Musculoskeletal Research. Department of Surgery and Perioperative Sciences, Division of Sports Medicine, University of Umeå, Alfta, Sweden; Alfta Research Foundation, Alfta, Sweden.
    Röijezon, Ulrik
    University of Gävle, Centre for Musculoskeletal Research. Department of Community Medicine and Rehabilitation, Physiotherapy, University of Umeå, Umeå, Sweden; Alfta Research Foundation, Alfta, Swede.
    Björklund, Martin
    University of Gävle, Centre for Musculoskeletal Research. Alfta Research Foundation, Alfta, Swede.
    Djupsjöbacka, Mats
    University of Gävle, Centre for Musculoskeletal Research.
    Acuity of goal-directed arm movements to visible targets in chronic neck pain2008In: Journal of Rehabilitation Medicine, ISSN 1650-1977, E-ISSN 1651-2081, Vol. 40, no 5, p. 366-374Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To evaluate end-point acuity in goal-directed arm movements in subjects with chronic neck pain, while taking the trade-off between speed and accuracy into account, and to evaluate associations between reduced acuity and self-rated characteristics. DESIGN: Single-blinded, controlled, comparative group study. SUBJECTS: Forty-five subjects with chronic non-traumatic, non-specific neck pain (n = 24) and whiplash-associated disorders (n = 21). Healthy subjects served as controls (n = 22). The groups were age- and sex-matched. METHODS: Subjects performed fast and accurate pointing movements to a visual target. Group differences in end-point variability, controlled for peak velocity, were evaluated. Associations between end-point variability and self-rated symptoms, functioning, self-efficacy and kinesiophobia were analysed. RESULTS: End-point acuity, controlled for peak velocity, was reduced for both neck-pain groups. Similar spatial error patterns across all groups indicated no direction-specific reduction. For both neck-pain groups, associations were found between end-point acuity and neck movement deficits, physical functioning and, in whiplash, also balance and pain. CONCLUSION: Acuity of goal-directed arm movements can be reduced in chronic neck pain. Associations between acuity and self-rated characteristics support the clinical validity of the results and indicate that impaired neck function contributes to reduced end-point acuity. The results can be of importance for characterization and rehabilitation of neck disorders.

  • 7.
    Sandlund, Jonas
    et al.
    University of Gävle, Centre for Musculoskeletal Research.
    Röijezon, Ulrik
    University of Gävle, Centre for Musculoskeletal Research.
    Björklund, Martin
    University of Gävle, Centre for Musculoskeletal Research.
    Djupsjöbacka, Mats
    University of Gävle, Centre for Musculoskeletal Research.
    Acuity of goal-directed reaching movements to visible targets in chronic neck disorders2007In: Sixth International Scientific Conference on Prevention of Work-Related Musculoskeletal Disorders, 2007, p. 10-Conference paper (Other academic)
  • 8.
    Sandlund, Jonas
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research. Department of Community Medicine and Rehabilitation, Physiotherapy, Umeå University, Umeå, Sweden.
    Srinivasan, Divya
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Heiden, Marina
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Mathiassen, Svend Erik
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Differences in motor variability among individuals performing a standardized short-cycle manual task2017In: Human Movement Science, ISSN 0167-9457, E-ISSN 1872-7646, Vol. 51, p. 17-26Article in journal (Refereed)
    Abstract [en]

    Motor variability (MV) has been suggested to be a determinant of the risk for developing musculoskeletal disorders in repetitive work. In this study we examined whether individuals consistently differed in the extent of motor variability when performing a standardized short-cycle manual task. On three separate days, arm kinematics was recorded in 14 healthy subjects performing a pipetting task, transferring liquid from a pick-up tube to eight target tubes with a cycle time of 2.8 s. Cycle-to-cycle standard deviations (SD) of a large selection of shoulder and elbow kinematic variables, were processed using principal component analysis (PCA). Thereafter, between-subjects and between-days (within-subject) variance components were calculated using a random effects model for each of four extracted principal components. The results showed that MV differed consistently between subjects (95% confidence intervals of the between-subjects variances did not include zero) and that subjects differed consistently in MV between days. Thus, our results support the notion that MV may be a consistent personal trait, even though further research is needed to verify whether individuals rank consistently in MV even across tasks. If so, MV may be a candidate determinant of the risk of developing fatigue and musculoskeletal disorders in repetitive occupational work.

  • 9.
    Sandlund, Jonas
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research. Department for Community Medicine and Rehabilitation, Umeå University.
    Srinivasan, Divya
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Mathiassen, Svend Erik
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Consistency of individual motor variability patterns in repetitive precision work2015In: Physiotherapy, ISSN 0031-9406, E-ISSN 1873-1465, Vol. 101, no Suppl. 1, p. e1334-e1335Article in journal (Other academic)
    Abstract [en]

    Background:

    A longstanding hypothesis in physical therapy and occupational research is that workers repeating a task very stereotypically will be more prone to develop musculoskeletal disorders than workers that manage to vary postures and loads. Increased movement variability (MV), presumably, modify tissue loads, distribute stresses more equally, and thus reduce the cumulative load on any particular tissue. A handful of studies of MV have indicated less overuse injuries and faster recovery from musculoskeletal pain disorders. Even when repeating strictly controlled tasks individuals may differ in motor consistency, some showing higher levels of MV than others. However, whether the extent of MV is indeed a consistent individual trait across different tasks and different days is not known.

    Purpose:

    To investigate whether individual profiles of MV is stabile between days, the consistency of MV patterns from kinematic recordings, repeated across three days, was studied when performing repetitive upper-extremity precision work.

    Methods:

    A laboratory-based simulation of precision work; a 'pipetting' task paradigm, was developed in which liquid was repeatedly transferred from one tube to another, with a cycle time of 2.8s. Fourteen healthy female subjects, aged 20-45 years, right-handed and with experience in pipetting participated on 3 different days under identical conditions. Kinematic data were obtained using an electromagnetic motion capture system (FASTRAK). MV in shoulder elevation, elbow flexion and shoulder-elbow coordination were operationalized using cycle-to-cycle standard deviations across 20 pipetting cycles of kinematics parameters including joint range of motion, average and peak velocities, time to peak velocities, average angle and phase. Multivariate analysis was conducted using principal component analysis (PCA) (SIMCA+P, 12.0) to analyze relationships among variables and individual patterns in the data matrix of the recordings from day1. Thereafter, in order to confirm the observed structure of inter-individual MV patterns, classification of the data from day2 and day3 was performed using the parameters of the model from day1.

    Results:

    Four PCA components (Eigenvalues>1) accounted for 80 percent of the total variance in the model for day1. In the subsequent prediction model where data from day2 and 3 were projected into the model of day1, all subject observations except one could be predicted with 95% confidence (Hotelling T2). And individual data scores from all three days were clustered in relative proximity to each other, indicating consistency in MV between days.

    Conclusion(s):

    The findings indicate, even in this small and homogenous sample of young healthy females, that there may indeed be consistent individual traits in motor variability. A next step would be to answer whether these traits remain consistent if work factors such as work pace or precision are altered, and whether individual profiles of MV are associated with physiological responses related to risk for developing musculoskeletal disorders.

    Implications:

    Consistency of individual MV patterns substantiate previous notions that some people appear prone to repeat themselves while others tend to vary their motor behavior when performing the same task. Assessment of MV by physical therapists in research and practice could be valuable to further explore and address the relation of MV and musculoskeletal health.

  • 10.
    Srinivasan, Divya
    et al.
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Sandlund, Jonas
    Umeå University, Department of Community Medicine and Rehabilitation, Physiotherapy.
    Mathiassen, Svend Erik
    University of Gävle, Faculty of Health and Occupational Studies, Department of Occupational and Public Health Sciences, Occupational health science. University of Gävle, Centre for Musculoskeletal Research.
    Motor variability traits among individuals performing repetitive precision work2014In: Proceedings of the 11th International Symposium on Human Factors in Organizational Design and Management (ODAM), and 46th Annual Nordic Ergonomics Society Conference (NES): Selected and peer reviewed papers / [ed] Ole Broberg et al., Santa Monica, CA: The IEA Press , 2014, p. 987-989Conference paper (Refereed)
    Abstract [en]

    Motor variability (MV) refers to the intrinsic variability naturally present in the motor control system. Occurring even in the simplest movements, it is usually manifested as a difference in joint movements, joint coordination and/or muscle activities between successive repeats of a task which are identical in performance. Contrary to the traditional view that MV is detrimental to performance, it is now widely accepted that MV may actually have an important functional role in skill acquisition, and that skilled performance may, actually, be associated with increased MV. Further, MV is related to pain and fatigue, and may play a decisive role in rehabilitation (reviewed in Srinivasan & Mathiassen 2012). Hypothetically, individuals with a larger MV would be better protected against overuse injuries, and recover faster after disorders affecting motor performance. However, whether the extent of MV is, indeed, a consistent individual trait across different tasks is not known.    

    The purpose of this study was to let individuals perform a laboratory-based simulation of repetitive upper-extremity precision work and determine:

    (i)             Whether it is possible to systematically classify individuals according to the size of their MV in repetitive work;

    (ii)            Whether classification of individuals in one working condition on one day persists even when some work-factors are slightly changed, and between different days when they perform the same work.

    Repetitive pipetting with a cycle time of 2.8s was performed in the laboratory by a group of 14 healthy female subjects, aged 20-45 years, right-handed and experienced in pipetting, on 3 different days under identical protocol and experimental conditions. Work factors such as work-pace, precision and cognitive load (on top of the pipetting work) were manipulated within each day. Kinematic data were obtained using electromagnetic motion capture systems (FASTRAK).

    MV in shoulder elevation, elbow flexion and shoulder-elbow coordination were operationalized using cycle-to-cycle standard deviations of motor parameters such as peak velocities, time lag of peak velocities, phase angle and inter-segmental phase angle. The resulting traits in individuals and the consistency of those traits across tasks and days will be presented.

1 - 10 of 10
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard-cite-them-right
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • sv-SE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • de-DE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf