Incidence, remission, and persistence of Raynaud's phenomenon in the general population of northern Sweden: a prospective study.

Background: Raynaud's phenomenon is common condition, but little is known about the natural course. The primary aim of this study was to determine the incidence, remission, and persistence proportions of Raynaud's phenomenon in the general population of northern Sweden. Secondary aims were to determine how individual and exposure factors affect the course of Raynaud's phenomenon, and to assess gender differences.

Manifestations of cold sensitivity - a case series.

To characterise cold sensitivity using a semi-structured interview, physical examination, thermal quantitative sensory testing (QST), and laser speckle contrast analysis (LASCA). Eight women and four men, ages 22-74, with cold sensitivity were interviewed and examined by an occupational physician. Thermal perception thresholds were established using QST, on the pulp of the index and little finger of the most affected hand.

Does the Femoral Head Size in Hip Arthroplasty Influence Lower Body Movements during Squats, Gait and Stair Walking? A Clinical Pilot Study Based on Wearable Motion Sensors.

A hip prosthesis design with larger femoral head size may improve functional outcomes compared to the conventional total hip arthroplasty (THA) design. Our aim was to compare the range of motion (RoM) in lower body joints during squats, gait and stair walking using a wearable movement analysis system based on inertial measurement units (IMUs) in three age-matched male groups: 6 males with a conventional THA (THAC), 9 with a large femoral head (LFH) design, and 8 hip- and knee-asymptomatic controls (CTRL). We hypothesized that the LFH design would allow a greater hip RoM, providing movement patterns more like CTRL, and a larger side difference in hip RoM in THAC when compared to LFH and controls.

Non-Ionizing Radiation in Swedish Health Care-Exposure and Safety Aspects.

The main aim of the study was to identify and describe methods using non-ionizing radiation (NIR) such as electromagnetic fields (EMF) and optical radiation in Swedish health care. By examining anticipated exposure levels and by identifying possible health hazards we also aimed to recognize knowledge gaps in the field. NIR is mainly used in health care for diagnosis and therapy.

Vibrotactile and thermal perception and its relation to finger skin thickness.

Objective: Quantitative measurements of vibrotactile and thermotactile perception thresholds (VPT and TPT, respectively) rely on responses from sensory receptors in the skin when mechanical or thermal stimuli are applied to the skin. The objective was to examine if there is a relation between skin thickness (epidermis and dermis) and VPT or TPT.

Methods: Perception thresholds were measured on the volar side of the fingertip on 148 male subjects, out of which 116 were manual workers exposed to hand-transmitted vibration and 32 were white-collar (office) workers.

Long-term effect of hand-arm vibration on thermotactile perception thresholds.

Background: Occupational exposure to hand-transmitted vibration (HTV) is known to cause neurological symptoms such as numbness, reduced manual dexterity, grip strength and sensory perception. The purpose of this longitudinal study was to compare thermotactile perception thresholds for cold (TPT) and warmth (TPT) among vibration exposed manual workers and unexposed white collar workers during a follow-up period of 16 years to elucidate if long-term vibration exposure is related to a change in TPT over time.

Methods: The study group consisted of male workers at a production workshop at which some of them were exposed to HTV.

Double-Sided Mechanical Shocks Provoke Larger Seated Postural Reactions Compared With Single-Sided Mechanical Shocks.

Study Design: Human volunteers were exposed experimentally to single-sided mechanical shocks (SSMS) and double-sided mechanical shocks (DSMS) while seated.

Objective: The aim of this study was to describe and contrast seated postural reactions due to SSMS or DSMS in healthy male adults.

Summary Of Background Data: Mechanical shocks to the body, caused when driving on irregular terrain, are suggested to be hazardous to the spine and may be associated with the reported musculoskeletal pain of the back and neck among professional drivers.

Neurovascular hand symptoms in relation to cold exposure in northern Sweden: a population-based study.

Purpose: To describe the self-reported ambient cold exposure in northern Sweden and to relate the level of cumulative cold exposure to the occurrence of sensory and vascular hand symptoms. We hypothesize that cold exposure is positively related to reporting such symptoms.

Methods: A questionnaire about cold exposure and related symptoms was sent out to 35,144 subjects aged 18-70 years and living in northern Sweden.

Is better preservation of eccentric strength after stroke due to altered prefrontal function?

Ventrolateral prefrontal cortex (VLPFC) is part of a network that exerts inhibitory control over the motor cortex (MC). Recently, we demonstrated that VLPFC was more activated during imagined maximum eccentric than during imagined concentric contractions in healthy participants. This was accompanied with lower activation levels within motor regions during imagined eccentric contractions.

Risk of hearing loss among workers with vibration-induced white fingers.

Background: We examined the risk of hearing loss for workers who use hand-held vibrating tools with vibration-induced white fingers (VWF) compared to workers without VWF.

Methods: Data on 184 participants from a 21-year cohort were gathered with questionnaires and measurements. The effects on hearing status of VWF, hand-arm vibration exposure, smoking habits, age and two-way interactions of these independent variables were examined with binary logistic regression.

Quantitatively measured tremor in hand-arm vibration-exposed workers.

Objectives: The aim of the present study was to investigate the possible increase in hand tremor in relation to hand-arm vibration (HAV) exposure in a cohort of exposed and unexposed workers.

Methods: Participants were 178 male workers with or without exposure to HAV. The study is cross-sectional regarding the outcome of tremor and has a longitudinal design with respect to exposure.

A prospective cohort study investigating an exposure-response relationship among vibration-exposed male workers with numbness of the hands.

Objective: The aim of this study was to investigate the exposure-response relationship of hand-arm vibration exposure to neurological symptoms (numbness) of the hand in a cohort of vibration-exposed workers.

Methods: The baseline cohort comprised 241 office and manual workers with and without exposure to hand-arm vibration. Numbness (the symptom or event) in the hand was assessed for all subjects at baseline and follow-ups after 5, 10, and 16 years.

Determinants explaining the variability of hand-transmitted vibration emissions from two different work tasks: grinding and cutting using angle grinders.

Background: There are numerous factors including physical, biomechanical, and individual that influence exposure to hand-transmitted vibration (HTV) and cause variability in the exposure measurements. Knowledge of exposure variability and determinants of exposure could be used to improve working conditions. We performed a quasi-experimental study, where operators performed routine work tasks in order to obtain estimates of the variance components and to evaluate the effect of determinants, such as machine-wheel combinations and individual operator characteristics.

Quantitative neurosensory findings, symptoms and signs in young vibration exposed workers.

Background: Long-term exposure to hand-held vibrating tools may cause the hand arm vibration syndrome (HAVS) including vibration induced white fingers and sensorineural symptoms. The aim was to study early neurosensory effects by quantitative vibrotactile and monofilament tests in young workers with hand-held vibration exposure.

Methods: This cross-sectional study consisted of 142 young, male machine shop and construction workers with hand-held exposure to vibrating tools.

Noise and hand-arm vibration exposure in relation to the risk of hearing loss.

The aim of this study was to examine the possible association of combined exposure of noise and hand-arm vibration (HAV) and the risk of noise-induced hearing loss. Workers in a heavy engineering industry were part of a dynamic cohort. Of these workers, 189 had HAV exposure, and their age and hearing status were recorded in the same year and were, therefore, included in the analysis.

Sound and vibration: effects on infants' heart rate and heart rate variability during neonatal transport.

Aim: To measure the effect of sound and whole-body vibration on infants' heart rate and heart rate variability during ground and air ambulance transport.

Methods: Sixteen infants were transported by air ambulance with ground ambulance transport to and from the airports. Whole-body vibration and sound levels were recorded and heart parameters were obtained by ECG signal.

Nerve conduction in relation to vibration exposure - a non-positive cohort study.

Background: Peripheral neuropathy is one of the principal clinical disorders in workers with hand-arm vibration syndrome. Electrophysiological studies aimed at defining the nature of the injury have provided conflicting results. One reason for this lack of consistency might be the sparsity of published longitudinal etiological studies with both good assessment of exposure and a well-defined measure of disease.

Vibrotactile perception and effects of short-term exposure to hand-arm vibration.

This study clarifies whether the established frequency weighting procedure for evaluating exposure to hand-transmitted vibration can effectively evaluate the temporary changes in vibrotactile perception thresholds due to pre-exposure to vibration. In addition, this study investigates the relationship between changes of the vibrotactile perception thresholds and the normalized energy-equivalent frequency-weighted acceleration. The fingers of 10 healthy subjects, five male and five female, were exposed to vibration under 16 conditions with a combination of different frequencies, intensities, and exposure times.

Influence of vibration exposure on tactile and thermal perception thresholds.

Aims: To establish if intermittent exposure to hand-transmitted vibration had the same effect as continuous exposure on the temporary response of finger tactile and thermal perception thresholds.

Methods: Two laboratory experiments were conducted. In each, 10 healthy subjects, five males and five females, participated.

Incidence of Raynaud's phenomenon in relation to hand-arm vibration exposure among male workers at an engineering plant a cohort study.

Background: The objective of this study was to assess the incidence of Raynaud's phenomenon in relation to hand-arm vibration exposure in a cohort consisting of male office and manual workers.

Methods: The baseline population consisted of 94 office and 147 manual workers at an engineering plant. Raynaud's phenomenon (RP) was assessed at baseline and at follow up (at 5, 10 and 15 years).

The effect of different warming methods on sensory nerve conduction velocity in shipyard workers occupationally exposed to hand-arm vibration.

Objectives: Segmental sensory nerve conduction velocity (SNCV) was measured from the wrists to the hands and digits in a population of 134 (126 men and 8 women) vibration-exposed shipyard workers following systemic warming using a bicycle ergometer. Results were compared to earlier nerve conduction tests, identical in execution, except that the warming process was segmental and cutaneous. The study was designed to investigate whether SNCVs, which were selectively slow in the fingers after segmental cutaneous (skin surface) warming, would be affected differently by systemic warming.

Musculoskeletal symptoms among young male workers and associations with exposure to hand-arm vibration and ergonomic stressors.

Objective: The overall aim of this study was to explore the association between incident musculoskeletal symptoms in the neck and upper limbs and exposure to hand-arm vibration and ergonomic stressors.

Methods: The study has a prospective design and data at baseline and follow-up was assessed by self-administered questionnaires. The study population consisted of students that had graduated from vocational high schools in 2001-2003 in northern and western Sweden and a total of 586 men responded to both the baseline and follow-up questionnaires.

Acute effects of vibration on thermal perception thresholds.

Objective: This study focuses on the acute effects of vibration and how vibrations influence the measures of the thermal perception thresholds during different vibration magnitudes, frequencies, and durations.

Methods: The fingers of ten healthy subjects, five males and five females, were exposed to vibration under 16 conditions with a combination of different frequency, intensity and exposure time. The vibration frequency was 31.

Syndromes from segmental vibration and nerve entrapment: observations on case definitions for carpal tunnel syndrome.

Objectives: The purpose of this paper is to assess the overlap and stability of two different case definitions of carpal tunnel syndrome CTS. The analysis considers the association between different case definitions and objective tests (sensory nerve conduction velocities, SNCVs and vibrotactile perception thresholds, TTS), and the natural history of CTS, in the context of two vibration-exposed cohorts.

Methods: Clinical CTS cases were defined in two ways: (1) by the study physician using fixed criteria, and; (2) by questionnaire and hand diagram.

Grading of sensorineural disturbances according to a modified Stockholm workshop scale using self-reports and QST.

Objective: The objective of the study was to apply, on a group of vibration exposed individuals, a proposed modification of the Stockholm Workshop scale for grading of sensorineural disorders by using self-reports and data from objective testing and to compare grading obtained through the two approaches.

Methods: The study group consisted of 126 young persons with different individual levels of hand-transmitted vibration exposures. Effect measurements included a self-administered questionnaire and vibrotactile perception measurements and Purdue Pegboard testing.