Defining malnutrition in persons with spinal cord injury - does the Global Criteria for Malnutrition work?

Background and aims: Physiologic and metabolic changes following spinal cord injury (SCI) lead to an increased risk of malnutrition. The Global Leadership Initiative on Malnutrition (GLIM) is a three-step approach to diagnose malnutrition: 1) screening; 2) phenotypic and etiological criteria; and 3) malnutrition severity. The main aim of this study was to assess malnutrition in patients with SCI, according to the GLIM criteria. Methods: Patients with SCI (≥ 18 years) admitted to rehabilitation were included. Anthropometrics, food intake, and inflammation were assessed on admission. Fat-free mass index (FFMI) was estimated from bioimpedance analysis. Malnutrition was diagnosed by the GLIM criteria, using the Malnutrition Universal Screening Tool (MUST) as the first step screening tool. Sensitivity and specificity analyses were performed. Results: In total, 66 patients were assessed (50 men) with a mean age of 51.4 (± 17.4) years and median time since injury was 37.5 (10-450) days. The mean body mass index was 24.7 (± 4.2) kg/m2, and 1-month involuntary weight loss was 5.7 (± 4.4)%. FFMI for men was 17.3 (± 1.9) and for women 15.3 (± 1.6) kg/m2. Forty-one patients (62%) were malnourished according to the GLIM criteria: 27 moderately and 14 severely malnourished. MUST was not able to detect malnutrition risk of nine patients, giving a moderate agreement (kappa 0.66), with a sensitivity of 0.78 and a specificity of 0.92 compared to the GLIM diagnosis. Conclusions: In this cross-sectional study, 62% of subacute SCI patients were malnourished according to the GLIM criteria. The screening tool MUST showed moderate agreement with the GLIM criteria and did not detect risk of all patients with a malnutrition diagnosis. The clinical implications of these findings need further investigation.

The relationship between balance control and thigh muscle strength and muscle activity in persons with incomplete spinal cord injury.

STUDY DESIGN: Cross-sectional study. OBJECTIVES: A spinal cord injury (SCI) can compromise the ability to maintain sufficient balance control during activities in an upraised position. The objective of the study was to explore the relationship between balance control and muscle strength and muscle activation in the lower extremities in persons with incomplete SCI (iSCI). SETTING: Sunnaas Rehabilitation Hospital, Norway. METHODS: Thirteen men and two women with iSCI and 15 healthy, matched controls were included. Performance of the Berg Balance Scale (BBS) short version (7 items) was used to indicate balance control. Maximal voluntary contraction (MVC) was performed to measure isometric muscle strength in thigh muscles (knee extension/flexion), while surface electromyography (EMG) was measured from M. Vastus Lateralis and M. Biceps Femoris. The relative activation of each muscle during each of the BBS tasks was reported as the percentage of the maximal activation during the MVC (%EMGmax). RESULTS: The iSCI participants had a significantly lower BBS sum score and up to 40% lower muscle strength in knee- flexion and extension compared to the matched healthy controls. They also exhibited a significantly higher %EMGmax, i.e. a higher muscle activation, during most of the balance tests. Univariate regression analysis revealed a significant association between balance control and mean values of %EMGmax in Biceps Femoris, averaged over the seven BBS tests. CONCLUSIONS: The participants with iSCI had poorer balance control, reduced thigh muscle strength and a higher relative muscle activation in their thigh muscles, during balance-demanding activities.

Effectiveness of robot-assisted arm exercise on arm and hand function in stroke survivors - A systematic review and meta-analysis.

Objective: To examine the treatment effect of commercially available robotic-assisted devices, compared to traditional occupational- and physiotherapy on arm and hand function in persons with stroke. Methods: A systematic literature search was conducted in Medline, EMBASE, CINAHL and Cochrane Central Register of Controlled Trials up to January 2022. Randomized controlled trials (RCT's) involving persons with stroke of all ages and robot-assisted exercise as method for arm and hand function, compared to traditional therapy methods were included. Three authors performed the selection independently. The quality of evidence across studies was assessed using GRADE. Results: Eighteen RCT's were included in the study. A random effects meta-analysis showed a statistically significantly higher treatment effect in the robotic-assisted exercise group (p=<0.0001) compared to the traditional treatment group, with a total effect size of 0.44 (CI = 0.22-0.65). Heterogeneity was high, measured with I2 of 65%). Subgroup analyses showed no significant effects of the type of robotic device, treatment frequency or duration of intervention. Discussion and conclusion: Even though the analysis showed significant improvement in arm and hand function in favor of the robotic-assisted exercise group, the results in this systematic review should be interpreted with caution. This is due to high heterogeneity among the studies included and the presence of possible publication bias. Results of this study highlight the need for larger and more methodological robust RCT's, with a focus on reporting training intensity during robotic exercise.

Health System's Role in Facilitating Health Service Access among Persons with Spinal Cord Injury across 22 Countries.

(1) Background: Despite efforts to improve access to health services, between- and within-country access inequalities remain, especially for individuals with complex disabling conditions like spinal cord injury (SCI). Persons with SCI require regular multidisciplinary follow-up care yet experience more access barriers than the general population. This study examines health system characteristics associated with access among persons with SCI across 22 countries. (2) Methods: Study data are from the International Spinal Cord Injury Survey with 12,588 participants with SCI across 22 countries. Cluster analysis was used to identify service access clusters based on reported access restrictions. The association between service access and health system characteristics (health workforce, infrastructure density, health expenditure) was determined by means of classification and regression trees. (3) Results: Unmet needs were reported by 17% of participants: lowest (10%) in Japan, Spain, and Switzerland (cluster 1) and highest (62%) in Morocco (cluster 8). The country of residence was the most important factor in facilitating access. Those reporting access restrictions were more likely to live in Morocco, to be in the lowest income decile, with multiple comorbidities (Secondary Conditions Scale (SCI-SCS) score > 29) and low functioning status (Spinal Cord Independence Measure score < 53). Those less likely to report access restriction tended to reside in all other countries except Brazil, China, Malaysia, Morocco, Poland, South Africa, and South Korea and have fewer comorbidities (SCI-SCS < 23). (4) Conclusions: The country of residence was the most important factor in facilitating health service access. Following the country of residence, higher income and better health were the most important facilitators of service access. Health service availability and affordability were reported as the most frequent health access barriers.

Ageing, functioning patterns and their environmental determinants in the spinal cord injury (SCI) population: A comparative analysis across eleven European countries implementing the International Spinal Cord Injury Community Survey.

BACKGROUND: As the European population with Spinal Cord Injury (SCI) is expected to become older, a better understanding of ageing with SCI using functioning, the health indicator used to model healthy ageing trajectories, is needed. We aimed to describe patterns of functioning in SCI by chronological age, age at injury and time since injury across eleven European countries using a common functioning metric, and to identify country-specific environmental determinants of functioning. METHODS: Data from 6'635 participants of the International Spinal Cord Injury Community Survey was used. The hierarchical version of Generalized Partial Credit Model, casted in a Bayesian framework, was used to create a common functioning metric and overall scores. For each country, linear regression was used to investigate associations between functioning, chronological age, age at SCI or time since injury for persons with para- and tetraplegia. Multiple linear regression and the proportional marginal variance decomposition technique were used to identify environmental determinants. RESULTS: In countries with representative samples older chronological age was consistently associated with a decline in functioning for paraplegia but not for tetraplegia. Age at injury and functioning level were associated, but patterns differed across countries. An association between time since injury and functioning was not observed in most countries, neither for paraplegia nor for tetraplegia. Problems with the accessibility of homes of friends and relatives, access to public places and long-distance transportation were consistently key determinants of functioning. CONCLUSIONS: Functioning is a key health indicator and the fundament of ageing research. Enhancing methods traditionally used to develop metrics with Bayesian approach, we were able to create a common metric of functioning with cardinal properties and to estimate overall scores comparable across countries. Focusing on functioning, our study complements epidemiological evidence on SCI-specific mortality and morbidity in Europe and identify initial targets for evidence-informed policy-making.

Does stronger primary care improve access to health services for persons with spinal cord injury? Evidence from eleven European countries.

OBJECTIVE: To determine the association between the strength of primary care and perceived access to follow-up care services among persons with chronic spinal cord injury (SCI). DESIGN: Data analysis of the International Spinal Cord Injury (InSCI) cross-sectional, community-based questionnaire survey conducted in 2017-2019. The association between the strength of primary care (Kringos et al., 2003) and access to health services was established using univariable and multivariable logistic regression analysis, adjusted for socio-demographic and health status characteristics. SETTING: Community in eleven European countries: France, Germany, Greece, Italy, Lithuania, the Netherlands, Norway, Poland, Romania, Spain and Switzerland. PARTICIPANTS: 6658 adults with chronic SCI. INTERVENTION: None. OUTCOME MEASURES: Share of persons with SCI that reported unmet healthcare needs as a measure of access. RESULTS: Twelve percent of the participants reported unmet healthcare needs: the highest in Poland (25%) and lowest in Switzerland and Spain (7%). The most prevalent access restriction was service unavailability (7%). Stronger primary care was associated with lower odds of reporting unmet healthcare needs, service unavailability, unaffordability and unacceptability. Females, persons of younger age and lower health status, had higher odds of reporting unmet needs. CONCLUSIONS: In all investigated countries, persons with chronic SCI face access barriers, especially with service availability. Stronger primary care for the general population was also associated with better health service access for persons with SCI, which argues for further primary care strengthening.

Impacts of Bladder Managements and Urinary Complications on Quality of Life: Cross-sectional Perspectives of Persons With Spinal Cord Injury Living in Malaysia, Indonesia, and Thailand.

BACKGROUND: The impact of bladder care and urinary complications on quality of life in persons with spinal cord injury who have neurogenic lower urinary tract dysfunction has not been elucidated, especially in those living in low-resource countries. METHODS: This multinational cross-sectional survey was conducted in rehabilitation facilities in Malaysia, Indonesia, and Thailand. Community-dwelling adults with traumatic or nontraumatic spinal cord injury participating in the International Spinal Cord Injury Community Survey from 2017 to 2018 were enrolled. Data regarding bladder management/care, presence of bladder dysfunction, urinary tract infection, and quality of life score were extracted from the International Spinal Cord Injury Community Survey questionnaire. The impact of bladder care and urinary complications on quality of life was determined using univariable and multivariable regression analysis. RESULTS: Questionnaires from 770 adults were recruited for analysis. After adjusting for all demographic and spinal cord injury-related data, secondary conditions, as well as activity and participation factors, urinary tract infection was an independent negative predictive factor of quality of life score ( P = 0.007, unstandardized coefficients = -4.563, multivariable linear regression analysis, enter method). CONCLUSIONS: Among bladder care and urinary complication factors, urinary tract infection is the only factor negatively impacting quality of life. These results address the importance of proper bladder management and urinary tract infection prevention in persons with spinal cord injury to improve their quality of life.

Physical Health Conditions in Persons with Spinal Cord Injury Across 21 Countries Worldwide.

OBJECTIVES: To describe the 3-month prevalence and correlates of self-reported physical health conditions in persons with spinal cord injury (SCI) worldwide. STUDY DESIGN: Multinational cross-sectional survey. SUBJECTS: Community-living persons with traumatic or non-traumatic SCI aged >18 years from 21 countries representing all the 6 World Health Organization regions. METHODS: The study used data from 11,058 participants in the International SCI Community Survey (InSCI). The survey, based on the International Classification of Functioning, Disability and Health (ICF) Core Sets for SCI, was conducted in 2017-19 simultaneously in the participating countries. The health conditions were reported on a modified version of the SCI Secondary Conditions Scale. RESULTS: Overall, 95.8% of the participants reported having experienced 1 or more health problems secondary to SCI. Having pain was the most prevalent problem (77.3%), followed by spasticity/muscle spasms (73.5%) and sexual dysfunction (71.3%), and the least prevalent was respiratory problems (28.8%). The participants reported a mean of 7.4 concurrent health conditions. Unmet healthcare needs, being a smoker, being a female, having a complete lesion, and a traumatic injury exhibited significant associations with comorbidity. CONCLUSION: Physical health problems secondary to SCI are extremely common worldwide and demand investment in appropriate management, medical care and preventative measures.

Are Social Relationships an Underestimated Resource for Mental Health in Persons Experiencing Physical Disability? Observational Evidence From 22 Countries.

Objectives: As advancing evidence on modifiable resources to support mental health in persons experiencing physical disabilities is of particular importance, we investigate whether structural and functional social relationships relate to mental health in people with spinal cord injury (SCI). Methods: Data from 12,330 participants of the International SCI community survey (InSCI) from 22 countries were analyzed. Structural (partnership status, living situation) and functional aspects of social relationships (belongingness, relationship satisfaction, problems with social interactions) were regressed on the SF-36 mental health index (MHI-5), stratified by countries and for the total sample using multilevel models. Results: Functional aspects of social relationships were consistently related to clinically relevant higher MHI-5 scores and lower risk of mental health disorders (MHI-5 >56). Structural social relationships were inconsistently associated with mental health in our sample. Conclusion: This study provides evidence that functional aspects of social relationships are important resources for mental health. Interventions to establish and maintain high quality relationships should be considered in public health interventions and rehabilitation programs to reduce long-term mental health problems in persons experiencing physical disabilities.

Health inequalities and income for people with spinal cord injury. A comparison between and within countries.

Income and health are related in a bi-directional manner, whereby level of income affects health and vice versa. People in poorer households tend to experience worse health status and higher mortality rates than people in wealthier households, and, at the same time, having poor health could restrict workability leading to less income. This gap exists in almost every country, and it is more pronounced in more unequal countries and in vulnerable populations, such as people experiencing disability. The goal of this paper is to estimate the health-income gap in people with a Spinal Cord Injury (SCI), which is a chronic health condition often associated with multiple comorbidities that leads to disability. As data on mortality is inexistent, to estimate the health-income gap for persons with SCI, this paper uses two health outcomes: the number of years a person has lived with the injury, and a comorbidity index. Data was obtained from the International Spinal Cord Injury survey (InSCI), which is the first worldwide survey on community-dwelling persons with SCI. To compare across countries, the health outcomes were adjusted through hierarchical models, accounting for country fixed-effects, individual characteristics such as age and gender, and injury characteristics (cause, type and degree). Our results suggest that for the years living with SCI, the gap varies from 1 to 6 years between the lowest and the highest income groups. The main driver of such a difference is the cause of injury, where injuries caused by work accidents showed the biggest gap. Similarly, for the comorbidity index, persons with SCI in poorer deciles reported significantly more comorbidities, forty times more, than people in richer deciles.

Changes in cardiorespiratory fitness and activity levels over the first year after discharge in ambulatory persons with recent incomplete spinal cord injury.

STUDY DESIGN: Secondary analysis of a clinical trial. OBJECTIVES: To investigate changes in cardiorespiratory fitness (CRF) and activity level in ambulatory persons with SCI during the first year after discharge from inpatient rehabilitation. SETTING: Sunnaas Rehabilitation Hospital, Nesoddtangen, Norway. METHODS: Thirty persons with incomplete SCI, all community walkers (25 males and 5 females, 18-69 years old) were recruited to a clinical trial of a 12 weeks home-based aerobic exercise program of either high or moderate intensity. During the last week of inpatient rehabilitation (baseline), participants performed a maximal exercise test on a treadmill (peak oxygen uptake; peak VO2) and a 6-min walking test (6MWT). Also, total daily energy expenditure (TDEE) and daily amount of steps were measured continuously during 7 days in the participants' homes. All tests were repeated after 3 and 12 months (post tests). RESULTS: Twenty of the 30 clinical trial participants performed baseline and both posttests and are included in this secondary analysis. We found no statistically significant between-group differences in the time course over the first year of either peak VO2, 6MWT, or physical activity outcomes. Therefore, data from both exercise groups and the control group were merged for secondary analyses, revealing statistically significant increase over time in peak VO2, 6MWT, and TDEE. The increase over time in the average daily steps did not reach statistical significance. CONCLUSIONS: Ambulatory persons with SCI were able to increase their CRF levels over the first year after discharge from inpatient rehabilitation, despite a minimal increase in activity levels.

Quality of Life and the Health System: A 22-Country Comparison of the Situation of People With Spinal Cord Injury.

OBJECTIVE: To analyze and compare how performance of the health system are linked to the self-reported quality of life (QOL) of people with spinal cord injury (SCI) in 22 countries participating in the International Spinal Cord (InSCI) community survey. DESIGN: Cross-sectional survey. SETTING: Twenty-two countries representing all 6 World Health Organization regions, community setting. PARTICIPANTS: Persons (N=12,591) with traumatic or nontraumatic SCI aged ≥18 years. INTERVENTIONS: Not applicable. MAIN OUTCOMES: Self-reported satisfaction on several indicators that include: health, ability to perform daily activities, oneself, personal relationships, and living conditions. A total score of QOL was calculated using these 5 definitions. RESULTS: The most important indicators for self-reported QOL of persons with SCI were social attitudes and access to health care services, followed by nursing care, access to public spaces, the provision of vocational rehabilitation, transportation, medication, and assistive devices. In general, persons with SCI living in higher-income countries reported a higher QOL than people in lower-income countries, with some exceptions. The top performing country was The Netherlands with an estimated median QOL of 66% (on a 0%-100% scale). CONCLUSIONS: The living situation of people with SCI is highly influenced by the performance of the health system. Measuring and comparing health systems give accountability to a country's citizens, but it also helps to determine areas for improvement.

Human skeletal muscle fiber type percentage and area after reduced muscle use: A systematic review and meta-analysis.

The main objective of this systematic review was to examine the effect of reduced muscle activity on the relative number of type 1 muscle fibers (%) in the human vastus lateralis muscle. Other objectives were changes in type 2A and 2X percentages and muscle fiber cross-sectional area. We conducted systematic literature searches in eight databases and included studies assessing type 1 fiber percentage visualized by ATPase or immunohistochemical staining before and after a period (≥14 days) of reduced muscle activity. The reduced muscle activity models were detraining, leg unloading, and bed rest. Forty-two studies comprising 451 participants were included. Effect sizes were calculated as the mean difference between baseline and follow-up and Generic Inverse Variance tests with random-effects models were used for the weighted summary effect size. Overall, the mean type 1 muscle fiber percentage was significantly reduced after interventions (-1.94%-points, 95% CI [-3.37, -0.51], P = .008), with no significant differences between intervention models (P = .86). Meta-regression showed no effect of study duration on type 1 fiber percentage (P = .98). Conversely, the overall type 2X fiber percentage increased after reduced muscle activity (P < .001). The CSA of the muscle fiber types decreased after the study period (all P-values < 0.001) with greater reductions in type 2 than type 1 fibers (P < .001). The result of this meta-analysis display that the type 1 muscle fiber percentage decrease as a result of reduced muscle activity, although the effect size is relatively small.

Effectiveness of training with motion-controlled commercial video games on hand and arm function in young people with cerebral palsy: A systematic review and meta-analysis.

OBJECTIVE: To examine the effect of motion-controlled commercial video games compared with traditional occupational and physiotherapy methods for hand and arm function in persons of all ages with cerebral palsy. DATA SOURCES: A systematic literature search was conducted in Medline, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, OTseeker and PEDro for randomized controlled trials involving persons with cerebral palsy using motion-controlled commercial video games as a training method for hand and arm function, compared with traditional therapy. STUDY SELECTION AND DATA EXTRACTION: Screening, data-extraction, risk of bias and quality assessment was carried out independently by 2 of the authors. The risk of bias of each study was assessed using the Cochrane Collaborations Risk of Bias Tool. The quality of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE). DATA SYNTHESIS: Eight randomized controlled trials, with a total of 262 participants, were included. A random effects meta-analysis showed a statistically significant difference between the groups in favour of motion-controlled commercial video games. The quality of the evidence was, however, rated as very low. CONCLUSION: Despite a significantly greater improvement in hand and arm function in favour of motion-controlled commercial video games, the results of this review should be interpreted with caution with regards to high risk of bias and the low strength of evidence. There is a need for high-powered studies on the effectiveness of training with motion-controlled commercial video games for persons with cerebral palsy, especially in adults.

Effects of moderate- and high-intensity aerobic training program in ambulatory subjects with incomplete spinal cord injury-a randomized controlled trial.

STUDY DESIGN: Randomized controlled trial. OBJECTIVES: To investigate if high-intensity interval training (HIIT) exhibits a higher increase in physical capacity and activity levels compared to moderate-intensity training (MIT) and treatment as usual. SETTING: Sunnaas Rehabilitation Hospital. METHODS: Thirty ambulatory participants with incomplete spinal cord injury (SCI) were recruited at discharge from inpatient rehabilitation. Two intervention groups performed a 12-week individual training program at home by walking or running, depending on their physical ability. The MIT group was instructed to exercise three times a week at 70% of maximal heart rate (HRmax), while the HIIT group was instructed to exercise twice a week at 85-95% of HRmax. The control group received treatment as usual. Pre- and post-tests consisted of maximal exercise testing on a treadmill (peak oxygen uptake (peak VO2)), a 6-min walking test (6MWT), and 7 days of continuously activity monitoring (total daily energy expenditure (TDEE) and daily number of steps). RESULTS: The HIIT, MIT, and control groups showed an increase in peak VO2 from pre- to post-test. However, no between-group difference in physical capacity (peak VO2 and 6MWT) and physical activity levels (TDEE and daily number of steps) were found between these groups. CONCLUSIONS: Performing HIIT did not exhibit a greater increase in physical capacity and activity levels than performing MIT or "treatment as usual" in ambulatory participants with SCI. Further studies are needed to elucidate both short- and long-term effects of HIIT and MIT in this SCI subpopulation.

Study Protocol of the International Spinal Cord Injury (InSCI) Community Survey.

OBJECTIVE: The Learning Health System for Spinal Cord Injury (LHS-SCI) is an initiative embedded in the World Health Organization's (WHO's) Global Disability Plan and requires the statistical collection of data on the lived experience of persons with SCI to consequently formulate recommendations and policies. The International Spinal Cord Injury (InSCI) community survey has been developed as an initial step to gain information about the lived experience of persons with SCI within and across diverse nations. DESIGN: InSCI is a multinational community survey based on the International Classification of Functioning, Disability and Health Core Sets for SCI and involves 28 countries from all six WHO regions. The study will be implemented in 2017. Overall aims, guiding principles on sampling strategies, data collection modes, and reminder management are described. CONCLUSIONS: InSCI will be the first survey to be conducted simultaneously in many countries and in all six WHO world regions that identifies the factors associated with functioning, health, and well-being of persons living with SCI. Expected results of the survey will be used for the basis of conducting stakeholder dialogs for policy reforms designed to improve the functioning, health maintenance, and well-being of persons with SCI.

Reliability of three-dimensional kinematic gait data in adults with spinal cord injury.

OBJECTIVES: Three-dimensional gait analysis has been recommended as part of standardized gait assessment in people with spinal cord injury. The aim was to investigate inter- and intra-session reliabilities of gait kinematics in people with spinal cord injury. METHODS: Fifteen adults with spinal cord injury performed two test sessions on separate days. Six infrared cameras, 16 reflective markers and the Plug-in gait model were used. For each subject, five gait trials from both sessions were included. The Gait Profile Score and the Gait Variable Score were used as kinematic outcome measures. Reliability was assessed with intraclass correlation coefficient, standard error of measurement, minimal detectable change, and Bland-Altman plots. RESULTS: Inter-session intraclass correlation coefficient for all variables was >0.82 and standard error of measurement <1.8°, except for hip rotation. Intra-session reliability was found to be high (≥0.78) and slightly better than that for inter-session. Minimal detectable change for all variables was <4.7°, except for hip rotation. CONCLUSIONS: The high inter- and intra-session reliabilities indicate small intrinsic variation of gait. Thus, three-dimensional gait analysis seems to be a reliable tool to evaluate kinematic gait in adults with spinal cord injury, but caution is warranted especially for hip rotation evaluation.

Coffee intake and development of pain during computer work.

BACKGROUND: The present study sought to determine if subjects who had consumed coffee before performing a simulated computer office-work task found to provoke pain in the neck and shoulders and forearms and wrists exhibited different time course in the pain development than the subjects who had abstained from coffee intake. FINDINGS: Forty eight subjects all working fulltime, 22 with chronic shoulder and neck pain and 26 healthy pain-free subjects, were recruited to perform a computer-based office-work task for 90 min. Nineteen (40%) of the subjects had consumed coffee (1/2 -1 cup) on average 1 h 18 min before start. Pain intensity in the shoulders and neck and forearms and wrists was rated on a visual analogue scale every 15 min throughout the work task.During the work task the coffee consumers exhibited significantly lower pain increase than those who abstained from coffee. CONCLUSIONS: Subjects who had consumed coffee before starting a pain provoking office work task exhibited attenuated pain development compared with the subjects who had abstained from coffee intake. These results might have potentially interesting implications of a pain-modulating effect of caffeine in an everyday setting. However, studies with a double blind placebo controlled randomized design are needed.

Deep tissue hyperalgesia after computer work.

Background and purpose A growing number of people are using computers. Shoulder and neck pain occur commonly during computer work. Peripheral and central sensitization may play a major role in establishing and maintaining several chronic pain conditions. We have previously reported that a 90 min simulated computer office-work induced substantial pain in the shoulders and neck. We hypothesized that the development of pain during the computer work may be related to sensitization. The aim of the present study was to examine if the 90 min computer work induced deep tissue muscle hyperalgesia manifested as altered pressure pain thresholds (PPTs). Methods Twenty-two subjects with chronic shoulder and neck pain (pain group) and 26 healthy and pain free subjects (reference group) performed a standardized computer office-work task with use of a computer-mouse and with time pressure and high precision demands continuously for 90 min. The pressure pain threshold was measured with a pressure algometer in shoulder and forearm muscles (bilaterally in upper trapezius and extensor carpi radialis), and at sternum, before and 15 min and 30 min after the computer work task. Results The PPTs before starting the computer work were not different between the groups at any of the five locations. In both groups, the PPTs in the active and inactive side of the upper trapezius as well as in the extensor carpi radialis of the forearm operating the computer mouse were significantly reduced after the 90 min computer work compared with the pre-work levels. In the pain group, also the PPT in the inactive resting forearm was significantly reduced. The changes seen in PPTs from pre-to post-work were not significantly different between the groups, except for the inactive resting forearm where the groups exhibited different time course. Conclusion A decrease in pressure pain thresholds of involved muscles suggests that computer office-work can induce deep tissue hyperalgesia within 90 min. The development of pain during the computer work indicates peripheral sensitization as the predominant mechanism. Decreased pressure pain thresholds also in sites distant from pain areas may indicate a contribution from central sensitization in the subjects with chronic shoulder and neck pain. Implications The lasting pain after work and the reduced PPTs both in involved and distant musculature may indicate need for frequent pauses during computer work, especially when performed with time pressure and high precision demands, in order to avoid pain to increase and sustain after work, and thus to prevent the possibility of pain to become chronic.