Determining appropriate measurement methods for etiological research of computing-related musculoskeletal symptoms and disorders

Two studies among college students were conducted to evaluate appropriate measurement methods for etiological research on computing-related upper extremity musculoskeletal disorders (UEMSDs). ^ A cross-sectional study among 100 graduate students evaluated the utility of symptoms surveys (a VAS scale and 5-point Likert scale) compared with two UEMSD clinical classification systems (Gerr and Moore protocols). The two symptom measures were highly concordant (Lin's rho = 0.54; Spearman's r = 0.72); the two clinical protocols were moderately concordant (Cohen's kappa = 0.50). Sensitivity and specificity, endorsed by Youden's J statistic, did not reveal much agreement between the symptoms surveys and clinical examinations. It cannot be concluded self-report symptoms surveys can be used as surrogate for clinical examinations. ^ A pilot repeated measures study conducted among 30 undergraduate students evaluated computing exposure measurement methods. Key findings are: temporal variations in symptoms, the odds of experiencing symptoms increased with every hour of computer use (adjOR = 1.1, p < .10) and every stretch break taken (adjOR = 1.3, p < .10). When measuring posture using the Computer Use Checklist, a positive association with symptoms was observed (adjOR = 1.3, p < 0.10), while measuring posture using a modified Rapid Upper Limb Assessment produced unexpected and inconsistent associations. The findings were inconclusive in identifying an appropriate posture assessment or superior conceptualization of computer use exposure. ^ A cross-sectional study of 166 graduate students evaluated the comparability of graduate students to College Computing & Health surveys administered to undergraduate students. Fifty-five percent reported computing-related pain and functional limitations. Years of computer use in graduate school and number of years in school where weekly computer use was ≥ 10 hours were associated with pain within an hour of computing in logistic regression analyses. The findings are consistent with current literature on both undergraduate and graduate students. ^

Chronic spontaneous activity generated in the somata of primary nociceptors is associated with pain-related behavior after spinal cord injury.

Mechanisms underlying chronic pain that develops after spinal cord injury (SCI) are incompletely understood. Most research on SCI pain mechanisms has focused on neuronal alterations within pain pathways at spinal and supraspinal levels associated with inflammation and glial activation. These events might also impact central processes of primary sensory neurons, triggering in nociceptors a hyperexcitable state and spontaneous activity (SA) that drive behavioral hypersensitivity and pain. SCI can sensitize peripheral fibers of nociceptors and promote peripheral SA, but whether these effects are driven by extrinsic alterations in surrounding tissue or are intrinsic to the nociceptor, and whether similar SA occurs in nociceptors in vivo are unknown. We show that small DRG neurons from rats (Rattus norvegicus) receiving thoracic spinal injury 3 d to 8 months earlier and recorded 1 d after dissociation exhibit an elevated incidence of SA coupled with soma hyperexcitability compared with untreated and sham-treated groups. SA incidence was greatest in lumbar DRG neurons (57%) and least in cervical neurons (28%), and failed to decline over 8 months. Many sampled SA neurons were capsaicin sensitive and/or bound the nociceptive marker, isolectin B4. This intrinsic SA state was correlated with increased behavioral responsiveness to mechanical and thermal stimulation of sites below and above the injury level. Recordings from C- and Aδ-fibers revealed SCI-induced SA generated in or near the somata of the neurons in vivo. SCI promotes the entry of primary nociceptors into a chronic hyperexcitable-SA state that may provide a useful therapeutic target in some forms of persistent pain.

Factors influencing participation in individuals with disability: A secondary data analysis

Individuals with disabilities face numerous barriers to participation due to biological and physical characteristics of the disability as well as social and environmental factors. Participation can be impacted on all levels from societal, to activities of daily living, exercise, education, and interpersonal relationships. This study evaluated the impact of pain, mood, depression, quality of life and fatigue on participation for individuals with mobility impairments. This cross sectional study derives from self-report data collected from a wheelchair using sample. Bivariate correlational and multivariate analysis were employed to examine the relationship between pain, quality of life, positive and negative mood, fatigue, and depression with participation while controlling for relevant socio-demographic variables (sex, age, time with disability, race, and education). Results from the 122 respondents with mobility impairments demonstrated that after controlling for socio-demographic characteristics in the full model, 20% of the variance in participation scores were accounted for by pain, quality of life, positive and negative mood, and depression. Notably, quality of life emerged as being the single variable that was significantly related to participation in the full model. Contrary to other studies, pain did not appear to significantly impact participation outcomes for wheelchair users in this sample. Participation is an emerging area of interest among rehabilitation and disability researchers, and results of this study provide compelling evidence that several psychosocial factors are related to participation. This area of inquiry warrants further study, as many of the psychosocial variables identified in this study (mood, depression, quality of life) may be amenable to intervention, which may also positively influence participation.^

Heart rate variability in response to pain stimulus in VLBW infants followed longitudinally during NICU stay.

The objective of this longitudinal study, conducted in a neonatal intensive care unit, was to characterize the response to pain of high-risk very low birth weight infants (<1,500 g) from 23 to 38 weeks post-menstrual age (PMA) by measuring heart rate variability (HRV). Heart period data were recorded before, during, and after a heel lanced or wrist venipunctured blood draw for routine clinical evaluation. Pain response to the blood draw procedure and age-related changes of HRV in low-frequency and high-frequency bands were modeled with linear mixed-effects models. HRV in both bands decreased during pain, followed by a recovery to near-baseline levels. Venipuncture and mechanical ventilation were factors that attenuated the HRV response to pain. HRV at the baseline increased with post-menstrual age but the growth rate of high-frequency power was reduced in mechanically ventilated infants. There was some evidence that low-frequency HRV response to pain improved with advancing PMA.

Molluscan memory of injury: evolutionary insights into chronic pain and neurological disorders.

Molluscan preparations have yielded seminal discoveries in neuroscience, but the experimental advantages of this group have not, until now, been complemented by adequate molecular or genomic information for comparisons to genetically defined model organisms in other phyla. The recent sequencing of the transcriptome and genome of Aplysia californica, however, will enable extensive comparative studies at the molecular level. Among other benefits, this will bring the power of individually identifiable and manipulable neurons to bear upon questions of cellular function for evolutionarily conserved genes associated with clinically important neural dysfunction. Because of the slower rate of gene evolution in this molluscan lineage, more homologs of genes associated with human disease are present in Aplysia than in leading model organisms from Arthropoda (Drosophila) or Nematoda (Caenorhabditis elegans). Research has hardly begun in molluscs on the cellular functions of gene products that in humans are associated with neurological diseases. On the other hand, much is known about molecular and cellular mechanisms of long-term neuronal plasticity. Persistent nociceptive sensitization of nociceptors in Aplysia displays many functional similarities to alterations in mammalian nociceptors associated with the clinical problem of chronic pain. Moreover, in Aplysia and mammals the same cell signaling pathways trigger persistent enhancement of excitability and synaptic transmission following noxious stimulation, and these highly conserved pathways are also used to induce memory traces in neural circuits of diverse species. This functional and molecular overlap in distantly related lineages and neuronal types supports the proposal that fundamental plasticity mechanisms important for memory, chronic pain, and other lasting alterations evolved from adaptive responses to peripheral injury in the earliest neurons. Molluscan preparations should become increasingly useful for comparative studies across phyla that can provide insight into cellular functions of clinically important genes.

Comparison of cost and outcome of care in patients with low back pain who are managed by physicians or physical therapists in private practice

The purpose of this study was to determine if there were differences in the cost and outcome of care in patients with low back pain who were managed by physicians or physical therapists in private practice in the state of Arizona. A secondary purpose was to describe the current status of private practice physical therapy clinicians who treat patients with low back pain.^ A Survey on Practice was mailed to 194 physical therapists who were listed by the American Physical Therapy Association as being in private practice in Arizona. Eighty-three percent of the surveys were returned after three attempts. Of those which were returned, 72 were complete and included in the analysis.^ The 72 practices were screened to determine those eligible for the second phase of the study. Those eligible for the second phase numbered 52 clinics. Twenty-six practices agreed to participate; however, only 21 did participate. Clinics which participated were sent packets of information which were to be kept on each patient seen with a complaint of low back pain during a three month period. Packets contained a patient-oriented survey on functional activity to be completed before and after the physical therapy course of treatment, as well as a log which was completed by the physical therapist on the type of care given to the patient and an assessment of the outcome of treatment. The patient was asked to fill out a satisfaction survey relative to the care received from the physical therapist and physician, if applicable.^ Although 259 patients were entered into the study, 210 patient logs were available for analysis. Results indicated that generally, there was no difference in cost or outcome as measured by the final functional score, change between the initial and final functional scores, or the therapist-rated outcome between the patients who were managed by physicians or physical therapists when controlling for age and length of time the patient was experiencing pain. Patients were more satisfied with care received from physical therapists as compared to physicians. Age and length of pain were good predictors of the type of referral patients received according to a logistic regression procedure. The initial disability score (IRS) and the time spent in the facility predicted therapist-rated outcome, a good or poor final disability score (FRS), and a good or poor change score. In addition, age predicted FRS and change scores. The time that the therapist spent in direct contact with the patient also predicted the change score.^ These findings of no difference in the cost and outcome of care were discussed as they relate to the practice of medicine and physical therapy. ^

Back pain in migrant farmworker families and farmworker high school students from Starr County, Texas

Back symptoms are a major global public health problem with the lifetime prevalence ranging between 50-80%. Research suggests that work-related factors contribute to the occurrence of back pain in various industries. Despite the hazardous nature, strenuous tasks, and awkward postures associated with farm work, little is known about back injury and symptoms in farmworker adults and children. Research in the United States is particularly limited. This is a concern given the large proportion of migrant farmworkers in the United States without adequate access to healthcare as well as a substantial number of youth working in agriculture. The present study describes back symptoms and identifies work-related factors associated with back pain in migrant farmworker families and farmworker high school students from Starr County, TX. Two separate datasets were used from two cohort studies "Injury and Illness Surveillance in Migrant Farmworkers (MANOS)" (study A: n=267 families) and "South Texas Adolescent Rural Research Study (STARRS)" (study B: n=345). Descriptive and inferential statistics including multivariable logistic regression were used to identify work-related factors associated with back pain in each study. In migrant farmworker families, the prevalence of chronic back pain during the last migration season ranged from 9.5% among youngest children to 33.3% among mothers. Chronic back pain was significantly associated with increasing age; fairly bad/very bad quality of sleep while migrating; fewer than eight hours of sleep at home in Starr County, TX; depressive symptoms while migrating; self-provided water for washing hands/drinking; weeding at work; and exposure to pesticide drift/direct spray. Among farmworker adolescents, the prevalence of severe back symptoms was 15.7%. Severe back symptoms were significantly associated with being female; history of a prior accident/back injury; feeling tense, stressed, or anxious sometimes/often; lifting/carrying heavy objects not at work; current tobacco use; increasing lifetime number of migrant farmworker years; working with/around knives; and working on corn crops. Overall, results support that associations between work-related exposures and chronic back pain and severe back symptoms remain after controlling for the effect of non-work exposures in farmworker populations. ^

Blood-oxygen-level-dependent (BOLD) signal changes in total cortex and subcortex, pain, reward, and vigilance regions during mechanical pressure pain after morphine administration

Morphine is the most common clinical choice in the management of severe pain. Although the molecular mechanisms of morphine have already been characterized, the cerebral circuits by which it attenuates the sensation of pain have not yet been studied in humans. The objective of this two-arm (morphine versus placebo), between-subjects study was to examine whether morphine affects pain via pain-related cortical circuits, but also via reward regions that relate to the motivational state, as well as prefrontal regions that relate to vigilance as a result of morphine's sedative effects. Cortical activity was measured by the blood-oxygen-level-dependent (BOLD) signal changes using functional magnetic resonance imaging (fMRI). ^ The novelty of this study is at three levels: (i) to develop a methodology that will assess the average BOLD signal across subjects for the pain, reward, and vigilance cortical systems; (ii) to examine whether the reward and/or sedative effects of morphine are contributing factors to cortical regions associated with the motivational state and vigilance; and (iii) to propose a neuroanatomical model related to the opioid-sensitive effects of reward and sedation as a function of cortical activity related to pain in an effort to assess future analgesics. ^ Consistent with our hypotheses, our findings showed that the decrease in total pain-related volume activated between the post- and the pre-treatment morphine group was about 78%, while the post-treatment placebo group displayed only a 5% decrease when compared to pre-treatment levels of activation. The volume increase in reward regions was 451% in the post-treatment compared to the pre-treatment morphine condition. Finally, the volumetric decrease in vigilance regions was 63% in the posttreatment compared to the pre-treatment morphine condition. ^ These findings imply that changes in the blood flow of the reward and vigilance regions may be contributing factors in producing the analgesic effect under morphine administration. Future studies need to replicate this study in a higher resolution fMRI environment and to assess the proposed neuroanatomical model in patient populations. The necessity of pain research is apparent, since pain cuts across different diseases especially chronic ones, and thus, is recognized as a vital public health developing area. ^

The impact of antibiotic associated diarrhea on health related quality of life in hospitalized patients

Objective. To determine the impact of antibiotic associated diarrhea (AAD) on health related quality of life (HRQOL) in hospitalized patients compared to matched controls without diarrhea. ^ Methods. This is a hospital-based, matched case-control study using secondary data from a prospective cohort trial of patients receiving broad-spectrum antibiotics. One hundred and seventy-eight patients were recruited of whom 18 (10%) reported having antibiotic associated diarrhea. Two non-diarrhea controls were selected for each case with diarrhea giving a final sample of 18 cases and 36 controls. Responses from Short Form (SF) 36 questionnaire were aggregated into eight domains including physical functioning (PF), role-functioning physical (RP), bodily pain (BP), general health (GH), social functioning (SF), vitality (VT), role-functioning emotional (RE), and mental health (MH). The eight domains were compared between cases and controls. A GI targeted HRQOL measure was administered to 13 patients with AAD. Responses from the disease-specific instrument were combined in eight subscale scores: dysphoria, interference with activity, body image, health worry, food avoidance, social reaction, sex, and relationships. ^ Results. The sample consisted of 41 females (75.9%) and 13 males (24.1%) aged 53.5 ± 14.4 years (range: 21-76 years). Twenty five patients (46%) were Caucasian, 15 (27%) were African American, 13(24%) were Hispanic and 1(2%) was Asian. In univariate analysis, no significant differences in quality of life outcomes were observed in each of the SF36 domains between the case patients and matched controls. There were trends for decreased scores on the role-functioning physical, bodily pain, general health, social functioning, mental health, and mental summary domains. In total, 7 of 8 domain scores were lower in patients with AAD and 5 of 8 domain scores were lower by more than 5 points (considered clinically significant). Controlling for age, patients with antibiotic associated diarrhea had significantly lower general health, vitality, and mental health scale scores (p<0.05 each). The disease-specific scores were significantly lower in patients with AAD than those in published norms for irritable bowel syndrome patients. ^ Conclusion. In this small sample, several areas of decreased QOL in patients with AAD compared to matched controls were noted. A larger sample size to validate these results is necessary.^

Frequency, severity and distress of dialysis-related symptoms reported by patients on hemodialysis

Purpose. To determine which symptoms are the most reported, occur most frequently, have the greatest severity, and cause the most bother for hemodialysis (HD) patients and to determine if the symptoms experienced differ between the first (HD 1) and second (HD 2) treatments of the week. ^ Design. An observational, comparative design was used to determine participants' HD symptoms experience on HD 1 and HD 2, and the effect of the symptom experience on Quality of Life (QOL). One hundred subjects were recruited from five dialysis centers. ^ Methods. The adapted Dialysis Frequency, Severity and Symptom Burden Index (DFSSBI) and the Medical Outcomes Study Short Form 36 (MOS SF 36) were administered (N = 99) on HD 1 and the DFSSBI again on HD 2. Data were analyzed for significance among symptoms experience test scores in relation to HD 1 and HD 2, QOL, and gender and age. ^ Results. Of 31 symptoms assessed, respondents reported an average of 9.69 symptoms on HD 1 and 7.51 symptoms on HD 2. Overall, more symptoms were reported, and were more frequent, severe and bothersome on HD 1 when the level of metabolic waste is highest. The most reported symptoms included tiredness, dry skin, difficulty falling asleep, itching, numbness/tingling, difficulty staying asleep, decreased interest in sex, and bone/joint pain. Females scored consistently higher than males in the four symptom dimensions. The respondents reported about the same as the population norm (50) on the physical component summary score of the MOS SF 36 and higher than the norm (65.23) on the mental component summary score. ^ Conclusion. The study findings highlighted the fact that hemodialysis patients experience multiple symptoms that can be frequent, severe, and bothersome. Interventions should be developed and tested to reduce symptom burden and improve QOL. ^

Process to develop a State Model Law to reduce prescription drug trafficking while protecting pain management

This paper will discuss the intersection of pill mills and the under-treatment of pain, while addressing the unintended consequence that cracking down on pill mills actually has on medical professionals' treatment of legitimate pain in clinical settings. Moreover, the impact each issue has on the spectrum of related policy, regulatory issues and legislation will be analyzed while addressing the national impact on medical care. Lastly, this paper will outline a process to develop a State Model Law on this subject. This process will include suggestions for the future and how we can move forward to adequately address public safety needs and how we can attempt to mitigate the unintended impact prescription drug trafficking has had on a patient's right to appropriate pain management. This balance is achievable and this paper will address ways we can find this elusive balancing point through the development of a State Model Law. ^

A methodologic study of pain assessment in Anglo and Hispanic children with cancer

There is growing clinical evidence that even young children experience pain and accompanying anxiety. Few instruments have been validated to assess pain characteristics in children. The study of related demographic, illness, psychologic and parental factors in children has also been limited. This study examines the reliability and validity of pain assessment tools in an outpatient pediatric cancer population. A total of 78 children from three to fifteen years of age were observed and interviewed about the pain of invasive procedures. The effect of cultural factors and the stress of acculturation were examined by comparing data from two cultural groups, Anglo and Hispanic.^ Spielberger State-Trait Anxiety Scales were administered to children and parents prior to an invasive procedure. The Procedure Behavioral Checklist (PBCL) was used for observation of the child's response during the procedure. The Children's Procedural Interview (CPI) which contains items on the PBCL and visual analogues (scales of faces indicating varying degrees of pain and anxiety) was administered following the procedure.^ Reliability coefficients for Anglos were.78 on the PBCL,.79 on the CPI and.85 on the visual analogue scales. For Hispanics, the reliability for the PBCL was.54, while the CPI had a reliability of.72 and the visual analogue scales,.87. Construct validity was demonstrated by high correlations between the PBCL and CPI scores for both ethnic groups (.66 for Anglos and.64 for Hispanics) and by the significant correlation of State anxiety scores with both PBCL and CPI scores. Age was inversely correlated with PBCL and CPI scores for both ethnic groups. Hispanic parents' anxiety scores were higher than Anglo parents, but were not highly correlated with their child's PBCL, CPI or State-Trait anxiety scores. Caregivers' ratings were correlated with the PBCL scores for Anglos but not for Hispanics.^ The findings of this study indicate that pain responses may be reliably assessed using both observational and self-report methods in children, though differences in Anglo and Hispanic cultures exist. Differences in pain symptomatology and assessment in the two cultural groups warrant further study. ^