3D MRI Modeling of Thin and Spatially Complex Soft Tissue Structures without Shrinkage: Lamprey Myosepta as an Example.

3D imaging techniques enable the nondestructive analysis and modeling of complex structures. Among these, MRI exhibits good soft tissue contrast, but is currently less commonly used for nonclinical research than X-ray CT, even though the latter requires contrast-staining that shrinks and distorts soft tissues. When the objective is the creation of a realistic and complete 3D model of soft tissue structures, MRI data are more demanding to acquire and visualize and require extensive post-processing because they comprise noncubic voxels with dimensions that represent a trade-off between tissue contrast and image resolution. Therefore, thin soft tissue structures with complex spatial configurations are not always visible in a single MRI dataset, so that standard segmentation techniques are not sufficient for their complete visualization. By using the example of the thin and spatially complex connective tissue myosepta in lampreys, we developed a workflow protocol for the selection of the appropriate parameters for the acquisition of MRI data and for the visualization and 3D modeling of soft tissue structures. This protocol includes a novel recursive segmentation technique for supplementing missing data in one dataset with data from another dataset to produce realistic and complete 3D models. Such 3D models are needed for the modeling of dynamic processes, such as the biomechanics of fish locomotion. However, our methodology is applicable to the visualization of any thin soft tissue structures with complex spatial configurations, such as fasciae, aponeuroses, and small blood vessels and nerves, for clinical research and the further exploration of tensegrity. Anat Rec, 301:1745-1763, 2018. © 2018 Wiley Periodicals, Inc.

The Relationship Between Pacing and Avoidance in Chronic Pain: A Systematic Review and Meta-Analysis.

Activity pacing is ubiquitous in chronic pain management and aims to reduce pain-contingent avoidance of activity to improve functioning. A meta-analysis, however, has linked pacing with higher levels of pain and disability. One potential explanation is an overlap between existing measures of pacing and avoidance, leading to links with poorer outcomes that are typically associated with avoidance. This study systematically reviews the evidence regarding the relationship between measures of pacing and avoidance. A search was conducted for studies measuring both constructs in adults with chronic pain. A meta-analysis of correlations between pacing and avoidance was conducted; 16 studies were included and a small positive correlation was found (r = .290, P < .001) overall. Single-item and multiple-item measures were also compared; a moderate positive correlation was found for multiple-item measures (r = .410, P < .001), which differed significantly from a small positive correlation found for single-item measures (r = .105, P < .001). Due to limited studies, independent analyses of individual subscales were not possible. Existing measures of pacing-particularly multiple-item measures-may partially confound pacing with avoidance. Further research is required to ensure that a reliable measure of pacing that distinguishes this construct from avoidance is available to adequately evaluate pacing instruction and the effect of pacing on key outcomes in chronic pain. PERSPECTIVE: This meta-analysis examines the correlation between pacing and avoidance in adults with chronic pain. Results indicate that existing measures may partially confound pacing with avoidance. Directions for future research are proposed to ensure that an adequate measure of pacing exists to evaluate its effect on key outcomes in chronic pain.

Long-term outcomes from training in self-management of chronic pain in an elderly population: a randomized controlled trial.

This study compares the outcomes, from pretreatment to 1-year follow-up, of an outpatient, CBT-based pain self-management program (PSM) that included exercises, pain education, and pain coping strategies, with a control condition (exercise-attention control, EAC) that included exercises and a control for the attention of the treatment team. We previously reported short-term results (to 1-month follow-up) from the same study. This new paper considers the important issue of maintenance of treatment-related gains. The participants (n = 141) were a heterogeneous sample of ambulant, community-dwelling older adult patients with chronic pain (mean age: 73.90 [6.5] years [range: 65-87 years]). The long-term results indicate the pain self-management program group achieved and maintained significantly better results than the exercise-attention control group on the primary outcome, pain-related disability, as well as on usual pain, pain distress, depression, and fear-avoidance beliefs. The mean effect size for these gains by the pain self-management program group over the exercise-attention control group was 0.37 (range: 0.29-0.45), which is in the small effect size range. While statistically and clinically meaningful, these findings do indicate some weakening in effects over time but not to a significant degree. The study has implications for the provision of pain management interventions for community-dwelling older adults with chronic pain.

The mediating role of catastrophizing in the relationship between pain intensity and depressed mood in older adults with persistent pain: A longitudinal analysis.

BACKGROUND AND AIMS: Depression is common in older adults with persistent pain. Cognitive-behavioural models of pain propose that the relationship between pain and depression is influenced or mediated by interpretations of events (cognitions), rather than by the event itself. Almost exclusively, the evidence for this position has come from studies of people aged less than 65 years. The role of cognitions in the pain experience of older adults has been unclear due to the limited and conflicting evidence available. The aim of our study was to examine the role of catastrophizing in mediating the relationship between pain intensity and depressed mood in older adults with persistent pain using reliable and valid measures for this population. METHODS: In a two-wave longitudinal design, a sample of 141 patients (89 women, 52 men) 65 years and over with persistent pain participating in an evaluation of a pain self-management programme completed questionnaires measuring usual level of pain intensity (NRS), depressed mood (DASS-21) and the catastrophizing factors of magnification and helplessness (PRSS) at the beginning of the programme and 6 months later. Demographic data and pain history were collected by self-completion questionnaires, which were mailed to patients prior to participating in the programme and returned by post. RESULTS: Change scores for usual level of pain intensity (NRS), depressed mood (DASS-21) and the magnification and helplessness factors on the PRSS-Catastrophizing were calculated by subtracting the scores at 6 months after completion of the study (Time 2) from the scores at the beginning of the study (Time 1). In the longitudinal analyses of mediation, using a series of regression analyses, change scores for both factors (magnification, helplessness) of the measure of catastrophizing (PRSS) totally and significantly mediated the relationship between change scores for pain intensity and depressed mood. The significant relative magnitude of beta between pain intensity and depression reduced from 0.22 to 0.13 and became non-significant after introducing magnification as a mediating variable, whilst the significant relative magnitude of beta reduced from 0.22 to 0.12 and also became non-significant after introducing helplessness as a mediating variable. CONCLUSIONS: These results support a cognitive-behavioural model and highlight the importance of cognitive factors, in this case catastrophizing, in the relationship between pain intensity and depressed mood in older adults with persistent pain. IMPLICATIONS: These findings also have important clinical implications for the treatment of older adults with persistent pain. They highlight the importance of targeting interventions to reduce the influence of catastrophizing as a prerequisite for reducing depressive symptoms in this growing population.

The effectiveness of psychological treatments for chronic pain in older adults: cautious optimism and an agenda for research.

PURPOSE OF REVIEW: To explores the potential role of psychological treatments for older people who are affected by chronic pain. RECENT FINDINGS: It is now widely recognized that chronic pain is a highly prevalent health problem among older people, and guidelines have evolved to assist with the assessment and management of chronic pain. However, despite the fact that psychological treatments have been shown to be effective for a range of other conditions such as depression and anxiety, there is a relative paucity of studies focused on pain management. Although more evidence is needed, the trend from existing studies indicates that older people find psychological treatments for chronic pain to be relevant, acceptable in content, and beneficial in reducing distress and disability. Particular challenges arise for the delivery of psychological interventions to people with pain and cognitive impairment associated with dementia. There is a growing interest in this population and a good deal of research has focused on the assessment of pain, but with a small number of exceptions, almost no research activity as yet in developing psychological treatments for people with pain and dementia. SUMMARY: We conclude that there is sufficient evidence that psychological interventions are efficacious for older people with chronic pain. We propose a number of areas for research focus over the next 10 years that will help to consolidate our knowledge and to explore new avenues for the psychological management of chronic pain in older people.

Self-management intervention for chronic pain in older adults: a randomised controlled trial.

This study compared an outpatient pain self-management (PSM) program, using cognitive-behavioural therapy and exercises, with 2 control conditions in 141 chronic pain patients aged > 65 years. Results immediately posttreatment indicated that relative to the Exercise-Attention Control (EAC) group, the PSM group was significantly improved on measures of pain distress, disability, mood, unhelpful pain beliefs, and functional reach. The mean effect size for these gains was 0.52 (range: 0.44-0.68). By 1-month follow-up, relative to the EAC group, the PSM group remained better on most measures. At the 1-month follow-up, relative to a Waiting List (usual care) (WL) group, the PSM group was significantly improved on measures of pain distress, disability, and unhelpful pain beliefs. The mean effect size for these variables was 0.69 (range: 0.56-0.83). Relative to the WL group, the EAC group made no significant gains on any of the measured variables. At 1-month follow-up, the mean proportion of reliably improved cases (across outcome variables) was 41% (range: 16-60%) for the PSM group, twice that of those who met this criterion in the 2 control conditions (and this difference was statistically significant). Similarly, significantly more (44%) of the PSM group (vs 22% and 20% for the control groups) achieved a clinically significant improvement on pain disability. In the short term at least, cognitive-behavioural therapy-based PSM was more effective than exercises and usual care.

Catastrophizing mediates the relationship between pain intensity and depressed mood in older adults with persistent pain.

UNLABELLED: This study examined the role of catastrophizing in mediating the relationship between pain intensity and depressed mood in older adults with persistent pain using reliable and valid measures for this population. A convenience sample of 669 patients 61 years and over attending a tertiary-level referral pain center completed questionnaires measuring pain intensity, depressed mood, and catastrophizing as part of a clinical assessment process. The catastrophizing subscale of the Pain-Related Self-Statements scale (PRSS-Catastrophizing) was examined for internal consistency and factor structure. Mediation was tested for each factor from the optimal model of the PRSS-Catastrophizing scale using regression analyses, which included measures of pain intensity and depressed mood. The PRSS-Catastrophizing scale was found to be a reliable measure of pain-related catastrophizing. A 2-factor solution (magnification, helplessness) was identified. Both factors partially and significantly mediated the relationship between pain intensity and depressed mood. This study highlights the importance of cognitive factors-in this case catastrophizing-in the persistent pain experience of older adults. It also demonstrates that pain-related catastrophizing can be reliably measured in this population. These findings have important clinical implications. They emphasize the importance of using interventions to reduce catastrophizing to modify the pain experience of older adults with persistent pain. PERSPECTIVE: This study confirms the mediating role of catastrophizing in the relationship between pain intensity and depressed mood in older adults with persistent pain using psychometrically sound measures. These findings indicate that clinicians should address catastrophizing to improve treatment outcomes with this population.

The utility of the short version of the Depression Anxiety Stress Scales (DASS-21) in elderly patients with persistent pain: does age make a difference?

OBJECTIVE: This study examined the assessment of the negative emotional constructs of depression, anxiety and stress with the short version (21 items) of the Depression Anxiety Stress Scales (DASS-21) in elderly patients (age > 60 years) with persistent pain. DESIGN: A convenience sample of 2,045 patients attending a tertiary referral pain centre were categorized by age and included a group aged 60 years and under (n=1,245) for assessment of age differences. Elderly patients (n=800) were divided into 3 groups: 61-70 years (n=366), 71-80 years (n=308) and 81 years and over (n=126). Patients completed the DASS-21 as part of an initial clinical assessment process. RESULTS: The failure rate for scale completion increased across age groups and was significantly higher in the oldest group compared to the youngest group. All scales demonstrated reasonable convergent and divergent validity. Confirmatory factor analysis confirmed a three-factor structure and is consistent with previous studies. Age differences in depression, anxiety and stress scores were also assessed. Interestingly, patients aged 60 years and under had significantly higher Depression and Stress scores compared to all other age groups. This group also had significantly higher Anxiety scores compared to patients aged 61-70 years. CONCLUSIONS: Overall, the DASS-21 is a reliable and valid measure of depression, anxiety and stress in elderly patients with persistent pain. There are some age differences in the normative values for the reporting of mood symptoms and these need to be taken into account when assessing pain-related mood disturbance in older populations.

Assessing pain in older people with persistent pain: the NRS is valid but only provides part of the picture.

UNLABELLED: This study examined the assessment of pain intensity and pain distress with the Numerical Rating Scale (NRS) in elderly patients (age > 60 years) with persistent pain. A consecutive sample of 800 elderly patients were categorized by age into 3 groups: 61 to 70 years (n = 366), 71 to 80 years (n = 308), and 81 years and over (n = 126). Participants completed 3 Numerical Rating Scales assessing current pain intensity, and both the usual level of pain and average pain distress in the preceding week. The failure rate for scale completion was low for all scales for all age groups, but was significantly higher in the oldest group compared to the youngest group for the scales assessing current pain intensity and average pain distress in the preceding week. The NRS was shown to be a reliable and valid measure of pain intensity and pain distress in all these age groups. Distress related to pain appeared to be specific to the pain experience and was only weakly related to more generalized affective distress. These findings confirm that measures of pain intensity and pain distress, like the NRS, capture only part of the pain experience in older patients and should be supplemented by other measures in the assessment process. PERSPECTIVE: This article confirms the utility of the Numerical Rating Scale (NRS) as a measure of pain intensity and pain distress in elderly patients with persistent pain. The use of a large sample increases confidence in the psychometric soundness of the NRS with this population.