Sub-arcsecond high sensitivity measurements of the DG~Tau jet with e-MERLIN

We present very high spatial resolution deep radio continuum observations at 5 GHz (6 cm) made with e-MERLIN of the young stars DG Tau A and B. Assuming it is launched very close (~=1 au) from the star, our results suggest that the DG Tau A outflow initially starts as a poorly focused wind and undergoes significant collimation further along the jet (~=50 au). We derive jet parameters for DG Tau A and find an initial jet opening angle of 86 degrees within 2 au of the source, a mass-loss rate of 1.5x10^-8 solar masses/yr for the ionised component of the jet, and the total ejection/accretion ratio to range from 0.06-0.3. These results are in line with predictions from MHD jet-launching theories.Comment: Accepted MNRAS Letter

Effectiveness and reporting standards of psychological interventions for improving short-term and long-term pain outcomes after total knee replacement:a systematic review

Objectives: To assess the effectiveness and reporting standards of psychological interventions for improving outcomes after total knee replacement (TKR).Design: The systematic review protocol was registered on the International Prospective Register of Systematic reviews (CRD42018095100). MEDLINE, EMBASE, and PsycINFO were searched from inception to up to 9th May 2019 with no language restrictions applied. Randomised controlled trials (RCTs) assessing the effectiveness of psychological interventions for short and long-term post-operative pain after TKR were included. Screening, data extraction and assessment of methodological quality was performed in duplicate by two reviewers. The primary effectiveness outcome was post-operative pain severity and the primary harm outcome was serious adverse events. Secondary outcomes included function, quality of life, and psychological wellbeing. Reporting standards were assessed using the TIDieR checklist for intervention reporting. Results: 12 RCTs were included, with a total of 1299 participants. Psychological interventions comprised music therapy (five studies), guided imagery and music (one study), hypnosis (one study) progressive muscle relaxation with biofeedback (one study), pain coping skills programme (one study), cognitive behavioural therapy (two studies), and a post-operative management programme (one study). Due to the high heterogeneity of interventions and poor reporting of harms data, it was not possible to make any definitive statements about the overall effectiveness or safety of psychology interventions for pain outcomes after TKR. Conclusion: Further evidence about the effectiveness of psychological interventions for improving pain outcomes after TKR is needed. The reporting of harm outcomes and intervention fidelity is currently poor and could be improved. Future work exploring the impact of intervention timing on effectiveness and whether different psychological approaches are needed to address acute post-operative pain and chronic post-operative pain would be of benefit

The effectiveness of non-pharmacological sleep interventions for people with chronic pain:a systematic review and meta-analysis

OBJECTIVE: About two thirds of people with chronic pain report problems sleeping. We aimed to evaluate the effectiveness of non-pharmacological sleep interventions for improving sleep in people with chronic pain. DESIGN: We conducted a systematic review of non-pharmacological and non-invasive interventions to improve sleep quality or duration for adults with chronic non-cancer pain evaluated in a randomised controlled trial. Our primary outcome of interest was sleep; secondary outcomes included pain, health-related quality of life, and psychological wellbeing. We searched the Cochrane Library, MEDLINE, Embase, PsycINFO and CINAHL from inception to April 2020. After screening, two reviewers evaluated articles and extracted data. Meta-analysis was conducted using a random effects model. Risk of bias was assessed with the Cochrane tool. RESULTS: We included 42 trials involving 3346 people randomised to 94 groups, of which 56 received an intervention targeting sleep. 10 studies were of fair and 32 of good methodological quality. Overall risk of bias was judged to be low in 11, high in 10 and unclear in 21 studies. In 9 studies with 385 people randomised, cognitive behavioural therapy for insomnia showed benefit post-treatment compared with controls for improved sleep quality, standardised mean difference − 1.23 (95%CI -1.76, − 0.70; p < 0.00001). The effect size was only slightly reduced in meta-analysis of 3 studies at low risk of bias. The difference between groups was lower at 3 and 6 months after treatment but still favoured cognitive behavioural therapy for insomnia. Pain, anxiety and depression were reduced post-treatment, but evidence of longer term benefit was lacking. There was no evidence that sleep hygiene interventions were effective in improving sleep and there was some evidence in comparative studies to suggest that cognitive behavioural therapy for insomnia was more effective than sleep hygiene. Numerous other interventions were evaluated in small numbers of studies, but evidence was insufficient to draw conclusions about effectiveness. CONCLUSIONS: Cognitive behavioural therapy for insomnia is an effective treatment to improve sleep for people with chronic pain, but further high-quality primary research is required to explore combined CBT content that will ensure additional improvements to pain, quality of life and psychological health and longer-term maintenance of benefits. Primary research is also needed to evaluate the effectiveness of interventions for which insufficient evidence exists. TRIAL REGISTRATION: PROSPERO registration number: CRD42019093799. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12891-022-05318-5

Post-operative patient-related risk factors for chronic pain after total knee replacement:a systematic review

ObjectiveTo identify postoperative patient-related risk factors for chronic pain after total knee replacement (TKR).DesignThe systematic review protocol was registered on the International Prospective Register of Systematic Reviews (CRD42016041374). MEDLINE, Embase and PsycINFO were searched from inception to October 2016 with no language restrictions. Key articles were also tracked in the Institute for Scientific Information (ISI) Web of Science. Cohort studies evaluating the association between patient-related factors in the first 3 months postoperatively and pain at 6 months or longer after primary TKR surgery were included. Screening, data extraction and assessment of methodological quality were undertaken by two reviewers. The primary outcome was pain severity in the replaced knee measured with a patient-reported outcome measure at 6 months or longer after TKR. Secondary outcomes included adverse events and other aspects of pain recommended by the core outcome set for chronic pain after TKR.ResultsAfter removal of duplicates, 16 430 articles were screened, of which 805 were considered potentially relevant. After detailed evaluation of full-text articles, 14 studies with data from 1168 participants were included. Postoperative patient-related factors included acute pain (eight studies), function (five studies) and psychosocial factors (four studies). The included studies had diverse methods for assessment of potential risk factors and outcomes, and therefore narrative synthesis was conducted. For all postoperative factors, there was insufficient evidence to draw firm conclusions about the association with chronic pain after TKR. Selection bias was a potential risk for all studies, as none were reported to be conducted at multiple centres.ConclusionThis systematic review found insufficient evidence to draw firm conclusions about the association between any postoperative patient-related factors and chronic pain after TKR. Further high-quality research is required to provide a robust evidence base on postoperative risk factors, and inform the development and evaluation of targeted interventions to optimise patients’ outcomes after TKR.</jats:sec

Effectiveness of postdischarge intervention for reducing the severity of chronic pain after total knee replacement:systematic review of randomised controlled trials

ObjectiveApproximately 20% of patients experience chronic pain after total knee replacement (TKR). The aim of this systematic review was to evaluate the effectiveness of postdischarge interventions commenced in the first 3 months after surgery in reducing the severity of chronic pain after TKR.DesignThe protocol for this systematic review was registered on PROSPERO (registration number: CRD42017041382). MEDLINE, Embase, CINAHL, PsycINFO and The Cochrane Library were searched from inception to November 2016. Randomised controlled trials of postdischarge intervention which commenced in the first 3 months after TKR surgery were included. The primary outcome of the review was self-reported pain severity at 12 months or longer after TKR. Risk of bias was assessed using the Cochrane risk-of-bias tool.ResultsSeventeen trials with data from 2485 randomised participants were included. The majority of trials evaluated physiotherapy interventions (n=13); other interventions included nurse-led interventions (n=2), neuromuscular electrical stimulation (n=1) and a multidisciplinary intervention (n=1). Opportunities for meta-analysis were limited by heterogeneity. No study found a difference in long-term pain severity between trial arms, with the exception of one trial which found home-based functional exercises aimed at managing kinesiophobia resulted in lower pain severity scores at 12 months postoperatively compared with advice to stay active.ConclusionThis systematic review and narrative synthesis found no evidence that one type of physiotherapy intervention is more effective than another at reducing the severity of chronic pain after TKR. Further research is needed to evaluate non-physiotherapy interventions, including the provision of care as part of a stratified and multidisciplinary care package.PROSPERO registration numberCRD42017041382.</jats:sec

Rest Pain and Movement-Evoked Pain as Unique Constructs in Hip and Knee Replacements

OBJECTIVE: There is limited information about the extent to which the association between preoperative and chronic postoperative pain is mediated via pain‐on‐movement or pain‐at‐rest. We explored these associations in patients undergoing total hip replacement (THR) and total knee replacement (TKR). METHODS: A total of 322 and 316 patients receiving THR and TKR, respectively, were recruited into a single‐center UK cohort (Arthroplasty Pain Experience) study. Preoperative, acute postoperative, and 12‐month pain severity was measured using self‐reported pain instruments. The association between preoperative/acute pain and chronic postoperative pain was investigated using structural equation modeling (SEM). RESULTS: Patients with high levels of preoperative pain were more likely to report chronic pain after THR (β = 0.195, P = 0.02) and TKR (β = 0.749, P < 0.0001). Acute postoperative pain‐on‐movement was not associated with chronic pain after TKR or THR after adjusting for preoperative pain; however, acute pain‐at‐rest was associated with chronic pain after THR (β = 0.20, P < 0.0002) but not TKR after adjusting for preoperative pain. Analysis of pain‐at‐rest and pain‐on‐movement highlighted differences between THR and TKR patients. Chronic pain‐at‐rest after THR was weakly associated with pain‐at‐rest during the preoperative (β = 0.11, P = 0.068) and acute postoperative period (β = 0.21, P < 0.0001). In contrast, chronic pain‐on‐movement after TKR was strongly associated with the severity of pain‐on‐movement during the preoperative period (β = 0.51, P = 0.001). CONCLUSION: SEM illustrated the different patterns of association between measures of pain over time in patients undergoing THR and TKR for osteoarthritis. These findings highlight the importance of future work that explores the mechanisms underlying pain‐on‐movement and pain‐at‐rest

Trajectories of Pain and Function after Primary Hip and Knee Arthroplasty:The ADAPT Cohort Study

BACKGROUND AND PURPOSE:Pain and function improve dramatically in the first three months after hip and knee arthroplasty but the trajectory after three months is less well described. It is also unclear how pre-operative pain and function influence short- and long-term recovery. We explored the trajectory of change in function and pain until and beyond 3-months post-operatively and the influence of pre-operative self-reported symptoms. METHODS:The study was a prospective cohort study of 164 patients undergoing primary hip (n = 80) or knee (n = 84) arthroplasty in the United Kingdom. Self-reported measures of pain and function using the Western Ontario and McMaster Universities Osteoarthritis index were collected pre-operatively and at 3 and 12 months post-operatively. Hip and knee arthroplasties were analysed separately, and patients were split into two groups: those with high or low symptoms pre-operatively. Multilevel regression models were used for each outcome (pain and function), and the trajectories of change were charted (0-3 months and 3-12 months). RESULTS:Hip: Most improvement occurred within the first 3 months following hip surgery and patients with worse pre-operative scores had greater changes. The mean changes observed between 3 and twelve months were statistically insignificant. One year after surgery, patients with worse pre-operative scores had post-operative outcomes similar to those observed among patients with less severe pre-operative symptoms. Knee: Most improvement occurred in the first 3 months following knee surgery with no significant change thereafter. Despite greater mean change during the first three months, patients with worse pre-operative scores had not 'caught-up' with those with less severe pre-operative symptoms 12 months after their surgery. CONCLUSION:Most symptomatic improvement occurred within the first 3 months after surgery with no significant change between 3-12 months. Further investigations are now required to determine if patients with severe symptoms at the time of their knee arthroplasty have a different pre-surgical history than those with less severe symptoms and if they could benefit from earlier surgical intervention and tailored rehabilitation to achieve better post-operative patient-reported outcomes