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

The EQ-5D-3L administered by text message compared to the paper version for hard-to-reach populations in a rural South African trauma setting:a measurement equivalence study

INTRODUCTION: Administering patient-reported outcome measures (PROMs) by text message may improve response rate in hard-to-reach populations. This study explored cultural acceptability of PROMs and compared measurement equivalence of the EQ-5D-3L administered on paper and by text message in a rural South African setting. MATERIALS AND METHODS: Participants with upper or lower limb orthopaedic pathology were recruited. The EQ-5D was administered first on paper and then by text message after 24 h and 7 days. Differences in mean scores for paper and text message versions of the EQ-5D were evaluated. Test–retest reliability between text message versions was evaluated using Intraclass Correlation Coefficients (ICCs). RESULTS: 147 participants completed a paper EQ-5D. Response rates were 67% at 24 h and 58% at 7 days. There were no differences in means between paper and text message responses for the EQ-5D Index (p = 0.95) or EQ-5D VAS (p = 0.26). There was acceptable agreement between the paper and 24-h text message EQ-5D Index (0.84; 95% Confidence Interval (CI) 0.78–0.89) and EQ-5D VAS (0.73; 95% CI 0.64–0.82) and acceptable agreement between the 24-h and 7-day text message EQ-Index (0.72; CI 0.62–0.82) and EQ-VAS (0.72; CI 0.62–0.82). Non-responder traits were increasing age, Xhosa as first language and lower educational levels. CONCLUSIONS: Text messaging is equivalent to paper-based measurement of EQ-5D in this setting and is thus a viable tool for responders. Non-responders had similar socioeconomic characteristics and attrition rates to traditional modes of administration. The EQ-5D by text message offers potential clinical and research uses in hard-to-reach populations

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

Planck pre-launch status: HFI beam expectations from the optical optimisation of the focal plane

Planck is a European Space Agency (ESA) satellite, launched in May 2009, which will map the cosmic microwave background anisotropies in intensity and polarisation with unprecedented detail and sensitivity. It will also provide full-sky maps of astrophysical foregrounds. An accurate knowledge of the telescope beam patterns is an essential element for a correct analysis of the acquired astrophysical data. We present a detailed description of the optical design of the High Frequency Instrument (HFI) together with some of the optical performances measured during the calibration campaigns. We report on the evolution of the knowledge of the pre-launch HFI beam patterns when coupled to ideal telescope elements, and on their significance for the HFI data analysis procedure

Effectiveness and Cost-effectiveness of Outpatient Physiotherapy After Knee Replacement for Osteoarthritis: Study Protocol for a Randomised Controlled Trial

Background: Primary total knee replacement is a common operation that is performed to provide pain relief and restore functional ability. Inpatient physiotherapy is routinely provided after surgery to enhance recovery prior to hospital discharge. However, international variation exists in the provision of outpatient physiotherapy after hospital discharge. While evidence indicates that outpatient physiotherapy can improve short-term function, the longer term benefits are unknown. The aim of this randomised controlled trial is to evaluate the long-term clinical effectiveness and cost-effectiveness of a 6-week group-based outpatient physiotherapy intervention following knee replacement. Methods/design: Two hundred and fifty-six patients waiting for knee replacement because of osteoarthritis will be recruited from two orthopaedic centres. Participants randomised to the usual-care group (n = 128) will be given a booklet about exercise and referred for physiotherapy if deemed appropriate by the clinical care team. The intervention group (n = 128) will receive the same usual care and additionally be invited to attend a group-based outpatient physiotherapy class starting 6 weeks after surgery. The 1-hour class will be run on a weekly basis over 6 weeks and will involve task-orientated and individualised exercises. The primary outcome will be the Lower Extremity Functional Scale at 12 months post-operative. Secondary outcomes include: quality of life, knee pain and function, depression, anxiety and satisfaction. Data collection will be by questionnaire prior to surgery and 3, 6 and 12 months after surgery and will include a resource-use questionnaire to enable a trial-based economic evaluation. Trial participation and satisfaction with the classes will be evaluated through structured telephone interviews. The primary statistical and economic analyses will be conducted on an intention-to-treat basis with and without imputation of missing data. The primary economic result will estimate the incremental cost per quality-adjusted life year gained from this intervention from a National Health Services (NHS) and personal social services perspective. Discussion: This research aims to benefit patients and the NHS by providing evidence on the long-term effectiveness and cost-effectiveness of outpatient physiotherapy after knee replacement. If the intervention is found to be effective and cost-effective, implementation into clinical practice could lead to improvement in patients’ outcomes and improved health care resource efficiency