Methodological aspects of a randomized within-patient concurrent controlled design for clinical trials in spine surgery.

INTRODUCTION: Randomized controlled trials are considered the highest level of evidence, but their feasibility in the surgical field is severely hampered by methodological and practical issues. Concurrent comparison between the experimental and control conditions within the same patient can be an effective strategy to mitigate some of these challenges and improve generalizability, mainly by the elimination of between-patient variability and reduction of the required sample size. This article aims (1) to describe the methodological aspects of a randomized within-patient controlled trial and (2) to quantify the added value of this design, based on a recently completed randomized within-patient controlled trial on bone grafts in instrumented lumbar posterolateral spinal fusion. METHODS: Boundary conditions for the application of the randomized within-patient controlled trial design were identified. Between-patient variability was quantified by the intraclass correlation coefficient and concordance in the primary fusion outcome. Sample size, study duration and costs were compared with a classic randomized controlled trial design. RESULTS: Boundary conditions include the concurrent application of the experimental and control conditions to identical but physically separated sites. Moreover, the outcome of interest should be local, uncorrelated and independently assessable. The spinal fusion outcomes within a patient were found to be more similar than between different patients (intraclass correlation coefficient 32% and concordance 64%), demonstrating a clear effect of patient-related factors. The randomized within-patient controlled trial design allowed a reduction of the sample size to one-third of a parallel-group randomized controlled trial, thereby halving the trial duration and costs. CONCLUSION: When suitable, the randomized within-patient controlled trial is an efficient design that provides a solution to some of the considerable challenges of a classic randomized controlled trial in (spine) surgery. This design holds specific promise for efficacy studies of non-active bone grafts in instrumented posterolateral fusion surgery.

Down-titration and discontinuation strategies of tumour necrosis factor-blocking agents for rheumatoid arthritis in patients with low disease activity.

BACKGROUND: Anti-tumour necrosis factor (TNF) agents are effective in treating people with rheumatoid arthritis (RA), but are associated with (dose-dependent) adverse effects and high costs. To prevent overtreatment, several trials have assessed the effectiveness of down-titration compared with continuation of the standard dose. This is an update of a Cochrane Review published in 2014. OBJECTIVES: To evaluate the benefits and harms of down-titration (dose reduction, discontinuation, or disease activity-guided dose tapering) of anti-TNF agents on disease activity, functioning, costs, safety, and radiographic damage compared with usual care in people with RA and low disease activity. SEARCH METHODS: We searched MEDLINE, Embase, Web of Science and CENTRAL (29 March 2018) and four trial registries (11 April 2018) together with reference checking, citation searching, and contact with study authors to identify additional studies. We screened conference proceedings (American College of Rheumatology and European League Against Rheumatism 2005-2017). SELECTION CRITERIA: Randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing down-titration (dose reduction, discontinuation, disease activity-guided dose tapering) of anti-TNF agents (adalimumab, certolizumab pegol, etanercept, golimumab, infliximab) to usual care/no down-titration in people with RA and low disease activity. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. MAIN RESULTS: One previously included trial was excluded retrospectively in this update because it was not an RCT/CCT. We included eight additional trials, for a total of 14 studies (13 RCTs and one CCT, 3315 participants in total) reporting anti-TNF down-titration. Six studies (1148 participants) reported anti-TNF dose reduction compared with anti-TNF continuation. Eight studies (2111 participants) reported anti-TNF discontinuation compared with anti-TNF continuation (three studies assessed both anti-TNF discontinuation and dose reduction), and three studies assessed disease activity-guided anti-TNF dose tapering (365 participants). These studies included data on all anti-TNF agents, but primarily adalimumab and etanercept. Thirteen studies were available in full text, one was available as abstract. We assessed the included studies generally at low to moderate risk of bias; our main concerns were bias due to open-label treatment and unblinded outcome assessment. Clinical heterogeneity between the trials was high. The included studies were performed at clinical centres around the world and included people with early as well as established RA, the majority of whom were female with mean ages between 47 and 60. Study durations ranged from 6 months to 3.5 years.We found that anti-TNF dose reduction leads to little or no difference in mean disease activity score (DAS28) after 26 to 52 weeks (high-certainty evidence, mean difference (MD) 0.06, 95% confidence interval (CI) -0.11 to 0.24, absolute risk difference (ARD) 1%) compared with continuation. Also, anti-TNF dose reduction does not result in an important deterioration in function after 26 to 52 weeks (Health Assessment Questionnaire Disability Index (HAQ-DI)) (high-certainty evidence, MD 0.09, 95% CI 0.00 to 0.19, ARD 3%). Next to this, anti-TNF dose reduction may slightly reduce the proportion of participants switched to another biologic (low-certainty evidence), but probably slightly increases the proportion of participants with minimal radiographic progression after 52 weeks (moderate-certainty evidence, risk ratio (RR) 1.22, 95% CI 0.76 to 1.95, ARD 2% higher). Anti-TNF dose reduction may cause little or no difference in serious adverse events, withdrawals due to adverse events and proportion of participants with persistent remission (low-certainty evidence).Results show that anti-TNF discontinuation probably slightly increases the mean disease activity score (DAS28) after 28 to 52 weeks (moderate-certainty evidence, MD 0.96, 95% CI 0.67 to 1.25, ARD 14%), and that the RR of persistent remission lies between 0.16 and 0.77 (low-certainty evidence). Anti-TNF discontinuation increases the proportion participants with minimal radiographic progression after 52 weeks (high-certainty evidence, RR 1.69, 95% CI 1.10 to 2.59, ARD 7%) and may lead to a slight deterioration in function (HAQ-DI) (low-certainty evidence). It is uncertain whether anti-TNF discontinuation influences the number of serious adverse events (due to very low-certainty evidence) and the number of withdrawals due to adverse events after 28 to 52 weeks probably increases slightly (moderate-certainty evidence, RR 1.46, 95% CI 0.75 to 2.84, ARD 1% higher).Anti-TNF disease activity-guided dose tapering may result in little or no difference in mean disease activity score (DAS28) after 72 to 78 weeks (low-certainty evidence). Furthermore, anti-TNF disease activity-guided dose tapering results in little or no difference in the proportion of participants with persistent remission after 18 months (high-certainty evidence, RR 0.89, 95% CI 0.75 to 1.06, ARD -9%) and may result in little or no difference in switching to another biologic (low-certainty evidence). Anti-TNF disease activity-guided dose tapering may slightly increase proportion of participants with minimal radiographic progression (low-certainty evidence) and probably leads to a slight deterioration of function after 18 months (moderate-certainty evidence, MD 0.2 higher, 0.02 lower to 0.42 higher, ARD 7% higher), It is uncertain whether anti-TNF disease activity-guided dose tapering influences the number of serious adverse events due to very low-certainty evidence. AUTHORS' CONCLUSIONS: We found that fixed-dose reduction of anti-TNF, after at least three to 12 months of low disease activity, is comparable to continuation of the standard dose regarding disease activity and function, and may be comparable with regards to the proportion of participants with persistent remission. Discontinuation (also without disease activity-guided adaptation) of anti-TNF is probably inferior to continuation of treatment with respect to disease activity, the proportion of participants with persistent remission, function, and minimal radiographic damage. Disease activity-guided dose tapering of anti-TNF is comparable to continuation of treatment with respect to the proportion of participants with persistent remission and may be comparable regarding disease activity.Caveats of this review are that available data are mainly limited to etanercept and adalimumab, the heterogeneity between studies, and the use of superiority instead of non-inferiority designs.Future research should focus on the anti-TNF agents infliximab and golimumab; assessment of disease activity, function, and radiographic outcomes after longer follow-up; and assessment of long-term safety, cost-effectiveness, and predictors for successful down-titration. Also, use of a validated flare criterion, non-inferiority designs, and disease activity-guided tapering instead of fixed-dose reduction or discontinuation would allow researchers to better interpret study findings and generalise to clinical practice.

The reliability and validity of goniometric elbow measurements in adults: A systematic review of the literature.

BACKGROUND: The universal goniometer is a simple measuring tool. With this review we aimed to investigate the reliability and validity of the universal goniometer in measurements of the adults' elbow. METHODS: Preferred Reporting Items for Systematic reviews and Meta-Analysis guidelines were followed and our study protocol was published online at PROSPERO. A literature search was conducted on relevant studies. Methodological quality was assessed using the Quality Appraisal of Diagnostic Reliability (QAREL) scoring system. RESULTS: Out of 697 studies yielded from our literature search, 12 were included. Six studies were rated as high quality. The intrarater reliability intraclass correlation coefficient ranged from 0.45 to 0.99, the interrater reliability ranged from intraclass correlation coefficient 0.53-0.97. One study providing instructions on goniometric alignment did not find a difference in expert versus non-expert examiners. Another study in which examiners were not instructed found a higher interrater reliability in expert examiners. One study investigating the validity of the goniometer in elbow measurements found a maximum standard error of the mean of 11.5° for total range of motion. DISCUSSION: Overall, the studies showed high intra- and interrater reliability of the universal goniometer. The reliability of the universal goniometer in non-expert examiners can be increased by clear instructions on goniometric alignment.

Percutaneous laser disc decompression versus conventional microdiscectomy for patients with sciatica: Two-year results of a randomised controlled trial.

Background Percutaneous laser disc decompression is a minimally invasive treatment, for lumbar disc herniation and might serve as an alternative to surgical management of sciatica. In a randomised trial with two-year follow-up we assessed the clinical effectiveness of percutaneous laser disc decompression compared to conventional surgery. Materials and methods This multicentre randomised prospective trial with a non-inferiority design, was carried out according to an intent-to-treat protocol with full institutional review board approval. One hundred and fifteen eligible surgical candidates, with sciatica from a disc herniation smaller than one-third of the spinal canal, were randomly allocated to percutaneous laser disc decompression ( n = 55) or conventional surgery ( n = 57). The main outcome measures for this trial were the Roland-Morris Disability Questionnaire for sciatica, visual analogue scores for back and leg pain and the patient's report of perceived recovery. Results The primary outcome measures showed no significant difference or clinically relevant difference between the two groups at two-year follow-up. The re-operation rate was 21% in the surgery group, which is relatively high, and with an even higher 52% in the percutaneous laser disc decompression group. Conclusion At two-year follow-up, a strategy of percutaneous laser disc decompression, followed by surgery if needed, resulted in non-inferior outcomes compared to a strategy of microdiscectomy. Although the rate of reoperation in the percutaneous laser disc decompression group was higher than expected, surgery could be avoided in 48% of those patients that were originally candidates for surgery. Percutaneous laser disc decompression, as a non-surgical method, could have a place in the treatment arsenal of sciatica caused by contained herniated discs.

Failed back (surgery) syndrome: time for a paradigm shift.

1. The group of patients with so-called 'failed back surgery syndrome' (FBSS) is very diverse. Published studies evaluating the outcome of surgical treatment vary widely in terms of surgical interventions that were performed. Results from these papers cannot be generally applied to all people who have persisting complaints after low back surgery. 2. The literature search that was performed demonstrated that the articles that scored as acceptable on assessment bias demonstrated a low to moderate patient-perceived recovery percentage. The only randomized controlled trial on this topic did not demonstrate a difference between instrumented fusion and cognitive intervention and exercise. 3. Current research does not show repeat surgery to be successful in 'FBSS patients', but clinical practice indicates that, in a small, carefully selected group, repeat surgery can yield rewarding results. However, parameters that make a patient prone to recover from a subsequent surgical intervention cannot be found in the literature. 4. The term 'failed back surgery syndrome' implies a causative role of surgery in a problem situation; failed back surgery syndrome is frequently regarded as failed back surgery. The literature does not, however, provide evidence for this. 5. It is important to inform the patient adequately to shape realistic expectations. Preoperative evaluation of parameters evaluating the psychological condition could help to better predict the outcome of surgery. 6. The term 'failed back surgery syndrome' has been demonstrated to be an ill-defined term, serving as a container for all kinds of back and leg problems, and wrongly implying a definite role for the surgical intervention in the aetiology. We suggest shifting the paradigm to 'failed back syndrome'. With this term we suggest defining those patients with back and radicular leg pain without a structural deficit, or with a structural deficit that has a low a priori chance of benefiting from a surgical intervention.