Relationship between sedimentation sign and morphological grade in symptomatic lumbar spinal stenosis.

PURPOSE: We aimed to study the relationship between two morphological parameters recently described on MRI images in relation to lumbar spinal stenosis (LSS): the first is the sedimentation sign (SedS) and the second is the morphological grading of lumbar stenosis. MATERIALS AND METHODS: MRIs from a total of 137 patients were studied. From those, 110 were issued from a prospective database of symptomatic LSS patients, of whom 73 were treated surgically and 37 conservatively based on symptom severity. A third group consisting of 27 subjects complaining of low back pain (LBP) served as control. Severity of stenosis was judged at disc level using the four A to D grade morphological classification. The presence of a SedS was judged at pedicle level, above or below the site of maximal stenosis. RESULTS: A positive SedS was observed in 58, 69 and 76 % of patients demonstrating B, C and D morphology, respectively, but in none with grade A morphology. The SedS was positive in 67 and 35 % of the surgically and conservatively treated patients, respectively, and in 8 % of the LBP group. C and D morphological grades were present in 97 and 35 % of patients in the surgically and conservatively treated group, respectively, and in 18 % of the LBP group. Presence of a positive SedS carried an increased risk of being submitted to surgery in the symptomatic LSS group (OR 3.5). This risk was even higher in the LSS patients demonstrating grade C or D morphology (OR 65). DISCUSSION AND CONCLUSION: One-third of surgically treated LSS patients do not present a SedS. This sign appears to be a lesser predictor of treatment modality in our setting of symptomatic LSS patients compared to the severity of stenosis judged by the morphological grade.

Premature Discontinuation of Randomized Trials in Critical and Emergency Care: A Retrospective Cohort Study.

OBJECTIVES: Randomized clinical trials that enroll patients in critical or emergency care (acute care) setting are challenging because of narrow time windows for recruitment and the inability of many patients to provide informed consent. To assess the extent that recruitment challenges lead to randomized clinical trial discontinuation, we compared the discontinuation of acute care and nonacute care randomized clinical trials. DESIGN: Retrospective cohort of 894 randomized clinical trials approved by six institutional review boards in Switzerland, Germany, and Canada between 2000 and 2003. SETTING: Randomized clinical trials involving patients in an acute or nonacute care setting. SUBJECTS AND INTERVENTIONS: We recorded trial characteristics, self-reported trial discontinuation, and self-reported reasons for discontinuation from protocols, corresponding publications, institutional review board files, and a survey of investigators. MEASUREMENTS AND MAIN RESULTS: Of 894 randomized clinical trials, 64 (7%) were acute care randomized clinical trials (29 critical care and 35 emergency care). Compared with the 830 nonacute care randomized clinical trials, acute care randomized clinical trials were more frequently discontinued (28 of 64, 44% vs 221 of 830, 27%; p = 0.004). Slow recruitment was the most frequent reason for discontinuation, both in acute care (13 of 64, 20%) and in nonacute care randomized clinical trials (7 of 64, 11%). Logistic regression analyses suggested the acute care setting as an independent risk factor for randomized clinical trial discontinuation specifically as a result of slow recruitment (odds ratio, 4.00; 95% CI, 1.72-9.31) after adjusting for other established risk factors, including nonindustry sponsorship and small sample size. CONCLUSIONS: Acute care randomized clinical trials are more vulnerable to premature discontinuation than nonacute care randomized clinical trials and have an approximately four-fold higher risk of discontinuation due to slow recruitment. These results highlight the need for strategies to reliably prevent and resolve slow patient recruitment in randomized clinical trials conducted in the critical and emergency care setting.