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Background Context
Tobacco smoking is an injurious habit associated with a number of chronic disorders. Its influence on disc metabolism and degeneration including lumbar spinal stenosis (LSS) has been investigated in the literature.Purpose
We aimed to investigate whether tobacco smoking is an independent risk factor for undergoing surgical intervention for LSS.Study Design/Setting
This is a prospective cohort study.Patient Sample
The patient sample of 331,941 workers was derived from a Swedish nationwide occupational surveillance program for construction workers.Outcome Measure
The outcome measure included the incidence of undergoing surgical intervention for LSS in tobacco smokers versus no smokers.Materials and Methods
At inclusion, age, sex, body mass index (BMI), workers' job title, and self-reported smoking habits were registered. The workers were divided into four categories: never smoked, former smoker, moderate current (1–14 cigarettes/day), and heavy current (≥15 cigarettes/day). Patients who underwent a surgically treated LSS were defined using the relevant International Classification of Diseases (ICD) disease code derived from the Swedish National Patient Register.Results
A total of 331,941 participants were included in the analysis. Forty-four percent of the participants were non-smokers, 16% were former smokers, 26% were moderate smokers, and 14% were heavy smokers. The vast majority of construction workers were males (95%). During the average follow-up of 30.7 years, 1,623 participants were surgically treated for LSS. The incidence rate ratio (IRRs) of LSS varied across smoking categories, with the highest values found in heavy smokers. Compared with non-smokers, all smoking categories show an increased incidence of surgically treated LSS. The findings were consistent even when the comparison was performed for participants with BMIs between 18.5 and 25 and for participants aged between 40 and 74 years.Conclusions
Tobacco smoking is associated with an increased incidence of surgically treated LSS. The effect seems to be dose related, whereby heavy smokers have a higher risk than moderate or former smokers. 相似文献Material and methods — 4 observers with different levels of experience with radiographic measurements analyzed 77 routine preoperative hip radiographs of children with SCFE. Inter- and intraobserver reliability was evaluated.
Results — The interobserver reliability analysis for the 4 observers showed for CF an ICC of 0.99 (CI 0.97–0.99) and for Billing an ICC of 0.99 (CI 0.98–0.99). The interobserver reliability analysis for 2 observers showed for HSA an ICC of 0.98 (CI 0.97–0.99).
Intraobserver reliability (2 observers) showed a mean difference below 1° for all 3 methods and with a 95% limit of agreement not exceeding ±6.8°.
Interpretation — We found good reliability for both intra- and interobserver measurements of all 3 methods used for the assessment of the slip angle on routine preoperative lateral hip radiographs. 相似文献