title: Predisposing factors for dural tear in patients undergoing lumbar spine surgery.
abstract: OBJECT The purpose of this prospective cohort study was to identify risk factors for incidental durotomies in lumbar spine surgery. The authors hypothesized that the incidence of durotomy would be higher in cases involving multiple operations. METHODS The authors prospectively evaluated 523 patients who underwent lumbar and thoracolumbar spine surgery. They compared data on patients in whom a dural tear occurred and those in whom a dural tear did not occur. Data from patients in whom a dural tear occurred were compared with data from patients who did not experience durotomy. The data included basic demographic information, intraoperative data, and clinical information from a medical record review. RESULTS One hundred thirty-one patients underwent discectomy and 392 patients underwent laminectomy. Among the 131 patients who underwent discectomy 6 patients had a dural tear. Among the 392 patients who underwent discectomy 49 patients had dural tear. Patients with incidental durotomy were older (mean 65 ± 13 vs 60 ± 14 years of age; p = 0.044, t-test), and had longer surgery (146 ± 59 vs 110 ± 54 minutes; p = 0.025, t-test), compared with the patients without dural tear. The incidence of dural tear was more common in patients with a history of previous spine surgery (p < 0.001). CONCLUSIONS In patients who underwent lumbar and thoracolumbar spine surgery for degenerative problems, previous surgery and older age were found to be predisposing factors for dural tear.
authors.affiliation: Department of Orthopedic Surgery and Spine Unit, Assaf Harofeh Medical Center, Zerifin, Israel, affiliated with the Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel; and 
authors.forename: Yossi
authors.initials: Y
authors.lastname: Smorgick
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Baker
authors.forename: Harry
authors.initials: H
authors.lastname: Herkowitz
authors.forename: David
authors.initials: D
authors.lastname: Montgomery
authors.forename: Siddharth A
authors.initials: SA
authors.lastname: Badve
authors.forename: Casey
authors.initials: C
authors.lastname: Bachison
authors.forename: Steven
authors.initials: S
authors.lastname: Ericksen
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Fischgrund
mesh_terms: D000368:Aged; D017586:Diskectomy; D004388:Dura Mater / Q000293:injuries* / Q000601:surgery; D005260:Female; D006801:Humans; D007049:Iatrogenic Disease; D007796:Laminectomy; D008159:Lumbar Vertebrae / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011446:Prospective Studies; D012307:Risk Factors
keywords: BMI = body mass index; dural tear; laminectomy; lumbar; microdiscectomy; predisposing factors; revision surgery