Proceedings of the NASS 19 th Annual Meeting / The Spine Journal 4 (2004) 3S–119S 22S multiple comparisons was used to calculate the change in the AAOS pain scores at 1, 3 and 6 months compared to baseline. METHODS: 47 patients with low back pain, scheduled for facet joint injections, were prospectively enrolled and randomized into Groups A and B with ratio of 2:1. In Group A, patients had bone SPECT prior to facet injection. Group A patients with a positive SPECT were injected at the abnormal level(s) identified on the scan (Group A1). In case of negative scan (Group A2), the level(s) for injection was decided as in Group B. In Group B patients received facet injection without bone SPECT at the levels indi- cated by the referring physician. All patients completed a pain and function questionnaire (AAOS Lumbar Spine Survey) immediately before the facet injection, and at 1, 3 and 6 months. A cost analysis was performed using the current Medicare reimbursement rates at our institution. RESULTS: The change in the pain score at one month was significantly higher (p0.004) in Group A1 than in the other two groups. In Group A1, 13/15 patients had significant improvement in pain score at one month. In contrast, there were only 2/16 patients with a significant improvement in Group A2 and 5/16 patients in Group B. The difference between groups was not significant at 6 months (p=0.067). In the patients with positive scans the number of facets injected was decreased from the 60 originally indicated by the referring physician to 27. The Medicare cost was reduced from $2,191 on average per patient to $1,865 with the use of bone SPECT. CONCLUSIONS: Bone SPECT can help identify patients who would benefit from facet joint injections. Facet joint injection has limited value in patients with negative bone SPECT. Use of bone SPECT also resulted in a decrease in the overall cost. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No Conflicts. doi: 10.1016/j.spinee.2004.05.039 4:56 39. Smoking, diabetes and excessive preoperative epidural steroid administration are risk factors for intraoperative dural tears Nicholas Ahn, MD 1 , Uri Ahn, MD 2 , Zachary Post, MD 3 , Thomas Salsbury, MD 3 , Harpreet Basran, MD 3 , Jason Datta 3 , Cody Harlan 3 , Brian Ipsen 3 , William Reed, Jr. MD 4 , Glenn Amundson, MD 4 , Alexander Bailey, MD 4 , William Hopkins, MD 4 , Gunnar Andersson 5 , Howard An 5 ; 1 Heartland Hand and Spine Orthopaedic Center/ University of Missouri- Kansas City, Overland Park, KS, USA; 2 New Hampshire Spine Institute, Bedford, NH, USA; 3 University of Missouri- Kansas City, Kansas City, MO, USA; 4 Heartland Hand and Spine Orthopaedic Center, Overland Park, KS, USA; 5 Rush University / Rush- Presbyterian-St. Luke’s Medical Center, Chicago, IL, USA BACKGROUND CONTEXT: It is well known in the general surgery liter- ature that smoking, diabetes, and steroid use are risk factors for weakened fascial tissues and wound dehiscence. Given that the dural sac is composed of a very thin layer of fibrous tissue that is thinner than but not unlike the abdominopelvic fascia, it would stand to reason that intraoperative dural tears may be more common in patients who smoke, have diabetes, or who were exposed to excessive preoperative epidural steroid injections. PURPOSE: This study was performed to determine risk factors for intraop- erative dural tears during lumbar decompression surgery. STUDY DESIGN/SETTING: We performed a retrospective review of patients who had undergone primary lumbar decompression surgery for spinal stenosis between 1998 and 2003. All cases were performed in one of eight different hospitals which included two university/acamedic centers and six community hospitals. PATIENT SAMPLE: 1867 patients who had undergone primary lumbar decompression surgery for spinal stenosis with or without fusion between 1998 and 2003 were retrospectively studied. OUTCOME MEASURES: Cases in which an intraoperative dural leak had occurred were noted. METHODS: Information on age, sex, smoking history, diabetes, alcohol- ism, number of levels decompressed, number of levels fused, use of instru- mentation, and number of preoperative epidural injections 6 months before surgery were also collected. Stepwise logistic regression analyses were then used to determine the association between intraoperative dural tears and each of the independent variables while controlling for confounding factors. RESULTS: 123 patients in our study group sustained an intraoperative dural leak. Logistic regression analyses demonstrated a significant associa- tion between dural tears and smoking (OR=3.4, p=0.02), diabetes (OR=2.3, p=0.04), and 3 preoperative epidural steroid injections 6 months prior to surgery (OR=1.6, p=0.04). There was no association between intraoperative dural tears and the remaining independent variables (p0.05). The odds of sustaining an intraoperative dural leak were particu- larly high in patients with two or more of these risk factors (OR=6.7, p=0.04). CONCLUSIONS: Intraoperative dural tears are significantly higher in patients who smoke, have diabetes, or who were subjected to excessive epidural steroid injections (3 in 6 months prior to surgery). In addition, patients with a combination of the above risk factors have a markedly increased risk of inadvertent intraoperative durotomy. The surgeon should exhibit additional caution in these patients and warn them of the increased risk of intraoperative dural tears. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No Conflicts. doi: 10.1016/j.spinee.2004.05.040 Wednesday, October 27, 2004 4:35–5:15 PM Concurrent Sessions 2B: Trauma Surgical Treatment 4:35 40. A prospective randomized clinical trial comparing anterior versus posterior stabilization for unilateral facet injuries of the cervical spine Brian Kwon, MD 1 , Marcel Dvorak, MD 1 , Charles Fisher, MD 2 , Michael Boyd, MD 2 , Peter Wing, MB 2 , Caroline Abramson, MA 1 , Allan Aludino, BSc 2 , Alexei Schwartzman, BSc 2 , Jennifer Brown, PT 3 , John Cobb, PT 3 ; 1 University of British Columbia, Vancouver, British Columbia, Canada; 2 University of British Columbia, British Columbia, Canada; 3 Vancouver General Hospital, British Columbia, Canada BACKGROUND CONTEXT: Unilateral facet fractures and dislocations are common injuries in the subaxial cervical spine. Surgical stabilization can be achieved posteriorly with lateral mass screws and/or wiring techniques, or anteriorly with discectomy and cervical plating. The optimal surgical approach, however, has not been established. PURPOSE: In this study, we sought to compare anterior versus posterior stabilization for unilateral facet injuries in a prospective randomized fashion. STUDY DESIGN/SETTING: Prospective randomized controlled trial conducted in a single level 1 trauma center. PATIENT SAMPLE: Individuals with a unilateral facet injury were en- rolled in the study if they had an injury deemed to be suitable to single- level anterior or posterior stabilization, were over the age of 16 and were able to understand and use a patient-controlled analgesia unit. Ex- cluded were individuals with a spinal cord injury, significant vertebral body injury, concomitant injuries or pre-existing medical conditions affecting mobility, pre-existing tolerance to opioids, or pre-existing cervical pathol- ogy. Apriori power calculation indicated 20 subjects per group. OUTCOME MEASURES: The primary outcome measure was the time required by patients to post-operatively achieve a standard set of dis- charge criteria which included independent mobility, an acceptable level of pain control on oral analgesics, and medical stabilization. Secondary outcome measures included acute post-operative pain and wound complica- tions. Radiographic alignment and fusion, and both generic and disease- specific outcome measures (SF-36 and NASS questionnaires) were assessed at 3, 6 and 12 months post-operatively.