Proceedings of the NASS 20th Annual Meeting / The Spine Journal 5 (2005) 1S–189S36S

DISCLOSURES: No disclosures.CONFLICT OF INTEREST: No conflicts.

doi: 10.1016/j.spinee.2005.05.069

5:4368. MRI indicators of SPECT positive facet diseaseAnthony Kim, MD, Michael Wang, MD; University of SouthernCalifornia, Los Angeles, CA, USA

BACKGROUND CONTEXT: Many reports have indicated that the facetjoints are a common cause of axial low back pain. However, a majorproblem with diagnosing facet disease has been the poor correlation betweenradiographic signs of joint degeneration and pain symptoms. SPECT radio-nuclide scanning has proven to be one of the more reliable and objectivetechniques to demonstrate the facet syndrome. However, MRI is a muchmore commonly employed test in patients with low back pain. Correlationsbetween SPECT and MRI could prove useful for diagnosing patients withfacet disease.PURPOSE: The purpose of this study was to determine if specific character-istics of the facet joints on MRI could predict a positive SPECT scan.STUDY DESIGN/SETTING: This study was a retrospective blinded anal-ysis of the imaging findings on MRI and SPECT scanning. Facet jointswere graded for SPECT radionuclide uptake on a four-point scale.PATIENT SAMPLE: Eighteen patients with severe axial back pain whohad undergone both SPECT and MRI scanning of the lumbar spine and hadincreased radionuclide uptake in at least one facet joint. These patientswere selected out of a total of 252 patients seen over a 2-year period, theremainder of whom had negative SPECT scans. 129 facet joints from L2/3to L5/S1 were investigated; levels that had been treated surgically werenot considered.OUTCOME MEASURES: Quantitative and morphometric measurementswere obtained from the axial MRI images. Imaging characteristics andquantification for the two modalities were obtained by different observersurgeons blinded to the results of the other test.METHODS: Staistical analysis of the imaging results were obtained usingpositive and negative predictive values.RESULTS: Abnormal SPECT activity was identified in 37 joints, andstructural findings on T2 MRI images correlated with SPECT activity.Facet cartilage discontinuity was identified in 78 joints. Discontinuity hada sensitivity of 0.79 and specificity of 0.45. Lateral breaches in the synovialjoint identified by a “hook-like” appearance in the joint were identified in23 joints. This finding had a sensitivity of 0.49 and specificity of 0.95.CONCLUSIONS: MRI evidence of discontinuity in the articular cartilageof the lumbar facet joints was a sensitive indicator of a “hot” facet joint,while breaches in the synovial capsule were highly specific for a positiveSPECT test. These findings may aid physicians in the identification ofsymptomatic facet disease.DISCLOSURES: No disclosures.CONFLICT OF INTEREST: No conflicts.

doi: 10.1016/j.spinee.2005.05.070

5:4969. Transincisionally placed epidural catheters for postoperativeanalgesia in instrumented lumbar spinal fusion surgeryJeffrey Coe, MD, Jeffrey Kanel, MD, Christopher Viale, MD,Randall Seago, MD, Iqbal Mirza, MD; Center for Spinal Deformity andInjury, Los Gatos, CA, USA

BACKGROUND CONTEXT: The use of epidural catheters for postopera-tive analgesia in spine surgery has been previously reported. The techniquedescribed herein varies from previously described intraoperative epiduralcatheterization techniques with epidural catheter placement through a non-

operated interspace rather than though an open laminectomy defect therebygiving the same control of catheter insertion as percutaneously placedcatheters. Furthermore leakage of the infusion solution into the wound viathe laminectomy defect is minimized and analgesic efficacy is maximized.PURPOSE: Is this new technique for immediate postoperative pain man-agement safe? Is it practical and effective in achieving postoperative paincontrol?STUDY DESIGN/SETTING: See “Methods” below.PATIENT SAMPLE: 151 consecutive patients who underwent posteriorlumbar spinal fusion with instrumentation by one of three surgeons.OUTCOME MEASURES: Conditions that prevented catheter placementand complications associated with epidural catheter placement and periop-erative analgesic infusion were logged. Immediate postoperative patientfunction was evaluated and supplemental parenteral analgesic requirementswas assessed.METHODS: All 151 patients were consented for postoperative epiduralanalgesia. Oneof two anesthesiologistsprovidedperioperativeanestheticandpain management care for each patient. Technique: Prior to fascial closurean intact epidural interspace one or two levels cephalad to the most cephalad-instrumented segment is exposed. Using a paramedian approach, an 18gauge Crawford needle is advanced into the epidural space under loss ofresistance to preservative free normal saline. A 20 gauge epidural catheteris then introduced and advanced 2 cm. A 15 cm Touhy-Schiff needleis introduced through the skin approximately 12 cm cephalad to the uppermargin of the incision and advanced until the of the needle appears adjacentto the catheter, deep to the fascia. The catheter is then passed retrogradethrough the Crawford needle. The catheter thus exits the skin site wellabove the most cephalad aspect of the wound. A test dose is administered andthe infusion (usually a dilute mixture of preservative-free hydromorphoneand preservative-free clonidine) is begun in the post anesthesia care unit,once the patient is awake. The patient is converted to oral analgesic therapyand the epidural catheter is removed prior to discharge between postopera-tive days 2 and 5.RESULTS: Two of the 151 patients did not have catheter placement dueto coagulopathy. None of the 149 catheterized patients developed anycomplication directly or indirectly related to catheter insertion techniqueor its presence. Patients began in-hospital rehabilitation with their cathetersin place with mobilization being as or more rapid than similar patients usingother forms of pain management. The catheterized patients used less break-through narcotic as well. The vast majorityof these patients were converted tooral analgesics with only a few requiring conversion to intravenous narcoticanalgesia, and had a shorter length of stay than those treated with otherforms of pain management.CONCLUSIONS: This newly described technique of postoperative painmanagement appears safe, practical and effective. It minimizes impairmentof patient sensorium compared with parenteral analgesic techniques therebyexpediting impatient rehabilitation and discharge.DISCLOSURES: No disclosures.CONFLICT OF INTEREST: No conflicts.

doi: 10.1016/j.spinee.2005.05.071

Wednesday, September 28, 20055:31–6:31 PM

SIPP 7: Lumbar Fusion Outcomes

5:3170. SF36 outcomes after lumbar spine fusion: amulticenter experienceSteven Glassman, MD1, Matthew F. Gornet, MD2, Charles Branch,MD3, David Polly, Jr., MD4, John Peloza, MD5, James D. Schwender,MD4, Leah Carreon, MD1; 1Leatherman Spine Center, Louisville, KY,USA; 2Missouri Bone and Joint Center, St. Louis, MO, USA; 3Wake

Proceedings of the NASS 20th Annual Meeting / The Spine Journal 5 (2005) 1S–189S 37S

5:3771. Bilateral canal decompression with unilateral laminotomyfor mono- or multisegemental lumbar stenosis: clinicalradiological resultsJae-Taek Hong1, Sang Won Lee1*, Byung-Chul Son1, Jae-Hoon Sung1,In-Soo Kim1, Moon Chan Kim2; 1Catholic University of Korea,St. Vincent Hospital, Suwon, Kyong-Gi, South Korea; 2CatholicUniversity of Korea, Kang Nam St Marys’ hospital, Seoul, South Korea

BACKGROUND CONTEXT: Laminectomy has been used widely inthe treatment of lumbar spinal stenosis. Destruction of the spinal bonystructure, instability and peridural scar formation are the main problems withthis procedure. To overcome these disadvantages, many procedures havebeen reported. Technical variations of lumbar laminectomy include unilat-eral laminotomy, bilateral laminotomies, and open door type laminoplasty.However, they have never become widespread, not only because of thecomplicated procedures but also because there is little data related to postop-erative stability, clinical and radiological results that support adequatedecompression of the spinal canal and acceptable clinical outcome. Al-though ipsilateral canal decompression by laminotomy has also been re-ported to be effective in the literature, there have been few articlesinvestigating the clinical and radiological results of contralateral decom-pression by ipsilateral laminotomy.PURPOSE: The purpose of the current study was to assess the adequacyof ipsilateral and contralateral canal decompression and long-term outcomefollowing bilateral canal decompression with unilateral laminotomy and toinvestigate the postoperative problems.STUDY DESIGN/SETTING: Retrospective study.PATIENT SAMPLE: Subjects were 22 patients with mono- or multi-segmental lumbar stenosis who had suffered from both leg claudicationand treated by bilateral canal decompression using unilateral laminotomy,and who were followed for at least 6 months. L45 stenosis was found in17 patients, and L34 and L5S1 stenosis was seen in 5 and 8 patientsrespectively. Four patients demonstrated multilevel stenosis.OUTCOME MEASURES: Using the Oswestry disability score and VASpain score, clinical symptoms including both leg pains and LBP werequantified before surgery and 6 months after surgery to calculate im-provement rates. Furthermore, the discrepancy of dural sac widening be-tween the ipsilateral and contralateral side measured by radiologicalmorphometric index (AP diameter, width of ipsilateral and contralateraldural sac which were divided by mid-sagittal plane along spinous process)was statistically analyzed. Dural sac diameter was calculated by preopera-tive and postoperative MRI or CT myelography.METHODS: Our surgical procedures of spinal canal enlargement usingunilateral laminotomy were performed for all patients. No other fusionprocedure was performed jointly.RESULTS: The mean follow-up time was 12. 2 months. All patientsimproved clinically and radiologically after this procedure. The meanOswestry disability score was 42.3 preoperatively and 12.1 postoperatively.The mean dural sac widening of ipsilateral side was 2.5 mm and the meandural sac widening of contralateral side was 1.5 mm, which was statisticallysignificant (p�.002). However, the VAS improvement (Preoperative VASscore–Postoperative VAS score) of each leg pain was 4.5 (ipsilateral side)and 4.4 (contralateral side) respectively, which was statistically insignificant(p�.66). There was one case of dural tearing during the procedure andtwo cases of transient paresthesia (less than 2 weeks) of contralateral nerveroot. No iatrogenic instability was observed during the follow-up period.CONCLUSIONS: With this technique, the important integrity of the spinalosseous and ligamentous structures is preserved, and a significant enlarge-ment of the spinal canal area is achieved. This technique is enough todecompress the contralateral canal to achieve good clinical outcome withouttroublesome complications. Further long-term follow-up is needed to evalu-ate spinal stability in these patients.DISCLOSURES: No disclosures.CONFLICT OF INTEREST: No conflicts.

doi: 10.1016/j.spinee.2005.05.073

Forest University, Winston-Salem, NC, USA; 4University of Minnesota,Minneapolis, MN, USA; 5Center for Spine Care–Frisco, Dallas,TX, USA

BACKGROUND CONTEXT: Historically, the success of lumbar fusionprocedures has been evaluated based primarily on fusion rate. Increasingly,this gauge is being supplanted by the use of patient based health statusmeasures. The largest studies using these measures are IDE trials, whichgenerate excellent data but are limited by strict enrollment criteria, with anidealized study population.PURPOSE: To examine health outcomes in a large sample of lumbarfusions performed in standard clinical practice.STUDY DESIGN/SETTING: Multi-center retrospective review of pro-spectively collected SF-36 and ODI after one or two level lumbar fusions,using a variety of surgical techniques.PATIENT SAMPLE: 497 patients (270 F, 227 M) between 17–86 yrs(mean 49) completed preoperative and one or two year postoperative SF-36 and ODI. All patients had one (n�323) or two (n�173) level lumbarfusions; 60 had prior lumbar decompression. Prior nonunions wereexcluded.OUTCOME MEASURES: SF-36, ODI.METHODS: Demographic and surgical data, and postoperative assess-ments were collected. Outcomes were analyzed based on variables includingage, gender, BMI, prior decompression, surgical technique and levels fused.RESULTS: SF-36 and ODI showed significant improvement at one andtwo years postoperatively in all groups (p�.0001). SF-36 PCS improved amean 9.9 points (n�497) at one year and 9.5 points (n�225) at twoyears. ODI improved a mean 20.2 points (n�418) at one year and 22.1points (n�141) at two years. There was no incremental improvement ordeterioration between one and two years postoperatively. There was nodifferential improvement in SF-36 PCS or ODI based on age, BMI orsmoking status. Better overall health status, pre- and postoperatively, wasnoted in younger, nonsmoking, and normal weight patients. There were125 patients who had an ALIF, 119 who had posterior fusion, 155 withPLIF/TLIF or and 95 with Ant/Post fusion. The posterior and PLIF/TLIFgroups were significantly older (p�.001) and had more females (p�.01)than either the ALIF, or Ant/Post groups. There was also a significantdifference in the number of levels fused (p�.001), with one level fusionscomprising 80% in the ALIF group, 70% in the posterior group, 64% inthe PLIF/TLIF group, and 42% in the Ant/Post group. The Ant/Post groupdemonstrated poorer health status and greater disability pre- and postopera-tively than theothergroups.Controlling forage, genderand levels fused, therewas a greater improvement in the ALIF group at one year postoperatively(p�.03), and in the ALIF and posterior fusion groups at two years postopera-tively (p�.02). Patients who had a prior decompression had significantlyless improvement in SF-36 PCS than unoperated patients (p�.005). Therewas no difference in ODI improvement between previously operated andunoperated patients. There was no difference in SF-36 PCS or ODI improve-ment between patients who had a one or two level fusion.CONCLUSIONS: This multi-center study shows that, regardless of tech-nique, lumbar spine fusion results in significant improvement in patientbased health outcome measures at one and two years postoperatively. Age,gender, BMI, and smoking altered general health status, but did not diminishimprovement after surgery. Patients with prior decompression obtained lessbenefit. There may be a potential advantage in the ALIF and posteriorfusion approaches, but demographic differences limit any conclusions.Our data suggest that the benefit of lumbar spine fusion seen in IDEtrials can be obtained in a wider patient population in a general practicesetting.DISCLOSURES: No disclosures.CONFLICT OF INTEREST: Author (SG) Consultant: Medtronic SofamorDanek;Author (SG)Other:Royalties received fromMedtronicSofamorDanek;Author (SG) Grant Research Support: Medtronic Sofamor Danek

doi: 10.1016/j.spinee.2005.05.072