Proceedings of the NASS 18 th Annual Meeting / The Spine Journal 3 (2003) 67S–171S 91S RESULTS: In rats, bone nodules were formed in separate experiments with the non-lyophilized TAT-LMP-1 protein at doses of 0.6nM (4 of 4 implants), 1.2nM (4/4), or 1.6nM (2/3). The lyophilized protein appeared more stable and made bone within the same experiment at doses of 1.2, 2.5, 5 nM (4/4 in each) and 10 nM (2/3). The challenging rabbit posterolateral spine fusion model also demonstrated the successful use of recombinant TAT-LMP-1 pro- tein. Spine fusion masses were formed in 2 different experiments with the non-lyophylized TAT-LMP-1 protein at doses of 5.0 nM (3/3) or 5.5 nM (2/ 2). The lyophilized TAT-LMP-1 protein was successful at doses of 5.0 nM (3/ 3) and 6.0 nM (2/3) within a single experiment. All rabbits (3/3) in a followup experiment achieved bilateral solid spine fusion with the dose of 5.0 nM on one side and 5.5 nM on the opposite side of the spine. DISCUSSION: To date induction of bone formation by the intracellular protein LMP-1 has required gene therapy techniques to deliver its cDNA. This study now shows that a short peptide sequence (TAT) added to recom- binant LMP-1 protein will facilitate the entry of the protein itself directly into buffy coat cells and initiate ectopic bone formation in rats and spine fusions in adult rabbits. The TAT-LMP-1 fusion protein was effective at 5.0 nM which is substantially lower than the dose of 100 nM used with delivery of other TAT proteins. Efficacy at surprisingly low doses has also been seen with LMP-1 cDNA delivered with gene therapy vectors and may be due to the potent nature of this intracellular regulatory protein and its ability to induce several potent osteoinductive genes including BMPs. CONCLUSIONS: This study shows that LMP-1 can be delivered as a recombinant fusion protein without the challenges of gene therapy. The TAT-LMP-1 fusion protein retained its activity when lyophilized and was stable and easily stored in that form. A non-gene therapy approach could be advantageous for delivery of LMP-1 in short term/local healing processes such as spine fusion. DISCLOSURES: Device or drug: LMP-1. Status: not approved. CONFLICT OF INTEREST: Scott Boden, MD, grant research support and consultant: Medtronic. doi: 10.1016/S1529-9430(03)00231-6 Thursday, October 23, 2003 4:34–5:04 PM Concurrent Focused Reviews: Surgical Complications 4:34 52. Complications associated with the use of kenalog during lumbar decompression surgery Jeffrey Dick 1 , David Holte, MD 1 ; 1 Orthopaedic Consultants, P.A., Edina, MN, USA HYPOTHESIS: The application of kenalog to the dura during lumbar decompression surgery is associated with an increased incidence of late cerebrospinal fluid leakage and infection. METHODS: From June 4, 2001 to June 26, 2002 all patients who under- went lumbar decompression by one of the two authors were retrospectively reviewed. Data was obtained from the operative note, operative record and clinic notes. Patients were followed for an avearage of 4 months postoperatively with length of follow up ranging from 0 to 7 months. RESULTS: During the period of the review 231 patients underwent lumbar decompression surgery by one of the two authors. Diagnoses included 141 primary disc herniations, 36 recurrent disc herniations, 51 patients with spinal stenosis and three synovial cysts. Steroids were placed in the epidural space intraoperatively in 189 patients. In 98 patients the steroid used was kenalog, celestone was used in 72 patients, aristospan in 7, betamethasone in 7, dexamethasone in 4 and depo medrol in 2 (Table 1). Of the 98 kenalog patients 11 developed late CSF leakage and 4 developed wound infections. In the group where no steroid was used introperatively 2 patients developed an infection and 1 developed a late spinal fluid leak. No infections or late CSF leaks developed in the remaining steroid groups. DISCUSSION: Prior to June 2001 it was the authors practice to place a small amount of celestone in the epidural space prior to closure after Table 1 Complications of epidural kenalog Number Infection % Infection CSF leak % CSF leak Kenalog 98 4 4.1 11 11.2 Celestone 72 0 0 0 0 None 42 2 4.8 1 2.4 Aristospan 7 0 0 0 0 Betamethasone 7 0 0 0 0 Dexamethasone 4 0 0 0 0 Depo medrol 2 0 0 0 0 Total 232 6 2.6 12 5.2 a lumbar decompression. Shortly after that date a national shortage of celestone developed and our hospitals had difficulty obtaining it. The phar- macies substituted various steroids but kenalog was readily available and was used extensively until a marked increase in complications was observed. The 11.2% incidence of late CSF leaks and 4.1% incidence of post operative wound infection in the kenalog group were statistically significant compared to the celestone group. The incidence of infection in the kenalog group was not significant compared to the group where no intraoperative steroids were used. The high complication rate resolved after the use of kenalog was discontinued. We hypothesize that this difference is due to the high potency of kenalog compared to celestone and the other substitutes but further study is needed to determine the mechanism by which kenalog weakens the dura. CONCLUSIONS: There is an unacceptable incidence of late post operative CSF leakage when kenalog is placed in the epidural space during lumbar decompression. The authors recommend that the use of kenalog in the epidural space be avoided. DISCLOSURES: Device or drug: glucocorticoids. Status: approved. CONFLICT OF INTEREST: No conflicts. doi: 10.1016/S1529-9430(03)00232-8 4:38 53. Proximal segment degeneration after posterior lumbosacral fusions (L4-S1 and L5-S1) Nitin Bhatia, MD 1 , Gary Ghiselli, MD 1 , Jeffrey Wang 1 , Wellington Hsu, MD 1 , Edgar G. Dawson 2 ; 1 University of California, Los Angeles, Los Angeles, CA, USA; 2 University of California, Los Angeles, Santa Monica, CA, USA HYPOTHESIS: There is current controversy regarding the degeneration of proximal lumbar segments following posterior spinal fusion at the L4-S1 and L5-S1 intervals. The purpose of this study was to determine the survivorship of the proximal segments in patients undergoing these lumbosacral fusions. METHODS: Eighty-five consecutive patients (average age 49 years, range 15–85 years) having isolated L4-S1 or L5-S1 posterior spinal fusions by a single surgeon were included in this study. There were 46 females and 39 males with an average follow-up of 6.9 years (range 1.0 to 33 years). Thirty patients underwent L5-S1 posterior spinal fusion, and 55 underwent L4-S1 posterior fusion. A survivorship analysis was performed to determine the degeneration at the proximal lumbar segments. Radiographs were ana- lyzed for arthritic degeneration post-operatively. RESULTS: Of the total 85 patients assessed, 63 (74%) had no evidence of symptomatic degeneration at the proximal levels requiring additional sur- gery. Two patients developed spinal stenosis and underwent a posterior de- compression without fusion at 14 years and 15 years, respectively, after the index procedure. Twenty other patients required further fusion surgery at an average of 11 years after the initial fusion (range 2.0 to 33 years). Thirteen patients underwent extension of the fusion to the immediately proximal level, 5 required fusion extension two levels proximally, and 2 underwent fusion ending distally at L3. The most common cause for reoperation was adjacent segment degeneration. Although there was a trend of increasing arthritic grade at the proximal levels post-operatively, there was no correlation be- tween preoperative arthritic grade and the need for further surgery.