Minimally Invasive Treatment (XLIF) of Adjacent Segment Disease after prior Lumbar Fusions

ISPUB.COM The Internet Journal of Minimally Invasive Spinal Technology Volume 3 Number 4 Minimally Invasive Treatment (XLIF) of Adjacent Segment Disease after prior Lumbar Fusions W Rodgers, C Cox, E Gerber Citation W Rodgers, C Cox, E Gerber. Minimally Invasive Treatment (XLIF) of Adjacent Segment Disease after prior Lumbar Fusions. The Internet Journal of Minimally Invasive Spinal Technology. 2008 Volume 3 Number 4. Abstract Although adjacent segment degeneration (ASD) is a well-described process after lumbar fusion and there has been significant discussion in the literature about the surgical treatments of this process using traditional open techniques, there has been little discussion about the application of minimally invasive techniques to this complex problem. 100 consecutive patients with symptomatic ASD were treated with minimally invasive spinal fusion using the extreme lateral interbody fusion (XLIF) technique. We examined this group to determine perioperative complications and early outcomes and compared this to prior traditional surgical treatments. Length of hospitalization averaged 1.13 days and hemoglobin change 1.34 g. There were no transfusions or infections. Visual analog pain scoring decreased from 8.6 preoperatively to 2.8 at 6 months postoperatively (67 patients). Minimally invasive surgery offers good early symptomatic improvement in patients with ASD with shorter hospitalization and fewer complications than traditional modalities. t in patients with ASD with shorter hospitalization and fewer complications than traditional modalities. W.B. Rodgers, MD Spine Midwest 200 St. Mary s Medical Plaza, Ste. 301 Jefferson City, MO, USA 65101 brodgers@spinemidwest.com INTRODUCTION Adjacent segment disease after lumbar fusion has been well characterized in the literature. The incidence of this disease ranges in some studies from 25% to 40% with the radiographic incidence approaching 100% and the symptomatic incidence nearly 25%. Many theories have been proposed for this entity but most researchers believe that the increased biomechanical stress on the motion segment adjacent to the fused area leads to changes in the intradiscal pressure with resultant hypermobility of the adjacent segment. This hypermobility leads to facet joint degeneration and further radiographic and clinical deterioration ( 12345678910111213141516 ). It has also been shown in the literature that re-operations for adjacent segment disease through either traditional posterior or anterior approaches are associated with some improvement in neurologic and functional status but are also associated with significant morbidity and are operatively technically demanding ( 910 ). The risks associated with anterior approaches of the spine, particularly revision anterior approaches of the spine, include injury to the abdominal contents, iliac vasculature, or sympathetic plexus ( 18 ). Posterior revision approaches also carry many similar risks but in addition devitalize the paraspinous musculature and carry risks of inadvertent durotomies and traction neurapraxia ( 1920 ). Recently a novel minimally disruptive spine procedure called extreme lateral interbody fusion or XLIF (NuVasive, Inc., San Diego, CA) has been developed. XLIF is a 90 off midline or true lateral approach that allows for large graft placement, excellent disk height restoration, and indirect decompression at the stenotic motion segment ( 2122232425262728 ). Since the introduction of the XLIF technique to North America in late 2003, early studies have shown its safety and efficacy ( 262728 ). The technique has been reported for use in a variety of degenerative conditions including degenerative scoliosis and revision of failed disk arthroplasties ( 2324 ). In this brief report we outline our experience using the XLIF procedure in the treatment of adjacent segment disease. MATERIALS AND METHODS The authors treated a prospective series of 100 patients with adjacent segment degeneration after prior lumbar fusion 1 of 6

using the XLIF technique. Of these 100 patients (59 F, 41M; average age 62.2 years; average BMI 31.2), 79 had undergone prior instrumented posterior fusion procedures, 15 had undergone prior uninstrumented posterior fusion procedures, and 6 had undergone anterior lumbar interbody (ALIF) fusion procedures. Figure 1 Figure 1: Adjacent segment degeneration above and below a prior L4-5 fusion. incisions. Safe passage to the retroperitoneal space is assured by gentle blunt dissection. As the psoas muscle is traversed, the lumbosacral plexus is protected by the use of automated electrophysiology via dynamic discrete evoked EMG thresholding (NeuroVision, NuVasive, Inc.). Exposure is achieved with an expandable three-bladed retractor (MaXcess, NuVasive, Inc.), which allows for direct illuminated visualization facilitating diskectomy and complete anterior column stabilization using a large loadbearing implant (CoRoent XL, NuVasive, Inc.) that rests on the dense ring apophysis bilaterally. All cases were performed using a graft composite composed of local bone from the vertebral bodies, bone marrow aspirate and demineralized bone matrix with corticocancellous allograft chips (Optecure CCC, Exactech, Gainesville, FL). All but one case included supplemental fixation (NuVasive, Inc.): unilateral pedicle screw-rod constructs ( 43 ), bilateral pedicle screw-rod constructs ( 4 ), trans-facetal screws ( 1 ), and supplemental lateral instrumentation ( 51 ). In our experience, unilateral pedicle screw-rod constructs appear to be as clinically stable as bilateral constructs; biomechanical data suggests that this fixation should be adequate ( 30 ). RESULTS In a previous publication ( 28 ), we delineated the fundamental tenets of XLIF surgery, which include careful patient positioning, gentle retroperitoneal dissection, meticulous psoas traverse using neurological monitoring, adequate diskectomy and fusion site preparation, and proper interbody implant placement. The XLIF procedure is performed through two 3-4 cm 2 of 6

Figure 2 Figure 2: Postoperative anterior-posterior radiograph showing anterior stabilization with XLIF interbody implants at L3-4 and L4-5 and AxiaLIF at L5-S1 (Trans1, Wilmington, NC). Figure 3 Table 1: Perioperative results Figure 4 Figure 3: CT assessment of fusion one year after XLIF. Note solid bridging of bone in the area of XLIF implant aperture. Procedures were performed without incident in short OR times and with little intraoperative blood loss: average hemoglobin change from pre- to post-op was 1.34g); and recovery was quick: patients stayed in the hospital an average of 1.13 days. Disk heights were increased an average of 3.4mm, which was maintained out to last followup at 6 months. Slip in those with spondylolisthesis was reduced by an average 3.4mm, also maintained through the 6 month follow-up. Fusion was assessed by Lenke score ( 18 ) with averages of 2.3 at 3 months and 2.0 at 6 months, indicating good progression of fusion at these time points. Clinical outcomes were also very good, with an average improvement in VAS pain scores of 5.8 from pre-op to 6 months. No patient required blood transfusions and no patient developed a wound infection. There were 9 complications in the entire group: 3 of 6

Figure 5 Figure 4: Lateral X-ray at 2 weeks post-op identifying vertebral body fracture with implant subsidence. Figure 6 Figure 5: Postoperative lateral X-ray showing XLIF reconstruction above prior ALIF. DISCUSSION Adjacent segment disease has long been a concern of spinal surgeons treating patients with lumbar fusions. The incidence of this entity may be as high as 40% and is thought to be secondary to the transmission of stress across the immobilized segment ( 12345678910111213141516 ). Our experience using XLIF technology in adjacent segment disease has been most encouraging. By avoiding the complications associated with anterior or posterior procedures ( 181920 ), our patients have routinely been discharged in less than two days and none of them has required blood transfusions. The clinical and radiographic indicators have all improved commensurately and the overall outcome is most encouraging. Of particular note is the absence of infectious complications, which has been as high 14% in some reports ( 4 ). Transfusion and length of stay data has not been reported in the previous literature but the minimally invasive results appear encouraging. No procedure is without complications as our results indicate, but the complications are manageable and less common than reported using traditional techniques ( 4691516 ). References 1. Lee CK. Accelerated degeneration of the segment adjacent to a lumbar fusion. Spine 1988; 13:375-377. 2. Lehmann TR, Spratt KF, Tozzi JE, et al. Long-term follow-up of lower lumbar fusion patients. Spine 1987;12:97-104. 3. Aota Y, Kumano K, Hirabayashi S. Postfusion instability at the adjacent segments after rigid pedicle screw fixation for degenerative lumbar spinal disorders. J Spinal Disord 1995;8:464-73. 4. Whitecloud TS III, Davis JM, Olive PM. Operative treatment of the degenerated segment adjacent to a lumbar fusion. Spine 1994;19:531-6. 5. Penta M, Sandhu A, Fraser RD. Magnetic resonance imaging assessment of disc degeneration 10 years after anterior lumbar interbody fusion. Spine 1995;20:743-7. 6. Rahm MD, Hall BB. Adjacent-segment degeneration after lumbar fusion with instrumentation: a retrospective study. J Spinal Disord 1996;9:392-400. 7. Schlegel JD, Smith JA, Schleusener RL. Lumbar motion segment pathology adjacent to thoracolumbar, lumbar, and lumbosacral fusions. Spine 1996;21:970-81. 8. Hambly MF, Wiltse LL, Raghavan N, et al. The transition zone above a lumbosacral fusion. Spine 1998;23:1785-92. 9. Phillips FM, Carlson GD, Bohlman HH, et al. Results of surgery for spinal stenosis adjacent to previous lumbar fusion. J Spinal Disord 2000;13:432-7. 10. Chen WJ, Lai PL, Niu CC, et al. Surgical treatment of adjacent instability after lumbar spine fusion. Spine 2001;26:E519-24. 11. Throckmorton TW, Hilibrand AS, Mencio GA, et al. The impact of adjacent level disc degeneration on health status outcomes following lumbar fusion. Spine 2003;28:2546-50. 12. Chow DH, Luk KD, Evans JH, et al. Effects of short anterior lumbar interbody fusion on biomechanics of neighboring unfused segments. Spine 1996;21:549-55. 13. Whitecloud III TS, Pagano P. Management of failed surgery: adjacent segment to fusion. In: Herkowitz HN, Dvorak J, Bell G, Nodin M, Grob D, eds. The lumbar spine, 3rd ed, Philadelphia: Lippincott Williams & Wilkins, 4 of 6

2004:884-9. 14. Axelsson P, Johnsson R, Stromqvist B. The spondylolytic vertebra and its adjacent segment: mobility measured before and after posterolateral fusion. Spine 1997;22:414-7 15. Ghiselli G, Wang JC, Bhatia NN, Hs WK, Dawson EG. Adjacent segment degeneration in the lumbar spine. J Bone Joint Surg Am 2004: 86;1497-1503. 16. Park P, Garton HJ, Gala VC, Hoff JT, McGillicuddy JE. Adajacent segment disease after lumbar or lumbosacral fusion: Review of the literature. Spine 2004; 29: 1938-1944. 17. Bridwell K, Lenke, G, McEnery K, Bladus C, Blanke K: Anterior Fresh Frozen Structural Allografts in the Thoracic and Lumar Spine Do They Work if Combined With Posterior Fusion and Instrumentation in Adult Patients With Kyphosis or Anterior Column Defects? Spine 1995; 20:1410-1418. 18. Sasso R., et al., Analysis of operative complications in a series of 471 anterior lumbar interbody fusion procedures, Spine 2005; 30: 670-674. 19. Park Y, Ha JW. Comparison of one-level posterior lumbar interbody fusion performed with a minimally invasive approach or a traditional open approach, Spine 2007; 32: 537-43. 20. Salerni AA. A minimally invasive approach for posterior lumbar interbody fusion. Neurosurg Focus. 2002;13:e6. 21. Heim SE & Pimenta L, Surgical Anatomy and Approaches to the Anterior Lumbar and Lumbosacral Spine (2005) Chapter 97, in: Spinal Instrumentation Surgical Techniques Edited by DH Kim, AR Vaccaro, RG Fessler; (Thieme Medical Publishers, NY), pp. 706-11. 22. Ozgur BM, Aryan HE, Pimenta L, Taylor WR, Extreme Lateral Interbody Fusion XLIF): a novel surgical technique for anterior lumbar interbody fusion Spine J 2006; 6: 435-43 23. Pimenta L, Diaz RC, Guerrero LG, Charite lumbar artificial disc retrieval: use of a lateral minimally invasive technique, J. Neurosurg Sp 2006; 5:556-61. 24. Phillips F, Diaz R, Pimenta L: Minimally-invasive fusion (XLIF ) in the treatment of symptomatic degenerative lumbar scoliosis. Poster presented at North American Spine Society (2005), Philadelphia, PA. 25. Smith W: XLIF: One surgeon s interbody fusion technique of choice. Poster presented at AANS/CNS Joint Section on Spine (2006), Orlando, FL. 26. Hyde J, Seits M: Mid- to long-term follow-up of patients with XLIF treatment of lumbar degenerative conditions. International Meeting on Advanced Spine Techniques (2007), Paradise Island, Bahamas. 27. Wright N XLIF- the United States experience 2003-4. International Meeting on Advanced Spine Techniques (2005), Banff, Canada. 28. Rodgers WB, Cox CS, Gerber EJ: Experience and early results with a minimally invasive technique for anterior column support through extreme Lateral Interbody Fusion: XLIF. Musculoskeletal Review 2007; 1:28-32. 29. Bess RS, Bacchus K, Vance R, Cornwall GB, Pimenta L, Brodke D: Lumbar Biomechanics with Extreme Lateral Interbody Fusion (XLIF ) Cage Constructs International Meeting on Advanced Spine Techniques (2007), Paradise Island, Bahamas. 5 of 6

Author Information W.B. Rodgers, M.D. Curtis S. Cox, M.D. Edward J. Gerber, P.A.-C. 6 of 6