Comparison of Unilateral Hemilaminotomy and Bilateral Hemilaminotomy According to Dural Sac Area in Lumbar Spinal Stenosis[*]

Abstract

Introduction: Unilateral hemilaminotomy (ULH) and/or bilateral hemilaminotomy (BLH) with limited facetectomy are defined approaches to decompress the thecal sac and exiting lumbar nerve roots without increasing the risk of subsequent spinal instability.

Methods: We retrospectively analyzed 18 cases with degenerative lumbar spinal stenosis (LSS) with BLH or ULH that was performed in 11 and 7 cases, respectively. Magnetic resonance imaging (MRI) was performed at the follow-up examination and dural sac area (DSA) was calculated on T₂-weighted MRI images and then compared statistically. In addition, the economic and functional status of the patients were evaluated with the Prolo scale.

Results: The mean preoperative values on the visual analogue scale (VAS) were 7.1 for lumbalgia and 7.0 for leg pain, respectively. These values were calculated as 4.8 and 4.4 at the follow-up, respectively. The VAS was significantly improved after operation compared to preoperative values (p=0.001). The mean value of the DSA was 84 (±32) mm² before the operation and 126 (±35) mm² at the follow-up and the comparison was statistically significant (p=0.001). No statistical correlation was found between VAS and DSA or between VAS and ULH-BLH groups, however, DSA of the BLH cases was significantly higher than in the ULH group (p=0.035). There was a significant negative correlation between VAS scores (back and leg pain) and Prolo status. However, there was no significant difference between DSA and Prolo scores, and between ULH or BLH groups in terms of Prolo scores.

Conclusion: A unilateral approach with bilateral decompression and bilateral approach with bilateral hemilaminotomy are both minimal invasive, adequate and safe approaches with excellent prognosis. However, BLH leads to a bigger expansion of DSA.

Key words

unilateral hemilaminotomy - bilateral hemilaminotomy - dural sac area - lumbar spinal stenosis

1 This paper was presented as an oral presentation during the Worldspine IV Congress (Istanbul, 2007).

References

• 1 Niggemeyer O, Strauss JM, Schulitz KP. Comparison of surgical procedures for degenerative lumbar spinal stenosis:a meta-analysis of the literature from 1975 to 1995.  Eur Spine J. 1997;  6 423-429
• 2 Yamazaki K, Yosida S, Ito T. et al . Postoperative outcome of lumbar spinal canal stenosis after fenestration: correlation with changes in intradural and extradural tube on magnetic resonance imaging.  J Orthop Surg. 2002;  10 136-143
• 3 Lange M, Hamburger C, Waidhauser E. et al . Surgical treatment and results in patients suffering from lumbar spinal stenosis.  Neurosurg Rev. 1993;  16 27-33
• 4 Schonstrom NSR, Bolender NF, Spengler DM. The pathomorphology of spinal stenosis as seen on CT scans of the lumbar spine.  Spine. 1985;  10 806-811
• 5 Benz RJ, Garfin SR. Current techniques of decompression of the lumbar spine.  Clin Orthop. 2001;  384 75-81
• 6 Caspar W, Papavero L, Sayler MK. et al . Precise and limited decompression for lumbar spinal stenosis.  Acta Neurochir. 1994;  131 130-136
• 7 diPiero CG, Helm GA, Shaffrey CI. et al . Treatment of lumbar spinal stenosis by extensive unilateral decompression and contralateral autologous bone fusion: operative technique and results.  J Neurosurg. 1996;  84 166-173
• 8 Fokter SK, Yerby SA. Patient-based outcomes for the operative treatment of degenerative lumbar spinal stenosis.  Eur Spine J. 2006;  15 1661-1669
• 9 Gelalis ID, Stafilas KS, Korompilias AV. et al . Decompressive surgery for degenerative lumbar spinal stenosis: long-term results.  Int Orthop. 2006;  30 59-63
• 10 Kleeman TJ, Hiscoe AC, Berg EE. Patient outcomes after minimally destabilising lumbar stenosis decompression.  Spine. 2000;  25 865-870
• 11 Nasca RJ. Rationale for spinal fusion in lumbar spinal stenosis.  Spine. 1989;  14 451-454
• 12 Spetzger U, Bertalanffy H, Reinges MHT. et al . Unilateral laminotomy for bilateral decompression of lumbar spinal stenosis.  Acta Neurochir (Wien). 1997;  139 397-403
• 13 Spratt KF, Keller TS, Szpalski M. et al . A predictive model for outcome after conservative decompression surgery for lumbar spinal stenosis.  Eur Spine J. 2004;  13 14-21
• 14 Thome C, Zevgaridis D, Leheta O. et al . Outcome after less-invasive decompression of lumbar spinal stenosis: a randomized comparison of unilateral laminotomy, bilateral laminotomy, and laminectomy.  J Neurosurg (Spine). 2005;  3 129-141
• 15 Tsai RY, Yaang R-S, Bray RS. Microscopic laminotomies for degenerative lumbar spinal stenosis.  J Spinal Disord. 1998;  11 389-394
• 16 Amundsen T, Weber H, Nordal HJ. et al . Lumbar spinal stenosis: conservative or surgical management? A prospective 10-year study.  Spine. 2000;  25 1424-1435
• 17 Jansson KA, Blomqvist P, Granath F. et al . Spinal stenosis surgery in Sweden 1987–1999.  Eur Spine J. 2003;  12 535-541
• 18 Ogikubo O, Forsberg L, Hansson T. The relationship between the cross-sectional area of the cauda equina and the preoperative symptoms in central lumbar spinal stenosis.  Spine. 2007;  32 1423-1428
• 19 Abumi K, Panjabi MM, Kramer KM. et al . Biomechanical evaluation of lumbar spinal stability after graded facetectomies.  Spine. 1990;  15 1142-1147
• 20 Boden SD, Martin C, Rudolph R. et al . Increase of motion between lumbar vertebrae after excision of the capsule and cartilage of the facets. A cadaver study.  J Bone Joint Surg [Am]. 1994;  76 1847-1853
• 21 Brunon J, Chazal J, Chirossel JP. et al . When is spinal fusion warranted in degenerative lumbar spinal stenosis?.  Rev Rhum (Engl Ed). 1996;  63 44-50
• 22 Carreon LY, Puno RM, Dimar JR. et al . Perioperative complications of posterior lumbar decompression and arthrodesis in older adults.  J Bone Joint Surg [Am]. 2003;  85 2089-2092
• 23 Fujita T, Kostuik JP, Huckell CB. et al . Complications of spinal fusion in adult patients more than 60 years of age.  Orthop Clin North Am. 1998;  29 669-678
• 24 Reeg SE. A review of comorbidities and spinal surgery.  Clin Orthop. 2001;  384 101-109
• 25 Haher TR, O'Brien M, Dryer JW. et al . The role of the lumbar facet joints in spinal stability.  Identification of alternative paths of loading. Spine. 1994;  19 2667-2671
• 26 Aryanpur J, Ducker T. Multilevel lumbar laminotomies: An alternative to laminectomy in the treatment of lumbar stenosis.  Neurosurgery. 1990;  26 429-433
• 27 Guiot BH, Khoo LT, Fessler RG. A minimally invasive technique for decompression of the lumbar spine.  Spine. 2002;  27 432-438
• 28 Poletti CE. Central lumbar stenosis caused by ligamentum flavum unilateral laminotomy for bilateral ligamentectomy: Preliminary report of two cases.  Neurosurgery. 1995;  37 343-347
• 29 Rosen DS, O'Toole JE, Eichholz KM. et al . Minimally invasive lumbar spinal decompression in the elderly: outcomes of 50 patients aged 75 years and older.  Neurosurgery. 2007;  60 503-510
• 30 Postacchini F. Spine update: Surgical management of lumbar spinal stenosis.  Spine. 1999;  24 1043-1047
• 31 Herno A, Partanen K, Talaslahti T. et al . Long-term clinical and magnetic resonance imaging follow-up assessment of patients with lumbar spinal stenosis after laminectomy.  Spine. 1999;  24 1533-1537
• 32 Lohman CM, Tallroth K, Kettunen JA. et al . Comparison of radiologic signs and clinical symptoms of spinal stenosis.  Spine. 2006;  31 1834-1840
• 33 Zheng F, Farmer JC, Sandhu HS. et al . A novel method for the quantitative evaluation of lumbar spinal stenosis.  HSSJ. 2006;  2 136-140
• 34 Olmarker K, Holm S, Rydevik B. Importance of compression onset rate for the degree of impairment of impulse propagation in experimental compression injury of the porcine cauda equina.  Spine. 1990;  15 416-419
• 35 Oland G, Hoff TG. Intraspinal cross-sectional area measured on myelography-computed tomography.  Spine. 1996;  21 1985-1989

1 This paper was presented as an oral presentation during the Worldspine IV Congress (Istanbul, 2007).

Correspondence