Rationale behind motion preservation devices is to eliminate the accelerated adjacent-level effects (ALE) associated with spinal fusion. We evaluated multidirectional flexibilities and ALEs of StabilimaxNZ® and simulated fusion applied to a decompressed spine. StabilimaxNZ® was applied at L4–L5 after creating a decompression (laminectomy of L4 plus bilateral medial facetectomy at L4–L5). Multidirectional Flexibility and Hybrid tests were performed on six fresh cadaveric human specimens (T12–S1). Decompression increased average flexion–extension rotation to 124.0% of the intact. StabilimaxNZ® and simulated fusion decreased the motion to 62.4 and 23.8% of intact, respectively. In lateral bending, corresponding increase was 121.6% and decreases were 57.5 and 11.9%. In torsion, corresponding increase was 132.7%, and decreases were 36.3% for fusion, and none for StabilimaxNZ® ALE was defined as percentage increase over the intact. The ALE at L3–4 was 15.3% for StabilimaxNZ® versus 33.4% for fusion, while at L5–S1 the ALE were 5.0% vs. 11.3%, respectively. In lateral bending, the corresponding ALE values were 3.0% vs. 19.1%, and 11.3% vs. 35.8%, respectively. In torsion, the corresponding values were 3.7% vs. 20.6%, and 4.0% vs. 33.5%, respectively. In conclusion, this in vitro study using Flexibility and Hybrid test methods showed that StabilimaxNZ® stabilized the decompressed spinal level effectively in sagittal and frontal planes, while allowing a good portion of the normal rotation, and concurrently it did not produce significant ALEs as compared to the fusion. However, it did not stabilize the decompressed specimen in torsion.
This is a preview of subscription content, log in to check access.
Buy single article
Instant access to the full article PDF.
Price includes VAT for USA
Subscribe to journal
Immediate online access to all issues from 2019. Subscription will auto renew annually.
This is the net price. Taxes to be calculated in checkout.
Abumi K, Panjabi MM, Kramer KM, et al (1990) Biomechanical evaluation of lumbar spinal stability after graded facetectomies. Spine 15:1142–1147
Ames CP, Acosta FL Jr, Chamberlain RH, Larios AE, Crawford NR (2005) Biomechanical analysis of a newly designed bioabsorbable anterior cervical plate. Invited submission from the joint section meeting on disorders of the spine and peripheral nerves, March 2005. J Neurosurg Spine 3:465–470
Andersson GB (1999) Epidemiological features of chronic low-back pain. Lancet 354:581–585
Cunningham BW, Lewis SJ, Long J, et al (2002) Biomechanical evaluation of lumbosacral reconstruction techniques for spondylolisthesis: an in vitro porcine model. Spine 27:2321–2327
Cunningham BW, Lowery GL, Serhan HA, et al (2002) Total disc replacement arthroplasty using the AcroFlex lumbar disc: a non-human primate model. Eur Spine J 11(Suppl 2):S115–S123
Dmitriev AE, Cunningham BW, Hu N, et al (2005) Adjacent level intradiscal pressure and segmental kinematics following a cervical total disc arthroplasty: an in vitro human cadaveric model. Spine 30:1165–1172
Erulkar JS, Grauer JN, Patel TC, Panjabi MM (2001) Flexibility analysis of posterolateral fusions in a New Zealand white rabbit model. Spine 26:1125–1130
Goel V, Grauer J, Patel T, et al (2005) Effects of charite artificial disc on the implanted and adjacent spinal segment mechanics using a hybrid testing protocol. Spine 30:2755–2764
Hilibrand AS, Robbins M (2004) Adjacent segment degeneration and adjacent segment disease: the consequences of spinal fusion? Spine J 4:190S–194S
Kotani Y, Cunningham BW, Abumi K, et al (2005) Multidirectional flexibility analysis of cervical artificial disc reconstruction: in vitro human cadaveric spine model. J Neurosurg Spine 2:188–194
Luo X, Pietrobon R, Sun SX, Liu GG, Hey L (2004) Estimates and patterns of direct health care expenditures among individuals with back pain in the United States. Spine 29:79–86
Nibu K, Panjabi MM, Oxland T, Cholewicki J (1997) Multidirectional stabilizing potential of BAK interbody spinal fusion system for anterior surgery. J Spinal Disord 10:357–362
Panjabi MM (1988) Biomechanical evaluation of spinal fixation devices: I. A conceptual framework. Spine 13:1129–1134
Panjabi MM (2007) Hybrid multidirectional test method to evaluate spinal adjacent-level effects. Clin Biomech 22(3):257–265
Panjabi MM, Malcolmson G, Teng E, Tominaga Y, Henderson G (2006) Hybrid adjacent-level testing of lumbar Charite discs versus fusions. Spine 32:959–966
Patwardhan AG, Havey RM, Carandang G, et al (2003) Effect of compressive follower preload on the flexion-extension response of the human lumbar spine. J Orthop Res 21:540–546
Schlegel JD, Smith JA, Schleusener RL (1996) Lumbar motion segment pathology adjacent to thoracolumbar, lumbar, and lumbosacral fusions. Spine 21:970–981
Yoshimoto H, Ito M, Abumi K, et al (2004) A retrospective radiographic analysis of subaxial sagittal alignment after posterior C1-C2 fusion. Spine 29:175–181
We gratefully acknowledge a gift from Applied Spine Technology, New Haven, CT, USA which made this research possible.
About this article
Cite this article
Panjabi, M.M., Henderson, G., James, Y. et al. StabilimaxNZ® versus simulated fusion: evaluation of adjacent-level effects. Eur Spine J 16, 2159–2165 (2007). https://doi.org/10.1007/s00586-007-0444-5
- Pedicle Screw
- Spinal Fusion
- Artificial Disc
- Follower Load
- Spine Specimen