Research Papers

Nucleus Implantation: The Biomechanics of Augmentation Versus Replacement With Varying Degrees of Nucleotomy

[+] Author and Article Information
Marco Cannella, Shanee Allen, Argjenta Orana

Department of Material Science and Engineering,
Drexel University,
3141 Chestnut Street,
Philadelphia, PA 19104

Jessica L. Isaacs

Department of Mechanical Engineering
and Mechanics,
Drexel University,
3141 Chestnut Street,
Philadelphia, PA 19104

Edward Vresilovic

Department of Orthopedic Surgery,
Milton S. Hershey Medical Center,
Penn State University,
500 University Dr.,
Hershey, PA 17033

Michele Marcolongo

Department of Material Science and Engineering,
Drexel University,
3141 Chestnut Street,
Philadelphia, PA 19104
e-mail: marcolms@drexel.edu

1Corresponding author.

Contributed by the Bioengineering Division of ASME for publication in the Journal of Biomechanical Engineering. Manuscript received May 2, 2013; final manuscript received January 24, 2014; accepted manuscript posted March 6, 2014; published online April 10, 2014. Assoc. Editor: James C. Iatridis.

J Biomech Eng 136(5), 051001 (Apr 10, 2014) (9 pages) Paper No: BIO-13-1212; doi: 10.1115/1.4027056 History: Received May 02, 2013; Revised January 24, 2014; Accepted March 06, 2014

Nucleus pulposus replacement and augmentation has been proposed to restore disk mechanics in early stages of degeneration with the option of providing a minimally invasive procedure for pain relief to patients with an earlier stage of degeneration. The goal of this paper is to examine compressive stability of the intervertebral disk after either partial nucleus replacement or nuclear augmentation in the absence of denucleation. Thirteen human cadaver lumbar anterior column units were used to study the effects of denucleation and augmentation on the compressive mechanical behavior of the human intervertebral disk. Testing was performed in axial compression after incremental steps of partial denucleation and subsequent implantation of a synthetic hydrogel nucleus replacement. In a separate set of experiments, the disks were not denucleated but augmented with the same synthetic hydrogel nucleus replacement. Neutral zone, range of motion, and stiffness were measured. The results showed that compressive stabilization of the disk can be re-established with nucleus replacement even for partial denucleation. Augmentation of the disk resulted in an increase in disk height and intradiskal pressure that were linearly related to the volume of polymer implanted. Intervertebral disk instability, evidenced by increased neutral zone and ranges of motion, associated with degeneration can be restored by volume filling of the nucleus pulposus using the hydrogel device presented here.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.


White, A. A., and Panjabi, M. M., 1990, Clinical Biomechanics of the Spine, Lippincott, Philadelphia.
Walker, B. F., 2000, “The Prevalence of Low Back Pain: A Systematic Review of the Literature From 1966 to 1998,” J. Spinal Disord. Tech., 13(3), pp. 205–217. [CrossRef]
Vaccaro, A. R., 2005, Spine: Core Knowledge in Orthopaedics, Mosby Publishing, Philadelphia, PA.
Mossaad, M., Herkowitz, H., Dvorak, J., Bell, G., Nordin, M., and Grob, D., 2004, “Degenerative Lumbar Spondlyolisthesis With Spinal Stenosis: Natural History, Diagnosis, Clinical Presentation, and Nonoperative Treatment,” Lumbar Spine, 3, pp. 514–523. [CrossRef]
Adams, P., and Muir, H., 1976, “Qualitative Changes With Age of Proteoglycans of Human Lumbar Discs,” Ann. Rheum. Dis., 35(4), pp. 289–296. [CrossRef] [PubMed]
Bushell, G., Ghosh, P., Taylor, T., and Akeson, W., 1977, “Proteoglycan Chemistry of the Intervertebral Disks,” Clin. Orthop. Relat. Res., 129, pp. 115–123. [CrossRef] [PubMed]
Hedman, T. P., Kostuik, J. P., Fernie, G. R., and Heller, W. G., 1991, “Design of an Intervertebral Disc Prosthesis,” Spine, 16(6S), pp. S256–S260. [CrossRef] [PubMed]
Van Ooij, A., Oner, F. C., and Verbout, A. J., 2003, “Complications of Artificial Disc Replacement: A Report of 27 Patients With the Sb Charite Disc,” Spine, 28, pp. 369–383. [CrossRef]
Lehmann, T., Spratt, K., Tozzi, J., Weinstein, J., Reinarz, S., El-Khoury, G., and Colby, H., 1987, “Long-Term Follow-Up of Lower Lumbar Fusion Patients,” Spine, 12(2), pp. 97–104. [CrossRef] [PubMed]
Adams, M., McNally, D., and Dolan, P., 1996, “'Stress' Distributions Inside Intervertebral Discs. The Effects of Age and Degeneration, “J. Bone Joint Surg., Br. Vol., 78(6), pp. 965–972. [CrossRef]
Adams, M., Dolan, P., and Hutton, W., 1986, “The Stages of Disc Degeneration as Revealed by Discograms, “J. Bone Joint Surg., Br. Vol., 68(1), pp. 36–41.
Cunningham, B. W., Kotani, Y., McNulty, P. S., Cappuccino, A., and McAfee, P. C., 1997, “The Effect of Spinal Destabilization and Instrumentation on Lumbar Intradiscal Pressure: An in Vitro Biomechanical Analysis,” Spine, 22(22), pp. 2655–2663. [CrossRef] [PubMed]
Leong, J., Chun, S., Grange, W., and Fang, D., 1983, “Long–Term Results of Lumbar Intervertebral Disc Prolapse,” Spine, 8(7), pp. 793–799. [CrossRef] [PubMed]
Cinotti, G., Della Rocca, C., Romeo, S., Vittur, F., Toffanin, R., and Trasimeni, G., 2005, “Degenerative Changes of Porcine Intervertebral Disc Induced by Vertebral Endplate Injuries,” Spine, 30(2), pp. 174–180. [CrossRef] [PubMed]
Van Tulder, M. W., Assendelft, W. J., Koes, B. W., and Bouter, L. M., 1997, “Spinal Radiographic Findings and Nonspecific Low Back Pain: A Systematic Review of Observational Studies,” Spine, 22(4), pp. 427–434. [CrossRef] [PubMed]
Boden, S., Davis, D., Dina, T., Patronas, N., and Wiesel, S., 1990, “Abnormal Magnetic-Resonance Scans of the Lumbar Spine,” J. Bone Joint Surg. Am. Vol., 72, pp. 403–408.
Jensen, M. C., Brant-Zawadzki, M. N., Obuchowski, N., Modic, M. T., Malkasian, D., and Ross, J. S., 1994, “Magnetic Resonance Imaging of the Lumbar Spine in People Without Back Pain,” New Engl. J. Med., 331(2), pp. 69–73. [CrossRef]
Powell, M., Szypryt, P., Wilson, M., Symonds, E., and Worthington, B., 1986, “Prevalence of Lumbar Disc Degeneration Observed by Magnetic Resonance in Symptomless Women,” Lancet, 328(8520), pp. 1366–1367. [CrossRef]
Cholewicki, J., and McGill, S., 1996, “Mechanical Stability of the in Vivo Lumbar Spine: Implications for Injury and Chronic Low Back Pain,”Clin. Biomech., 11(1), pp. 1–15. [CrossRef]
Panjabi, M. M., 2003, “Clinical Spinal Instability and Low Back Pain,”J. Electromyogr. Kinesiol., 13(4), pp. 371–379. [CrossRef] [PubMed]
Bono, C. M., and Lee, C. K., 2004, “Critical Analysis of Trends in Fusion for Degenerative Disc Disease Over the Past 20 Years: Influence of Technique on Fusion Rate and Clinical Outcome,” Spine, 29(4), pp. 455–463. [CrossRef] [PubMed]
Bao, Q.-B., and Yuan, H. A., 2002, “New Technologies in Spine: Nucleus Replacement,” Spine, 27(11), pp. 1245–1247. [CrossRef] [PubMed]
Di Martino, A., Vaccaro, A. R., Lee, J. Y., Denaro, V., and Lim, M. R., 2005, “Nucleus Pulposus Replacement: Basic Science and Indications for Clinical Use,”Spine, 30(16S), pp. S16–S22. [CrossRef] [PubMed]
Joshi, A., Massey, C. J., Karduna, A., Vresilovic, E., and Marcolongo, M., 2009, “The Effect of Nucleus Implant Parameters on the Compressive Mechanics of the Lumbar Intervertebral Disc: A Finite Element Study, “J. Biomed. Mater. Res., Part B, 90(2), pp. 596–607. [CrossRef]
Arthur, A., Cannella, M., Keane, M., Singhatat, W., Vresilovic, E., and Marcolongo, M., 2010, “Fill of the Nucleus Cavity Affects Mechanical Stability in Compression, Bending, and Torsion of a Spine Segment, Which Has Undergone Nucleus Replacement,” Spine, 35(11), pp. 1128–1135. [CrossRef] [PubMed]
Cannella, M., Arthur, A., Allen, S., Keane, M., Joshi, A., Vresilovic, E., and Marcolongo, M., 2008, “The Role of the Nucleus Pulposus in Neutral Zone Human Lumbar Intervertebral Disc Mechanics,” J. Biomech., 41(10), pp. 2104–2111. [CrossRef] [PubMed]
Batterjee, K., Ray, C., and Osman, M., 2000, “One Year Followup on 17 Saudi Patients Implanted With a Prosthetic Disc Nucleus,” Proceedings of the Annual Meeting of the International Society for the Study of the Lumbar Spine.
Ray, C. D., 2002, “The Pdn® Prosthetic Disc-Nucleus Device,” Eur. Spine J., 11(2), pp. S137–S142. [CrossRef] [PubMed]
Nachemson, A., 1962, “Some Mechanical Properties of the Lumbar Intervertebral Discs,” Bull. Hosp. Jt. Dis., 23, pp. 130–143.
Joshi, A., Fussell, G., Thomas, J., Hsuan, A., Lowman, A., Karduna, A., Vresilovic, E., and Marcolongo, M., 2006, “Functional Compressive Mechanics of a PVA/PVP Nucleus Pulposus Replacement,” Biomaterials, 27(2), pp. 176–184. [CrossRef] [PubMed]
Kostuik, J. P., 1997, “Intervertebral Disc Replacement: Experimental Study,” Clin. Orthop. Relat. Res., 337, pp. 27–41. [CrossRef] [PubMed]
Fernström, U., 1965, “Arthroplasty With Intercorporal Endoprothesis in Herniated Disc and in Painful Disc,” Acta Chir. Scand. Suppl., 357, pp. 154–159.
Büttner–Janz, K., Schellnack, K., and Zippel, H., 1989, “Biomechanics of the Sb Charité Lumbar Intervertebral Disc Endoprosthesis,” Int. Orthop., 13(3), pp. 173–176. [CrossRef] [PubMed]
Knowles, F. L., 1954, “Apparatus for Treatment of the Spinal Column,” U.S. Patent No. 2,677,369.
Patil, A. A., 1982, “Artificial Intervertebral Disc,” U.S. Patent No. 4,309,777.
Buttner-Janz, K., Keller, A., and Lemaire, J.–P., 1995, “Intervertebral Disc Endoprosthesis,” U.S. Patent No. 5,401,269.
Steffee, A. D., 1991, “Artificial Disc,” U.S. Patent No. 5,071,437.
Zippel, H., 1991, “Charite Modulus—Concept, Experience, and Results,” The Artificial Disc, Springer-Verlag, Berlin.
Steffee, A. D., 1992, “The Steffee Artificial Disc,” Clinical Efficacy and Outcome in the Diagnosis and Treatment of Low Back Pain, Raven Press, Ltd., New York.
Thomas, J., Lowman, A., and Marcolongo, M., 2003, “Novel Associated Hydrogels for Nucleus Pulposus Replacement, “J. Biomed. Mater. Res., Part A, 67(4), pp. 1329–1337. [CrossRef]
Allen, M. J., Schoonmaker, J. E., Bauer, T. W., Williams, P. F., Higham, P. A., and Yuan, H. A., 2004, “Preclinical Evaluation of a Poly (Vinyl Alcohol) Hydrogel Implant as a Replacement for the Nucleus Pulposus,” Spine, 29(5), pp. 515–523. [CrossRef] [PubMed]
Thomas, J., Gomes, K., Lowman, A., and Marcolongo, M., 2004, “The Effect of Dehydration History on PVA/PVP Hydrogels for Nucleus Pulposus Replacement, “J. Biomed. Mater. Res., Part B, 69(2), pp. 135–140. [CrossRef]
Joshii, A., Fussell, G., Thomas, J., Hsuan, A., Lowman, A., Karduna, A., Vresilovic, E., and Marcolongo, M., 2006, “Functional Compressive Mechanics of a PVA/PVP Nucleus Pulposus Replacement,” Biomaterials, 27(2), pp. 176–184. [CrossRef] [PubMed]
Spenciner, D., Greene, D., Paiva, J., Palumbo, M., and Crisco, J., 2006, “The Multidirectional Bending Properties of the Human Lumbar Intervertebral Disc,” Spine J., 6(3), pp. 248–257. [CrossRef] [PubMed]
Spenciner, D. B., Paira, J., and Crisco, J., 2003, “Testing of Human Cadaveric Functional Spinal Units to the ASTM Draft Standard, “Standard Test Methods for Static and Dynamic Characterization of Spinal Artificial Discs,” ASTM Special Technical Publication, 1431, pp. 114–126.
Espinoza Orías, A. A., Malhotra, N. R., and Elliott, D. M., 2009, “Rat Disc Torsional Mechanics: Effect of Lumbar and Caudal Levels and Axial Compression Load,” Spine J., 9(3), pp. 204–209. [CrossRef] [PubMed]
Chuang, S.-Y., Odono, R. M., and Hedman, T. P., 2007, “Effects of Exogenous Crosslinking on in Vitro Tensile and Compressive Moduli of Lumbar Intervertebral Discs,” Clin. Biomech., 22(1), pp. 14–20. [CrossRef]
Wilke, H. J., Neef, P., Caimi, M., Hoogland, T., and Claes, L. E., 1999, “New in Vivo Measurements of Pressures in the Intervertebral Disc in Daily Life,” Spine, 24(8), pp. 755–762. [CrossRef] [PubMed]
Brinckmann, P., and Grootenboer, H., 1991, “Change of Disc Height, Radial Disc Bulge, and Intradiscal Pressure From Discectomy. An in Vitro Investigation on Human Lumbar Discs,” Spine, 16(6), pp. 641–646. [CrossRef] [PubMed]
Goel, V., Nishiyama, K., Weinstein, J., and Liu, Y., 1986, “Mechanical Properties of Lumbar Spinal Motion Segments as Affected by Partial Disc Removal,” Spine, 11(10), pp. 1008–1012. [CrossRef] [PubMed]
Markolf, K., and Morris, J., 1974, “The Structural Components of the Intervertebral Disc. A Study of Their Contributions to the Ability of the Disc to Withstand Compressive Forces, “The J. Bone Jt. Surg., Am. Vol., 56(4), pp. 675–687.
Andersson, G. B., and Schultz, A. B., 1979, “Effects of Fluid Injection on Mechanical Properties of Intervertebral Discs,” J. Biomech., 12(6), pp. 453–458. [CrossRef] [PubMed]
Ranu, H. S., 1993, “Multipoint Determination of Pressure-Volume Curves in Human Intervertebral Discs,” Ann. Rheum. Dis., 52(2), pp. 142–146. [CrossRef] [PubMed]
Zhao, F., Pollintine, P., Hole, B. D., Dolan, P., and Adams, M. A., 2005, “Discogenic Origins of Spinal Instability,” Spine, 30(23), pp. 2621–2630. [CrossRef] [PubMed]
Langrana, N., Edwards, W., and Sharma, M., 1996, “Biomechanical Analyses of Loads on the Lumbar Spine,” The Lumbar Spine, W.B. Saunders Company, Washington, DC.
Goel, V., Goyal, S., Clark, C., Nishiyama, K., and Nye, T., 1985, “Kinematics of the Whole Lumbar Spine: Effect of Discectomy,” Spine, 10(6), pp. 543–554. [CrossRef] [PubMed]


Grahic Jump Location
Fig. 1

Schematic of experimental protocol for partial denucleation experimental group

Grahic Jump Location
Fig. 2

Schematic of experimental protocol for nucleus augmentation group

Grahic Jump Location
Fig. 3

IVDs were denucleated using the Nucleotome (Clarus-Medical, Minneapolis, MN) in 5 min increments (until 20 min) then implanted with some volume of hydrogel nucleus replacement to restore to the intact disk height (DH ± 0.9%) and 5% above the intact disk height (+5DH ± 1.5%). There is a nonlinear implantation of material with a 17.5 and 7.8 min time constant, respectively. A third data set represents the augmented samples that were restored to 5% above intact disk height (+5%DH: Augmented). Average implant volumes are depicted with corresponding standard error means.

Grahic Jump Location
Fig. 4

IVDs were denucleated at time steps (5, 10, 15, and 20 min) then injected with some volume of hydrogel implant to restore to initial disk height. Percentage volume implanted versus (a) disk height normalized to intact and (b) change of pressure from intact were both fit by the method of least squares for: (i) the specimens after 20 min of denucleation and (ii) a representative anterior column unit at four time points.

Grahic Jump Location
Fig. 5

Normalized (a) NZ, tROM, and cROM and (b) stiffness for partially denucleated specimens when injected with implant to (i) 5% over intact disk height and (ii) intact disk height. (Average values are depicted with corresponding standard error means. p < 0.05: *statistically different from intact, +statistically different from 20 min of denucleation, @statistically different from 15 and 20 min of denucleation).

Grahic Jump Location
Fig. 6

Intact IVDs were augmented by adding some percentage of hydrogel into the nucleus pulposus. Percentage volume implanted versus (a) percentage disk height (normalized to intact) and (b) percentage pressure (normalized to intact) were both fit by the method of least squares.

Grahic Jump Location
Fig. 7

(a) Normalized NZ, tROM and cROM for augmented specimens. (b) Normalized stiffness for augmented specimens. (Average values are depicted with corresponding standard error means. p < 0.05: *statistically different from intact, +statistically different from +2.5%DH implantation).

Grahic Jump Location
Fig. 8

Comparison of augmented and denucleated states when restored to 105% of the intact disk height for normalized (a) NZ, tROM, and cROM and (b) stiffness. (Average values are depicted with corresponding standard error means. p < 0.05: *statistically different from intact, +statistically different from augmented implantation).



Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In