42S Proceedings of the NASS 26th Annual Meeting / The Spine Journal 11 (2011) 1S–173S

CONCLUSIONS: Discography is used extensively in the evaluation of

low back pain. Since the lifetime prevalence of disc degeneration and

low back pain is high (80% in the general population), many patients

may undergo this procedure. Data presented here showed that cells ex-

posed in vitro to a radiocontrast agent with adjustments for osmolality have

significantly reduced proliferation, increased cell death, and increased pro-

grammed cell death (apoptosis). In light of the well-recognized age- and

degeneration-related decrease in disc cell numbers, it is possible that radio-

contrast exposure may be contributing significantly to disc cell loss with

subsequent progression of disc degeneration. Findings presented here

provide a plausible cell-based explanation for the previously reported disc

degeneration in patients receiving discography contrast solutions.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

doi: 10.1016/j.spinee.2011.08.110

79. Intervertebral Disc-Derived Stem Cells: Implications for

Regenerative Medicine and Neural Repair

Mark Erwin, DC, PhD1, Michael Fehlings, MD, PhD, FRCSC2; 1Toronto,

ON, Canada; 2Toronto Western Hospital, Toronto, ON, Canada

BACKGROUND CONTEXT: Neurological impairment due to spinal

cord or nerve root damage may occur acutely in the case of trauma, grad-

ually over time secondary to tumor growth or associated with advanced

degenerative changes in the spine such as is the case with DDD. The enor-

mous challenges posed by DDD and spinal nerve and spinal cord injury

(SCI) share a common thread: the loss of viable cells. Any biological agent

introduced as a therapeutic intervention would require sufficient numbers

of viable cells with functional receptors upon which to act. In order to sur-

mount these challenges there has been considerable interest in the develop-

ment of cell-based therapies for the treatment of disc disease, SCI and

nerve injury through which viable cells might be re-introduced to these tis-

sues in order effect repair. Stem cells have become an area of significant

interest with respect to possible cellular replacement strategies for neural

repair; specifically including stem cells that are capable of differentiating

into specific neural cells. With respect to potential repair strategies consid-

erable interest has been expressed over the past few years in the use of

human embryonic stem cells (hESC), adult human stem cells (aHSC)

and more recently induced pluripotential stem cells (iPS). However an im-

portant obstacle has been the proper choice of cells since some of them are

not readily available and transplants from other sources are plagued by

many problems including the ability of the cells to differentiate properly

and integrate into the spinal cord. Also, potential problems posed by the

use of induced pluripotential stem (iPS) cells including teratoma formation

of myc-containing iPS cells continue to raise significant concern about the

use of this source of cells. Some early attempts at tissue repair have been

attempted using murine ESCs and there are early clinical trials using hESC

cells for SCI. Here we demonstrate for the first time, that resident multi-

potent progenitor cells expressing classic ‘‘stemness’’ genes exist within

the NP ‘niche’ of the non-chondrodystrophic canine nucleus pulposus.

These nucleus pulposus progenitor cells (NPPCs) are multipotent cells that

can differentiate into multiple cell lineages in vitro such as adipocytes and

chondrocytic cells. We also demonstrate that NPPCs when injected into the

brain of the shiverer mouse (a compact myelin-deficient phenotype) also

form oligodendrocytes, neurons and astroglial cells and myelin basic

protein.

PURPOSE: To determine the differentiation capacity of non-chondrody-

strophic canine NPPCs in vitro, the in vivo capacity of NPPCs to differeni-

ate into various classes of neural cells.

STUDY DESIGN/SETTING: In vitro and and in vivo laboratory-based

study using acute non-chondrodystrophic canine lumbar spine interverte-

bral discs and new born shiverer mice.

PATIENT SAMPLE: No human patients, animal studies only as above.

OUTCOME MEASURES: Immunohistochemical analysis, qRT-PCR

gene expression analysis.

All referenced figures and tables will be available at the Annual Mee

METHODS: Dissection of non-chondrodystrophic canine lumbar inter-

vertebral discs, harvest of nucleus pulposus and expansion of multipotent

stem cells in suspension culture. In vitro differentiation into chondrogenic,

adipogenic, neurogenic and osteogenic pathways. In vivo transplantation

of GFP-transfected NPPCs into the brain of newborn shiverer mice fol-

lowed by sacrifice of the mice and 4% paraformaldehyde perfusion and im-

munohistochemical analysis of neural differentiation within the murine

brain.

RESULTS: Non-chondrodystrophic NPPCs are able to differentiate along

chondrogenic, adipogenic and neurogenic lineages in vitro but do not dem-

onstrate osteogenesis. NPPCs transplanted within the newborn shiverer

mouse brain demonstrate robust capacity to form neuron precursors (BIII

tubulin and NF200 staining), astroglial differentiation (GFAP staining) and

oligodendrocyte precursor formation (CNApase and myelin basic protein

staining). NPPCS demonstrate pluripotential genes CD133, Sox2, Oct3/

4, Nanog, NCAM and Nestin.

CONCLUSIONS: The canine intervertebral disc nucleus pulposus con-

tains cells that demonstrate multipotentcy and are capable of differentiat-

ing into chondrogenic, adipogenic and neurogenic lineage in vitro but fail

to differentiate along the osteogenic lineage. NPPCs injected into the brain

of the shiverer mouse are capable of differentiating into multiple neural

cell precursors indicative of neuron, astroglial and oligodendroctye pheno-

types with clear evidence of myelin formation. The results of this study

suggest that the intervertebral disc may be a source of multi-potent progen-

itor cells that could be useful in regenerative medicine and neural repair

applications.

FDA DEVICE/DRUG STATUS: This abstract does not discuss or include

any applicable devices or drugs.

doi: 10.1016/j.spinee.2011.08.111

80. Early Postoperative Analgesic Effects of Single Epidural

Ropivacaine Injection Before Surgery in Posterior Lumbar Spinal

Fusion: A Randomized Controlled Trial

Song Kwang Sup, MD, PhD1, Jae Jun Yang, MD2; 1Chung-Ang University,

College of Medicine, Seoul, South Korea; 2Chung-Ang University Yong-

San Hospital, Seoul, South Korea

BACKGROUND CONTEXT: Postoperative pain managements follow-

ing spine surgery have been the main concern. Despite ropivacain has

a suitable characteristics for preemptive epidural anesthesia, the clinical

trial has not yet been reported.

PURPOSE: To investigate the preemptive analgesic effects of single epi-

dural ropivacaine injection on the intensity of postoperative pain and re-

ducing of the parental opioid requirements following posterior one level

lumbar fusion surgery.

STUDY DESIGN/SETTING: A prospective, randomized, controlled

trial.

PATIENT SAMPLE: Inclusion criteria were a planned one-level posterior

lumbar interbody fusion with decompression for severe stenosis and/or

spondylolithesis accompanied by segmental instability. Excluded from

the study were patients who weighed less than 45 kg or more than

100 kg, had severe underlying respiratory, renal or hepatic disease, or

had allergy history to local anaesthetics.

OUTCOME MEASURES: Preoperative parameters: age, gender, Ameir-

can Society of Anethesiologists physical status, preoperative VAS for back

and Oswestry Disbility Index were recorded and duration of operation

from skin incision to closure. After surgery, VAS (0–10) and the frequency

at which patients pushed the button of PCA (FPB) and analgesic consump-

tions were assessed.

METHODS: From between August 2008 and June 2010, Patients in group

C (control group) did not received any medication and those in group I (in-

stillation group) received epidural injection of 0.1% ropivacaine 10 ml,

20 min before skin incision at planed operative spine level in double blined

manner. To measure pain intensity, VAS (0–10) at 2, 4, 8, 12, 24, 48 hr

ting and will be included with the post-meeting online content.