77SProceedings of the NASS 23rd Annual Meeting / The Spine Journal 8 (2008) 1S–191S

instrumentation. 15 patients had previous cervical cages, 2 had cage-plates,

15 patients had previous anterior cervical plates, one had a prior arthro-

plasty device with HO, and 4 patients had PMMA which required revision.

Despite the complicated nature of the presenting pathology, the Porous

Coated Motion Cervical prosthesis successfully restored some element

of cervical lordosis and restored stability to the cervical segments. The pro-

cedure preserved 9.4 degrees of flexion–extension mobility. The PCM ap-

peared to work well in these revision cases. This is the largest reported

series to date of cervical arthroplasties for adjacent level pathology and

the results at mid-level follow up thusfar are encouraging

FDA DEVICE/DRUG STATUS: PCM: Investigational/Not approved.

doi:10.1016/j.spinee.2008.06.180

149. Spine Implant Cost Containment: A Survey of Attending Spine

Surgeons

Matthew DiPaola, MD1, Christian DiPaola, MD2, Alexander Vaccaro, MD,

PhD1, Glenn Rechtine, MD2, Todd Albert, MD1; 1Thomas Jefferson

University, Philadelphia, PA, USA; 2Rochester, NY, USA

BACKGROUND CONTEXT: Inflation beating yearly rises in healthcare

costs over the last few years have prompted administrators to examine

healthcare expenditures more closely. Implants have been shown to repre-

sent a substantial portion of the overall expense incurred by the hospitals

that treat orthopedic patients. Studies have examined cost containment

strategies by hospitals for orthopedic implants. Most have looked at this

issue in the context of joint arthroplasty. Gainsharing has been proposed

as a potential method of reining in costs by more closely aligning provider

incentives with the healthcare system. Historically, the common denomina-

tor of all successful implant cost containment strategies has hinged on ac-

tive surgeon participation. While regulated tightly, certain gainsharing

arrangements may prove beneficial to enlisting the help of surgeons in im-

plant cost containment.

PURPOSE: To examine the attitudes of attending spine surgeons with re-

gard to issue of cost containment of spine implants. To attempt to create

a consensus regarding ethical and effective potential incentives that would

invite the spine surgeon to become an active participant in the cost contain-

ment process.

STUDY DESIGN/ SETTING: Survey study of attending spine surgeons.

PATIENT SAMPLE: none.

OUTCOME MEASURES: A survey was developed which consisted of 10

questions and 7 scenarios. The questions quantified the spine surgeon’s prac-

tice and experience with industry and negotiation of implant costs. The scenar-

ios examined the surgeon on a series of hypothetical situations which might be

presented to him/her as a means of enlisting his/her participation in a cost con-

tainment program. For each of these scenarios the surgeon had to answer sep-

arately whether the scenario was ‘‘ethical’’ and ‘‘effective’’ or not.

METHODS: Surveys were given to attending orthopedic surgeons and

neurosurgeons that identified themselves as spine surgeons per question

1 of the survey at a national spine meeting. All surveys were collected

anonymously and the results tabulated in a spreadsheet.

RESULTS: 35 of 69 surveys (51%) were completed. 17 and 18 surgeons

identified themselves as orthopedic spine surgeons and neurosurgeons re-

spectively. 80% of participants reported performingO100 spine cases per

year and 74% reported using instrumentation in over half of their cases.

Nearly half of the surgeons reported having at least some industry affiliation.

While only 26% of respondents stated that they had helped negotiate implant

prices for their hospitals in the past, 64% stated that they would be interested

if provided with more incentive to do so. Only 22% of respondents felt that

helping the hospital negotiate down implant prices would impair their rela-

tionship with industry and this was not highly correlated with an existing in-

dustry relationship. When given a hypothetical scenario, about 65% of

respondents felt that it was ethically appropriate for hospitals to place nego-

tiated implant cost savings into items such as more OR rooms, nurses or gen-

eral medical research. 85% felt that it was unethical for funds to go directly to

the participating surgeon’s research fund. Responses varied widely regarding

how effective each of these methods would be.

CONCLUSIONS: Surgeons are integral to the implant cost containment

process. Currently a gap exists between the number of spine surgeons that

help negotiate costs and those that may be incentivised to do so.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.181

Friday, October 17, 20084:20–5:20 PM

Special Interest Paper Presentation 1:Interventions

150. Investigation of Outcome of Injections for Synovial Cysts Yields

Different Results from Retrospective Chart Review and Prospective

Study: Why Spine Research Should Avoid Retrospective Chart

Reviews

Carolyn Schwartz, ScD, Julia Martha, BS, James Hill, MD, David Kim,

MD; New England Baptist Hospital, Boston, MA, USA

BACKGROUND CONTEXT: Lumbar synovial cysts are benign degener-

ative abnormalities of the lumbar spine and can lead to neurogenic claudi-

cation or sciatica if associated with stenosis or nerve root compression.

Previous reports have suggested epidural steroid injection or surgical exci-

sion as reasonable treatment alternatives. Attempted percutaneous cyst

rupture is occasionally performed, but there has been no systematic eval-

uation of this treatment option.

PURPOSE: To evaluate the success of injection treatment for lumbar cysts

with attempted cyst rupture.

STUDY DESIGN/ SETTING: (a) Retrospective cohort study based on

medical chart review and (b) prospective cross-sectional study by tele-

phone and mail.

PATIENT SAMPLE: From 1999–2005, 103 patients were identified who

were treated for lumbar facet joint synovial cysts with fluoroscopically-

guided corticosteroid facet joint injection and attempted cyst rupture. Med-

ical chart review was performed in October 2006 and the prospective study

was implemented in February 2007.

OUTCOME MEASURES: Time to surgical intervention (in both study de-

signs) and pre-treatment and post-treatment pain (Numerical Rating Scale

items) and Oswestry Disability Index scores (in prospective study only) were

collected along with details of subsequent treatment interventions.

METHODS: Multiple patient-specific clinical factors were analyzed in

terms of risk for surgical intervention using Cox Proportional Hazards

modeling and logistic regression modeling.

RESULTS: The chart review and prospective studies yielded different re-

sults. The prospective study identified several inaccuracies in the chart re-

view data, e.g., cyst status, age, level. The chart review also indicated

a significant association among successful cyst rupture, spinal level, and

treatment success such that successful rupture of L5-S1 level synovial cysts

appeared to lead to a significantly lower need for subsequent surgery (Hazard

ratio50.29, p!0.006). The prospective study did not confirm this level-by-

rupture interaction and found that cyst rupture had no impact on risk of sur-

gery or time to surgery. Fifty-five patients (54%) required subsequent surgery

over a period averaging 8.4 months due to inadequate symptom relief. All pa-

tients reported significant improvement in back pain, leg pain and disability

at 3.2 years post-injection, regardless of their subsequent treatment course

(p!0.0001 in all groups). The Cox model revealed that requiring two or more

injections (OR53.29, p!0.002, 95%CI51.54-7.07) and reporting higher

pretreatment disability (OR51.83, p!0.04, 95% CI51.04-3.23) are associ-

ated with a higher risk of having surgery.

78S Proceedings of the NASS 23rd Annual Meeting / The Spine Journal 8 (2008) 1S–191S

CONCLUSIONS: This study presents the largest clinical series of nonsur-

gical treatment for lumbar facet joint synovial cysts and documents disparate

findings from chart review and prospective designs. Whereas the chart re-

view suggested an association between level and rupture success, the pro-

spective study found that attempted cyst rupture did not appear to have

added benefit. It did, however, suggest that lumbar facet joint steroid injec-

tion may prevent surgery in half of treated patients. The prospective study

further suggests that patients requiring multiple injections and patients with

greater pretreatment disability are more likely to require surgical treatment.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.183

151. Are Electrodiagnostic Study Findings Related to Patient’s

Response to ESI?

Jason Marchetti, MD1, Sunita Verma-Kurvari, PhD2, Donna Ohnmeiss,

PhD2, Nayan Patel, MD1, Sharon Gibbs, MD1, Craig Lankford, MD1;1Texas Back Institute, Plano, TX, USA; 2Texas Back Institute Research

Foundation, Plano, TX, USA

BACKGROUND CONTEXT: Mechanical compression or chemical irri-

tation of the nerve roots are believed to be the primary reasons for neuro-

genic pain caused by spinal sources. Epidural steroid injections (ESIs)

minimize pain caused by nerve root irritation and are one of the most com-

mon procedures performed for the management of chronic pain in the

United States. While there is strong evidence for short term relief with

ESI in the treatment of lumbar pain, few studies have been done to identify

patient factors that are associated with good outcome upon ESI. Electro-

myography (EMG) is a commonly used procedure to investigate paraspinal

and peripheral muscle activity and to assess the condition/integrity of the

neuronal connection. The usefulness of EMG as a predictive tool for suc-

cess of ESI is poorly understood.

PURPOSE: The purpose of this study was to determine if ESI results are

related to EMG findings in patients with radicular symptoms or clincal

findings consistent with radiculopathy.

STUDY DESIGN/ SETTING: This is a retrospective chart review of pa-

tients treated at a multi-site clinic by several physicians. Electrodiagnostic

studies were conducted by board certified Physiatrists.

PATIENT SAMPLE: All patients that had needle electromyography (with

or without nerve conduction testing) prior to epidural steroid injection be-

tween 2005 and 2007 were identified.

OUTCOME MEASURES: The clinical outcome measures were visual

analog scale scores (VAS) assessing leg and back pain.

METHODS: Leg and back VAS scores from patients that had EMG followed

by an ESI were collected. Post-ESI data was collected at one month. In some

patients VAS results were available after 2nd or 3rd epidural injection. Other

data recorded included gender, birth year, prior back surgery, injection type

and number of days post-ESI. Evidence of radiculopathy on EMG reports

was classified as positive, normal or equivocal. Positive findings were qualified

as being acute, chronic or both (mixed). Definitions used, are typical of those

from most electrodiagnostic texts. ESI relief was defined as $50% improve-

ment in the VAS score assessing leg pain after the injection.

RESULTS: Data from 54 patients were analyzed. Most of the patients

were diagnosed with radicular syndrome and/or spinal stenosis, spondylo-

listhesis or spondylosis. A majority of the patients had normal EMG read-

ings (n5 37, 68%) suggesting that leg complaints are either due to

‘‘referred pain’’ or chemical radiculitis. A smaller number had positive

EMG readings (n59, 17%) implying these patients suffer from a more se-

vere lesion that is causing nerve compression and axonal damage. EMG

readings for 15% (n58) patients were equivocal. There were no significant

differences in the percentages of patients expereincing a positive response

to the ESI with respect to EMG findings. Forty percent of patients (15/37)

with normal EMGs, 33% of patients (3/9) with positive EMGs and 25%

patients (2/8) with equivocal EMGs had relief after ESI.

CONCLUSIONS: Results of this retrospective study show that a similar

proportion of patients have a good outcome following ESI irrespective

of the EMG findings. These results refute the concept that ESI is not indi-

cated in patients with negative EMG findings.

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

any applicable devices or drugs.

doi:10.1016/j.spinee.2008.06.184

152. Plasma Disc Decompression Compared to Conservative Care

for Treating Symptomatic Contained Cervical Disc Protrusion: One

Year Results from a Prospective Randomized Controlled Study

Alessandro Cesaroni, MD, Pier Vittorio Nardi, MD; Policlinico Casilino,

U.O.C. Neurochirurgia, Roma, Italy

BACKGROUND CONTEXT: Plasma disc decompression (PDD) may

provide a good treatment option when patients with symptomatic con-

tained cervical disc herniation do not respond to conservative care.

PURPOSE: To compare the effectiveness of PDD to continuing conserva-

tive care (CC) for treating symptomatic contained cervical disc herniation.

STUDY DESIGN/ SETTING: Prospective, randomized, controlled clini-

cal study.

PATIENT SAMPLE: The study group consisted of 115 patients between

the ages of 18 and 75 years old who had neck/arm pain (visual analogue

scale (VAS) score 50 points) not alleviated after 30 days CC care and as-

sociated with a single-level cervical disc herniation as evidenced by posi-

tive diagnostic nerve block and by imaging showing focal protrusion !1/3

the diameter of the spinal canal.

OUTCOME MEASURES: Visual Analogue Scale (VAS) score for neck/

arm pain, Neck Disability Index (NDI), SF-36 questionnaire collected at 6

weeks, 3 months, 6 months, and 12 months.

METHODS: A priori sample size estimation, using a common standard de-

viation of 25 points on a 100-point VAS for pain and setting type I error rate

at 5%, suggested that a sample size of 44 subjects in each group would have

80% power to detect a difference in means of 15 VAS points at 6 months

after PDD. Patients were randomly assigned to receive PDD (n562) or con-

tinuing CC (n553) consisting of transcutaneous electrical stimulation, pro-

gressive neck mobilization with gradual reduction of collar use, postural

rehabilitation, analgesics, and/or NSAIDS. The PDD was performed using

a plasma ablation device (DC SpineWand; ArthroCare Corporation, Austin,

TX). Group-wise comparisons were conducted using the Student’s t-test,

Mann-Whitney U test, Chi-square test and Fisher’s exact test; general linear

model-repeated measures was used to evaluate longitudinal change.

RESULTS: Age (45611 vs 47611; p50.25), gender (male: 37% vs 48%;

p50.237), and baseline scores for pain (73613 vs 75612; p50.545), NDI

(2169 vs 23611; p50.369), and SF-36 physical components summary

(PCS: 3569 vs 3468; p50.256), did not differ significantly between

PDD and CC patients, respectively. The PDD group showed significantly

greater reduction in neck pain than the CC group at 6 weeks, 3 months,

6 months and 1 year, respectively (PDD vs CC: �47621 vs �16614,

�53621 vs �31618, �56621 vs �41618; �66619 vs �37621;

p!0.001). Significantly more PDD patients showed O525 point reduction

in pain VAS scores compared to CC patients at 6 weeks (84% vs 23%;

p!0.001), 3 months (86% vs 66%; p50.014), 6 months (87% vs 81;

p50.380) and 1 year (95% vs 69%; p!0.001). The PDD group also had

significantly greater improvement in NDI scores than the CC patients(6

weeks, 968 vs 564, 3 months, 11610 vs 1066, 6 months 13611 vs

1367, 1 year 1669 vs 13610; p!0.001). At 6 weeks, 32% of PDD pa-

tients demonstrated O510.5-point improvement in NDI score compared

to 6% of CC patients (p!0.001). At 1 year, 74% of PDD patients demon-

strated O510.5-point improvement in NDI score compared to 53% of CC

patients (p50.017). SF-36 PCS for the PDD group showed significant im-

provement at 6 weeks (44610 vs 3868; p!0.001), 3 months (47610 vs

4269; p50.001), 6 months (49611 vs 4668; p50.031) and 1 year

(5369 vs 46610; p!0.001) compared to the CC group.