49SProceedings of the NASS 22nd Annual Meeting / The Spine Journal 7 (2007) 1S–163S

II ossification, 3.1% as Class III ossification, and 2.0% as Class IVossifica-

tion. Class I patients, by definition, do not experience any change in range of

motion. The mean flexion/extension range of motion for patients with Grade

II or Grade III ossification was 6.4� at 24 months post-operatively, with

a range of 2.3� to 16.0�. This is comparable to the 8.6� mean flexion/exten-

sion range of motion with a range of 0.6� to 24.1� at 24 months post-opera-

tively for the entire ProDisc�-C group. In all but one ProDisc�-C patient,

the radiographic finding of anterior ossification was not associated with

any adverse events. When patients with Class II or higher HO were analyzed

against the remaining ProDisc-C patient population with regards to NDI,

VAS Arm Pain and Intensity, VAS Neck Pain and Intensity, and VAS Satis-

faction, there was no statistical difference in outcomes.

CONCLUSIONS: Although HO may exist on radiographs, the clinical

significance of such findings is inconsequential. Patients were not experi-

encing greater adverse events or pain associated with the HO. Moreover,

patients were not experiencing statistically different range of motion as

a result of the formation in comparison to remaining population except

in the 2 patients with Class IV. HO formation in this study does not appear

to be device-related but more a result of surgical technique. The use of

NSAIDs post-operatively may significantly reduce the formation of HO.

FDA DEVICE/DRUG STATUS: ProDisc-C Investigational/ Not

approved.

doi: 10.1016/j.spinee.2007.07.117

99. Measuring Cervical Arthroplasty Outcomes: Comparison of SF-

36 Improvements in Cervical Disc Replacement, Cervical Fusion,

TKA and THA

Thomas Puschak, MD1, Paul Anderson, MD2, Rick Sasso, MD3;1Panorama Orthopedics and Spine Center, Golden, CO, USA; 2University

of Wisconsin-Madison, Madison, WI, USA; 3Indianapolis, IN, USA

BACKGROUND CONTEXT: Clinical improvement in hip and knee ar-

throplasty is well known and accepted while outcomes of disc arthroplasty

are as yet unknown. The SF-36 allows comparison across various disease

states thus allowing comparisons between different forms of arthroplasty.

If disc arthroplasty can show similar improvement, greater acceptance

by surgeons, patients and other parties may occur.

PURPOSE: This study compares SF-36 results of last 5 years publications

of TKA and THA to outcomes of Bryan and Prestige discs and anterior

cervical fusion controls in the FDA pivotal study to see if cervical disc ar-

throplasty outcomes are similar to outcomes in hip and knee replacement.

STUDY DESIGN/SETTING: The North American literature for hip and

knee arthroplasty was searched from 1999 to 2006 for studies which

included preoperative and postoperative SF-36. Means and standard devi-

ations for pre and postoperative SF-36 scores were calculated and com-

pared to the SF-36 scores for Bryan and Prestige Discs and anterior

cervical fusion controls.

PATIENT SAMPLE: Cervical disc replacement patients and anterior

fusion controls came from the US FDA pivotal studies and included

242 Bryan Discs, 276 Prestige Discs and 484 anterior cervical fusions.

OUTCOME MEASURES: The preoperative and one-year postoperative

SF-36 scores for the Bryan and Prestige ST disc and fusion controls were

obtained from the FDA pivotal study. Weighted average SF-36 scores were

calculated for the hip and knee arthroplasty studies.

METHODS: The MEDLINE database was searched for prospective stud-

ies reporting SF-36 scores for hip and knee arthroplasty between January

1999 and August 2006. Twenty-five manuscripts met the inclusion criteria

of a cohort greater than fifty patients, pre and postoperative SF-36 scores

reported, at least one-year follow-up and only primary operations. The pre-

operative and one-year SF-36 scores for the Bryan and Prestige ST disc US

pivotal studies comparing cervical disc replacement to anterior fusion with

plate and allograft were obtained. Weighted average SF-36 scores for the

PCS, MCS (physical and mental summary scores) and individual domains

were calculated for the hip and knee arthroplasty studies and compared to

the same outcomes for cervical fusion and disc arthroplasty patients.

RESULTS: The literature review studies assessed 2271 hip and 1943 knee

patients. The pivotal studies had 242 Bryan Discs, 276 Prestige Discs and

484 fusion patients. PCS scores improved significantly from baseline by 12

points for hip arthroplasty and 10 points for knee arthroplasty. Cervical

fusion and arthroplasty PCS scores both improved 13.5 points postopera-

tively and were statistically significant. Cervical fusion and disc arthro-

plasty patients had 8 point MCS improvements. Furthermore hip and

knee patients had significantly less intial mental health abnormality com-

pared cervical patients. The changes in PCS in the cervical spine patients

were not only greater than hip and knee arthroplasty but occurred in

patients with worse mental health.

CONCLUSIONS: The SF-36 has been shown to be a reliable outcomes

measure in the general population. Clinical improvement from hip and

knee arthroplasty is well documented and accepted. SF-36 improvement

in both mental and physical health scores as a result of cervical disc arthro-

plasty or fusion is similar or greater than hip and knee arthroplasty.

FDA DEVICE/DRUG STATUS: Bryan Cervical Disc: Investigational/

Not approved; Prestige Cervical Disc Investigational/ Not approved.

doi: 10.1016/j.spinee.2007.07.118

Thursday, October 25, 20075:04–6:04 PM

Special Interest Poster Presentation 3: Deformity

100. The Impact of Peri-operative Complications on Clinical

Outcome in Adult Deformity Surgery

Steven Glassman, MD1, Chris Hamill, MD2, Keith Bridwell, MD3,

Frank Schwab, MD4, John Dimar, II, MD5, Thomas Lowe, MD6;1Leatherman Spine Center, Louisville, KY, USA; 2University at Buffalo,

NY, USA; 3Washington University in St. Louis, St. Louis, MO, USA;4Maimonides Medical Center, Brooklyn, NY, USA; 5University of

Louisville, Louisville, KY, USA; 6University of Colorado Health Sciences

Center, Wheat Ridge, CO, USA

BACKGROUND CONTEXT: As HRQOL measures become a standard

for determining clinical outcomes, correlation with historic benchmarks,

such as curve correction, sagittal balance, or the occurrence of a complica-

tion, must be clarified.

PURPOSE: The purpose of this study was to determine whether peri-

operative complications affect the HRQOL measures after adult spinal

deformity surgery.

STUDY DESIGN/SETTING: Prospective multi-center case control.

PATIENT SAMPLE: Patients from a prospective multi-center database

for adult spinal deformity.

OUTCOME MEASURES: SF-12, ODI, Numeric Rating Score (NRS) for

back and leg pain, and SRS-22.

METHODS: From a prospective multi-center database for adult spinal de-

formity, patients with major, minor or no complication were matched on

five parameters known to correlate with clinical outcome (age, primary di-

agnosis, pre-op SRS total score, distal fusion level, and sagittal balance at

one-year postoperative). Major complications included cord injury, DVT

and deep infection. Minor complications included CSF leak, skin problems

and seroma. 46 patients in each complication group were identified. The

SF-12, ODI, NRS for back and leg pain, and SRS-22 in the three groups

were compared.

RESULTS: For all outcome measures, significant improvement from base-

line to one year postoperative was observed in all three groups, except in

the SF-12 general health and role emotional subscales and SF-12 MCS.

Comparison between groups revealed no statistical differences at one year

post-operative for SRS-22, SF-12 PCS, ODI, or numeric pain scales. The

only significant interaction was for the SF-12 general health subscale at

one year postoperative. In the group with major complications, SF-12

50S Proceedings of the NASS 22nd Annual Meeting / The Spine Journal 7 (2007) 1S–163S

general health deteriorated by 2.1 points, compared to an improvement of

1.5 points in the group with no complications and an improvement of 4.2

points in the group with minor complications (major vs. minor p!0.05).

CONCLUSIONS: This study suggests that the impact of a minor compli-

cation on clinical outcome at one year following surgery is relatively lim-

ited. There were no differences in outcome between the group with minor

complications and the group without complications. For patients with ma-

jor complications, the was a significant deterioration in the SF-12 general

health subscale as compared to the patients with minor complications.

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

any applicable devices or drugs.

doi: 10.1016/j.spinee.2007.07.120

101. High Grade Spondylolisthesis Treated with Posterior

Decompression, Posterolateral Fusion and Fibular Dowel Grafting

Christopher G. Furey, MD1, George H. Thompson, MD1, Henry

H. Bohlman, MD1; 1Case Western Reserve University, Cleveland, OH, USA

BACKGROUND CONTEXT: High grade spondylolisthesis is a disabling

condition with a strong propensity for deformity progression. Spine fusion

can effectively relieve pain, improve function, and prevent deformity progres-

sion. However, debate exists as to the most effective and safe surgical technique.

PURPOSE: To study the long-term clinical and radiographic outcomes of

pedicatric patients with high grade spondylolisthesis treated with posterior

decompression, posterolateral fusion and fibular dowel strut graft.

STUDY DESIGN/SETTING: Retrospective clinical and radiographic

review.

PATIENT SAMPLE: Twenty-two pediatric patients underwent surgery.

Average age was 13.5 years (range 11–17 years). 5 patients had Meyerding

grade III spondylolisthesis, 12 had grade IV, and 5 had spondyloptosis.

Average follow-up was 8.6 years (range 3–17 years).

OUTCOME MEASURES: Questionnaires requesting each patient to de-

fine their relief of back and leg pain, improvement in quality of life,

achievement of pre-operative goals, and willingness to repeat the surgical

procedure. Meyerding slip grade, slip angle, sacral inclination, and sagital

balance were measured pre- and post-operatively. Posterolateral fusion

mass and fibular graft incorporation were determined with plain radio-

graphs. CT scan was employed if there was concern for pseudarthrosis.

METHODS: A posterior decompression was performed at the L5 level to

widely expose the L5 and S1 nerve roots . Under fluoroscopy, a cannulated

reamer created a channel from the posterior aspect of the S1 body across the

disc space into the L5 body. A fibular graft was impacted into position

within the channel. A standard posterolateral fusion was performed with il-

iac crest bone graft. Pedicle screw fixation was employed based on surgeon

discretion. No forceful attempt at deformity correction was undertaken.

RESULTS: Relief of back pain was good or excellent in 20 patients

(91%). Relief of leg pain was good or excellent in 22 patients (100%).

21 patients (95%) reported improvement in their quality of life post-oper-

atively. 21 patients (95%) felt their pre-operative expectations had been

met. 20 patients (91%) had a solid fusion at 6 months postoperatively. 2

patients (9%) had evidence of a pseudarthrosis. Slip angle improved from

pre-operative average of 32 degrees to post-op average of 16 degrees.

There was slightly greater improvement in slip angle and sacral inclination

in patients in whom pedicle screw fixation was employed, though this was

not significant. Deformity progression of a single grade (!25%) occurred

in 4 patients (18%), all of whom were uninstrumented and two of whom

had a pseudarthrosis. Transient L5 sensory neuropraxia occurred in 4 pa-

tients (18%). No motor deficits occurred. Three patients (14%) required

an additional surgery. Two patients (9%) with a pseudarthrosis required re-

vision fusion with instrumentation. One patient (5%), with a solid postero-

lateral fusion, had elective removal of painful instrumentation. Fracture of

a fibular dowel occurred in one patient (5%), who had a solid posterolateral

fusion and was asymptomatic.

CONCLUSIONS: High grade spondylolisthesis was effectively treated

with posterior decompression, posterolateral fusion, and fibular dowel

grafting. Pain relief and improved function were reliably achieved and

complication rates were low.

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

any applicable devices or drugs.

doi: 10.1016/j.spinee.2007.07.121

102. Incidence and Risk Factors of Neurological Deficits of Surgical

Correction for Scoliosis: Analysis of 1373 Cases at One Chinese

Institution

Qiu Yong1; 1Drum Tower Hospital, Nanjing University Medical School,

Nanjing, Jiangsu, China

BACKGROUND CONTEXT: A retrospective study was designed to an-

alyze the incidence of neurological deficits among 1373 patients with sco-

liosis undergoing surgical correction and investigate the risk factors at one

Chinese institution.

PURPOSE: Neurological deficit is one of the risks of surgical correction

of scoliosis. Although multi-center data analysis has been available, re-

ports of the incidence of the neurological deficits involving a large number

of cases at one institution are rare.

STUDY DESIGN/SETTING: A retrospective study was designed to an-

alyze the incidence of neurological deficits among 1373 patients with sco-

liosis undergoing surgical correction at one institution in the light of the

patients’ age, hyperkyphosis, etiology, surgical approach, Cobb’s angle,

and time of surgery.

PATIENT SAMPLE: Between 1998 and 2005 at the same institution,

1,373 patients with scoliosis undergoing surgical correction .

OUTCOME MEASURES: Among the 1,373 scoliosis patients admitted

between 1998 and 2005 at the same institution, the total incidence of neu-

rological deficits was 1.89%, and that of serious and mild ones was 0.51%

and 1.38% respectively.

METHODS: Statistical analysis of the neurological deficits were per-

formed in 1,373 scoliosis cases treated at one institution in the light of

the patients’ age, hyperkyphosis, etiology, surgical approach, Cobb’s an-

gle, and time of surgery (primary or revision surgery), and the incidence

of the deficits was calculated respectively.

RESULTS: The incidence of neurological deficits was 1.06% in AIS pa-

tients, significantly lower than that in patients with congenital scoliosis

(2.89%, P!0.05). The incidence was significantly higher in scoliosis pa-

tients with hyperkyphosis(O40�) than in those without hyperkyphosis

(3.32% vs 1.28%, P!0.05). The incidence was 3.43% for combined proce-

dures, significantly higher than that for single anterior (0.95%) or single

posterior (1.24%) procedure, but statistically, the difference was significant

only between combined and single posterior procedures (P!0.05). In pa-

tients with Cobb’s angle more than 90�, the incidence was 3.69%, signif-

icantly higher than that in those with an angle less than 90�(1.45%).

Compared with primary surgery, revision surgery increase the incidence

of the neurological deficits (1.68% vs 5.97%, P!0.05).

CONCLUSIONS: In surgical correction of scoliosis, the risk factors for

neurological deficits include congenital scoliosis, scoliosis with hyperky-

phosis, scoliosis correction by combined procedures, scoliosis with

a Cobb’s angle more than 90�, and a revision surgery.

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

any applicable devices or drugs.

doi: 10.1016/j.spinee.2007.07.122

103. Brachial Plexus Palsy Caused by Halo Traction before Posterior

Correction in Severe Scoliosis

Bangping Qian, MD1; 1Drum Tower Hospital, Nanjing University Medical

School, Nanjing, Jiangsu, China

BACKGROUND CONTEXT: Halo-traction has been used as one of the

standard adjunctive therapy measures prior to reconstructive surgery in the