134S Proceedings of the NASS 25th Annual Meeting / The Spine Journal 10 (2010) 1S–149S

PURPOSE: We hypothesize that cervical spine geometric parameters dif-

fer between asymptomatic and myelopathic patients, and that laminar roof

pitch is more accurate than Pavlov-Torg ratio, Matsuura ratio, sagittal

anterior-posterior canal diameter and transverse medial-lateral canal diam-

eter in identifying myelopathic patients.

STUDY DESIGN/SETTING: This is a retrospective study.

PATIENT SAMPLE: We identified two cohorts: (1) asymptomatic con-

trols and (2) symptomatic patients with myelopathy or both myelopathy

and radiculopathy. Control patients were from a trauma registry and did

not have cervical trauma, prior surgery or signs and symptoms of myelop-

athy. Myelopathic patients all had correlative compression on imaging, and

Nurick score improved postoperatively.

OUTCOME MEASURES: Sagittal measurements included (1) anterior-

posterior (AP) canal diameter at mid-vertebra and (2) at disc level; (3)

AP vertebral body diameter; (4) Pavlov-Torg ratio and (5) disc-level Pav-

lov-Torg ratio. Axial measurements included (1) laminar roof pitch angle

(LRP) and (2) Matsuura ratio, which is AP canal diameter divided by the

medial-lateral (ML) canal diameter at mid-pedicle. Mixed parameters are

detailed in Table 1.

METHODS: A two-way ANOVA using group and vertebral level as

factors was followed by Tukey’s posthoc procedure. Receiver-operator

analysis was used to study sensitivity and specificity.

RESULTS: Eighteen control patients, average age 63.8613.4 years, and

nineteen symptomatic patients, average age 60.3611 years, were identified.

Neither LRP, Pavlov-Torg ratio nor Matsuura ratio differed between groups

(all pO0.05). Transverse ML canal diameter, mid-vertebral and disc-level

sagittal AP canal diameter differed between groups (p!0.05; Fig1). Mixed

sum, a surrogate for canal perimeter, and mixed area at mid-vertebral and

disc levels also differed (p!0.05). Transverse ML canal diameter and the

mixed sum of transverse ML and sagittal AP canal diameters had the best

combined sensitivities and specificities (Fig2). Transverse ML diameter less

than 23.5 mmproduced 82% sensitivity and 68% specificity.Mixed sum had

79% sensitivity and 78% specificity with a 36 mm threshold.

CONCLUSIONS: Transverse ML canal diameter had the best combined

sensitivity and specificity, despite studying spondylotic patients. Medial-

lateral reserve at the pedicle level may be more important than disc-level

arthrosis in spondylotic myelopathy. The cross-sectional area at the mid-

vertebral body and at the disc differed between control and symptomatic

patients. This contrasts with prior findings that the canal area did not differ

between normal patients and those who experienced cervical SCI. These

data emphasize that risk factors for myelopathy and acute SCI may differ.

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

any applicable devices or drugs.

doi: 10.1016/j.spinee.2010.07.345

P70. 24-Month Prospective Results of a New Cervical Staple in

Anterior Cervical Discectomy and Fusion: Quality of Life and

Fusion

Vincent Fiere, MD1, Pierre Bernard2, Olivier Ricart3, Fahed Zairi, MD4;1Centre Orthopedique Santy, Lyon, France; 2Centre Aquitain du Dos,

Pessac, France; 3Clinique Ambroise Pare, Thionville, France; 4Chru Roger

Salengro, Lille, France

BACKGROUND CONTEXT: Anterior cervical discectomy and fusion

(ACDF) is currently by far the most used technique in cervical surgery.

Arthrodesis is obtained with a bone graft or an intersomatic spacer gener-

ally secured using a screwed osteosynthesis plate. Implantation of cervical

plate is time consuming and exposes the patient to additional adverse

events which may require more surgery. To maintain the position of the in-

tersomatic spacer and to increase bone fusion while maintaining dynamic

compression, a cervical compressive staple has been developed.

PURPOSE: To evaluate clinical and radiological results of a new cervical

compressive staple used to stabilize a PEEK spacer in ACDF procedure.

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

STUDY DESIGN/SETTING: Prospective multicenter non comparative

study.

PATIENT SAMPLE: Patient inclusion criteria consisted of single level

cervical disc herniation (at C4-Th1 levels), without previous surgery and

with cervicobrachial neuralgias which had not responded to conservative

treatment. Eighty-two patients from 5 centers were prospectively included

in the study.

OUTCOME MEASURES: Preoperative and Postoperative neurological

status was evaluated by the Neck Disability Index (NDI) and Visual ana-

logic pain scales (VAS) and general health status by the SF-12. Functional

outcome (odom criteria) and patient satisfaction were also considered.

Neck disability success was based on the postoperative NDI score being

better than pre-operative score by at least 15 points (if preoperative score

O30 points) or at least 50% (if preoperative score!30 points). Arm and

Neck pain success was defined by at least a 2 point improvement in pain

score (in patients with a preoperative score $4) or maintenance of the pre-

operative score in patients with preoperative score of!4 or less. Radio-

graphic examinations including dynamic flexion-extension and lateral

films were used to assess fusion, mobility or signs of pseudarthrosis.

METHODS: All patients were treated with an anterior cervical discec-

tomy and fusion using a Peek spacer prefilled with bone substitute (trical-

cium phosphate) and secured by the cervical compressive staple. At

follow-up, each patient has completed self-questionnaires (NDI, VAS,

SF-12 and satisfaction), radiographic control and a clinical evaluation were

done. X-rays were reviewed by two independent observers.

RESULTS: The average operating timewas 35 min (range 30 to 40), and the

average stay at hospital was 1.5 days (range 1 to 2 days). 90% of the patients

had a solid fusion.MeanNDI score (range)was significantly improvedby20.2

(0–43) preoperatively to 6.6 (0–34) at last follow-up. 87% of the patients re-

ported a NDI success. Mean Neck and Arm pain were significantly improved

by 6.1 (0–10) and 7.0 (0–10) to 1.8 (0–8.6) and 2.2 (0–9.5), respectively at last

follow-up. 90% and 88% of the patients reported a Neck pain and Arm Pain

success respectively. Mean SF-12 Physical Component Summary (PCS) and

Mental Component Summary (MCS) scores were significantly improved by

37.0 and 38.4 respectively to 48.9 and 50.9 at last follow-up. 91% of the

patients are completely satisfied or satisfied by the surgery and 89% had

a successful functional outcome at last follow-up. On the 82 patients, 1 had

a preoperative vascular lesion without consequences for the patient, 1 had ex-

perimented a transient dysphagiawhichwere relieved at 2 month follow-up. 3

patients had experimented a hardware-related events (2 breakage and 1 minor

back-out) without clinical consequences and without revision: all patients re-

ported no complains andX-rays showed solid fusion. 2 revision surgerieswere

required for pseudarthrosis and 2 additional surgeries for a degeneration at the

superior adjacent level.

CONCLUSIONS: Patients presented solid fusion with significant pain re-

lief and improvement of their quality of life. Compared to previous data,

success rate and occurrence of complication were similar. The staple seems

to provide a safe and effective new way to secure an intersomatic spacer

with a reduced surgical time.

FDA DEVICE/DRUG STATUS: C-JAWS staple: Not approved for this

indication.

doi: 10.1016/j.spinee.2010.07.346

P71. Changes in Coronal and Sagittal Plane Alignment after XLIF

Procedure in the Treatment of Degenerative Scoliosis

Leonardo Oliveira, BSc1, Luis Marchi, MSc2, Etevaldo Coutinho, MD2,

Luiz Pimenta, MD, PhD2; 1Universidade Federal de Sao Paulo, Sao Paulo,

Brazil; 2Instituto de Patologia da Coluna, Sao Paulo, Brazil

BACKGROUND CONTEXT: The traditional treatments to degenerative

scoliosis consist in open surgeries, with high incidence of morbidity. Here

we present a lateral retroperitoneal minimally invasive approach for the

treatment of adult scoliosis. Symptomatic adult scoliosis deformity

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

135SProceedings of the NASS 25th Annual Meeting / The Spine Journal 10 (2010) 1S–149S

presents as a difficult problem to solve. Traditional treatments include an-

terior and posterior open approaches.

PURPOSE: The purpose of this paper is to present a lateral retroperitoneal

minimally invasive approach (eXtreme Lateral Interbody Fusion - XLIF)

for the treatment of adult scoliosis requiring more than four levels of

arthrodesis without the morbidity of an open procedure.

STUDY DESIGN/SETTING: A prospective, non-randomized, single

center clinical trial.

PATIENT SAMPLE: 60 patients, mean age 66.95 (50–87 years), under-

went XLIF procedure to treat degenerative scoliosis.

OUTCOME MEASURES: Lateral, A-P, flexion-extension X-rays, neuro-

logical examination and clinical outcome assessments using Oswestry and

VAS scores were performed at the preoperative, 1, 6 week, 3, 6, 12, 24, 36,

48 and 60 months postoperative intervals.

METHODS: The extreme lateral approach was done through the retroper-

itoneal space and through psoas muscle avoiding vascular lesions. A partial

discectomy was done and the end-plate cleaned preserving ALL, keeping

the spine more stable than the traditional anterior surgery. The operated

levels ranged from four to seven levels, including T10-T11 to L4-L5

RESULTS: The procedures were performed without complication in an

average 121 minutes and with less than 50 cc blood loss. Ten patients

had four levels of fusion; two patients had five levels and two patients with

seven levels of arthrodesis. VAS pain scores improved from an average

8.33 at pre-op to 3.47 at 5 years, standard deviation 1.49 and 1.34 respec-

tively. Oswestry scores improved from an average 51.2 at pre-op to 29.52

at 5 years with standard deviation of 13.42 and 13.47 respectively. Coronal

and sagittal alignments improved from average Cobb angles of 16.4 de-

grees at pre-op and 7.5 degrees at 5 years, and average lordosis angles

of 17.1 degrees at pre-op to 34.2 degrees at 5 years.

CONCLUSIONS: Using the XLIF approach we were able to treat long

thoracolumbar deformities in a minimally invasive way targeting the pain im-

provement after surgery without the risks and morbidity associated with big

corrections. Our intent was pain improvement and stabilization. We found

reasonable coronal and sagittal correction in addition to successful clinical

improvements in pain and function in long thoracolumbar reconstructions.

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

any applicable devices or drugs.

doi: 10.1016/j.spinee.2010.07.347

P72. A Long-term Clinical Experience with Three Different Nucleus

Replacement Devices - Lessons Learned after 9-Years Follow-up

Leonardo Oliveira, BSc1, Luis Marchi, MSc2, Etevaldo Coutinho, MD2,

Luiz Pimenta, MD, PhD2; 1Universidade Federal de Sao Paulo, Sao Paulo,

Brazil; 2Instituto de Patologia da Coluna, Sao Paulo, Brazil

BACKGROUND CONTEXT: The nucleus replacement devices have

been developed for treating moderate forms of degenerative disc disease,

trying to fill the gap between discectomy and fusion. The surgical goals

are pain relief, maintenance of the disc height and flexibility at the index

and adjacent levels.

PURPOSE: The purpose of the present abstract is to show our experience

after 9 years using three different nucleus replacement prostheses.

STUDY DESIGN/SETTING: Prospective, non randomized, single center

clinical study.

PATIENT SAMPLE: 125 patients with moderate forms of degenerative

disc disease were enrolled in this study

OUTCOME MEASURES: Radiographic (AP, lateral and dynamic) and

clinical outcomes were collected preoperatively, 1 week and 1, 3, 6, 9,

and annually through 9 years postoperatively. The VAS and ODI question-

naires were used to assess pain and functional outcomes.

METHODS: 80 patients had PDN disc prosthesis, 26 patients with PNR

(Trans1) and 19 patients using theNUBAC (Pioneer) device. The surgical tech-

niques for each device were performed following the prosthesis indications.

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

RESULTS: After 9 years follow up, the global retrieval incidence was

48.8% (61/125). From these patients, 15 (57.7% of the specific device)

had PNR failures, 8 (42.1% of the specific device) experienced NUBAC

retrievals and 38 (47.5% of the specific device) had PDN flaws. The fail-

ures included significant loosening of the disc height at the operated level,

displacement, silicon inside de canal and migration. All patients underwent

fusion as a retrieval surgery

CONCLUSIONS: The retrieval rate in our series is very high. It shows

that the end-plate reaction in a long period of time happens, resulting in

important subsidence and mechanic back pain. The device expulsion

was another cause of pain and second surgery, as shown in the literature

FDA DEVICE/DRUG STATUS: TranS1 PNR, NUBAC: Investigational/

Not Approved; PDN: Approved for this indication.

doi: 10.1016/j.spinee.2010.07.348

P73. 2-Year Multicenter Follow-up in a Prospective Randomized

Clinical Trial: Comparison of a Cervical Artificial Disc to an ACDF

Treatment

Joseph Marzluff, MD1, Jeffrey McConnell, MD2, Christopher Tomaras,

MD3, Walter Peppelman, DO4, Ildemaro Volcan, MD5, Kelly Baker, PhD6;1Trident Regional Medical Center, North Charleston, SC, USA; 2Lehigh

Valley Hospital, Allentown, PA, USA; 3Peachtree Neurosurgery, Atlanta,

GA, USA; 4Spine Institute, Harrisburg, PA, USA; 5West Augusta Spine

Specialists, Augusta, GA, USA; 6Globus Medical, Inc., Audubon, PA, USA

BACKGROUND CONTEXT: Cervical arthroplasty may offer significant

benefits to patients such as alleviation of their pain and symptoms without

loss of motion at the involved vertebral segment and restoration of disc

height. Anterior cervical discectomy and fusion (ACDF) is the current

standard of care for the treatment of symptomatic cervical disc disease

(SCDD). Typically this treatment alleviates pain; however mobility and

normal physiological motion can be compromised.

PURPOSE: The design of this IDE study is to investigate the clinical re-

sults of traditional ACDF versus a cervical arthroplasty device.

STUDY DESIGN/SETTING: A prospective, randomized Investigational

Device Exemption (IDE) clinical trial of the SECURE�-C Cervical Artifi-

cial Disc (Globus Medical, Audubon, PA) is being conducted in the US.

The first five patients at all sites were treated with the artificial disc

(SEC) and all patients thereafter were randomized 1:1 to either control

ACDF or SEC. The ASSURE� Cervical Plate (Globus Medical, Audubon,

PA) and allograft spacer were used as the control ACDF treatment. Out-

comes from multiple centers (those that enrolled 10 patients or more)

are reported.

PATIENT SAMPLE: Patients presenting with single-level SCDD be-

tween C3 and C7 defined by neck and/or arm pain, HNP, radiculopathy

or myelopathy were enrolled. Patients were between 18 and 60 years

old, had to complete at least 6 weeks of conservative therapy, and have

a Neck Disability Index (NDI) of at least 30/100. Demographics were sim-

ilar for both treatment groups.

OUTCOME MEASURES: Evaluations are collected pre-operatively and

at 6 wk, 3 mo, 6 mo, 1 yr and 2 yr post-operatively. Outcome measure-

ments include NDI, Visual Analog Scale (VAS) neck and arm pain, patient

satisfaction and range of motion.

METHODS: Data from fourteen centers having received approval by their

Institutional Review Boards is presented. Of the 352 patients enrolled and

treated at these centers, 214 received SECURE�-C (70 of these were non-

randomized) and 138 received ACDF. Data are analyzed from 205 random-

ized patients (108 SEC and 97 ACDF) at 24 months postoperative.

RESULTS: Both SEC and ACDF cohorts demonstrated significant improve-

ment in NDI. Average NDI for SEC patients reduced from 52.0 613.8

pre-op to 12.3 618.2 at 24 months post-op as compared to 51.2 614.8

and 15.0 618.5, respectively, for ACDF. Eighty five percent of patients in

each group showed 25% or greater improvement in NDI at 24 months after

surgery. There were no significant differences in NDI outcomes between

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