METHODS: Clinical data was recorded for each patient pre-operatively and

at their final clinic visit. Possible independent predictors of work status were:

pre-operative use of opioids, location of pain, post-operative use of opioids,

and the severity of pain pre-operatively measured on the visual analog scale.

RESULTS: Patients were followed post surgery for 24614 months (range

of 9 to 57 months). The age range of this patient population was 22 to 72

(mean 47611); and consisted of 36 (54.5%) women and 30 (45.5%) men.

Twenty-nine (43.9%) of the patients were on an opioid before surgery (11

(50.0%) WC; 18 (40.9%) CG; p50.483). Thirteen (19.7%) patients pre-

sented with low back pain only, 47 (71.2%) had low back pain and radicul-

opathy, and 6 (9.1%) had radiculopathy alone. Pain location did not differ

statistically between WC and CG, p50.976. Sixteen (72.7%) of WC pa-

tients had low back pain and radiculopathy compared to 31 (70.5%) of

CG patients. Two (9.1%) WC patients had radiculopathy alone compared

to 4 (9.1%) CG patients. Seventeen (25.8%) patients were still on an opioid

at follow-up (9 (40.9%) WC and 8 (18.2%) CG, p50.047). Patient’s per-

ception of pain between the two groups did not differ statistically. WC pa-

tients ranked their pain preoperatively on the VAS scale an average of

6.662.1 and the CG patients ranked their preoperative pain an average

of 6.662.3, p50.938. Eleven (50.0%) of WC patients had returned to work

without limitations at the time of follow-up compared to 39 (88.6%) of the

CG, p50.001. Logistic Regression analysis identified worker’s compensa-

tion and the use of opioids at follow-up as the strongest independent pre-

dictors of poor work status at follow-up.

CONCLUSIONS: The CG patients were about half as likely to take opi-

oids after surgery than the WC patients and about twice as likely to return

to work without restrictions.

FDA DEVICE/DRUG STATUS: rhBMP-2: Not approved for this

indication.

doi: 10.1016/j.spinee.2009.08.302

P45. ACDF with Peek Interbody Cages and rhBMP-2: A Single

Surgeons Experience

Jessica Clarke, BSC, Gregory Bailey, DO, Joel Torretti, MD; University

Orthopedics Spine Center, State College, PA, USA

BACKGROUND CONTEXT: There has been a mixed body of literature

regarding the safety and efficacy of rhBMP-2 (Infuse) use in the cervical

spine. There have been a number of published series demonstrating a com-

plication rate consistent with historical rates without rhBMP-2, yet other

case reports have identified postoperative swelling requiring reintubation

and reoperation raised concerns about the safety of the product. These con-

cerns prompted this review of a single surgeon’s experience with 45 cases

performed prior to the FDA issued warning.

PURPOSE: The purpose was to evaluate complication rate including: dys-

phagia, readmission, and reoperation in 45 patients. A secondary purpose

was to evaluate fusion rate in the same patient population.

STUDY DESIGN/SETTING: This is a retrospective case series with

a single surgeon at a single institution.

PATIENT SAMPLE: A consecutive series of patients in a single practice

treated for radiculopathy, myelopathy, and myeloradiculopathy prior to the

FDA issued warning. All patients underwent a one to three level ACDF

with a PEEK spacer and Infuse rhBMP-2 and anterior instrumentation.

Follow-up ranged from 6 to 38 months with a mean follow-up of 13.5

months. 13 three level (29%), 16 two level (36%) and 16 single level fu-

sions (36%) were performed. 20/45 (44%) were female and 20/45 (56%)

were male patients. 12/45 (27%) of patients were smokers.

OUTCOME MEASURES: Odoms criteria and radiographic fusion rate.

METHODS: Data obtained in 45 cases were retrospectively evaluated. Pa-

tients records were scored using Odoms criteria for clinical outcome as-

sessment and complication rates by an independent reviewer. Plain

radiographs were reviewed by a second independent reviewer (practicing

spine surgeon) to determine fusion rate.

RESULTS: There was a 100% fusion rate by the one year visit. Mild-mod-

erate dysphagia was reported in 14/45 (31%) of patients at 6 weeks, 1/45 (2%)

of patients at 6 months and 1/45(2%) at one year. A single patient who had

undergone a three level ACDF was readmitted to the hospital and underwent

reoperation for evacuation of a hematoma post-op day four (2%) without any

airway compromise. Clinical outcomes as assessed by Odom’s criteria were:

good/excellent in 100% of patients by the one year follow-up visit.

CONCLUSIONS: The use of rhBMP-2 in a PEEK cage in single and mul-

tilevel ACDF leads to a consistent fusion rate and successful clinical out-

ocme in the majority of patients. The safety of rhBMP-2 in the cervical

spine in this single surgeon case series is consistent with historical rates

of dysphagia and reoperation previously reported.

FDA DEVICE/DRUG STATUS: INFUSE rhBMP-2: Not approved for

this indication; PEEK Interbody Spacer: Investigational/Not approved.

doi: 10.1016/j.spinee.2009.08.303

P46. Morphometric Analysis of the Ventral Nerve Roots and

Retroperitoneal Vessels with Respect to the Minimally Invasive

Lateral Approach in Normal and Deformed Spines

Gilad J. Regev, MD, Lina Chen, MD, Mallika Dhawan, BS, Yu-Po Lee, MD,

Steven R. Garfin, MD, Choll W. Kim, MD, PhD; University of California,

San Diego, San Diego, CA, USA

BACKGROUND CONTEXT: The lateral approach to the lumbar spine is

a relatively new method for performing interbody fusions. In contrast to

the standard open anterior approach with direct vision of the operative

field, the lateral approach uses expandable retractors that are positioned

under fluoroscopic guidance. Risks of this technique include injury to

the exiting nerve root and retroperitoneal vessels.

PURPOSE: To identify the anatomic position of the ventral root and the

retroperitoneal vessels in relation to the vertebral body in normally aligned

and deformed spines.

STUDY DESIGN/SETTING: A morphometric analysis, using MRI stud-

ies of the lumbar spine.

PATIENT SAMPLE: One hundred lumbar spine MRI studies

OUTCOME MEASURES: N/A

Figure.

METHODS: One hundred lumbar spine MRI studies were reviewed from

patients that treated for various spinal pathologies. The measured interverte-

bral segments were divided into 3 groups: Group 1 (n5247) normally aligned

vertebrae and disc spaces, Group 2 (n519) degenerative spondylolisthetic

segments, Group 3 (n519) segments from the apex of degenerative lumbar

138S Proceedings of the NASS 24th Annual Meeting / The Spine Journal 9 (2009) 1S-205S