Study Of Disc Anaesthesia For The Preoperative Diagnosis Of Chronic Lower Back Pain

Inclusion Criteria:

- Age > 21.

- Chronic axial low back pain without radicular pain for > six months, not responding to
at least three months of non-surgical management under the direction of a physician.

- One or two discs at L5/S1, L4/L5 or L3/L4 with abnormal findings by MRI, including any
of the following: loss of disc hydration, loss of disc height, high intensity zone
(HIZ), Modic changes at adjacent vertebral endplates, or herniation without nerve root
compression.

- Subject states that he/she is willing to undergo lumbar spinal fusion, disc
replacement, or other definitive treatment if eventual diagnosis supports such
treatment.

- Physician believes that discography is clinically indicated for the purpose of
surgical decision-making for the subject.

- Pre-treatment low back pain by numerical rating scale (NRS) score > 4 (measured as
average in last 24 hours on a 0-10 scale).

- Pre-treatment Oswestry Disability Index (ODI) > 40 (0 - 100 scale).

- Subject states availability for all study visits.

- Subject is able to understand the risks and benefits of participating in the study and
provides written informed consent.

Exclusion Criteria:

- Known osteoporosis or osteopenia, metabolic bone disorder, or history of chronic
steroid use (the equivalent of 7.5 milligrams of daily prednisone use for > 6 months).

- Suspected painful disc degeneration (based on clinical examination and MRI findings)
outside of L5/S1, L4/L5 or L3/L4 levels.

- MRI shows disc abnormalities (listed in Inclusion Criteria #3) at all 3 lower lumbar
discs (L3/L4, L4/L5 and L5/S1).

- Abnormal neurologic exam attributable to lumbar disc disease, herniation, or lumbar
stenosis.

- Back, buttock or pelvic pain suspected to be due to spinal stenosis, spinal fractures,
infection, cancer, facet arthropathy or other hip or pelvis pathology.

- Schmorl's node or endplate disruption evident on MRI at L5/S1, L4/L5, or L3/L4.

- Medical history, physical examination or radiographic evidence (e.g., disc height too
narrow) to suggest that either PD or F.A.D. may not be technically feasible.

- Any previous lumbar spine fusion or disc replacement.

- More than grade 1 spondylolisthesis as assessed by x-ray or MRI.

- Significant clinical comorbidity that may potentially interfere with data collection
or follow-up (e.g., dementia, severe comorbid illness).

- History of major depression, psychosis or somatization disorder, or panic disorder.

- Allergy to any materials used in PD or F.A.D. devices, contrast, lidocaine, or
bupivacaine.

- Any evidence of disc or systemic infection.

- Pregnant or child-bearing potential and not currently on adequate birth control
method.