Predictive Factors for LBP Interventional Treatment Outcomes

This will be an observational study with a 3-month follow-up. The course of clinical
treatment will be decided by a physician independent of the research. Besides filling out
questionnaires and standardized follow-up visits, all subjects will receive the same care
they would if they did not participate in the study. The study will be discussed with the
subjects and they will be enrolled in the study after it is determined that they meet
selection criteria and are scheduled for one of the above injections. They will then fill out
3 questionnaires (Oswestery disability index, Athens insomnia scale, QIDS SR-16. All
procedures will be performed with fluoroscopy. Following each procedure, the
procedure-related pain will be reported on a 0-10 scale (all patients will receive as much 1%
lidocaine local anesthetic as is necessary), including the reported pain to the standardized
skin wheal at the start of the procedure.

Patients will then receive standardized epidural steroid injections (transforaminal or
interlaminar), sacroiliac joint injections, or facet blocks and radiofrequency denervation if
they experience a positive block. Details about these procedures are available upon request.

No patients will be permitted additional interventions between the time of their procedure
and follow-up visits. Rescue medications will be in the form of either tramadol, NSAIDs or if
the patient is on opioids, a < 20% increase in dose. The first follow-up visit will be
scheduled 1 month from the start of treatment for ESI and SI joint patients, and 1 month
after RF denervation in positive diagnostic facet block responders. In those facet block
patients who obtain prolonged relief from the "diagnostic" medial branch block, follow-up
will be 1 month after the block (these patients may proceed to have denervation if their pain
recurs after 1 month but before their final 3-month follow-up, and their 3-month follow-up
will be 3 months after their medial branch block). A positive outcome will be defined as a
greater or equal to 2-point decrease in average LBP (or leg pain for those who underwent an
ESI) coupled with a positive satisfaction rating (> 3 on a 5-point scale). Subjects who
obtain a positive outcome at their initial 1-month follow-up visit will remain in the study
and return for the final 3-month follow-up visit. Those with a negative outcome will exit the
study "per protocol" to receive standard care, which may consist of other injections or
non-rescue medications such as antidepressants and anticonvulsants. Subjects who obtain a
positive outcome at 1-month but experience a recurrence before their 3-month follow-up visit
will also exit the study per protocol, with their final outcome measures recorded before they
receive standard care.

In those who receive ESI, a smaller parallel study will be done evaluating the association
between allergies and outcome. Allergies will be categorized as immunologically based or not.

Inclusion Criteria:

1. Age > 18 years;

2. Pain duration > 6 weeks;

3. Low back pain presumed to be secondary to herniated disc or spinal stenosis (e.g.
radiculopathy), facet joint pain or SI joint pain;

4. For ESI, patients must have leg pain >/= 4/10 or comparable or greater than back pain,
along with concordant MRI findings; for SI joint injections, patients must have
tenderness overlying the SI joint; for facet joint pain, they must have paraspinal
tenderness;

5. Patient agrees to have ESI, facet blocks or SI joint injection for diagnostic or
therapeutic purposes;

6. Average pain score >/= 4/10 over the past week

Exclusion Criteria:

1. Previous ESI, facet blocks or SI joint injection within the past 2 years;

2. Active inflammatory spondyloarthropathy (e.g. ankylosing spondylitis);

3. Previous surgery for ESI or facet block;

4. Untreated coagulopathy;

5. Allergy to contrast dye, bupivacaine or depomethylprednisolone;

6. Pregnancy;

7. Cannot read or understand English.