Chris:
LSU's library doesn't subscribe to that journal, so my comments are based only on the abstract of Dr. Murakami's study.
No one provocative test provides more than 64% sensitivity for SIJ pain (
Diagnosis of sacroiliac joint pain: validity of individual provocation tests and composites of tests, Man Ther. 2005 Aug;10(3):207-18.) Selection criteria is also the primary flaw in another study Dr. Kishner may be referencing from last year:
Sources of sacroiliac region pain: insights gained from a study comparing standard intra-articular injection with a technique combining intra- and peri-articular injection.
Borowsky CD,
Fagen G.
Arch Phys Med Rehabil. 2008 Nov;89(11):2048-56
OBJECTIVES: To present evidence supporting the existence of extra-articular sources for sacroiliac region pain and to present evidence that intra-articular anesthetic blockade may underestimate the true prevalence of sacroiliac region pain. DESIGN: Retrospective review of 2 large case series comparing patient responses to intra-articular injection versus combined intra-articular and peri-articular injection of anesthetic and corticosteroid. SETTING: Private practice chronic pain clinic set in a hospital outpatient clinic. PARTICIPANTS: Patients (N=120) sequentially enrolled from practice billing records. Inclusion criteria included pain in the low back below L4 and in the buttock, thigh, groin, or lower leg. If disk herniation, lumbar stenosis, or facet syndrome was previously treated with appropriately chosen injections, response to treatment had to be negative. Patients failed to respond to treatment with physical therapy. Exclusion criteria included records with an incomplete database, patients increasing pain medication use greater than 15% for pain not related to the sacroiliac region, severe psychiatric illness, and nonspecific anesthetic blockade. One hundred sixty-seven records were reviewed to obtain the 120 study subjects. INTERVENTIONS: Intra-articular injection was done according to the standard technique described by Fortin. Peri-articular injection was done by a slight modification of the procedure described by Yin. MAIN OUTCOME MEASURES: Percentage change in visual analog scale (VAS) pain scores at 3 weeks and 3 months postinjection; patients' self reported activities of daily living (ADLs) improvement at 3 weeks and 3 months postinjection; and percentage change in VAS pain score within 1 hour of injection. RESULTS: For intra-articular injection alone, the rate of positive response at 3 months was 12.50% versus 31.25% for the combined injection (P=.025). Positive response was defined as greater than 50% drop in VAS pain score or patients describing ADLs as "greatly improved." Anesthetic response rates were higher in the combined injection group (62.5% vs 42.5%; P=.037). CONCLUSIONS: Significant extra-articular sources of sacroiliac region pain exist. Intra-articular diagnostic blocks underestimate the prevalence of sacroiliac region pain.
The Japanese study you cite claims effectiveness in ALL patients who received peri-articular injections. The
Archives study reports 31.25% positive response for combination intra and extra-articular injections. The inadequate physical exam ("After a pain provocation test") sensitivity leads me to believe there is no way every patient included in the Japanese study had primary SIJ pain. The
Archives study inclusion criteria (pain in the low back below L4 and buttock, thigh, calf, or groin pain) was equally suspect, because facetogenic pain was never ruled out. Their results are much more reasonable in light of that selection criteria failing, and the 100% success of the Japanese study is quite simply unbelievable.
The
Archives study addressed both the posterior interosseous ligament and S1-3 lateral branches. Given the variability of the location of the lateral branches, as well as the 10-20% likelihood of vascular uptake of your therapeutic solution, injecting those structures without the benefit of fluorscopic guidance seems futile.
Lastly, when studies report long-term relief from an injection of materials into unconstrained spaces (e.g. MBBs), I personally am forced to question their construct validity. From my perspective, I remain baffled how we can ascribe therapeutic benefit at three months to local anesthetic and steroid that likely floated off no more than a few minutes to hours after they were injected.
Actually, watching the expertise of someone like him or our other pain doc is kind of intimidating. I can't imagine how anyone could be as skilled as that without fellowship training. But I know a lot of people go out and practice without fellowships.
