Sacroiliac Joint Precision Treatment

A variety of radiofrequency procedures have been developed for the treatment of proven sacroiliac joint pain. The term "precision treatment" refers to treatment of a proven pain generator unlike treating "non-specific low back pain." In research either an intraarticular block or lateral branch blocks are performed for precision diagnosis, and two blocks are preferred to reduce the false positive rate. Lateral branch blocks do not necessarily block sensory information from the ventral surface of the joint. A 2015 systematic review by Simopopoulos et al of radiofrequency procedures found high heterogeneity, and a meta-analysis was not feasible. In general cooled radiofrequency is the only procedure with positive RCT evidence . The author is not aware of any Musculoskeletal Medicine specialists in New Zealand using cooled radiofrequency neurotomy for any use case. Traditional radiofrequency neurotomy for sacroiliac joint pain does not have good evidence. Repeated intraarticular prolotherapy injections is another treatment option with some evidence. 
==Intraarticular Injections==
There are two RCTs based on controlled blocks. An anteroposterior approach is faster and equal in efficacy to the traditional oblique approach.
 SIJ Intraarticular Injections RCTs
Study 	N 	Arms	Selection Criteria 	Results	Comments
Kim 2010 (RCT) 	50 	
# Fluoroscopic injections of 25% dextrose prolotherapy, up to 3 times, until >90% relief
#Fluoroscopic injections of 40mg triamcinolone, up to 3 times, until >90% relief	1 x positive intraarticular block (>50% pain relief)	✅Positive study
*Success defined as >50% relief
*2 weeks: 100% vs 100%
*6 months: 63.6% vs 27.2%
*15 months: 58.7% vs 10.2%
*Prolotherapy group needed more injections to reach initial 90% pain reduction (2.7 vs 1.5)	
*No placebo control
*Difference in number of injections, single block
Jee 2014 (RCT)Jee H, Lee JH, Park KD, Ahn J, Park Y. Ultrasound-guided versus fluoroscopy-guided sacroiliac joint intra-articular injections in the noninflammatory sacroiliac joint dysfunction: a prospective, randomized, single-blinded study. Arch Phys Med Rehabil. 2014;95(2):330-337. doi:10.1016/j.apmr.2013.09.021	120	
#Ultrasound guided with colour doppler (1 dominant colour to confirm IA) injection of lidocaine, omnipaque, plus 10mg dexamethasone. Accuracy assessed by fluoroscopy.
#Fluoroscopically guided injection of same	1 x positive intraarticular block (>80% pain relief) 	Focused more on accuracy of ultrasound rather than outcomes
Ultrasound group: 87% accuracy, Fluoroscopic group: 98.2% accuracy
No difference in pain scores and ODI at 2 and 12 weeks.	Looking at the utility of using ultrasound versus fluoroscopy
One retrospective case series investigated 150 patients with sacroiliac joint pain diagnosed clinically. All first had intraarticular bupivacaine and triamcinolone. 88 had at least 75% pain relief. Of those 88, 58 had a second injection of which 39 had further relief. Of those final 39 patients, 13 had at least 50% relief that lasted less than 6 weeks, and 26 (45%) had relief that lasted longer than 6 weeks (36.8 ± 9.9 weeks)Liliang PC, Lu K, Weng HC, Liang CL, Tsai YD, Chen HJ. The therapeutic efficacy of sacroiliac joint blocks with triamcinolone acetonide in the treatment of sacroiliac joint dysfunction without spondyloarthropathy. Spine (Phila Pa 1976). 2009 Apr 20;34(9):896-900. doi: 10.1097/BRS.0b013e31819e2c78. PMID: 19531998.
==Periarticular Injections==
No RCTs used controlled blocks for diagnosis. 2 x non-precision RCTs (Luukkainen et al 1999 and 2002) both positive results for steroid over saline.
==Radiofrequency Procedures==
===Sacroiliac Joint Innervation===
This topic is controversial. The literature is confusing because some studies have selected by positive lateral branch blocks, while others have selected by intraarticular blocks. Theoretically patients should be selected by lateral branch blocks.King and Bogduk. Chronic Low Back Pain In: Bonica's Management of Pain. 2018
*Ventral surface: Ventral root of L4/L5 – S2, or branches from sacral plexus
*Dorsal surface: Dorsal root of L4/L5, and S1-3 lateral branches.
*Ligaments: S1-3 lateral branches
Location is variable person to person, side to side, and level to level.
===Cooled Radiofrequency Neurotomy===
Cooled radiofrequency neurotomy techniques are the only intervention with positive RCT evidence.
 Cooled Radiofrequency Neurotomy
Study 	N 	Arms	Selection Criteria 	Results	Comments
Cohen et al 2008 (RCT) 	28 	
1. Cooled radiofrequency ablation of S1 to S3 lateral branches, and L5 dorsal ramus
2. Placebo RF	Single intraarticular block (>75% pain relief) 	✅Positive study
Success defined as pain <50%
*1 month: 79% vs 14%
*3 months: 64% vs 0%
*6 months: 47% vs not analysed	
*Local anaesthetic is considered an active control by some,
*Single block
Patel et al 2012 + 2015 (RCT)	120	
1. Cooled radiofrequency ablation of S1 to S3 lateral branches, and L5 dorsal ramus
2. Placebo RF	Two positive blocks lateral branches (>75% pain relief)	✅Positive study
Success defined as pain <50% plus improvement in another measure
*3 month: 47% vs 12%
*6 months: 38% vs not analysed
*9 months: 59%. vs NA
*12 months: 40% success vs NA	
*Local anaesthetic is considered an active control by some, unblinded at 3 months.
*How to explain wavy success curves
A retrospective trial by Cheng et al in 2013 compared cooled RF and traditional RF. Patients were selected based on >50% pain relief to two positive IA blocks. The two groups had equal outcomes. Success was defined as >50% pain relief. At 3 months: 50-60% both groups, 6 months: 40% both groups, 9 months: 30% both groups. There was bias potentially favouring CRF overall. The CRF group was younger, had more steroid (there was optional steroid given at the time to reduce neuritis), more lesions per level, and the patients had more previous spine surgery.
A meta-analysis was published in 2018 that included 7 studies, with 2 RCTs. Cooled RF had a mean 3.81 NRS reduction. Both RCTs were assessed as low risk of bias.
===Other Radiofrequency Techniques===
There is no positive RCT evidence for other techniques such as conventional, pulsed, strip, or bipolar radiofrequency neurotomy. Cohen in 2009 published a study which found that the only predictor of success was whether cooled RF was used. 
There is one negative RCT looking at the Simplicity III probe which allows a single point of entry to ablate the sacroiliac joint innervation in a strip lesion, plus a secondary entry point for the L5 dorsal root.
A non placebo controlled trial used heterogenous techniques (cooled, bipolar or simplicity III) and had negative results. This study, one part of a set of three RCTs on spinal RF treatments, has received a large amount of critisism.
===Surgery===
There are two positive non-placebo controlled RCTs evaluating minimally invasive sacroiliac joint fusion with the iFUSE implant system for confirmed sacroiliac joint pain based on a positive diagnostic block with greater than 50% pain relief. There were large improvements in pain and disability over the control group of conventional medical management. Polly et al allowed radiofrequency procedures, while Dengler et al didn't. These studies were industry funded, partially industry authored and had no sham group and so should be interpreted with caution.
The iFUSE system involves the fluoroscopic insertion of 2-4 triangular implants through the ilium across the sacroiliac joint into the centre of the sacrum lateral to the neural foramina. The implant is coated with a porous material allowing fixation of bone. The triangular shape allows immediate stabilisation and minimises micromotion and rotation of the joint.
==Quiz==
<quiz display=simple>
{With regards to sacroiliac joint innervation, which is true?
|type="()"}
- Innervation varies greatly between people, but each side of specific people is generally mirror imaged.
+ The dorsal surface can have a contribution from the L5 dorsal ramus
- The nerves run along the sacral bone very closely.
- The ventral surface of the joint is supplied by the S1-S3 lateral branches.
{MCQ: Which RF technique has the most evidence for reducing confirmed SIJ pain?
|type="()"}
- Conventional Radiofrequency
-Pulse Radiofrequency
-Strip Lesion Radiofrequency
+Cooled Radiofrequency
</quiz>
==Bottom Line==
*Intraarticular prolotherapy injections: 
*Intraarticular steroid injections: 
*Periarticular injections: 
*RF neurotomy: ~40% have >50% pain relief at 6 months, cooled and traditional may be equal.
*Minimally invasive fusion: 
==See Also==
*Lumbar Disc Precision Treatment
*Lumbar Facet Joint Precision Treatment
*Radiofrequency Neurotomy
*Chronic Low Back Pain
*Causes and Sources of Chronic Low Back Pain
==References==
Category:Partially complete articles
Category:Pelvis, Hip and Thigh Procedures
Category:Precision Techniques
Category:Sacroiliac Joint Procedures