A Commentary on Appropriate Use Criteria for Sacroiliac Pain

Sacroiliac innervation

PURPOSE

To investigate the innervation pattern of the sacroiliac region, especially with regard to the sacroiliac joint (SIJ). Dorsal SIJ innervation was analyzed and described. Our main hypothesis was that nerves reach the SIJ dorsally, passing ligamental compartments, as this would explain dorsal SIJ pain.

METHODS

To examine sacroiliac innervation, we followed the nerves in over 50 specimens over several years. Plastinated slices were evaluated, nerves in the region were stained histologically, and the data were summarized as 3D models.

RESULTS

The Rami communicans and posterior branches of the spinal nerves and their branches that form a dorsal sacral plexus and communicating branches, together with corresponding vessels, were observed to form neurovascular bundles embedded by tiny fatty connectives in gaps and tunnels. Branches of L5-S1 pass the inner sacroiliac ligaments (the interosseous sacroiliac ligament and axial interosseous ligament). The outer sacroiliac ligaments (posterior sacroiliac ligaments, long posterior sacroiliac ligament, sacrotuberal ligament, thoracolumbar fascia) are passed by the S1-S4 branches. However, although the paths of these nerves are in the direction of the SIJ, they do not reach it. It is possible that impingement of the neurovascular bundles may result in pain. Moreover, the gaps and tunnels connect to the open dorsal SIJ.

CONCLUSION

Our findings suggest that Bogduk's term "sacroiliac pain" correlates to "sacroiliac innervation", which consists of "inner-" and "outer sacroiliac ligament innervation", and to ventral "SIJ pain". The watery gaps and tunnels observed could play a significant role in innervation and thus in the origins of SIJ pain.

LEVEL OF EVIDENCE

Individual cross-sectional studies with consistently applied reference standard and blinding.

Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group

BACKGROUND

The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial.

METHODS

In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement.

RESULTS

Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation.

CONCLUSIONS

Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group

BACKGROUND

The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial.

METHODS

In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement.

RESULTS

Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation.

CONCLUSIONS

Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Sacroiliac Joint Anatomy

The sacroiliac joint can be a source of low back pain. This review article summarizes current anatomic evidence of the innervation of the intraarticular and extraarticular parts of the sacroiliac joint relative to bony landmarks identifiable with fluoroscopy and ultrasound. This article aims to provide clinicians with an anatomic basis for clinical application to diagnostic blocks and radiofrequency ablation for sacroiliac pain to optimize clinical outcomes.

Consensus practice guidelines on interventions for lumbar facet joint pain from a multispecialty, international working group

BACKGROUND

The past two decades have witnessed a surge in the use of lumbar facet blocks and radiofrequency ablation (RFA) to treat low back pain (LBP), yet nearly all aspects of the procedures remain controversial.

METHODS

After approval by the Board of Directors of the American Society of Regional Anesthesia and Pain Medicine, letters were sent to a dozen pain societies, as well as representatives from the US Departments of Veterans Affairs and Defense. A steering committee was convened to select preliminary questions, which were revised by the full committee. Questions were assigned to 4-5 person modules, who worked with the Subcommittee Lead and Committee Chair on preliminary versions, which were sent to the full committee. We used a modified Delphi method, whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chair, who incorporated the comments and sent out revised versions until consensus was reached.

RESULTS

17 questions were selected for guideline development, with 100% consensus achieved by committee members on all topics. All societies except for one approved every recommendation, with one society dissenting on two questions (number of blocks and cut-off for a positive block before RFA), but approving the document. Specific questions that were addressed included the value of history and physical examination in selecting patients for blocks, the value of imaging in patient selection, whether conservative treatment should be used before injections, whether imaging is necessary for block performance, the diagnostic and prognostic value of medial branch blocks (MBB) and intra-articular (IA) injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for a prognostic block, how many blocks should be performed before RFA, how electrodes should be oriented, the evidence for larger lesions, whether stimulation should be used before RFA, ways to mitigate complications, if different standards should be applied to clinical practice and clinical trials and the evidence for repeating RFA (see table 12 for summary).

CONCLUSIONS

Lumbar medial branch RFA may provide benefit to well-selected individuals, with MBB being more predictive than IA injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of more false-negatives. Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Successful Thermal Neurotomy of the Painful Sacroiliac Ligament/Joint Complex—A Comparison of Two Techniques

Background

There are many physical, pharmacological, and interventional therapies aimed at alleviating sacroiliac ligament/joint complex pain, including thermal neurotomy. Sacroiliac joint (SIJ) innervation, as opposed to posterior sacroiliac ligament complex innervation, remains uncertain; thus lateral branch thermal neurotomy to alleviate sacroiliac joint pain remains controversial.

Objective

This study aimed to compare the success rates of two lateral branch neurotomy techniques, large continuous-lesion multi-electrode radiofrequency neurotomy (RFN; Simplicity, Neurotherm Inc.) and small-lesion monopolar periforaminal, to relieve pain from sacroiliac joints, as well as whether these would alter physical and psychological health.

Design

Retrospective clinical audit of prospectively gathered consecutive data.

Setting

A private community-based multidisciplinary pain clinic.

Subjects

Referred from primary care environments.

Methods

Of 96 consecutive thermal neurotomies with baseline data completed, follow-up data were found in 73 patients during the period 2011–2017. After diagnosis by dual-positive fluoroscopic intra-articular injections, 41 patients underwent 47 monopolar periforaminal neurotomies, and 32 underwent 49 large continuous-lesion multi-electrode RFNs, with >12-month follow-up. The primary outcome was 50–100% relief of pain for more than six months. Results are presented as success rates. Secondary outcomes were Functional Rating Index Depression Anxiety and Stress Scale and Patient Specific Functional Scale.

Results

Follow-up data were available for 80 (83%) of the 96 procedures. Success occurred in 69% of all procedures (39% complete >75% relief and 30% good 50–75% relief). Success was 57% with worst-case analysis. Success rates were 71% in the large continuous-lesion multi-electrode RFN group and 65% in the periforaminal group, with overlapping confidence intervals. Significant improvements also occurred in the secondary measures.

Conclusions

Thermal neurotomy demonstrated a 69% success rate in reduction of sacroiliac ligament/joint complex pain for more than six months equally by large continuous-lesion multi-electrode RFN and periforaminal monopolar techniques, with attendant improvement in physical and psychological function.