EBM of Intradiscal Electrothermal Therapies

EBM of Intradiscal EBM of Intradiscal Electrothermal TherapiesElectrothermal Therapies

Ray M. Baker Ray M. Baker Clinical Professor of Anesthesiology Clinical Professor of Anesthesiology

University of WashingtonUniversity of WashingtonNASS, Spring Break 2006, Back to The NASS, Spring Break 2006, Back to The

EvidenceEvidence

Reporter: Yuan-Chun Huang

EBM HierarchyEBM Hierarchy

Synthesis (e.g. Cochrane) Synthesis (e.g. Cochrane)

Studies Studies

RCT > Case control > Case Series > RCT > Case control > Case Series >

Retrospective > Case reports Retrospective > Case reports

Levels of Evidence: Cochrane Levels of Evidence: Cochrane

. Level A: strong research-based evidence provided by . Level A: strong research-based evidence provided by generally consistent findings in generally consistent findings in multiple high-quality multiple high-quality RCTs; RCTs; . Level B: moderate research-based evidence provided . Level B: moderate research-based evidence provided by generally consistent findings in by generally consistent findings in one high-quality RCTone high-quality RCT plus one or more low-quality RCTsplus one or more low-quality RCTs, or generally , or generally consistent findings in multiple low-quality RCTs; consistent findings in multiple low-quality RCTs; . Level C: limited or conflicting research-based evidence . Level C: limited or conflicting research-based evidence provided by provided by one RCT (either high or low qualityone RCT (either high or low quality) or ) or inconsistent findingsinconsistent findings in multiple RCTs; in multiple RCTs; . Level D: no research-based evidence i.e., no RCTs. . Level D: no research-based evidence i.e., no RCTs.

IDETIDET

IDET: RationaleIDET: Rationale

Proposed mechanism of action: Proposed mechanism of action:

Stiffening and strengthening of the Stiffening and strengthening of the collagen? collagen?

Deactivation of inflammatory enzymes / Deactivation of inflammatory enzymes / chemicals? chemicals?

coagulation of posterior annular coagulation of posterior annular nociceptive pain fibers? nociceptive pain fibers?

IDET EvidenceIDET Evidence

Synthesis – 1 Chou AJPMR 2005Synthesis – 1 Chou AJPMR 2005( Chou LH, Lew HL, Coelho PC, Slipman CW: Intradiscal electrothermal ( Chou LH, Lew HL, Coelho PC, Slipman CW: Intradiscal electrothermal

annuloplasty. Am J Phys Med Rehabil 2005;84:538-549. )annuloplasty. Am J Phys Med Rehabil 2005;84:538-549. )

Studies Studies

# RCTs – 2 (Pauza and Freeman) # RCTs – 2 (Pauza and Freeman)

# Several prospective case control studies # Several prospective case control studies and cohort control studies. and cohort control studies.

# Several prospective observational, # Several prospective observational, retrospective studies, and case series.retrospective studies, and case series.

Pauza, TSJ 2004Pauza, TSJ 2004

Pauza, Howell, Dreyfuss et al.Pauza, Howell, Dreyfuss et al.

A randomized placebo-controlled Trial of A randomized placebo-controlled Trial of IDET for the treatment of discogenic LBP.IDET for the treatment of discogenic LBP. The Spine J 2004; Volume 4: Issue 1, 27-35.The Spine J 2004; Volume 4: Issue 1, 27-35.

Pauza, TSJ 2004 Pauza, TSJ 2004

4,523 patients inquired about the study; after 4,523 patients inquired about the study; after phone interview 1,360 underwent an interview phone interview 1,360 underwent an interview and physical examination and physical examination

260 met initial criteria and underwent 260 met initial criteria and underwent discography discography

64 patients eligible after discography. 64 patients eligible after discography.

37 randomized to IDET. 37 randomized to IDET. 27 randomized to sham. 27 randomized to sham.


Patient selection criteria: Patient selection criteria:

Discogenic LBP > 6 months in duration. Discogenic LBP > 6 months in duration. LBP > leg pain. LBP > leg pain. Less than 20% disc height narrowing on Less than 20% disc height narrowing on lateral plain film radiographs. lateral plain film radiographs. Beck depression scale score less than 20. Beck depression scale score less than 20. No co-morbid conditions. No co-morbid conditions.

Pauza, TSJ 2004 Pauza, TSJ 2004

.Exclusion Criteria .Exclusion Criteria

#.Previous lumbar #.Previous lumbar spine surgery spine surgery

#.Abnormal #.Abnormal neurological exam neurological exam

#.Radicular pain #.Radicular pain #.Chronic medical #.Chronic medical

conditions conditions

#.Central or foraminal #.Central or foraminal stenosis stenosis #.Intervertebral disc #.Intervertebral disc herniations > 4 mm. herniations > 4 mm. #.Cervical or thoracic #.Cervical or thoracic pain > than 2/10. pain > than 2/10. #.Gait altering LE #.Gait altering LE conditions conditions


IDET. IDET.

# Catheter passed circumferentially to # Catheter passed circumferentially to completely cover the posterior anulus completely cover the posterior anulus (bilateral passes if needed) (bilateral passes if needed)

# Catheter heated to final temperature of 90° # Catheter heated to final temperature of 90° C via the standard 16.5 minute protocol C via the standard 16.5 minute protocol


Sham. Sham.

# Introducer passed to postero-lateral # Introducer passed to postero-lateral aspect of disc, but disc never entered aspect of disc, but disc never entered

# 16.5 mins passed, sounds/images of IDET # 16.5 mins passed, sounds/images of IDET

# Sedation (versed) used as in IDET group # Sedation (versed) used as in IDET group


Blinding process was maintained-Blinding process was maintained-approximately 75% in both groups approximately 75% in both groups believed they had the real treatment believed they had the real treatment

8 patients (12.5%) excluded. (including: 8 patients (12.5%) excluded. (including: unacceptable catheter placement, died, unacceptable catheter placement, died, concurrent illness, non-compliant with concurrent illness, non-compliant with follow up, drug abuse)follow up, drug abuse)


SF 36: SF 36: (The Medical Outcome Study 36-item short-form health (The Medical Outcome Study 36-item short-form health survey )survey )

no statistically significant difference. no statistically significant difference.

Oswestry disability scale: IDET > placebo Oswestry disability scale: IDET > placebo (p=0.038) (p=0.038)

VAS Mean ↓ 2.4 IDET vs. 1.2 Sham VAS Mean ↓ 2.4 IDET vs. 1.2 Sham

50% of patients unchanged. 50% of patients unchanged.




IDET is not a placebo treatment .IDET is not a placebo treatment .

However, after a very rigorous screening However, after a very rigorous screening process IDET substantially reduces pain in process IDET substantially reduces pain in only 1 of 5 only 1 of 5

Freeman, Spine 2005Freeman, Spine 2005

Freeman BJ, Fraser RD, Cain CM, Hall DJ, Chapple DC.Freeman BJ, Fraser RD, Cain CM, Hall DJ, Chapple DC.

A Randomized, Double-Blind, Controlled A Randomized, Double-Blind, Controlled Trial Intradiscal Electrothermal Therapy Trial Intradiscal Electrothermal Therapy Versus Placebo for the Treatment of Versus Placebo for the Treatment of Chronic Discogenic Low Back Pain.Chronic Discogenic Low Back Pain.

Spine 2005; Volume 30( Number 21): pp 2369 -2377. Spine 2005; Volume 30( Number 21): pp 2369 -2377.



Inclusion Criteria: Inclusion Criteria: # LBP > LE pain # LBP > LE pain # Disc Height > 50% # Disc Height > 50% # 1 or 2 level disc degeneration # 1 or 2 level disc degeneration # Discography (+) with normal control # Discography (+) with normal control # No prior surgery # No prior surgery # Sitting Tolerance > Standing tolerance # Sitting Tolerance > Standing tolerance # Normal neurologic exam # Normal neurologic exam




No statistically significant difference in any No statistically significant difference in any of the outcome measurements. of the outcome measurements.

Even looking at subsets, did not result in Even looking at subsets, did not result in any subset reaching a p value close to any subset reaching a p value close to 0.05. 0.05.

Zero placebo Zero placebo

Levels of Evidence: IDETLevels of Evidence: IDET

EquivocalEquivocal . .

Level CLevel C: limited or conflicting research-: limited or conflicting research-based evidence provided by one RCT based evidence provided by one RCT (either high or low quality) or inconsistent (either high or low quality) or inconsistent findings in multiple RCTs; findings in multiple RCTs;

Pauza et al may well have shown Pauza et al may well have shown statistical significance between their two statistical significance between their two groups, but Freeman et al would argue groups, but Freeman et al would argue that this does not necessarily equate to that this does not necessarily equate to clinical significance. clinical significance.

One thing is clear from the literature: that One thing is clear from the literature: that highly selected groups of patients are highly selected groups of patients are required to show only marginal benefit required to show only marginal benefit from the procedure and that IDET is not from the procedure and that IDET is not beneficial for the vast majority of patients beneficial for the vast majority of patients with CDLBP. with CDLBP.

Thanks for attention!Thanks for attention!

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EBM of Intradiscal Electrothermal Therapies