Efficacy and Cost: Benefit Ratio of 0, 1, and 2 Medial Branch Blocks for Lumbar Facet Joint Radiofrequency Denervation

This study has been completed.
Sponsor:
Information provided by:
Johns Hopkins University
ClinicalTrials.gov Identifier:
NCT00484159
First received: June 6, 2007
Last updated: July 25, 2011
Last verified: January 2009
  Purpose

Lumbar zygapophysial (facet) joint pain is a common cause of low back pain. Radiofrequency (RF) denervation is an effective and low risk treatment of chronic low back pain of suspected facet joint etiology. Blocks of the medial branches innervating the joints are commonly used to localize the pain and make the diagnosis of facet joint pain.

There is currently no standard number of diagnostic blocks: zero, one, and two blocks have all been utilized. Considering the high false positive and false negative rates of these blocks, the cost: benefit ratio has been questioned. No study to date has examined the practice of diagnostic medial branch blocks before RF denervation.

The purpose of this study is to determine the optimal number of blocks before radiofrequency denervation. Three groups of patients will be studied. In group I, patients will undergo RF denervation based on history and physical exam alone. In group II, patients will undergo RF denervation based on a positive response to a single diagnostic block with local anesthetic. In group III, patients will undergo RF treatment only after a positive screening block and a positive confirmatory block.


Condition Intervention
Low Back Pain
Procedure: Radiofrequency denervation of medial branches
Drug: 0.5% bupivacaine
Drug: 2% lidocaine
Procedure: Radiofrequency denervation

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Prospective Randomized Study Comparing 0, 1, and 2 Diagnostic Lumbar Medial Branch (Facet Joint) Blocks Before Radiofrequency Denervation in Patients With Chronic Low Back Pain: A Cost: Benefit Analysis.

Resource links provided by NLM:


Further study details as provided by Johns Hopkins University:

Primary Outcome Measures:
  • Cost Per Successful Procedure [ Time Frame: 3-months ] [ Designated as safety issue: No ]
    Total cost per effective treatment at 3-months. Successful procedure defined as greater or equal to 50% pain relief and satisfaction lasting at least 3 months.


Secondary Outcome Measures:
  • Successful Treatment [ Time Frame: 3-months postprocedure ] [ Designated as safety issue: No ]
    Greater or equal to 50% pain relief plus procedural satisfaction lasting at least 3 months. What is being measured is the number of participants with a positive outcome.


Enrollment: 151
Study Start Date: February 2007
Study Completion Date: January 2009
Primary Completion Date: January 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
Radiofrequency lumbar facet joint denervation only if positive response to 2 diagnostic facet blocks.
Procedure: Radiofrequency denervation of medial branches
Radiofrequency of medial branches that innervate the lumbar facet joints
Drug: 0.5% bupivacaine
Diagnostic medial branch block with 0.5% bupivacaine. Blocking the nerves that innervate the facet joints with a long-acting local anesthetic.
Drug: 2% lidocaine
Diagnostic medial branch block with 2% lidocaine. Blocking the nerves that innervate the facet joints with a short-acting local anesthetic.
Procedure: Radiofrequency denervation
Radiofrequency lumbar facet denervation only if positive response to 2 diagnostic blocks.
Experimental: 2
Radiofrequency lumbar facet joint denervation if positive response to single facet joint block.
Procedure: Radiofrequency denervation of medial branches
Radiofrequency of medial branches that innervate the lumbar facet joints
Drug: 0.5% bupivacaine
Diagnostic medial branch block with 0.5% bupivacaine. Blocking the nerves that innervate the facet joints with a long-acting local anesthetic.
Procedure: Radiofrequency denervation
Lumbar facet radiofrequency denervation if positive response to a single diagnostic facet block
Experimental: 3
Radiofrequency lumbar facet denervation without a diagnostic facet block.
Procedure: Radiofrequency denervation of medial branches
Radiofrequency of medial branches that innervate the lumbar facet joints
Procedure: Radiofrequency denervation
Radiofrequency lumbar facet denervation without a diagnostic block
Procedure: Radiofrequency denervation
Radiofrequency lumbar facet denervation without a diagnostic facet block.

Detailed Description:

Lumbar zygapophysial (facet) joints are recognized as one of the most common causes of chronic low back pain with an estimated prevalence among patients with LBP ranging from 15% to 40%. Radiofrequency (RF) denervation of facet joints has been utilized as an effective treatment of chronic pain attributed to these joints. Blocks of the medial branches innervating the joints are commonly used to localize the pain and make a diagnosis of lumbar zygapophysial (l-z) joint pain. However, considering the high false-positive rates of these blocks (25-40%), the false-negative rates (8-10%), and the number of blocks necessary to make the diagnosis before treatment, the cost-effectiveness of performing these blocks and the benefit of exposing these patients to additional risks is under question. The risks of RF denervation are so low (equivalent to performing the diagnostic block), some have questioned whether or not any diagnostic facet blocks should be performed before RF lesioning.

The purpose of the study is to determine the optimal number of diagnostic blocks that should be performed before radiofrequency denervation in patients with chronic lower back pain with suspected facet joint etiology.

In this prospective randomized study, we will recruit 150 patients with suspected chronic (l-z) joint pain without neurological symptoms to undergo one of three treatment modalities. In group I, 50 patients will undergo RF denervation based on history and physical exam alone (what we advocate in a recent review article). In group II, 50 patients will receive a single diagnostic block with 0.5% bupivacaine. Those that obtain greater than 50% pain reduction will undergo RF denervation. In group III, 50 patients will receive a block with either 2% lidocaine or 0.5% bupivacaine. Those patients that obtain greater than 50% pain relief with the first block receive a second block with the other local anesthetic. Patients that obtain greater than 50% pain relief with the second block then undergo RF. Patients in any group that obtain less than 50% pain relief with any block exit the study.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Axial low back pain unresponsive to conservative treatment measures such as physical therapy, manual therapy and pharmacotherapy
  • Duration of pain greater than 6 months

Exclusion Criteria:

  • Age younger than 18 years
  • Objective evidence (MRI or physical exam findings) of lumbosacral radiculopathy
  • Prior radiofrequency treatment
  • Significant spinal stenosis or spondylolisthesis
  • Previous back surgery
  • Uncorrected coagulopathy
  • Unstable medical or psychiatric condition
  • Pregnancy
  • Allergies to local anesthetic
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00484159

Locations
United States, District of Columbia
Walter Reed Army Medical Center
Washington, D.C., District of Columbia, United States, 20307
United States, Maryland
Johns Hopkins Hospital
Baltimore, Maryland, United States, 21287
Sponsors and Collaborators
Johns Hopkins University
Investigators
Principal Investigator: Steven P Cohen, MD Johns Hopkins School of Medicine, Walter Reed Army Medical Center
  More Information

No publications provided

Responsible Party: Office of Research Administration, Amanda Gibson
ClinicalTrials.gov Identifier: NCT00484159     History of Changes
Other Study ID Numbers: NA_00007158
Study First Received: June 6, 2007
Results First Received: June 22, 2011
Last Updated: July 25, 2011
Health Authority: United States: Institutional Review Board

Keywords provided by Johns Hopkins University:
Low back pain of suspected lumbar zygapophysial etiology

Additional relevant MeSH terms:
Back Pain
Low Back Pain
Pain
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms
Bupivacaine
Lidocaine
Anesthetics, Local
Anesthetics
Central Nervous System Depressants
Physiological Effects of Drugs
Pharmacologic Actions
Sensory System Agents
Peripheral Nervous System Agents
Central Nervous System Agents
Therapeutic Uses
Anti-Arrhythmia Agents
Cardiovascular Agents
Voltage-Gated Sodium Channel Blockers
Sodium Channel Blockers
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action

ClinicalTrials.gov processed this record on September 18, 2014