Pain, ChronicOMEGANCT05961800
Offset Mechanisms in Evaluation of Lumbar Medial Branch Blocks
A study testing Cutaneous Probe, Quantitative Sensory Testing and Computer Tasks in people with Pain, Chronic and Facet Joint Pain, run by University of Pittsburgh at 1 site in United States.
Trial summary
This study examines the relationship between central nervous system (CNS) mechanisms of pain inhibition and the pain relief that occurs following a lumbar medial branch block (MBB). Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Pain, Chronic, Facet Joint Pain, Pain, Procedural
- What is being tested?
- Cutaneous Probe, Quantitative Sensory Testing and Computer Tasks
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 40 participants
- Where
- 1 siteUnited States
- Study dates
- 5 Jul 2023to Jun 2028
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Scheduled for lumbar MBB in UPMC Pain Management clinics
- Age > 18 years old
- Predominantly axial chronic low back pain at least 3 months on a daily basis
- Must meet the minimum criteria for cognitive function using the PROMIS 2-item cognitive screener (>3)
- Low back pain intensity of > 3/10
- Willing and able to receive study-related phone calls
Who cannot join
- History of spine surgery at the level of the lumbar MBB
- Active worker's compensation or litigation claims
- New pain and/or psychiatric treatments within 2 weeks of enrollment
- Not fluent in English and/or not able to complete the questionnaires
- Any clinically unstable systemic illness that is judged to interfere with the study
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
UPMC St. Margaret
Pittsburgh, Pennsylvania, 15215
Maya L Maurer, BS, 412-665-8052, mam708@pitt.edu
Benedict J Alter, MD, PhD, 412-677-0575, alterbj@upmc.edu
About this study
Official title: OMEGA Study: Offset Mechanisms in Evaluation of Lumbar Medial Branch Block
This study examines the relationship between central nervous system (CNS) mechanisms of pain inhibition and the pain relief that occurs following a lumbar medial branch block (MBB).
Read the detailed description
This study examines the relationship between central nervous system (CNS) mechanisms of pain inhibition and the pain relief that occurs following a commonly-performed nerve block used to diagnose and treat chronic low back pain. Patients scheduled for lumbar medial branch blocks as part of routine clinical care will arrive to clinic prior to the block for quantitative sensory testing procedures that measure CNS pain modulation. Patients will then undergo treatment as usual with their block, subsequently reporting low back pain intensity in a pain diary.
- Conditions
- Pain, Chronic, Facet Joint Pain, Pain, Procedural, Analgesia
- Being tested
- Cutaneous Probe, Quantitative Sensory Testing, Computer Tasks
- Keywords
- lumbar, medial branch block, offset analgesia, onset hyperalgesia, QST, quantitative sensory testing
- Medical subject headings
- Chronic Pain, Pain, Procedural, Agnosia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Cutaneous ProbeBehavioural
A computer-controlled probe delivers temperatures to the skin to measure pain, offset analgesia and onset hyperalgesia.
Quantitative Sensory TestingBehavioural
Standard methods involving pinprick, pressure, heat, and cold applied to the skin are used to measure sensation and pain
Computer TasksBehavioural
Quantitative Sensory Testing (QST) and computer tasks are used to measure changes in pain intensity.
| Study group | Role | What they receive |
|---|---|---|
| Quantitative Sensory Testing | Experimental | Participants with chronic low back pain and a scheduled lumbar medial branch block undergo quantitative sensory testing. Receives: Behavioral: Cutaneous Probe; Behavioral: Quantitative Sensory Testing; Behavioral: Computer Tasks |
What is being measured
The primary outcome is the main question the study is designed to answer.
Offset analgesia and onset hyperalgesia
Pain intensity difference during heat stimuli measured on a 0-100 sliding scale (0 is no pain, 100 is the most intense pain imaginable) at baseline
Measured: during this portion of the study visit (30 minutes)
Low back pain intensity change
Patients respond to the question "How would you rate your back pain right now?" from 0 (no pain) to 10 (worst imaginable pain) to see how intense their back pain is each hour after the lumbar medial branch block.
Measured: Immediately after lumbar medial branch block and up to 16 hours after lumbar medial branch block
Secondary outcomes (17)
Duration of low back pain
Participant self-reports the number of years they have experienced low back pain. The number of years for each participant will be reported.
Measured: Baseline
PEG: A Three-Item Scale Assessing Pain Intensity and Interference
Assessment for self-reported average pain and pain interference within past 7 days. Responses range from 0 (no pain) to 10 (pain as bad as you can imagine). Total scores range from 0-30, and higher scores indicate more pain interference.
Measured: Baseline
Baseline Back Pain Intensity
Assessment for determining how much a person hurts with a question ranked on a 11-point scale, from "0 = no pain" to "10 = worst imaginable pain." The minimum raw summed score is 0 and the maximum score is 10. Lower raw response scores suggest lower pain intensity and better outcomes.
Measured: Baseline
PROMIS Pain Interference 4a
Assessment for self-reported consequences of pain with 4 questions ranked on a 5-point scale, from "not at all" to "very much". The minimum raw summed score is 4 and the maximum score is 20. Lower scores suggest better outcomes.
Measured: Baseline
PROMIS Physical Function- 6b
Assessment for self-reported capability with 6 qualitatively scaled questions ranked on a 5-point scale, from "without any difficulty" to "unable to do" or "not at all" to "cannot do." The minimum raw summed score is 6 and the maximum score is 30.
Measured: Baseline
PROMIS Sleep Disturbance 6a
Assessment for self-reported perceptions of sleep quality and sleep depth with 6 questions ranked on a 5-point scale. The minimum raw summed score is 6 and the maximum score is 30. Lower scores suggest better outcomes.
Measured: Baseline
6-item Pain Catastrophizing Scale
Standardized survey score assessing pain perception before the study procedures begin. Rumination subscale score ranges from 0-16. Magnification subscale score ranges 0-12. Helplessness subscale score ranges from 0-24. Total score can be calculated by summing subscales. Total score ranges from 0-52, with higher scores indicating more pain catastrophizing.
Measured: Baseline
Patient Health Questionnaire (PHQ-2)
The PHQ-2 inquires about the frequency of depressed mood and anhedonia over the past two weeks. The PHQ-2 includes the first two items of the PHQ-9. A PHQ-2 score ranges from 0-6. The authors identified a score of 3 as the optimal cutpoint when using the PHQ-2 to screen for depression.
If the score is 3 or greater, major depressive disorder is likely.
Measured: Baseline
PROMIS 4-item Depression
Assessment for self-reported negative mood and views of self with 4 questions ranked on a 5-point scale, from "never" to "always". The minimum raw summed score is 4 and the maximum score is 20. Lower t-scores suggest better outcomes.
Measured: Baseline
PROMIS 4-item Anxiety
Assessment for self-reported fear, anxious misery, hyperarousal, and somatic symptoms with 4 questions ranked on a 5-point scale, from "never" to "always". The minimum raw summed score is 4 and the maximum score is 20. Lower scores suggest better outcomes.
Measured: Baseline
Areas of Pain Body Map
The digital body figure contains 36 anterior regions and 38 posterior regions on which participants can mark areas in which they experience chronic pain. The number of pain areas each participant recorded will be reported, with a possibility of 74 total regions.
Measured: Baseline
Treatment Expectancy
Assessment for the subject's expectations of treatment effec prior to lumbar medial branch block. Scores range from 0 (not at all) to 4 (very much), with total scores ranging from 0-24. Higher scores indicate higher expectations of the low back pain treatement.
Measured: Baseline
Patient Global Impression of Change
The subject's impression of the impact of the lumbar medial branch block on their pain and function will be measured with a 7-item scale (1 = very much worse, 2 = much worse, 3 = minimally worse, 4 = no change, 5 = minimally improved, 6 = much improved, 7 = very much improved).
Measured: Immediately after lumbar medial branch block
Situational pain catastrophizing scale (S-PCS)
Standardized survey score assessing pain perception immediately following the lumbar medial branch block. Scores range from 0-24, with higher scores representing more pain catastrophizing.
Measured: Immediately after lumbar medial branch block
Pain intensity during QST
Changes in pain intensity during quantitative sensory tests measured on a 0-100 sliding scale (0 is no pain, 100 is the most intense pain imaginable)
Measured: during this portion of the study visit (60 minutes)
Baseline back pain intensity
Patients respond to the question "How would you rate your back pain on average?" from 0 (no pain) to 10 (worst imaginable pain) to see how intense their back pain is before the lumbar medial branch block.
Measured: baseline
Back pain intensity after lumbar medial branch block
Patients respond to the question "How would you rate your back pain right now?" from 0 (no pain) to 10 (worst imaginable pain) to see how intense their back pain is each hour after the lumbar medial branch block.
Measured: Immediately after lumbar medial branch block and up to 16 hours after lumbar medial branch block
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Jul 2023
- Study start5 Jul 2023
- Primary completionJun 2028 (estimated)
- Study completionJun 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Pain, ChronicStudies of the same condition, open and under way.
- More trials run by University of PittsburghThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Quantitative Sensory Testing
- Masking
- None (open label)
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Pittsburgh
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Benedict Alter, University of Pittsburgh
- Investigators
- Benedict J Alter, MD, PhD, Principal investigator, University of Pittsburgh
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05961800
- Sponsor's protocol ID
- STUDY23040122
- Acronym
- OMEGA
- Status last verified
- Jul 2026
- First submitted
- 5 Jul 2023
- Last updated
- 27 Jul 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Individual participant data will be available, including data dictionaries, after publication per journal and funding protocols. The statistical analysis plan and analytic code will also be available per the same protocols.
Study at a glance
From the registry record, last updated by the sponsor on 27 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- OMEGA Study: Offset Mechanisms in Evaluation of Lumbar Medial Branch Block
- ClinicalTrials.gov ID
- NCT05961800
- Acronym / sponsor ID
- OMEGA / STUDY23040122
- Conditions
- Pain, Chronic, Facet Joint Pain, Pain, Procedural, Analgesia
- Keywords
- lumbar, medial branch block, offset analgesia, onset hyperalgesia, QST, quantitative sensory testing
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- University of PittsburghUniversity, hospital or other
- Study start
- 5 Jul 2023 (actual)
- Primary completion
- Jun 2028 (estimated)
- Study completion
- Jun 2028 (estimated)
- First posted
- 27 Jul 2023 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study examines the relationship between central nervous system (CNS) mechanisms of pain inhibition and the pain relief that occurs following a lumbar medial branch block (MBB).
Detailed description
This study examines the relationship between central nervous system (CNS) mechanisms of pain inhibition and the pain relief that occurs following a commonly-performed nerve block used to diagnose and treat chronic low back pain. Patients scheduled for lumbar medial branch blocks as part of routine clinical care will arrive to clinic prior to the block for quantitative sensory testing procedures that measure CNS pain modulation. Patients will then undergo treatment as usual with their block, subsequently reporting low back pain intensity in a pain diary.
Study design
- Primary purpose
- Basic science
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Quantitative Sensory Testing
| Arm | Type | Receives |
|---|---|---|
| Quantitative Sensory Testing | Experimental | Behavioral: Cutaneous Probe, Behavioral: Quantitative Sensory Testing, Behavioral: Computer TasksParticipants with chronic low back pain and a scheduled lumbar medial branch block undergo quantitative sensory testing. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Scheduled for lumbar MBB in UPMC Pain Management clinics
- Age > 18 years old
- Predominantly axial chronic low back pain at least 3 months on a daily basis
- Must meet the minimum criteria for cognitive function using the PROMIS 2-item cognitive screener (>3)
- Low back pain intensity of > 3/10
Key exclusion criteria (5 listed)
- History of spine surgery at the level of the lumbar MBB
- Active worker's compensation or litigation claims
- New pain and/or psychiatric treatments within 2 weeks of enrollment
- Not fluent in English and/or not able to complete the questionnaires
- Any clinically unstable systemic illness that is judged to interfere with the study
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Cutaneous ProbeA computer-controlled probe delivers temperatures to the skin to measure pain, offset analgesia and onset hyperalgesia. | Behavioural | Quantitative Sensory Testing |
| Quantitative Sensory TestingStandard methods involving pinprick, pressure, heat, and cold applied to the skin are used to measure sensation and pain | Behavioural | Quantitative Sensory Testing |
| Computer TasksQuantitative Sensory Testing (QST) and computer tasks are used to measure changes in pain intensity. | Behavioural | Quantitative Sensory Testing |
Primary outcome
Offset analgesia and onset hyperalgesia
Time frame: during this portion of the study visit (30 minutes)
Pain intensity difference during heat stimuli measured on a 0-100 sliding scale (0 is no pain, 100 is the most intense pain imaginable) at baseline
Low back pain intensity change
Time frame: Immediately after lumbar medial branch block and up to 16 hours after lumbar medial branch block
Patients respond to the question "How would you rate your back pain right now?" from 0 (no pain) to 10 (worst imaginable pain) to see how intense their back pain is each hour after the lumbar medial branch block.
17 secondary outcomes
Duration of low back pain
Time frame: Baseline
PEG: A Three-Item Scale Assessing Pain Intensity and Interference
Time frame: Baseline
Baseline Back Pain Intensity
Time frame: Baseline
PROMIS Pain Interference 4a
Time frame: Baseline
PROMIS Physical Function- 6b
Time frame: Baseline
PROMIS Sleep Disturbance 6a
Time frame: Baseline
6-item Pain Catastrophizing Scale
Time frame: Baseline
Patient Health Questionnaire (PHQ-2)
Time frame: Baseline
PROMIS 4-item Depression
Time frame: Baseline
PROMIS 4-item Anxiety
Time frame: Baseline
Areas of Pain Body Map
Time frame: Baseline
Treatment Expectancy
Time frame: Baseline
Patient Global Impression of Change
Time frame: Immediately after lumbar medial branch block
Situational pain catastrophizing scale (S-PCS)
Time frame: Immediately after lumbar medial branch block
Pain intensity during QST
Time frame: during this portion of the study visit (60 minutes)
Baseline back pain intensity
Time frame: baseline
Back pain intensity after lumbar medial branch block
Time frame: Immediately after lumbar medial branch block and up to 16 hours after lumbar medial branch block
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Jul 2026.
- Individual participant dataSharing planned: Yes. Individual participant data will be available, including data dictionaries, after publication per journal and funding protocols. The statistical analysis plan and analytic code will also be available per the same protocols.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Benedict J Alter, MD, PhD principal investigator
University of Pittsburgh
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Cutaneous Probe, Quantitative Sensory Testing and Computer Tasks in people with Pain, Chronic and Facet Joint Pain, run by University of Pittsburgh at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 27 Jul 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Maya L Maurer, BS (412-665-8052, mam708@pitt.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Offset analgesia and onset hyperalgesia (time frame: during this portion of the study visit (30 minutes)). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Jul 2026.