Before You Intervene: Assess the Mechanism, Mind and Nociplastic Pain

Interventional pain medicine is a technically demanding specialty.

Pain physicians must learn anatomy, interpret imaging, identify pain-generating structures and place needles accurately under ultrasound or fluoroscopic guidance. They must understand injectates, radiofrequency technology, neuromodulation, orthobiologics and procedural safety.

These skills require years of training and disciplined practice. Technical competence remains essential.

But it is no longer enough.

A technically perfect procedure can still produce a poor result when:

• The diagnosis is incorrect.
• The abnormality on imaging is incidental.
• The wrong pain mechanism has been targeted.
• The patient has an important nociplastic component.
• Major depression, severe anxiety, trauma, substance misuse or another psychiatric disorder has not been identified.
• Expectations are unrealistic.
• Rehabilitation has not been planned.
• Follow-up and outcome measurement are inadequate.

The central lesson is straightforward:

Procedural accuracy is only one component of clinical success.

Modern pain medicine requires the physician to integrate diagnosis, pain-mechanism assessment, psychological and psychiatric evaluation, patient selection, evidence, intervention, rehabilitation and longitudinal follow-up into one coherent treatment pathway.

The First Responsibility Is Not to Find a Procedure

When patients arrive at an interventional pain clinic, they often carry MRI reports showing disc bulges, degeneration, osteoarthritis, tendon abnormalities or nerve compression.

These findings may be clinically relevant. They may also be incidental.

The presence of an abnormality does not prove that it is the primary source of the patient’s pain. Structural changes are common, particularly with ageing, and the severity of imaging findings does not always correlate with pain intensity or disability.

The first responsibility of the pain physician is therefore not to identify which procedure can be performed.

It is to determine:

• What is causing or maintaining the pain?
• Is there a serious underlying disease?
• Does the clinical presentation correspond with the imaging?
• What pain mechanisms are involved?
• Are biological, psychological and social factors amplifying the presentation?
• Is an intervention necessary?
• Is the patient an appropriate candidate for it?

A procedure should follow a diagnosis and a mechanistic assessment. The diagnosis should not be created to justify the procedure.

Pain Must Be Classified by Mechanism

Before selecting an intervention, the physician should consider whether the pain is predominantly:

Nociceptive

Pain arising from actual or threatened damage to non-neural tissue, such as osteoarthritis, tendinopathy, inflammation or mechanical tissue overload.

Neuropathic

Pain caused by a lesion or disease of the somatosensory nervous system, such as radiculopathy, post-herpetic neuralgia or painful peripheral neuropathy.

Nociplastic

Pain arising from altered nociception when the pain cannot be adequately explained by tissue damage activating peripheral nociceptors or by a lesion or disease of the somatosensory nervous system.

These mechanisms are not mutually exclusive.

A patient may have knee osteoarthritis producing nociceptive pain while also developing widespread hypersensitivity, sleep disturbance, fatigue and altered central pain processing. Another patient may have a genuine lumbar radiculopathy together with a significant nociplastic component.

IASP specifically recognises that nociceptive and nociplastic mechanisms may coexist.

This distinction is important because a peripheral intervention may successfully treat one pain generator without adequately treating the patient’s complete pain experience.

Nociplastic Pain Must Be Considered Before Repeated Interventions

One of the most important developments in contemporary pain medicine is the recognition of nociplastic pain.

Possible clinical features include:

• Pain that is more widespread or intense than expected from the identifiable tissue abnormality
• Multiple painful areas
• Allodynia or hyperalgesia
• Pain persisting beyond expected tissue healing
• Disproportionate symptom severity
• Fatigue
• Poor or non-restorative sleep
• Cognitive complaints
• Sensitivity to sound, light, touch or temperature
• Variable symptoms and recurrent flares
• Coexisting headache, irritable bowel symptoms or other functional somatic symptoms

The proposed clinical criteria for musculoskeletal nociplastic pain include chronic regional pain and evoked pain hypersensitivity. Additional features supporting probable nociplastic pain include hypersensitivity to normally non-painful stimuli, sleep disturbance, fatigue, cognitive difficulties and other sensory hypersensitivities.

Recognising nociplastic pain does not mean that the pain is imaginary. It does not mean that the patient has no structural pathology. It also does not mean that all interventions are inappropriate.

It means that altered pain processing may be contributing significantly to the presentation.

In such patients, repeatedly targeting peripheral structures without addressing sleep, activity, psychological distress, sensitisation, deconditioning and self-management may produce incomplete or short-lived benefits.

Before repeating injections or escalating to more invasive treatment, the physician should therefore ask:

Is the procedure failing because the target is incorrect, or because the patient’s pain is no longer maintained predominantly by that peripheral target?

This question can prevent unnecessary procedures and help direct the patient towards more appropriate multimodal care.

Psychological Assessment Is a Clinical Requirement

Pain is not purely a sensory event. It affects—and is affected by—sleep, mood, behaviour, relationships, work, trauma, beliefs, fear and social circumstances.

NICE recommends a person-centred chronic-pain assessment that explores psychological wellbeing, stressful life events, physical or emotional trauma, sleep disturbance, substance misuse, social relationships and employment or financial concerns.

This does not imply that pain is “all psychological.”

Psychological assessment has two different purposes.

First, it identifies common factors that can amplify pain and disability, including:

• Fear of movement
• Catastrophising
• Hypervigilance
• Low self-efficacy
• Avoidance behaviour
• Poor coping
• Health anxiety
• Disturbed sleep
• Unresolved trauma
• Unrealistic expectations

Second, it identifies major psychiatric disorders or safety concerns that require specific attention before an elective intervention.

These may include:

• Major depressive disorder
• Suicidal thoughts or recent self-harm
• Severe uncontrolled anxiety or panic disorder
• Psychosis
• Mania
• Severe post-traumatic stress disorder
• Active substance-use disorder
• Significant cognitive impairment
• Severe personality-related instability affecting consent, adherence or safety

Depression is particularly relevant in people living with chronic physical conditions and should be recognised and managed rather than overlooked.

What Does “Ruling Out” a Major Psychiatric Disorder Mean?

It does not mean that every patient requires a formal psychiatric consultation before a pain procedure.

It means that the pain physician should perform an appropriate clinical screen and recognise when further psychological or psychiatric evaluation is necessary.

The consultation should explore:

• Mood and loss of interest
• Sleep and appetite
• Anxiety and panic symptoms
• Previous trauma
• Substance and medication use
• Thoughts of hopelessness or self-harm
• The patient’s understanding of the condition
• Expectations from the procedure
• Ability to provide informed consent
• Ability to participate in rehabilitation and follow-up

Validated screening instruments may supplement the clinical interview, but they do not replace it.

When there is active suicidality, uncontrolled psychosis, mania, severe substance misuse or another acute psychiatric safety concern, elective interventional treatment may need to be postponed while urgent psychiatric care is arranged.

In other cases, the procedure may still be appropriate, but psychological or psychiatric treatment should occur concurrently.

The objective is not to exclude patients with mental-health conditions from pain treatment. It is to provide safer, more realistic and more effective care.

Avoid Two Opposite Clinical Errors

Pain physicians must avoid two equally harmful mistakes.

Error 1: Psychologising the patient’s pain

Statements such as “Your tests are normal, so the pain must be psychological” can invalidate the patient and damage the therapeutic relationship.

Normal imaging does not mean that pain is unreal. Nociplastic pain is a legitimate pain mechanism, not a synonym for malingering, exaggeration or psychiatric illness.

Error 2: Ignoring psychological and psychiatric factors

The opposite error is to treat pain as a purely anatomical problem and continue performing interventions without assessing depression, trauma, fear, substance misuse or maladaptive coping.

Psychological distress can influence:

• Pain intensity
• Disability
• Treatment expectations
• Adherence
• Participation in rehabilitation
• Interpretation of procedural outcomes
• Overall quality of life

A comprehensive assessment acknowledges both realities:

The pain is real, and psychological or psychiatric factors may still influence how the pain is experienced, maintained and treated.

The Procedure Must Follow the Diagnosis

A technically skilled physician asks:

“Can I perform this procedure safely?”

A clinically mature physician first asks:

“Should this procedure be performed in this patient?”

Before choosing an intervention, the physician must determine:

• What is the most probable pain generator?
• Is the imaging abnormality clinically concordant?
• Is the pain nociceptive, neuropathic, nociplastic or mixed?
• Are there multiple pain generators?
• Is a major psychiatric disorder affecting safety or treatment readiness?
• Is there a substance-use problem?
• What is the patient’s principal functional limitation?
• What does the patient expect the procedure to achieve?
• Is there a realistic rehabilitation plan?
• What will constitute a successful outcome?

This distinction separates procedure-driven practice from diagnosis-driven pain medicine.

In procedure-driven practice, the available technique begins to influence the diagnosis:

“I perform epidural injections, so this patient may need an epidural.”

In diagnosis-driven practice, the clinical problem determines the treatment:

“This patient has a particular combination of pain generators, mechanisms and psychosocial contributors. Which treatment pathway is most appropriate?”

The second approach may still result in an injection, radiofrequency treatment, neuromodulation, orthobiological intervention or surgery. But the intervention becomes one component of a reasoned treatment strategy.

Patient Selection Determines Much of the Outcome

An evidence-supported procedure does not work equally well for every patient.

Success depends on selecting patients whose diagnosis, dominant pain mechanism, disease stage, psychological readiness, expectations and functional goals correspond with the proposed treatment.

Before an elective intervention, the physician should consider:

• Is there clinical concordance between history, examination and investigation?
• Is a nociplastic mechanism likely to dominate the presentation?
• Is severe psychological distress likely to interfere with recovery?
• Are expectations realistic?
• Have appropriate non-interventional treatments been attempted?
• Are there modifiable biomechanical or lifestyle contributors?
• Does the patient understand the probable benefits and limitations?
• Will the patient participate in rehabilitation?
• How will improvement be measured?

Patient selection is more than excluding infection, coagulopathy or medical contraindications.

It is the process of determining whether a specific treatment is likely to help a specific patient achieve a specific, meaningful goal.

The Treatment Goal Must Be Defined Before the Procedure

Success should not be defined solely by a pain score.

A treatment may be valuable when it allows the patient to:

• Walk farther
• Return to work
• Sleep better
• Reduce analgesic consumption
• Participate in physiotherapy
• Resume exercise
• Care for family members
• Improve independence
• Reduce recurrent emergency visits

A reduction from 8/10 to 4/10 may be meaningful if function improves substantially.

Conversely, temporary pain reduction may have limited value if the patient remains inactive, distressed, medication-dependent and unable to resume normal activity.

Defining goals before treatment also reduces the risk of repeating procedures merely because the result was “partially helpful.”

A Procedure Should Create a Window for Rehabilitation

Pain relief is often not the final destination. It creates an opportunity.

A patient with severe knee pain may be unable to strengthen the quadriceps. A patient with radicular pain may avoid walking. A patient with shoulder pain may progressively lose movement because exercise is painful.

An intervention may reduce pain sufficiently to allow movement, graded exercise and restoration of function.

But the window can close.

Without a rehabilitation plan, the patient may return to the same weakness, deconditioning, overload, fear and avoidance that contributed to the disability.

For patients with significant nociplastic pain, rehabilitation may also require:

• Pain neuroscience education
• Graded exposure
• Pacing
• Sleep optimisation
• Cognitive behavioural approaches
• Acceptance and commitment therapy
• Psychological support
• Gradual restoration of meaningful activity

NICE recommends exercise and recognises the role of cognitive behavioural therapy and acceptance and commitment therapy in chronic primary pain.

WHO similarly promotes integrated, person-centred management of chronic primary low-back pain, involving education, exercise, selected physical therapies and psychological interventions rather than reliance on one isolated treatment.

Evidence Must Guide Clinical Judgement

Pain medicine is evolving rapidly. New biological preparations, devices, imaging technologies and interventions are continuously introduced.

Innovation is essential, but novelty is not equivalent to evidence.

Before recommending a treatment, clinicians should examine:

• Biological plausibility
• Quality of the supporting studies
• Relevance of the study population
• Magnitude and duration of benefit
• Patient-selection criteria
• Complication rates
• Financial cost
• Reasonable alternatives
• Areas of uncertainty

Evidence-based practice combines the best available research with clinical expertise and the patient’s goals, values and circumstances.

It also requires honesty.

Some treatments have strong evidence for specific indications. Others have emerging or uncertain evidence. Some may help only carefully selected subgroups.

The quality of pain practice is measured not only by what a physician can perform, but also by what the physician appropriately decides not to perform.

Follow-Up Is Part of the Intervention

A procedure does not end when the needle is removed.

Follow-up should evaluate:

• Pain intensity
• Function
• Sleep
• Activity
• Analgesic use
• Participation in rehabilitation
• Psychological wellbeing
• Duration of benefit
• Adverse events
• Progress towards the agreed goal

Follow-up is particularly important when nociplastic or psychological factors are present. A patient may report persistent pain but demonstrate major functional improvement. Another may report transient pain relief without any improvement in activity or quality of life.

Without structured follow-up, neither the physician nor the patient can determine whether the treatment delivered meaningful benefit.

A Better Pre-Intervention Framework

Before every elective intervention, the pain physician should ask ten questions.

1. Have serious causes or red flags been excluded?

Consider infection, malignancy, fracture, inflammatory disease, progressive neurological deficit and other clinical red flags.

2. What is the most probable diagnosis?

Establish clinical concordance between the history, examination and relevant investigations.

3. What pain mechanisms are operating?

Assess for nociceptive, neuropathic and nociplastic mechanisms, recognising that they may coexist.

4. Is there a major psychological concern?

Screen for severe depression, suicidality, psychosis, mania, trauma, substance misuse and other factors affecting safety or readiness.

5. Is the proposed target responsible for a meaningful proportion of the pain?

Avoid treating an imaging abnormality without adequate clinical correlation.

6. Why is this patient suitable for the intervention?

Identify the factors that predict a reasonable possibility of benefit.

7. What is the treatment objective?

Define a functional and measurable goal, not merely an anticipated percentage reduction in pain.

8. What does the evidence show?

Discuss expected benefit, duration, alternatives, risks and uncertainty.

9. What happens after the procedure?

Integrate medication management, rehabilitation, psychological support and graded activity.

10. How and when will success be measured?

Arrange structured follow-up and document outcomes meaningful to the patient.

The Future Belongs to the Complete Pain Physician

Technical excellence still matters.

Poor procedural execution can cause treatment failure, diagnostic confusion and avoidable complications. Image guidance, anatomical knowledge, sterile technique, appropriate equipment and procedural discipline remain foundational.

But technical excellence should serve clinical reasoning—not replace it.

The complete pain physician must know:

• When to intervene
• When not to intervene
• Which pain mechanism is dominant
• When nociplastic pain is contributing
• When psychological support is required
• When psychiatric referral is necessary
• Which anatomical target is clinically relevant
• What evidence supports the treatment
• How rehabilitation will be integrated
• How the outcome will be measured

The future pain physician is not merely a proceduralist.

The physician is also a diagnostician, pain-mechanism interpreter, communicator, psychological-risk screener, collaborator, evidence appraiser and longitudinal-care provider.

Technical skill may place the needle exactly where it was intended.

Clinical wisdom determines whether the target is responsible for the pain, whether the patient is psychologically and medically ready, whether nociplastic mechanisms are likely to limit the response, what should happen after the intervention and whether the treatment genuinely improves the patient’s life.

That is the difference between performing a procedure and practising comprehensive pain medicine.

References

1. International Association for the Study of Pain. IASP Terminology: Nociceptive, neuropathic and nociplastic pain.
2. National Institute for Health and Care Excellence. Chronic pain in over 16s: assessment of all chronic pain and management of chronic primary pain. NICE Guideline NG193.
3. Kosek E, Clauw D, Nijs J, et al. Chronic nociplastic pain affecting the musculoskeletal system: clinical criteria and grading system. Pain. 2021;162:2629–2634.
4. Yoo YM, Kim KH. Current understanding of nociplastic pain. Korean Journal of Pain. 2024.
5. World Health Organization. WHO guideline for non-surgical management of chronic primary low-back pain in adults in primary and community care settings. 2023.
6. National Institute for Health and Care Excellence. Depression in adults with a chronic physical health problem: recognition and management.
7. Das G, Das S, Amatya SP, Hota SR, Poudel H, Milton AH. Why pain physicians must actively look for nociplastic pain? The Daradia Protocol. Journal on Musculoskeletal Ultrasound and Pain Medicine. 2025;10:5–10. doi: 10.4103/jmupm.jmupm_33_25.