⚙️ Rethinking Chronic Pain: A Neurophysiological Perspective
The traditional view that chronic pain stems solely from structural damage is no longer sufficient. Advances in neuroscience reveal that persistent dysfunction in the peripheral and central nervous systems often underlies chronic pain—even in the absence of visible injury.
Key contributors include:
- Peripheral neuroinflammation, caused by ischemia, compression, or metabolic stress, leads to sustained release of substances like Substance P and CGRP.
- Peripheral sensitization, where nerves lower their activation threshold, resulting in exaggerated pain responses such as allodynia and hyperalgesia.
- Autonomic-sensory feedback loops, where inflammation induces local vasodilation, trophic skin changes, and prolonged sympathetic activation.
The Perineural Matrix: A Dynamic Sensory Interface
This matrix—composed of sensory nerve endings, glial cells, immune mediators, and connective tissue—is far from passive. It actively modulates pain and, when disrupted, becomes a source of pain generation on its own, regardless of tissue integrity.
🧬 What is Perineural Injection Therapy (PIT)?
Composition
PIT uses buffered 5% dextrose (D5W), a safe, isotonic, and pH-balanced solution. Unlike corticosteroids or anesthetics, D5W offers:
- Inhibition of proinflammatory neuropeptides
- Downregulation of TRPV1 channels
- Osmotic modulation of the perineural environment
This results in anti-inflammatory and pro-regenerative effects with minimal risk.
Application
- Targeting: Painful superficial nerves are identified through palpation and/or ultrasound.
- Technique: Microinjections (low volume) are delivered subcutaneously, adjacent to nerves.
- Treatment Plan: Typically 5–20 injection points per session, 1–2 times per week for 4–6 weeks. Follow-up sessions are spaced 2–4 weeks apart based on clinical progress.
Biological Action
PIT reduces abnormal nerve excitability, calms neurogenic inflammation, promotes axonal healing, and supports cortical desensitization.
📊 Clinical Outcomes
Emerging evidence and case data indicate high efficacy in various conditions:
- Post-surgical neuralgia: Over 70% of patients report a 50% or greater reduction in pain (VAS) within 4–6 sessions.
- Diabetic neuropathy: Marked improvement in burning, tingling, and numbness, with better DN4 scores.
- CRPS: Reductions in pain, edema, and autonomic symptoms.
- TMJ dysfunction: Fewer pain episodes and improved mandibular mobility after just a few treatments.
🛠️ Indications
PIT is especially effective for:
- Peripheral neuropathies (diabetic, idiopathic)
- Postoperative neural entrapments
- Complex Regional Pain Syndrome (CRPS)
- Thoracic Outlet Syndrome
- Neurogenic TMJ dysfunction
- Myofascial pain with neural involvement
🔄 Multimodal Neurofunctional Integration
PIT reaches its full potential when combined with complementary therapies:
- AIMS (Assessment of Integrated Movement System): Detects and addresses neuromotor dysfunction post-sensitization.
- LLLT (Low-Level Laser Therapy): Enhances ATP production and promotes nerve recovery.
- ESWT (Shock Wave Therapy): Breaks chronic pain cycles and improves blood flow.
- TECAR and Cryotherapy: Accelerate inflammatory resolution and tissue metabolism.
- EMTT (Electromagnetic Transduction Therapy): Restores axonal communication and electrical balance.
🧾 Safety and Contraindications
Safety
- Non-pharmacological
- Minimal systemic absorption
- Well-tolerated with low complication rates
- Requires only brief post-procedure rest (1–2 hours)
Contraindications
Absolute:
- Active infections
- Severe thrombocytopenia
- Allergy to dextrose
- Uncontrolled sensory neuropathies
Relative:
- Recent chemotherapy
- Pregnancy (case-by-case approval)
- Genetic neuropathies during acute flares
📈 Expected Results
Short-Term
- Pain relief within 48–72 hours
- Decreased allodynia
- Improved temperature regulation and edema
Medium-Term
- Restored function (walking, grip, jaw motion)
- Reduced reliance on analgesics
- Enhanced quality of life
Long-Term
- Neurological stability
- Lower recurrence rates
- Return to sleep, work, and exercise routines.
✅ Final Thoughts
Perineural Injection Therapy is redefining how we treat chronic pain. Rather than masking symptoms, PIT modulates the neural matrix and restores the body’s pain perception at its source.
When integrated into a neurofunctional care model, PIT empowers providers to not only manage pain—but transform patient outcomes through recovery, regulation, and long-term relief.