Interventional Pain Procedures

Diagnostic blocks are a critical investigative step in interventional pain medicine. While advanced imaging such as MRI or CT scans can identify anatomical irregularities, scans cannot always prove which specific structure is actively generating pain. A diagnostic block involves placing a small amount of local anaesthetic directly onto or adjacent to a suspected nerve or joint under precise image guidance (ultrasound or fluoroscopy).

By temporarily numbing the target structure, your pain specialist can assess immediate changes in your pain levels and daily mobility during the hours following the procedure. You will often be asked to keep a temporary pain diary. If your familiar pain is significantly reduced while the local anaesthetic is active, it confirms that the target is a primary pain generator. This allows us to design targeted, long-lasting interventions—such as radiofrequency ablation—with high clinical confidence.

Targeted corticosteroid injections—including epidural steroid injections (transforaminal or interlaminar) and intra-articular injections—deliver a concentrated anti-inflammatory agent directly to the site of tissue irritation. Unlike oral medications that circulate throughout the entire body, targeted local delivery achieves high local anti-inflammatory efficacy while minimising systemic side effects.

These injections are frequently used to treat inflamed spinal nerve roots (such as in disc herniations or sciatica) or inflamed joints. While local anaesthetic provides immediate but temporary relief, the corticosteroid begins working over several days to reduce tissue swelling and nerve hyper-reactivity. The goal of this treatment is not only symptom reduction, but also opening an essential "rehabilitation window"—allowing you to actively participate in physiotherapy and functional restoration with reduced discomfort.

Pulsed radiofrequency (PRF) is a specialised treatment that targets sections of nerves transmitting persistent pain signals to the spinal cord and brain. Under precise fluoroscopic or ultrasound guidance, a fine insulated needle is positioned adjacent to the target nerve. Rather than delivering continuous heat (which creates a thermal lesion), the pulsed RF generator delivers rapid bursts of high-frequency electrical energy at temperatures typically kept below 42°C.

The science behind PRF is neuromodulation: the electrical field alters cell membrane potentials and disrupts abnormal pain signalling pathways without physically damaging or destroying the nerve structure. Because structural integrity is preserved, PRF is particularly suitable for mixed sensory-motor nerves and carries minimal risk of motor weakness or sensory numbness. Many patients experience substantial relief lasting from 3 to 12 months, and the procedure can be safely repeated if necessary.

Thermal radiofrequency ablation (also known as RF neurotomy or rhizotomy) is an established procedure for managing persistent spinal pain arising from arthritic facet joints or the sacroiliac joint. It is typically recommended only after successful diagnostic blocks have confirmed that those specific joints are responsible for your symptoms.

During the procedure, performed under local anaesthesia with light sedation and real-time X-ray guidance, an insulated radiofrequency electrode is positioned alongside the small sensory nerves (the medial branches) that supply the painful joint. A controlled thermal current (typically 80°C–85°C) is applied for 60 to 90 seconds, gently disrupting the nerve fibres' ability to conduct pain sensations. Because the medial branch nerves only transmit sensory pain signals from the joint and do not control muscle strength in the limbs, motor function remains intact. Relief typically lasts between 6 and 18 months until the microscopic nerve endings regenerate, at which point the treatment can be repeated if indicated.

Chemical neurolysis is an advanced interventional technique utilised primarily for severe, intractable pain—most commonly in cancer-related visceral pain syndromes, complex regional pain syndrome (CRPS), or refractory vascular pain. In this procedure, specialised neurolytic agents (such as pharmaceutical-grade dehydrated ethanol or aqueous phenol) are carefully injected around deep autonomic nerve plexuses or peripheral sensory pathways.

The neurolytic chemical disrupts pain transmission across targeted autonomic plexuses—such as the celiac plexus (for upper abdominal and pancreatic pain), the superior hypogastric plexus (for pelvic pain), or the ganglion impar (for perineal pain). Prior to any neurolysis, a diagnostic prognostic block using local anaesthetic is performed to verify efficacy and safety. By interrupting persistent sympathetic and visceral pain signals, neurolysis can significantly reduce high-dose opioid requirements, improve sleep, and alleviate debilitating gastrointestinal or pelvic distress.

Spinal Cord Stimulation (SCS) is an advanced medical treatment for severe, chronic neuropathic pain that has not responded adequately to conservative therapies, surgery, or routine interventional injections. Often referred to as a "pacemaker for pain," SCS delivers gentle, finely tuned electrical micro-pulses to the dorsal columns of the spinal cord, masking or altering pain signals before they reach the brain.

A hallmark benefit of SCS is that it is completely testable and reversible through a two-stage process. The Temporary Trial (5–10 days): Under mild sedation and local anaesthesia, thin, flexible leads are guided into the epidural space via a needle. The leads connect to an external stimulator worn on a belt. During this trial period at home, you test the therapy in real-world everyday activities. A trial is considered successful if it achieves a clinically significant reduction in pain (typically ≥50%), alongside measurable improvements in sleep, function, and reduction in pain medication. Permanent Implantation: If and only if the trial is successful and you choose to proceed, the system is fully internalised under the skin. Modern systems feature rechargeable or long-life non-rechargeable batteries, multiple waveform modes (including paresthesia-free/sub-perception high-frequency or burst stimulation, and closed-loop technologies), and smartphone or handheld programming.