Trigger Point Injections
Trigger point injections are used to treat myofascial pain caused by hyperirritable knots within muscle bands that produce referred pain. They involve the injection of a small amount of local anaesthetic, sometimes combined with corticosteroid, directly into the trigger point. This can relieve muscle spasm, improve mobility, and break the pain–spasm cycle. The procedure is minimally invasive and usually performed in the outpatient setting. Dry needling (without injectate) may also be effective in selected patients. Post-injection stretching and physiotherapy enhance long-term benefit.
Botox (Botulinum Toxin) Injections
Botulinum toxin type A injections provide analgesia through neuromuscular blockade and inhibition of acetylcholine release, resulting in muscle relaxation and reduced abnormal pain signalling. They are indicated for chronic migraine, spasticity, dystonia, and focal myofascial pain. Pain relief typically develops over several days and lasts for 3–4 months. Repeat injections may be required. Side effects are usually mild and localised (e.g. transient weakness, injection site pain). Procedures should be performed by clinicians experienced in anatomical localisation and dosage titration.
Specific Nerve Injections
These injections target individual peripheral nerves responsible for transmitting pain from a particular area (e.g. occipital nerve, intercostal nerve, genicular nerve). The injectate may include local anaesthetic, corticosteroid, or neurolytic agents, depending on the clinical aim (diagnostic, therapeutic, or ablative). They are used for neuropathic pain, post-surgical neuralgia, or regional musculoskeletal pain. Nerve injections can be diagnostic — confirming pain origin — or therapeutic, providing sustained relief when inflammation or irritation is present. Image guidance (ultrasound or fluoroscopy) improves accuracy and safety.
Nerve Plexus Injections
These injections target larger nerve plexuses supplying organs or regions, such as the brachial, lumbar, or lumbosacral plexus, providing broader regional anaesthesia or pain control. Common indications include cancer-related pain, postoperative pain, or limb pain syndromes. Local anaesthetic with or without steroid is used for temporary relief, while neurolytic agents (e.g. phenol or alcohol) may be considered for chronic malignant pain. Ultrasound or fluoroscopic guidance ensures safe and accurate placement, reducing complications such as vascular or nerve injury.
Sympathetic Nerve Plexus Injections
These target components of the autonomic nervous system involved in maintaining chronic pain states, such as the stellate ganglion, celiac plexus, or lumbar sympathetic chain. They are particularly effective for complex regional pain syndrome (CRPS), ischemic limb pain, and visceral cancer pain. The goal is to interrupt sympathetic efferent signalling and restore normal blood flow and temperature regulation. Diagnostic blocks with local anaesthetic are performed first, followed by longer-acting or neurolytic blocks if effective. Image guidance is essential due to proximity to major vessels.
Epidural Injections
Epidural steroid injections deliver corticosteroid and local anaesthetic into the epidural space surrounding the spinal cord to reduce inflammation of nerve roots. They are commonly used for radicular pain (sciatica), spinal stenosis, and disc herniation. Approaches include interlaminar, transforaminal, or caudal routes depending on pathology location. Pain relief may last weeks to months and can facilitate engagement in rehabilitation. Risks include headache, bleeding, infection, or transient neurological symptoms, and the procedure should be performed under image guidance in appropriate sterile conditions.
Facet Joint and Medial Branch Blocks
Facet joint injections and medial branch nerve blocks are used to diagnose and treat facet-mediated spinal pain arising from the small stabilising joints in the cervical, thoracic, or lumbar spine. Local anaesthetic (with or without corticosteroid) is injected into the joint capsule or around the medial branch nerves supplying the facet joints. If diagnostic blocks provide temporary relief, longer-term denervation using radiofrequency neurotomy may be offered. These procedures can reduce axial back or neck pain and improve functional mobility.
Pulsed Radiofrequency and Radiofrequency Neurotomy
Radiofrequency (RF) procedures apply targeted thermal or pulsed electromagnetic energy to interrupt pain transmission in specific nerves. Pulsed RF delivers intermittent bursts at lower temperatures (around 42°C), modulating nerve function without destruction — suitable for neuropathic or mixed pain syndromes. Conventional RF (neurotomy) ablates the sensory nerve fibres at 80–90°C, providing longer-term relief in well-localised pain sources (e.g. facet joint pain). Both are minimally invasive, image-guided procedures, often performed after successful diagnostic blocks.
Neuromodulation (Peripheral Field, Peripheral Nerve, and Spinal Cord Stimulation)
Neuromodulation therapies deliver mild electrical impulses to modulate pain signalling within the nervous system. Peripheral field stimulation (PFS) targets cutaneous regions of pain, such as post-surgical or neuropathic scars. Peripheral nerve stimulation (PNS) targets a specific named nerve (e.g. occipital, ulnar, or femoral) to reduce pain through afferent inhibition. Spinal cord stimulation (SCS) involves epidural electrode placement to modulate dorsal column activity and restore normal pain processing. Indications include failed back surgery syndrome, CRPS, neuropathic limb pain, and ischemic pain. Trial stimulation is conducted first to assess benefit before permanent implantation. Neuromodulation offers significant pain reduction, improved function, and reduced opioid dependence in selected patients.