INTERVENTIONAL PAIN MANAGEMENT DOMINICK LAGO JR., M.D. Michigan Pain Management Consultants

INTERVENTIONAL PAIN MANAGEMENT Definition: The use of invasive techniques to decrease or eliminate pain This can be accomplished in three ways: Interrupting the pain signal along a neural pathway Neuroaugmentation (SCS, PNS) Implantable drug delivery system

INJECTION THERAPY Trigger Point Injections Epidural Facet Joint/Medial Branch Block Sympathetic Chain Block

INJECTION THERAPY Usually performed utilizing fluoroscopy No sedation vs conscious sedation Can be therapeutic or diagnostic

TRIGGER POINT INJECTION Trigger points are discrete, focal, hyper- irritable spots located in a taut band of skeletal muscle The pain will be localized and or referred Palpation of a hypersensitive bundle or nodule of muscle fiber of harder than normal consistency is the physical finding typically associated with a trigger point. Palpation of the trigger point will elicit pain directly over the affected area and/or cause radiation of pain toward a zone of reference.

TRIGGER POINTS Treatment consists of release of the affected muscle or muscle groups Stretching, physical therapy and ice have been utilized

TRIGGER POINTS Injection therapy is also effective in both the acute and chronic presentations “Dry” technique Injection of local anesthetic with or without steroids

TRIGGER POINTS Injection Technique Identify the muscle via palpation Using a 25 gauge needle and 0.5% Xylocaine The needle is advance to the affected muscle A twitch response is noted and then the local is injected (3-5 cc).

EPIDURAL Injection performed to deposit medication into the epidural space in proximity to the spinal nerves Can be utilized in the cervical, thoracic or lumbar region Most effective for radicular pain into the arm or leg Should be performed with fluoroscopy

EPIDURAL There are three approaches to the epidural space Interlaminar Transforaminal Sacral Hiatus (caudal)

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EPIDURAL Interlaminar injection Performed in the midline, between the spinous processes at the affected level of pathology Medication will spread cephalad, caudad and bilaterally

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EPIDURAL Transforaminal Injection Performed lateral to the midline with a goal of depositing the medication near a specific nerve root in the neuroforamen Has a higher complication rate due to the artery of Adamkiewicz More effective for one sided, one level pathology

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EPIDURAL Caudal The epidural space is entered via the sacral hiatus Most commonly utilized if there has been a previous spine surgery

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EPIDURAL Pain conditions that may respond to epidural steroid injections Herniated disc Spinal stenosis Post laminectomy syndrome Spondylosis Complex r

EPIDURAL Pain conditions that may respond to epidural injections with local anesthetic Diabetic Neuropathy Complex Regional Pain Syndrome (RSD) Post Herpetic Neuralgia

EPIDURAL ESI, how does it work? When the spinal nerve is inflamed it becomes edematous. As it travels through the neuroforamen it becomes “pinched” which maintains the inflammation. After the steroids are injected, they reduce the inflammation, decreasing the diameter of the nerve, giving it more room in the foramen.

EPIDURAL These injections may be repeated, but limited to three within six months. Long term success is based on a multi- disciplinary approach, not just injection therapy

EPIDURAL Sympathetic epidural injection is utilized for neuropathic pain syndromes (PHN, CRPS, etc) These are local anesthetic injections that may be repeated many times in a series over a short period of time The mechanism of action is to disrupt the pain transmission and allow the nerve impulse to revert to it’s usual state

MEDIAL BRANCH NERVE BLOCK AND RADIO FREQUENCY LESIONING It is a synovial joint between the superior articular process and inferior articular process of two vertebra The medial branch nerve derives from the corresponding spinal nerve transmitting sensory information from each joint Disease of the facet joints is seen with aging In simplest form, these changes are arthritic and degenerative It produces axial pain, usually with activity

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MEDIAL BRANCH NERVE BLOCK AND RADIO FREQUENCY LESIONING Facet joint injections used to be the treatment of choice for this condition With new technologies and advanced imaging joint injections are rarely performed

MEDIAL BRANCH NERVE BLOCK AND RADIO FREQUENCY LESIONING Prior to RF, the patient should undergo one or two diagnostic MBNBs with local anesthetic They should have significant relief of their symptoms( 50% or greater), however, it will not be long lasting Subsequent diagnostic blocks may be necessary as there is a contribution from the levels above and below

MEDIAL BRANCH NERVE BLOCK AND RADIO FREQUENCY LESIONING Radio frequency lesioning or neurotomy is performed using a specialized machine to produce a radio wave to “burn” a specific nerve blocking the transmission of the painful impulse The lesion should provide relief for 6-9 months There is regeneration of the neural pathway which allows the pain to return This procedure can be repeated

MEDIAL BRANCH NERVE BLOCK AND RADIO FREQUENCY LESIONING Symptoms or conditions that may have a facet component Headaches Neck, mid or lower back pain Post fusion neck or back pain

SYMPATHETIC BLOCKS These blocks are performed when pain is neuropathic with a sympathetic component The blocks interrupt the nerve transmission in a large area of the body They are performed at the ganglion

SYMPATHETIC BLOCKS Stellate Ganglion Block Performed by injecting 10 cc of local anesthetic in proximity to the stellate ganglion Used to treat upper extremity pathology CRPS, PHN

SYMPATHETIC BLOCKS Celiac Plexus Block Performed by injecting local anesthetic in proximity of the celiac plexus Used to treat pathology of the abdomen Should always be performed with imaging (CT Scan or fluoroscopy)

SYMPATHETIC BLOCKS Lumbar Paravertebral Sympathetic Block Performed to treat neuropathic pain of the lower extremity

Post Operative Pain Nerve blocks can be performed to manage post operative pain Best used for extremity procedures Shoulder - Interscalene Hand - Supraclavicular/Axillary Ankle - Sciatic (Popliteal) Single shot~12-18 hours Peripheral catheters may be used for several days with Ambit/On Q pump

Post Operative Pain Single shot nerve blocks (18 Hrs) Peripheral nerve catheters (3 Days) Epidural

Post Operative Pain Epidural Thoracic - Thoracotomy Abdominal - Exploratory laparotomy

NEUROAUGMENTATION Spinal Cord Stimulation (SCS) and Peripheral Nerve Stimulation (PNS) are technologies that are available for patients that have not responded to the previous modalities They require the implantation of lead(s) and a battery generator SCS lead(s) are placed into the epidural space PNS lead(s) are placed in the subcutaneous tissue

NEUROAUGMENTATION SCS works by having a low voltage electrical stimulation to block the pain transmission via the dorsal column tracts of the spinal cord It can be utilized for cervical, thoracic or lumbar symptoms More effective for extremity than truncal symptoms

NEUROAUGMENTATION PNS is utilized to provide pain relief over a peripheral nerve distribution The lead(s) are place along the course of peripheral nerves May be effective for occipital headaches, inguinal neuralgia, intercostal neuralgia

INTRATHECAL THERAPY An implanted infusion delivery system that delivers a precise amount of medication into the spinal fluid via an infusion pump and catheter Baclofen (spasticity) and Morphine (pain) are the two most common medications delivered through this modality

INTRATHECAL THERAPY Who is a candidate for this therapy? Failed all previous modalities Medication requirements have produced intolerable side effects Patients who cannot achieve adequate pain control even with high doses of opioids

CONCLUSION Interventional pain management should be considered with any pain condition Pain is most effectively treated with a multi-disciplinary approach We should utilize all resources that are available

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