Spinal Procedures

Overview and Description

Types of spine procedures

Epidural steroid injections (ESI)

• Places a corticosteroid and an anesthetic into the epidural space by either an interlaminar, transforaminal, or caudal approach.
• Addresses radicular pain secondary to intervertebral disc herniation or spondylotic central, lateral recess, or foraminal stenosis.¹
• Can provide pain relief by:
  • Interrupting the inflammatory cascade²
  • Blocking nociceptive C-fiber transmission²
  • Increasing microcirculation around ischemic areas¹
  • Modulating pain transmission in the dorsal horn¹
• As a treatment for radicular pain, ESIs are an effective but not long-lasting treatment according to The American Society of Pain and Neuroscience (ASPN) and The American Society of Interventional Pain Physicians (ASIPP).^3,4

Zygapophyseal (facet) joint injections/medial branch blocks (MBB) and sacroiliac joint injections

• Intra-articular facet joint injections with placement of corticosteroid and an anesthetic into the facet joint have been shown to be ineffective when used either therapeutically or diagnostically prior to radiofrequency ablation (RFA).³
• MBBs involve the use of a local anesthetic to block the medial branch (of the primary dorsal ramus of the spinal nerve) that provides nociceptive output from the facet joint.⁵
• MBBs are effective in diagnosing facet mediated pain prior to RFA.⁵
• Sacroiliac joint injections involve intra-articular placement of corticosteroid and an anesthetic into the joint for diagnostic or therapeutic value.
  • Most studies have shown at least moderate efficacy when used either therapeutically or diagnostically prior to RFA.^3,4

 Radiofrequency Ablation (RFA) / Thermal Radiofrequency Neurotomy (TRN)

• RFA/TRN uses the application of radiofrequency current to create heat to lesion the afferent nerve supply of the facet and sacroiliac joints.⁶
• The decision to perform an RFA follows a successful diagnostic MBB. In general, greater improvement of pain following MBBs correlates with better outcomes after RFA.⁶
• Performed to provide pain relief by denervation of facet or sacroiliac joints for an extended period of time.
• Nerve regeneration is expected to occur over 9 to 12 months.⁶
• RFA is an effective treatment for low back pain, especially when prior diagnostic blocks have resulted in a high level of pain relief.^3,4

Discography

• Placement of contrast dye within the intervertebral disc nucleus pulposus under fluoroscopy followed by computed tomography (CT) imaging of the spine.
• Performed to identify the disc as the source of a patient’s axial pain.
• Validity of discography remains controversial.⁷
• There is concern that discography may cause accelerated disc degeneration and herniation.⁷
• Infrequently utilized in contemporary practice, however, is useful for research purposes.⁷

Thermal annuloplasty

• Application of heat along the annulus to denervate it and/or reconfigure the collagen structure of the disc to stabilize annular tears and relieve pain.⁸
• Effectiveness of these interventions based on recent randomized controlled trials (RCT) is controversial.⁸
• Heat-based procedures include the following:
  • Biacuplasty involves the utilization of bipolar and monopolar RFA electrodes to create lesions in the posterior and posterolateral annulus which coagulates nociceptors.⁸
  • Coblation nucleoplasty involves the use of a bipolar radiofrequency current to decrease the volume of the disc tissue leading to decompression.⁹
  • Intradiscal electrothermal therapy:
    • Involves placement of an electrode or catheter into the disc annulus to apply electrothermal energy which denervates the annulus.⁸
    • Has received noncoverage status from the Center for Medicare and Medicaid Services because of the lack of supporting evidence.⁹

Percutaneous disc decompression (PDD)

• Aims to remove a portion of the disc nucleus material in order to reduce intradiscal pressure, limit release of inflammatory mediators and decompress the spinal cord and/or nerve root.¹⁰
• Addresses radicular pain secondary to intervertebral disc herniation.¹⁰
• PDD techniques include percutaneous laser disc decompression (PLDD), coblation nucleoplasty, and automated lumbar discectomy (APLD).¹⁰
• Literature has presented successful outcomes for these procedures with limited adverse events, but overall efficacy remains controversial.^3,4,10

Vertebroplasty and kyphoplasty

• Vertebroplasty consists of injecting a polymethyl methacrylate (PMMA) cement into the vertebral body.
• Kyphoplasty inflates a balloon within the vertebral body prior to the application of PMMA.¹¹
• Mechanism of action is a combination of thermal necrosis and chemotoxicity of the intraosseous pain receptors.¹¹
• Clinical outcomes between kyphoplasty and vertebroplasty are similar, however kyphoplasty increases vertebral body height and reduces cement leakage while vertebroplasty is a quicker procedure and more cost efficient.¹²

Spinal cord stimulation (SCS) of the dorsal columns

• Involves implantation of electrodes in the epidural space which are theorized to block transmission of pain by way of Melzack and Wall’s gait control theory.¹³ However, exact mechanism of action has not been established.¹³
• Indicated for intractable chronic pain refractory to medications, physical therapy and other procedural interventions.
• Conventional paresthesia based low frequency (50 Hz) systems are utilized to address radicular pain symptoms.¹³
• Newer systems utilize either dorsal root ganglion SCS or paresthesia-free SCS (burst SCS or high frequency SCS). ¹³
• Patients undergo an initial SCS trial with an external power source and if successful, will receive an implanted subcutaneous pulse generator.¹³
• There is a high level of evidence supporting the efficacy of SCS for patients with failed back surgery syndrome and a moderate level of evidence for other types of patients including those with non-surgical back pain and/or predominant lumbar stenosis.^3,4,13

Intrathecal drug delivery system (IDDS)

• Delivers medication intrathecally, directly at the dorsal horn to maximize effectiveness and minimize the dose.¹⁴
• The only two medications which are approved by the US Food and Drug Administration (FDA) are Morphine and Ziconotide.¹²
• This treatment reduces systemic side effects and eliminates the risk of opioid abuse and diversion.¹⁴
• Often a trial is completed in which medication is administered via an external pump or bolus injection to the intrathecal or epidural space. For permanent treatment, a catheter is implanted intrathecally and a pump containing medication is stored in the abdominal wall or buttocks area.¹⁴
• While there is substantial research demonstrating the efficacy and safety of IDDS, there are a limited number of RCTs examining its use in chronic non-cancer pain and chronic low back pain specifically.^3,4,14

Percutaneous image-guided lumbar decompression

• Minimally invasive lumbar decompression (MILD^®)
  • A treatment option for patients with lumbar spinal stenosis with neurogenic claudication and verified ligamentum flavum hypertrophy.¹⁵
  • A percutaneous intervention of debulking hypertrophied ligamentum flavum using image-guided dissection and epidurogram for visualization of each debulking step.¹⁵
  • Pursued after failure of more conservative treatment methods.¹⁵
  • Demonstrated to be an efficacious procedure, with good outcomes and safety-profile.^3,15
• Interspinous spacer
  • A metal implant that is delivered percutaneously to relieve back pain resulting from lumbar spinal stenosis.
  • The device is implanted at one or two adjacent lumbar levels between spinous processes. This produces flexion of the lumbar spine at that level to tighten the hypertrophic ligamentum flavum. This limits the ligamentum from protruding into the spinal canal and as a result maintains a larger canal diameter.^3,15
  • The two FDA approved devices are Coflex^® and Vertiflex^®.^3,15
  • Numerous studies have shown this procedure to be a safe and effective treatment for spinal stenosis.^3,4

Relevance to Clinical Practice

Risks associated with invasive procedures

Medication-related complications

• Local anesthetic medications
  • Anesthetic allergic reactions are rare but can occur either because of the anesthetic or its preservative, methylparaben.¹⁶
  • Central nervous system toxicity can occur because of excessive anesthetic use.
    • Signs of toxicity include disorientation, light-headedness, nystagmus, tinnitus, and muscle twitching in the face or extremities.¹⁶
    • Cardiovascular effects include chest pain, shortness of breath, palpitations and hypotension.¹⁶
• Corticosteroid preparation-related side effects
  • Intrathecal injections containing methylprednisolone can cause arachnoiditis, due to a reaction from the preservative; polyethylene glycol.¹⁶
  • Epidural administration can cause fluid retention, steroid-induced myopathy, irregular menses, epidural lipomatosis with prolonged use, digestive irritation, and elevations in serum glucose.¹⁶
  • Less common side effects include elevated body temperature, euphoria, depression, mood lability, local fat atrophy, skin pigmentation changes, and pain flare.¹⁶
  • Rare complications include the following: weight gain, deep vein thrombosis, hypertension, and Cushing syndrome.¹⁶

Fluoroscopic guidance-related issues

• Contrast media-related effects
  • Spine procedures are typically performed under fluoroscopy to confirm proper needle positioning.
  • Injection of contrast under real-time fluoroscopy or with digital subtraction angiography can assess for vascular injection.¹
  • Anaphylactic reactions to contrast have been reported to have an incidence of 0.04%.¹⁷
  • Patients with contrast sensitivity should be considered for premedication depending on the severity of the reaction. Pharmacological therapy may include a histamine H1 blocker (e.g., ranitidine), histamine H2 blocker (e.g., diphenhydramine), or corticosteroid (e.g., prednisone).
• Radiation exposure
  • Methods to decrease exposure include minimizing duration of exposure, reducing proximity to radiation source, and using personal protective equipment including lead shields.

Infection-related risks

• Epidural abscesses have been reported in the cervical, thoracic, and lumbar spine.¹⁷
  • Most common bacteria identified was Staphylococcus aureus.
  • Typical presentation includes the following: fever, spinal pain, radicular pain, and/or progression of neurologic deficits.
  • Symptoms occur from 3 days to 3 weeks following the injection.
• Meningitis can occur when the dura is punctured during epidural procedures.¹⁷
  • Types of meningitis reported include bacterial, fungal, and aseptic.
  • Patients have presented with headache, fever, nausea, leg pain, and convulsions.
• Osteomyelitis and discitis have been reported in cervical, thoracic, and lumbar discography.¹⁷
  • Typical signs include the following: fever, malaise, lethargy, pain, and neurologic changes.
  • These can present one to four weeks after the injection.
• Infectious risks are minimized by use of strict sterile technique. Early detection is necessary to minimize morbidity and mortality.¹⁷

Bleeding-related complications

• There is an increased risk of bleeding and epidural hematoma formation in patients with clotting-related disorders including hemophilia, von Willebrand disease, thrombocytopenia, and idiopathic thrombocytopenic purpura, in addition to patients with liver and renal disease.
• Baseline complete blood count should be obtained prior to spinal injections to identify any pre-existing hematological conditions including anemia or thrombocytopenia.
• Epidural hematomas typically occur as a result of impaired coagulation.
  • Physicians must have a low threshold for identifying the signs and symptoms of an epidural hematoma as this is a medical emergency.
  • Symptoms include unexpected duration or spread of sensory and/or motor deficits, unexplained severe spinal or radicular pain, and bowel or bladder dysfunction.

Table 1. Classification of interventional spine procedures based on risk of serious bleeding¹⁸

Table 2. Management of anticoagulants and antiplatelet medications prior to following interventional spine procedures¹⁸

Neurologic complications of epidural injections

• Can occur with nerve root injury or spinal cord injury
• Transforaminal epidural steroid injection
  • May have rare catastrophic complications when performed in the cervical spine region
  • Complications are associated with embolic events because of inadvertent intra-arterial injection. There is a greater association with particulate steroids than non-particulate steroids.
  • Complications include brain infarction, spinal cord infarction, cortical blindness, high spinal anesthesia, and seizures.^1,17
• Interlaminar epidural steroid injection
  • Complications include dural puncture with cord trauma and post-dural puncture headache
  • Post-dural puncture headache (PDPH)
    • Risk is reduced with the use of a smaller gauge needle.
    • Symptoms include nausea, vomiting, hearing loss, tinnitus, vertigo, dizziness, paresthesia of the scalp, and limb pain.
    • The incidence of PDPH is higher in older population (>51 years) compared to younger population (<50 years)¹⁹
    • Spontaneous recovery is typical within 6 weeks for most patients.
    • Application of a blood patch is the most definitive treatment for spinal headaches.¹⁹

Respiratory risks and complications

• Respiratory depression can occur from excessive sedation.
• Trauma to the spinal cord from needle injury or pneumothorax can occur in cervical and thoracic level procedures.
• Recurrent laryngeal nerve injury can lead to transient-reduced airway protection and voice hoarseness in cervical-level injections.¹⁷

Urologic risks and complications

• The most common complication is urinary retention, which can occur from injection of local anesthetic into the spine.
• Urologic compromise can occur secondary to formation of an epidural abscess or hematoma, leading to cauda equina and/or cord compression.¹⁷

Spinal Cord Stimulator Complications

• Incidence of complications are reported to be as high as 40%.²⁰
• Complications are divided into hardware-related failure, biological-related complications, or programming-related complications.
• Hardware related complications
  • Most common type of complication.²⁰
  • Lead-related complications including lead migration, lead fracture, extension-related complications, or connection problems.
  • Lead migration is the most common complication of spinal nerve stimulation.²⁰
  • Pulse generator complications include battery failure and recharging difficulties.
• Biological-related complications
  • Most frequently: infection, hematoma or seroma development over the implant site, pain over implant site, or wound breakdown.²⁰
  • Less frequently, neurologic complications occur including dural puncture headache, spinal cord injury, and paralysis.²⁰
• Programming complications
  • Includes painful or unpleasant paresthesias.
  • These may be rectified with programming alterations of the spinal cord stimulator. However, with total therapy failure, the device may be removed.²⁰

Given the potential risks, care must be taken to identify appropriate candidates. Clinical evaluation includes the following

Comprehensive history

• Necessary in order to evaluate patients for the treatment of spine pain.
• Includes pain onset, location/radiation, character, intensity, timing/duration, associated symptoms and aggravating activity/movements.
• History of a directional bias can help further elucidate the probable pain generators.
  • Pain with flexion can be suggestive of discogenic or vertebral body pain as a pain source.
  • Pain with extension can be suggestive of facet joint involvement; or central, lateral recess, or foraminal nerve impingement.
• Review red flags that may signal the presence of serious systemic disease, such as incontinence, saddle anesthesia, severe/rapidly progressive neurologic deficit, and constitutional signs and symptoms including fever, chills, and night sweats.²¹
• Caution should be taken to identify medications which could impact the safety of the procedure such as anti-platelet/anticoagulant medications. Obtain necessary preprocedural clearance to discontinue these medications as indicated.
• Thorough review of allergies
• Thorough review of radiologic studies and foresight to obtain necessary additional studies to optimize treatment safety and efficacy.

Physical examination of the spine

• Includes inspection of posture and alignment, palpation for concordant pain provocation, range of motion, and provocative maneuvers/special tests.
• Joints in close proximity to the spine must also be evaluated.
• Thorough neurologic exam to assess for upper and lower motor neuron dysfunction
  • Manual muscle strength testing
  • Sensory examination
  • Coordination
  • Deep tendon reflexes
  • Gait

Laboratory tests

• Performed to exclude the presence of an occult malignancy, indolent infection, or inflammatory disease.
• The following laboratory tests are commonly performed¹⁹
  • Complete blood cell count
  • Basic metabolic panel
  • International normalized ratio (INR)

Imaging of the spine¹

• Plain radiographs
  • Often used as the first-line imaging study in spinal pain.
  • Limited value because of the inability to see soft tissue structures, such as spinal discs, nerves, muscles, and ligaments. May be useful to assess for segmental stability, degenerative changes and surgical hardware failure.
• Magnetic resonance imaging (MRI)
  • Most commonly utilized modality for the investigation of spinal radiculopathy.
  • High sensitivity and low specificity.
  • Lacks the radiation exposure of CT and bone scintigraphy.
• CT
  • Gives superior visualization of cortical bone when compared with MRI.
  • Of value when MRI is contraindicated in the presence of
    • Pacemakers, implantable cardioverter-defibrillators (ICD), internal pacing wires, or vascular clips
    • Swan-Ganz catheter
    • Cochlear implants
    • Spinal cord stimulators
    • Metallic artifacts
    • Pregnancy
• Bone scintigraphy (single-photon emission computed tomography and triple-phase bone scan)
  • Bone scintigraphy can identify areas of altered metabolic activity.
  • Can identify areas of increased osteoblastic activity and blood flow.
  • Most useful to identify stress fractures, joint inflammation, and metastatic disease.

Formal procedure guidelines have been published by the International Spine Intervention Society and the American Society of Interventional Pain Physicians.¹

Cutting Edge/ Unique Concepts/ Emerging Issues

• With the widespread burden of the opioid epidemic, the paradigm of pain management has shifted from conservative care to more minimally invasive and corrective interventions.
• Ultrasound guidance has begun to play an emerging role in performing spine procedures, as it provides a radiation-free means for visualization of joints, tendons, muscles, ligaments, nerves, and blood vessels. In a randomized study, ultrasound was shown to be as efficacious as fluoroscopy when performing cervical transforaminal ESI.²³
• As more long-term research outcomes are produced, recent minimally invasive solutions such as, percutaneous interspinous spacer implantation and MILD, are revealed to be non-inferior to ESI for lumbar spinal stenosis, especially in patients who are not amenable or good surgical candidates.
  • Percutaneous interspinous spacer implantation has revealed pain improvement in the visual analog scale (VAS) and Oswestry Disability Index (ODI) at the 5-year mark, implying utility and long-term market stability.¹⁵
  • MILD was shown to have the lowest re-operation rate with a lower risk of infection when compared to other implants and open surgery.¹⁵
• Within recent years, interest in intraosseous basivertebral nerve (BVN) ablation has risen as a relatively new intervention. Outcome measures have been shown to significantly improve pain relief with improvements in the VAS comparable to conservative treatments.¹⁵
• Interventional pain innovation moving forward is focused on neuromodulation and corrective solutions of spine and peripheral joint pathology.¹⁵

Gaps in Knowledge/ Evidence Base

The range of spine procedures and their application has grown significantly over the past 20 years because of:

• Increasing demand by patients for these procedures.
• Increasing number of physicians trained to perform them.

New innovations and interventions have shown some efficacy in select patients, but for most of these procedures, long-term benefit still remains to be established.¹⁵

The continued need for high-quality studies comparing efficacy and validating long-term benefit has been limited by the following:

• Limited research training and funding among interventional pain institutions and physicians.¹⁵
• Lack of consensus regarding study methodology.
• The difficult nature of subject recruitment for placebo-controlled pain studies.¹⁵

References

1. Krämer J, Theodoridis T. Spinal injection techniques. 2nd ed. Thieme Medical Publishers Incorporated; 2019.
2. Coutinho AE, Chapman KE. The anti-inflammatory and immunosuppressive effects of glucocorticoids, recent developments and mechanistic insights. Mol Cell Endocrinol. 2011;335(1):2-13. doi:10.1016/j.mce.2010.04.005
3. Sayed D, Grider J, Strand N, et al. The American Society of Pain and Neuroscience (ASPN) Evidence-Based Clinical Guideline of Interventional Treatments for Low Back Pain. J Pain Res. 2022;15:3729-3832. doi.org/10.2147/JPR.S386879
4. Manchikanti L, Abdi S, Atluri S, et al. An update of comprehensive evidence-based guidelines for interventional techniques in chronic spinal pain. Part II: guidance and recommendations. Pain Physician. 2013;16(2 Suppl):S49-S283.
5. Du R, Xu G, Bai X, Li Z. Facet joint syndrome: pathophysiology, diagnosis, and treatment. J Pain Res. 2022;15:3689-3710. doi:10.2147/JPR.S389602
6. Gill B, Cheney C, Clements N, Przybsyz AG, McCormick ZL, Conger A. Radiofrequency ablation for zygapophyseal joint pain. Phys Med Rehabil Clin N Am. 2022;33(2):233-249. doi:10.1016/j.pmr.2022.01.001
7. Manchikanti L, Soin A, Benyamin RM, et al. An update of the systematic appraisal of the accuracy and utility of discography in chronic spinal pain. Pain Physician. 2018;21(2):91-110.
8. Helm Ii S, Simopoulos TT, Stojanovic M, Abdi S, El Terany MA. Effectiveness of thermal annular procedures in treating discogenic low back pain. Pain Physician. 2017;20(6):447-470.
9. Zhu H, Zhou XZ, Cheng MH, Shen YX, Dong QR. The efficacy of coblation nucleoplasty for protrusion of lumbar intervertebral disc at a two-year follow-up. Int Orthop. 2011;35(11):1677-1682. doi:10.1007/s00264-010-1196-0
10. Gelalis I, Gkiatas I, Spiliotis A, et al. Current concepts in intradiscal percutaneous minimally invasive procedures for chronic low back pain. Asian J Neurosurg. 2019;14(3):657-669. doi:10.4103/ajns.AJNS_119_17
11. Lavelle W, Carl A, Lavelle ED, Khaleel MA. Vertebroplasty and kyphoplasty. Anesthesiology Clinics. 2007;25(4):913-928. doi:10.1016/j.anclin.2007.07.011
12. Daher M, Kreichati G, Kharrat K, Sebaaly A. Vertebroplasty versus kyphoplasty in the treatment of osteoporotic vertebral compression fractures: a meta-analysis. World Neurosurg. 2023 Mar;171:65-71. doi: 10.1016/j.wneu.2022.11.123. Epub 2022 Nov 28. PMID: 36455843.
13. Verrills P, Sinclair C, Barnard A. A review of spinal cord stimulation systems for chronic pain. J Pain Res. 2016;9:481-492. Published 2016 Jul 1. doi:10.2147/JPR.S108884
14. Van Zundert J, Rauck R. Intrathecal drug delivery in the management of chronic pain. Best Pract Res Clin Anaesthesiol. 2023. doi:10.1016/j.bpa.2023.02.003
15. Eshraghi Y, Shah JD, Guirguis M. Novel technologies in interventional pain management. Phys Med Rehabil Clin N Am. 2022;33(2):533-552. doi:10.1016/j.pmr.2022.01.006
16. Liu H, Brown M, Sun L, et al. Complications and liability related to regional and neuraxial anesthesia. Best Pract Res Clin Anaesthesiol. 2019;33(4):487-497. doi:10.1016/j.bpa.2019.07.007
17. Botwin K, Brown L, Sakalkale D, et al. Side effects and complications of injection procedures: anticipation and management. In: Slipman C, Derby R, Simeone F, et al, eds. Interventional Spine an Algorithmic Approach. 1st ed. Philadelphia, PA: Saunders Elsevier; 2008:213-227.
18. Narouze S, Benzon HT, Provenzano D, et al. Interventional Spine and Pain Procedures in Patients on Antiplatelet and Anticoagulant Medications (Second Edition): Guidelines From the American Society of Regional Anesthesia and Pain Medicine, the European Society of Regional Anaesthesia and Pain Therapy, the American Academy of Pain Medicine, the International Neuromodulation Society, the North American Neuromodulation Society, and the World Institute of Pain. Reg Anesth Pain Med. 2018;43(3):225-262. doi:10.1097/AAP.0000000000000700
19. Wadud, Roheena & Laiq, Nasreen & Akhtar Qureshi, Fayyaz & Said Jan, Akbar. (2006). The frequency of postdural puncture headache in different age groups. Journal of the College of Physicians and Surgeons–Pakistan : JCPSP. 16. 389-92.
20. Eldabe S, Buchser E, Duarte RV. Complications of Spinal Cord Stimulation and Peripheral Nerve Stimulation Techniques: A Review of the Literature. Pain Med. 2016;17(2):325-336. doi:10.1093/pm/pnv025
21. Alexander E. History, physical examination, and differential diagnosis of neck pain. Phys Med Rehabil Clin N Am. 2011;22:383-393.
22. Dreyer S, Boden S. Laboratory evaluation in neck pain. Phys Med Rehabil Clin N Am. 2003;14:589-604.
23. Jee H, Lee JH, Kim J, et al. Ultrasound-guided selective nerve root block versus fluoroscopy-guided transforaminal block for the treatment of radicular pain in the lower cervical spine: a randomized, blinded, controlled study. Skeletal Radiol. 2013;42:69-78.

Original Version of the Topic

Ali Shakir, MD. Spinal procedures. 9/20/2013

Previous Revision(s) of the Topic

Jeffrey Oken, MD, Victor Foorsov, MD. Spinal procedures. 9/21/2018

Author Disclosure

Alex Vertes, MD
Nothing to Disclose

Anam Purewal, MD
Nothing to Disclose

Jason Do, DO
Nothing to Disclose

Sanjeev Agarwal, MD
Nothing to Disclose