Medial branch block injections are safe and well-tolerated by most patients.1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051
As with any injection procedure, there are potential risks, but the side effects are typically minor and transient, and serious complications are rare.1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051,2Le DT, Alem N. Facet Joint Injection. [Updated 2023 Jun 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK572125/
In This Article:
- Medial Branch Nerve Blocks
- Medial Branch Injection Procedure
- Risks and Complications of Medial Branch Blocks
- Medial Branch Block Video
Potential Side Effects of Medial Branch Blocks
Medial branch block injections typically cause mild and temporary localized side effects, such as1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051:
- Pain and soreness
- Numbness
- Weakness in the arms and/or legs
- Bleeding and/or bruising
- Vasovagal reactions (slow heart rate, sweating, and dizziness)
If corticosteroids are used, temporary flushing, headache, increased injection site pain (also called “steroid flare"), and agitation may occur in some cases.1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051,3Alsop RJ, Khondker A, Hub JS, Rheinstädter MC. The Lipid Bilayer Provides a Site for Cortisone Crystallization at High Cortisone Concentrations. Sci Rep. 2016;6:22425. Published 2016 Mar 3. doi:10.1038/srep22425
The recommended treatments for these temporary effects include the application of ice and/or over-the-counter pain medications (eg, Tylenol and Advil).
See Medications for Back Pain and Neck Pain
Avoiding the use of pain medication for the first 4 to 6 hours after the injection is recommended to ensure an accurate assessment of the procedure's effectiveness.
Potential Risks and Adverse Events of Medial Branch Blocks
The complications associated with medial branch block injection procedures are primarily related to incorrect needle placement and/or sensitivity to the medications used, and include1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051,2Le DT, Alem N. Facet Joint Injection. [Updated 2023 Jun 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK572125/:
- Excessive bleeding and bruising
- Infection
- Allergic reaction to medication or contrast dye
- Worsening of pain
- Nerve damage, including permanent weakness of the arms and/or legs
- Spinal cord damage or paralysis
When imaging is used, the risks of nerve injury and inadvertent injection of medication into nearby blood vessels, nerves, or tissue are low.1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051,2Le DT, Alem N. Facet Joint Injection. [Updated 2023 Jun 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK572125/
Potential risks of corticosteroid use in medial branch block injections
Corticosteroids used in therapeutic blocks carry a risk of significant complications due to the potential for absorption into the bloodstream, including4Stout A, Friedly J, Standaert CJ. Systemic Absorption and Side Effects of Locally Injected Glucocorticoids. PM R. 2019;11(4):409-419. doi:10.1002/pmrj.12042:
- Osteonecrosis
- Decreased bone mineral density
- Reproductive hormone imbalance
- Psychiatric changes (eg, agitation, irritability, insomnia)
- Increased blood sugar (hyperglycemia)
- High blood pressure (hypertension)
- Fluid retention
- Adrenal suppression
Additionally, chronic exposure to corticosteroids from repeated therapeutic blocks and/or the presence of underlying medical conditions (eg, diabetes, osteoporosis, and heart disease) increases the risk of serious adverse events.3Alsop RJ, Khondker A, Hub JS, Rheinstädter MC. The Lipid Bilayer Provides a Site for Cortisone Crystallization at High Cortisone Concentrations. Sci Rep. 2016;6:22425. Published 2016 Mar 3. doi:10.1038/srep22425
Long-term risks of medial branch block injections
In some cases, nerve injury and/or untreated infections may cause permanent damage, but these complications are rare.1Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051,2Le DT, Alem N. Facet Joint Injection. [Updated 2023 Jun 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK572125/
It is advisable to discuss the risks, benefits, and alternative treatments with your doctor before proceeding with medial branch block injections.
- 1 Carr CM, Plastaras CT, Pingree MJ, et al. Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study. Pain Medicine. 2016;17(12):2155-2161. doi: 10.1093/pm/pnw051
- 2 Le DT, Alem N. Facet Joint Injection. [Updated 2023 Jun 20]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK572125/
- 3 Alsop RJ, Khondker A, Hub JS, Rheinstädter MC. The Lipid Bilayer Provides a Site for Cortisone Crystallization at High Cortisone Concentrations. Sci Rep. 2016;6:22425. Published 2016 Mar 3. doi:10.1038/srep22425
- 4 Stout A, Friedly J, Standaert CJ. Systemic Absorption and Side Effects of Locally Injected Glucocorticoids. PM R. 2019;11(4):409-419. doi:10.1002/pmrj.12042