Back Injections for Sciatica in Patients on Anticoagulants
Neuraxial procedures (including therapeutic spinal injections for sciatica) are contraindicated in patients on therapeutic anticoagulation due to the risk of spinal or epidural hematoma, which can cause permanent paralysis. 1, 2
Understanding the Risk Classification
The critical issue is that therapeutic spinal injections fall into the "very high hemorrhagic risk" category because bleeding in the neuraxial space cannot be compressed and can result in catastrophic neurological consequences. 1
Specific risks include:
- Spinal or epidural hematoma formation that can cause long-term or permanent paralysis 2, 3, 4
- Irreversible neurological damage if hematoma is not evacuated within 8-12 hours 5
- Risk of reoperation, transfusion, and nerve damage by compression 1
Management Algorithm for Patients Requiring Spinal Injections
If the Procedure Can Be Delayed (Non-Emergency)
For patients on warfarin:
- Hold warfarin until INR ≤1.4 before performing the procedure 6, 5
- Verify INR within 24 hours before the injection 6
For patients on direct oral anticoagulants (DOACs like apixaban, rivaroxaban):
- Stop medication with last dose at D-5 (5 days before procedure) OR verify plasma concentration <30 ng/mL 2
- For rivaroxaban specifically: stop 18 hours before procedure for prophylactic dosing 5
- For dabigatran: stop 48-96 hours before procedure depending on renal function 5
For patients on low molecular weight heparin (LMWH):
- Hold for 12 hours before procedure for prophylactic dosing 6
- Hold for 24 hours before procedure for therapeutic dosing 6
If the Procedure Cannot Be Delayed (Emergency)
For patients on dabigatran:
- Administer idarucizumab (specific reversal agent) before the procedure to immediately restore normal coagulation 1
- If idarucizumab is unavailable, prothrombin complex concentrates (PCCs) cannot be recommended as they do not adequately neutralize dabigatran 1
For other anticoagulants:
- Consult hematology for reversal strategies 6
- Consider alternative diagnostic or therapeutic approaches rather than proceeding with neuraxial injection 6
Critical Safety Considerations
The procedure must be performed by an experienced operator using:
- Fine needle technique 1
- Ultrasound or fluoroscopic guidance when available 1
- Single puncture technique to minimize trauma 1
Absolute contraindications that must be ruled out:
- Active systemic or spinal infection 2
- Uncorrectable bleeding diathesis 2
- Severe thrombocytopenia (platelet count <50,000/mcL) 2
- Recent central nervous system bleeding 2
- Active major bleeding requiring >2 units blood transfusion in 24 hours 2
Post-Procedure Monitoring
All patients must be monitored for signs of spinal hematoma:
- Test for straight-leg raising at 4 hours after procedure 5
- Document motor function using Bromage scale 5
- Immediately assess if patient cannot perform straight-leg raise at 4 hours 5
Emergency warning signs requiring immediate evaluation:
- Back pain, tingling, numbness, or muscle weakness (especially in legs and feet) 2, 3, 4
- Loss of bowel or bladder control 4
- Progressive neurological deficits 5
Important Clinical Caveats
Peripheral nerve blocks for sciatica (such as sciatic nerve block in the popliteal fossa) represent a lower-risk alternative:
- These superficial blocks can be performed under anticoagulation if the benefit/risk ratio is favorable, as bleeding is compressible 1
- However, deep blocks (parasacral sciatic block, posterior lumbar plexus block) remain contraindicated under anticoagulation 1
The risk of stopping anticoagulation must be weighed against the benefit of the injection:
- Patients with atrial fibrillation face increased stroke risk when anticoagulation is interrupted 3, 4
- Patients may require bridging anticoagulation during the interruption period 6
- The procedure should only proceed if the therapeutic benefit clearly outweighs the thrombotic risk of stopping anticoagulation 1
Do not confuse this with joint injections for arthritis: