Insufficient research on interventional pain therapies for managing low back pain during pregnancy

Abstract

In nonpregnant patients, fluoroscopy-guided epidural steroid injections (ESIs) have strong evidence (Level 1) supporting their use for managing low back pain (LBP) caused by disc herniation (DH) [[1]]. Fluoroscopy-guided interventional procedures cannot be used in pregnant patients due to the risk of exposing the fetus to ionizing radiation. Non-image-guided ESI using the loss of resistance technique, combined with ultrasound for localization, is a safe option for pregnant patients. However, the use and effect of interventional procedures like ESI for radicular low back pain in pregnant patients have not been studied. A systematic review of current standards in the treatment of pain from DH (with no features of cauda equina) during pregnancy does not describe the use of ESI and recommends conservative management with physiotherapy [[2]]. There is only one published case report regarding the successful management of radicular pain in pregnancy using caudal ESI [[3]]. Despite this, pain physicians often receive referrals for ESIs to manage pregnant patients with LBP.

In our practice, we had 2 cases where interventional procedures were performed on pregnant patients with LBP. The first patient was 32 years old, G1P0 at 9 weeks of pregnancy, and presented with LBP radiating to the right thigh and calves for the last 4 months. Her MRI showed right L4-L5 disc extrusion and impingement of the right L5 nerve root. Non-image-guided ESI performed during pregnancy at L5-S1 provided no relief, but a fluoroscopy-guided ESI after delivery provided 50% pain relief for a month. She eventually underwent surgery and reported complete pain resolution. The second patient was 35 years old at 18 weeks of pregnancy with left-sided LBP for 6 months. Her MRI showed DH at L4-L5 with L5 nerve impingement on the left side. Non-image-guided ESI at L5-S1 at that time provided 60% pain relief which lasted 8 weeks, but her pain returned in the third trimester. She received a fluoroscopy-guided ESI post-partum, which provided complete, immediate, and sustained pain relief.

These cases demonstrate varying outcomes of interventional pain procedures if performed during pregnancy. Due to the limited research and inconsistent results, caution should be exercised when offering interventional procedures to pregnant patients and as noted by Santos et al. physicians should prioritize the prevention of low back pain through physiotherapy and exercise [[4]].

Ethical approval

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Funding

No funding was required for this project.

Conflict of interest

The authors declare that they have no conflict of interest.