Adding Particulate or Non-Particulate Steroids to the Local Anesthetics When Performing Parasagittal Interlaminar Epidural Injections.

We read with great interest a recent study by Ghai et al (1) wherein they followed 56 out of 69 randomized patients for 12 months following parasagittal interlaminar (PIL) injection with local anesthetics (LA) alone or LA with steroid (LS). We agree with author’s choice of technique to achieve adequate and consistent ventral epidural spread of injectate. Parasagittal interlaminar epidural steroid injections are underrepresented in the literature and frequently are not differentiated from midline interlaminar epidural steroid injections, by authors performing analyses of efficacy. We were successful at presenting the advantages of PIL-ESI with regards to ventral spread of contrast (2), clear superiority to midline interlaminar (MIL-ESI) (3), and non-inferiority to transforaminal epidural steroid injections (TF-ESI)(2). In 2008, we used an independent blinded radiologist not affiliated with primary study institution to confirm scoring of ventral epidural spread as observed on the lateral projection fluoroscopic images (2). We also recognize the author’s input in favor of utilizing a parasagittal technique in interventional low back pain management (4,5) in light of great controversy associated with epidural steroid injections and utilization of corticosteroids for interventional management of chronic lumbar radiculopathy. However, Ghai et al (1), when comparing results of their study with previous studies done by Manchikanti (6-11) (Table 1), failed to properly address a major difference between these studies. Instead of commenting on differences in study patients’ clinical and ethnic characteristics, they should have focused their discussion on differences between insoluble (particulate) methylprednisolone and soluble (non-particulate) betamethasone steroids. Manchikanti et al showed that lidocaine alone provides clinically significant pain relief and functional improvement regardless of whether the drug is administered as a caudal, interlaminar, or transforaminal lumbar injection (12,13). After reviewing all relevant studies by Manchikanti et al (Table 1), it is evident that addition of steroids might be superior in some patients with disc herniation as it was shown in this present study and in the most recent review (1). However, in all studies they strictly utilized betamethasone.