Comparison of fluoroscopic Guided Transforaminal Epidural Injections of Steroid and Local Anaesthetic with Conservative Management in Patients with Chronic Lumbar Radiculopathies.

BACKGROUND: Chronic lumbar radiculopathy is a common medical problem and the treatment modalities used over years have been many ranging from conservative or symptomatic management to open decompression surgery. This study was aimed at to compare two modalities of treatment, i.e., conservative and lumbar transforaminal epidural steroid injections (TFESIs).
MATERIALS AND METHODS: A total of 120 patients of American Society of Anesthesiology class - (a healthy patient or a patient with mild systemic disease) were randomized to two groups. Group C (n = 60) were managed conservatively with bed rest, analgesics, and physiotherapy. Group T (n = 60) received lumbar TFESIs with methylprednisolone 40 mg with 2 ml bupivacaine (0.5%). Measurements using visual analog scale (VAS) were taken before treatment and at various time intervals after the start of treatment.
RESULTS: There was no statistically significant difference regarding the demographic characteristics of both groups. The VAS scores were less and statistically significant in Group T after 30 min postinjection, at the 2nd week and after 1 month. Recovery rate of straight leg raise test was found to be 98% in those treated with TFESI. The Group T had significantly better patient satisfaction score and additionally there was drug dose intake reduction before and after the treatment.
CONCLUSION: Patients treated with fluoroscopic-guided TFESI have better pain relief, quality-of-life, and less analgesic requirement than those managed conservatively.

RCT Entities:   Population Interventions Outcomes

INTRODUCTION

Lumbosacral radiculopathies are a common medical, social and economic problem, with a lifetime prevalence estimated to be around 40–60%.[1] It has been an important clinical, economic, and public health problem affecting the human population worldwide. Low back pain (LBP) with radiculopathy was initially thought to be due to a nerve compression secondary to degenerative lumbar disc disease.[2] Continued study has now centered on the effects of the leakage of the contents of nucleus pulposus and the nerve supply of the annulus fibrosus. The pulposus leak releases several neuropeptides, i.e., nitric oxide, tumor necrosis factor α, metalloproteinases, the production of hyperalgesic substances such as prostaglandins, thromboxanes, leukotrienes, and so on.[3] This is further enhanced by the attraction of lymphocytes, macrophages, and other mediators of inflammation. These markers sensitize free nerve endings thus producing back pain. These components may also sensitize the adjacent and the dorsal nerve root ganglion thereby creating nerve root symptoms.

The treatment modalities used over years have been many ranging from prolonged bed rest to use of analgesics, sedatives, muscle relaxants, acupuncture injections, diathermy, electrotherapy, traction, and the final treatment being surgical decompression.[4] Every modality of treatment has its own benefits and pitfalls. Since 15 years, surgery was the treatment of choice, but recently conservative measures are preferred in the wake of unsatisfactory surgical outcomes and gravely invasive interventions.[5] In the past decades, many new minimally invasive interventional percutaneous techniques have been developed to overcome the aforementioned pitfalls and reduce the incidence for surgical decompression hence, aiming to improve the quality-of-life.[6] However, percutaneous techniques are now becoming popular as they are less invasive and eliminate the chances of postoperative infections and fibrosis.[7]

One of these minimally invasive treatment options is an injection of epidural steroids. This modality appears promising due to the benefit of delivering the drug close to the target. The use of epidural injections for the treatment of radiculopathies was first reported early in the year 1953. These epidural injections were initially performed blindly, which lacked the target specificity leading to high therapeutic failure rates. Hence, “fluoroscopic-guided” steroid injections are now becoming a modality quite promising.[8]

The drugs used usually are varying combinations of local anesthetics (LAs) and steroids. LAs exert their action through their analgesic effects by blocking the nerve conduction in on NA+ channels and suppressing the ectopic signal generation in the affected nerves. Apart from providing temporary pain relief in debilitating pain, LA may also provide prolonged benefits by putatively interrupting the vicious cycle of pain. Steroids have an anti-inflammatory effect, stabilize the neuronal membranes, suppress ectopic discharge within sensitized dorsal root ganglion nerve and have a direct effect on c-fibers.[910] Steroids mainly are classified as – particulate or nonparticulate. Steroids widely used were dexamethasone and betamethasone, which are nonparticulate steroids. However, there is enough literature suggesting the superiority of particulate steroids in the treatment of lumbar radicular pain over nonparticulate steroids.[11] The steroid being used in our study, i.e., methylprednisolone is a synthetic glucocorticoid or corticosteroid drug. Its results are good, but there has been some literature suggesting chemical arachnoiditis in a few patients which is a technical hazard of epidural steroid injection (ESI) and another being its unintended injection into an intervertebral disc.[12]

MATERIALS AND METHODS

We started conducting our study in the year 2014 after obtaining the Institutional Ethical Committee consent. The study was a retrospective randomized controlled study from May 1, 2014, to May 1, 2016.

A total of 120 patients American Society of Anesthesiology class - (healthy patient or a patient with mild, well-controlled systemic disease) in the age group 18–70 years were randomly divided by computer generated random numbers into two groups. Patients in the Group T were treated with 1 ml (40 mg) of methylprednisolone and 2 ml of 0.5% Bupivacaine via transforaminal route under fluoroscopic guidance, whereas patients in the Group C were managed on conservative lines.

Inclusion criteria included history of back pain for <1 year, age 18–70 years, patients taking analgesics such as opioids, nonsteroidal anti-inflammatory drugs (NSAIDs), or neuropathic medications such as pregabalin, LBP associated with unilateral leg pain, symptoms suggestive of sensory impairment in the affected limb, neurological imaging suggestive of spinal stenosis or herniated/degenerated disc, and patients with positive straight leg raise (SLR). Exclusion criteria included patient refusal, pregnancy/lactation, bleeding diathesis, infection at the site of injection, uncontrolled hypertension, uncontrolled diabetics, history of any surgery on spine, history of trauma to spine, sensitivity to the study drugs, bilateral radiculopathy, motor dysfunction involving bowel/bladder involvement, and evidence of compression of cauda equina.

Written and informed consent was taken from all patients. Patients were asked a detailed history about the duration of back pain, areas where the pain radiated, difficulty performing activities of daily livings and walking ability. Patients were explained in detail about the visual analog scale (VAS) and SLR test. A detailed account of the duration and type of analgesic intake was taken from the patient. A thorough back examination for any visible deformity, infection at the site of injection or previous back surgery was conducted. Before being brought to the operating room, an 18-gauge intravenous cannula was secured in the patients. Midazolam 0.5 mg intravenously was given before the procedure if required to alleviate anxiety.

In the operating room, monitors were attached (noninvasive blood pressure, SpO2, electrocardiogram) and then the patients were made to lie in prone position. Under all aseptic precautions, the skin overlying the target area was anesthetized with around 2 ml of 1% lignocaine. The level of the epidural injection was chosen depending on magnetic resonance imaging (MRI) findings and physical examination. A 22 G spinal needle was then advanced under fluoroscopic guidance aiming the needle at the superior and anterior part of the intervertebral foramen. The needle placement was confirmed after injecting 1–2 ml of isohexol, nonionic water soluble contrast medium dye, demonstrating the contrast going through the foramen. The needle position is confirmed using contrast dye which greatly reduces the possibility of misplacement or intravascular placement of the needle, which is always a risk in ESIs performed blindly. After reaching the target, the correct needle placement was confirmed both by anteroposterior [Figures 1 and 2] and lateral view [Figures 3 and 4]. In Group T patients, 2 ml of bupivacaine 0.5% mixed with 1 ml methylprednisolone (40 mg) was injected using a prefilled 5 ml syringe, the spinal needle then was withdrawn, patient repositioned and then transferred to the recovery area, where they were observed for any neurological deficit. Patients were assessed at 30 min, 2 weeks, and 1 month after the procedure.

Figure 1

Transforaminal epidural steroid injections procedure done UAAP under C-arm guidance in the Department of Anesthesiology and Pain Management, Acharya Shri Chander College of Medical Sciences, Jammu, Jammu and Kashmir, India. (Anteroposterior view).

Figure 2

The pictures are the fluoroscopic pictures of lateral and anteroposterior view while giving transforaminal epidural steroid injection in a 50 years old American Society of Anesthesiology 1 female in our hospital Acharya Shri Chander College of Medical Sciences operating room.

Figure 3

The images show the lateral and the anteroposterior views of the transforaminal epidural steroid/local anesthetic injections in our hospital Acharya Shri Chander College of Medical Sciences operating room.

Figure 4

Transforaminal epidural steroid injections procedure done UAAP under C-arm guidance in the Department of Anesthesiology and Pain Management, Acharya Shri Chander College of Medical Sciences, Jammu, Jammu and Kashmir, India. (Lateral view).

In Group C patients, the treatment included tablet tramadol 50 mg, tablet paracetamol 650 mg both thrice daily for 2 weeks and tab Pregabalin 75mg BD till the commencement of treatment. NSAIDs such as diclofenac 75 mg was given as rescue analgesic if pain not relieved by above treatment in both the groups. In addition, the patients of both groups received regular physiotherapy (short wave diathermy) and were properly taught back and leg exercises. Patients in both groups were reassessed after 2 weeks and then after 1 month.

Statistical analysis was performed using Statistical Packages for Social Science version 19 (SPSS, Inc., Chicago, IL, USA). Demographic data were compared using Chi-square test. Quantitative data were compared using unpaired t-test. Statistical significance was considered if P < 0.05.

RESULTS

None of the patients withdrew from this study. There was no statistically significant difference in two groups in terms of their demographic variables [Table 1].

Table 1

Demographics

The VAS scores were less and statistically significant in Group T after 30 min postinjection, at the 2nd week and after 1 month postinjection, with a mean ± standard deviation of 1.13 ± 0.35 with the T Group and 2.70 ± 0.88 with the C Group. The P value thus was <0.0001, which is statistically significant [Table 2].

Table 2

Visual analog scale score

The group comparison for mean VAS score at different time intervals is also shown in Figure 5. The recovery rate of SLR test was found to be 98% in those treated with transforaminal ESI (TFESI) while in the patients treated conservatively SLR recovery rate was 72%. The Group T had significantly better patient satisfaction score in T Group patients with no pain seen in 28 out of 30 patients and in the C Group, only 7 out of 30 patients had no pain seen after 1 month of management. 93.33% of the T Group patients were free of pain 1 month after the commencement of TFESI treatment whereas only 23.33% of the C Group patients had no pain after 1 month of being managed conservatively as depicted in Figure 6 [Table 3]. The P value was significant being <0.0001.

Figure 5

(a and b) Visual analog scale score showing significant improvement at 1 month of ESI (VAS-1) than the conservative treatment (VAS-3).

Figure 6

Patients satisfaction score with 92% patients having no pain 1 month post injection and 78% patients having no pain after conservative management.

Table 3

Patients satisfaction

The drug dose intake reduction before and after the treatment in the T Group was 94.33 ± 7.28% 1 month after treatment while as with the C Group it was 72.17 ± 8.78% as shown in Figure 7 which was again statistically significant with a P < 0.0001.

Figure 7

The graph depecting the drug dose intake reduction upto 95% after I month in the ESI group and only 75% in the conservative group.

L5 radiculopathy was the most commonly affected level, regardless of whether single or multiple levels were affected, in patients with disc prolapsed or spinal stenosis in this study. Postganglionic block of the L5 nerve root by L5-S1 TFESI was commonly performed.

DISCUSSION

Spinal TFESIs have been used for chronic pain management for many years. Major criticism of most of the early studies done on ESI efficacy is their use of “blind” approaches and therefore, missing the target specificity.[13] Even with skilled hands, blind epidural injections result in incorrect placement of the drug. The newer minimally invasive modalities with fluoroscopy have recently been added to the list of available treatment options for radiculopathies. Image-guided injections are more likely to place medication near to the exact target site, yielding diagnostic feedback, and maximizing the therapeutic effects.[14]

This randomized trial consisted of 120 patients treated with either TFESI or were managed conservatively with a history of persistent LBP with radiculopathy secondary to disc herniation or spinal canal stenosis. Patients of Group T showed statistically significant improvement in all parameters. At the end of 1 month, significant improvement was seen in 93% of patients in the ESI group and 23% of patients treated conservatively when all participants were included. Overall relief achieved in view of patient satisfaction was 94.33 ± 7.28 of drug dose intake reduction over a period of 1 month with three procedures when TFESI was used [Table 4]. According to the VAS score, 1.13 ± 0.35 improvement was seen in the ESI group and 2.70 ± 0.88 improvement was seen in the patients who were treated on conservative lines, which showed statistical significance. Thus, this randomized trial provides evidence that in carefully selected patients, with repeat injections, patients respond well to TFESI with a much higher level of patient satisfaction score and greater reduction in drug dose intake in the ESI group.

Table 4

Drug dose intake reduction

The decision made by pain specialists to offer a treatment and by patients to accept it often relies upon the perceived benefits, likelihood of success, and the cost of the treatment.[15] In clinical practice, there are large variations in the perceived benefits and likelihood of success of TFESI despite its relatively fewer risks and much lower cost than spinal surgery. This study attempted to show real-life practice in a tertiary care center during a given period to evaluate the diagnostic, prognostic, and therapeutic values. Lumbar radiculopathy can be well managed conservatively, though, but many patients still have persistent disabling radicular pain needing great attention in a pain specialty clinic.[161718192021] The threshold of offering TFESI as a diagnostic tool or a therapeutic adjunct to conservative treatment is variable among pain specialists, reflected by the wide variation of symptom chronicity from days to years among the sixty patients receiving TFESI in this study.[22] Other factors affecting the threshold of offering TFESI include lumbar radiculopathy not controlled by more than three different kinds of analgesic combinations in high dose acting on different pain pathways, and the diagnostic need for clinical MRI correlations, especially among patients contemplating surgery.[23]

CONCLUSION

The therapeutic portion of the injection is thus, the steroid. The steroid is magic for nerve inflammation. Someone has rightly coined the phrase “Nerves Love Steroids.”[24] Fluoroscopic guided TFESI, an injection of corticosteroid into the epidural space through the intervertebral foramen is an effective means of controlling subjective complaints and improving objective measures. It is, therefore, a reasonably safe procedure to provide short-term pain relief and allow patients to remain active with much-reduced analgesic requirement and its associated systemic side-effects.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.