|Year : 2016 | Volume
| Issue : 2 | Page : 127-131
Study of nerve root block procedure as a diagnostic and therapeutic aid in lumbosacral radiculopathy
Rahul Madhukar Salunkhe, Tushar Pisal, Yuvraj Singh Hira, Ashutosh Singh, Jay Janakbhai Patel, Sunny Sajitsing Goud
Department of Orthopaedics, Dr. D. Y. Patil Medical College and Research Center, Pune, Maharashtra, India
|Date of Web Publication||18-Jul-2016|
Rahul Madhukar Salunkhe
Department of Orthopaedics, Dr. D. Y. Patil Medical College and Research Center, Pimpri, Pune - 411 018, Maharashtra
Source of Support: None, Conflict of Interest: None
Introduction: Backache and sciatic pain are routinely seen in day-to-day practice. In all urban settings with changed lifestyle, lack of exercise, bad posture, excessive use of vehicles, and disturbed nutrition; problem of discogenic backache and sciatica is on the rise. The treatment modalities vary from conservative to surgical methods, but they predominantly provide relief to leg pain and not back pain. Nerve root block acts at these inflammatory processes, by the action of the steroid and thus decreasing the chemical irritation to the nerve roots. Furthermore, there is a decrease in sensitization of dorsal horn neurons by bupivacaine. Aims and Objectives: To evaluate diagnostic and therapeutic efficacy of root block procedure. To study relief in terms of pain alleviation, activities of daily living, and straight leg raising (SLR) restriction. Materials and Methods: Retrospective study of fifty patients of sciatic radiculopathy between the ages of 20 and 60 years were evaluated under this study at Dr. D. Y. Patil Medical College and Research Centre, Pune. All the patients of different age and sex had radicular pain with or without back pain, restricted spinal mobility, positive active and passive SLR test, and other nerve tension signs. Results: Out of fifty patients selected after thorough clinical and radiological examination, 45 (90%) had enjoyed complete pain relief and 31 (62%) of which were completely symptom-free at the end of 1 year. Conclusion: Spinal nerve root block may provide lasting therapeutic benefit, allowing the patient to participate in physical therapy and early return to routine activities saving working manpower hours.
Keywords: Low back ache, nerve root block, sciatica
|How to cite this article:|
Salunkhe RM, Pisal T, Hira YS, Singh A, Patel JJ, Goud SS. Study of nerve root block procedure as a diagnostic and therapeutic aid in lumbosacral radiculopathy. Indian J Pain 2016;30:127-31
|How to cite this URL:|
Salunkhe RM, Pisal T, Hira YS, Singh A, Patel JJ, Goud SS. Study of nerve root block procedure as a diagnostic and therapeutic aid in lumbosacral radiculopathy. Indian J Pain [serial online] 2016 [cited 2020 Dec 2];30:127-31. Available from: https://www.indianjpain.org/text.asp?2016/30/2/127/186470
| Introduction|| |
Epidural injections have a long history of efficacy and safety in treating low back pain and lower extremity pain since 1901.  Since its first description by Mixter and Barr in 1934,  lumbar disc herniation is one of few abnormalities, where clear relationship between the morphological alteration and pain seems to exist. Previously, mechanical compression was considered as a cause of sciatica, but there is increasing evidence that chemical irritation of the nerve root plays an important role. , Throughout the past century, the most popular treatment modalities in treating low back pain have been caudal, interlaminar, and transforaminal epidural injections. ,,,,,,,,,
Aims and objectives
To evaluate diagnostic and therapeutic efficacy of selective nerve root block (SNRB) procedure and to study relief in terms of pain alleviation, activities of daily living, and straight leg raising (SLR) restriction.
| Materials and Methods|| |
Fifty patients of sciatic radiculopathy between the ages of 20 and 60 years were evaluated under this study. All the patients of different age and sex had radicular pain with or without back pain, restricted spinal mobility, positive active and passive SLR test (SLRT), and other nerve tension signs. None of the subjects under study had any sensory or motor deficit or abnormal reflexes. All the patients were given a fair trial with conservative management in the form of rest, analgesics, traction, and muscle relaxants for a minimum of 1 month before undertaking the procedure. Most of the patients had monoradiculopathy with unilateral involvement, but a small amount of the population had polyradiculopathy or bilateral involvement.
The inclusion criteria were:
The exclusion criteria were:
- Age 20-60 years
- All patients with complaint of low backache with radiculopathy, unilateral, or bilateral
- Not relieved by analgesics or physiotherapy
- Lumbosacral radicular pain as a result of prolapsed intervertebral disc
- Positive SLRT
- Acute phase patients preferred to chronic.
- Age more than 60 years
- Patients with claudication and with facetal arthropathy
- Extruded disc seen on magnetic resonance imaging (MRI)
- Patients with motor deficit
- Failed back syndrome
- Systemic disease such as diabetes or any other source of infection.
A volume of 1 cc (40 mg) of methylprednisolone (Depo-Medrol), 1 cc of 2% xylocaine, 23G spinal needle, isoionic contrast (Omnipaque), 10 cc (20 g) syringe with needle, and C-arm fluoroscope.
Patient positioning [Figure 1] - prone on a radiolucent table, with C-arm fluoroscope on the side opposite to the affected limb, and the surgeon positioned on the affected side, anteroposterior (AP) and lateral views obtained with the C-arm, to obtain a clear view of the spinous processes, disc spaces, and pedicle at the level determined clinicoradiologically. Markings are made over the spinous process in the midline (AP view). Disc spaces in AP and lateral view and pedicle in the AP and lateral view. Local infiltration with 2% xylocaine done in the superficial and muscular planes at and around the entry point [Figure 2]. Long spinal needle 23G directed at 45°, introduced from the entry point marked before, aiming at upper part of neural foramen beneath the pedicle, under fluoroscopic control in the triangle of safety [Figure 3]. Perineurosheathogram [Figure 4] and [Figure 5] is seen after dye injection. Christmas tree appearance is seen at the sacral level [Figure 6]. The drug is then injected [Figure 7].
| Results|| |
Immediately after the injection, each patient recorded his\her back and leg pain on a 10 visual analog scale. Immediately, SLRT is also carried out and recorded [Figure 8]. Subsequent estimation in a similar manner was done on day 3, day 7, at 4 weeks, and at the end of 3 months. The results were assessed using the following criteria and documented as excellent, good, fair, or poor.
In our series, we studied fifty cases of sciatic radiculopathy secondary to prolapsed intervertebral disc, confirmed by clinical and radiological examination. Transforaminal injection of 2% xylocaine and Depo-Medrol into the peridural sleeve was given under fluoroscopic control in the selected group of fifty patients. The selection of subjects was based on a uniform inclusion and exclusion criteria as described in detail above. The subjects were followed up at days 3, 7, at 4 weeks, and at 3 months.
In our study, results were analyzed on ten visual analog score 41 (82%) of patients enjoyed excellent results, 4 (8%) had good results, fair results were seen in 2 (4%), and poor results were seen in 3 (6%). Patients with poor results required surgical decompression at the end of 3-month time period. Other patients had complete pain relief at 3 months.
Pain at injection site, which responded to application of ice packs and it was observed in 8 patients out of sample size of 50, along with it, we encountered transient hypoesthesia in the area corresponding to the dermatome at which the block was given, in one patient, and transient hyperesthesia in the area corresponding to the dermatome at which the block was given, in one patient.
| Discussion|| |
Nerve root block was the term first developed to describe the technique for diagnosing the source of radicular pain when imaging studies suggested possible compression of several roots. Early studies of selective nerve root injections described an extraforaminal approach, in which the needle is advanced at right angles to the spinal nerve outside the neuroforamina, thus relying upon leg pain provocation, presumably resulting from penetration of the nerve by the needle. 
Macnab first described SNRBs in 1971.  Infiltration performed with contrast agent and lidocaine aimed to differentiate different sources of leg pain in an equivocal clinical situation.  Frequently, it is not possible to exactly localize the compromised nerve root either by clinical neurological examination or by imaging studies. This is particularly true for multilevel nerve root compromise as shown by MRI. There is increasing evidence that there is no close correlation between imaging findings and clinical symptoms.  Midline epidural technique was introduced by Pages in 1921. 
Literature has shown that nerve root block is helpful in diagnosis in cases where close correlation is missing clinically and radiologically. ,,,,, In the event of a positive response (i.e., resolution of leg pain), the nerve root block allows the diagnosis of the affected nerve root with a sensitivity of 100% in cases with disc protrusions and with a positive predictive value of 75-95% in cases of a foraminal stenosis. ,,,,, In our study, SNRB provided conclusive evidence in 45 (90%) out of fifty subjects under study, in ascertaining the level of offending disc causing radicular pain. This was especially beneficial in those subjects who had evidence of multilevel prolapsed intervertebral disc, and clinical correlation was doubtful.
Weiner and Fraser  in a prospective study investigated the success of nerve root blocks in thirty patients with foraminal and extraforaminal disc herniation. They found an immediate pain relief in 27 patients, of whom only three required surgery because of recurrent leg pain, while two individuals were lost to follow-up. In total 22 of 28 patients (79%) had a substantial and permanent pain reduction during a 1-10 years follow-up. In our study, 41 patients (82%) had excellent result, 4 (8%) patients had good result, 2 (4%) patients had fair, and 3 (6%) had poor results. All three patients with poor results required surgical decompression at the end of 3-month time period.
Weber  concluded in a study that the main drawback of the nonoperative treatment (physiotherapy and medication) is the slow recovery and that the patients are disabled for a prolonged period of time.
| Conclusion|| |
SNRBs, when combined with a careful history, physical examination, and quality radiographic studies, are an important tool in the diagnostic evaluation and treatment of patients with predominant radicular symptoms. Reproduction and temporary relief of a patient's leg pain provide useful diagnostic and prognostic information, confirming clinical and radiographic findings. In addition, the SNRB may provide lasting therapeutic benefit, allowing the patient to participate in physical therapy and early resumance of routine activities saving working manpower hours. Fluoroscopically controlled delivery of local anesthetic and steroid to the exact area of presumed pathology is a logical choice when confirmatory information is essential.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8]