Utility Of MRI In Guiding Surgical Decisions for
Sciatica Related To Disc Issues
The utilization of magnetic resonance imaging (MRI) is essential for diagnosing and formulating treatment plans for intervertebral disc herniations. It is the preferred imaging modality for suspected lumbar disc herniation and severe sciatica symptoms.
Qualitative MRI Findings and Their Association with Sciatica
Qualitative MRI findings, including the identification of disc extrusion or nerve root compression, exhibit a significant association with sciatica. MRI enables precise measurements of disc herniation size, shape, and dimensions of the spinal canal.
However, the available data on the predictive value of MRI assessments in guiding decisions between surgical or nonsurgical management for sciatica is limited.
The findings from a randomized controlled trial comparing early surgery to prolonged conservative care for patients with sciatica lasting 6 to 12 weeks were previously reported.
Comparison of Early Surgery vs. Prolonged Conservative Care
While early surgery led to quicker relief of symptoms compared to conservative care, the outcomes were similar after 1 year of follow-up. Surprisingly, 39% of patients in the conservative care group still underwent surgery within the first year due to ongoing or worsening leg pain and progressive neurological issues.
Previous research indicated that patients with higher initial levels of leg pain intensity or disability scores had a greater likelihood of eventually requiring surgery.
The study reported by literature aimed to assess the predictive value of qualitative and quantitative MRI assessments for delayed surgery in patients with sciatica.
The researchers wanted to determine if early in the course of sciatica, specific MRI evaluations could accurately predict which patients would ultimately undergo surgery during follow-up.
Such predictive information could be valuable for patients and physicians, as it would allow for early consideration of surgery to minimize the duration of suffering and avoid unnecessary delays.
Study Objective: Assessing MRI’s Predictive Value for Delayed Surgery
In the same study, out of 142 patients who received prolonged conservative care, 39% (55 patients) eventually opted for surgery. The average time until surgery was 18 weeks, with varying proportions of patients undergoing surgery within different time intervals.
The baseline characteristics, including age, sex, duration of sciatica, body mass index, and disc herniation level, were similar between the group that had delayed surgery and the group that did not undergo surgery.
The presence of nerve root compression and vertebral endplate signal changes showed no significant differences between the two groups. The distribution of large disc herniations and central/subarticular disc herniations was comparable among those who underwent surgery and those who did not.
However, extruded disc herniations were more frequently observed in the surgically treated group (59%) compared to the conservatively treated group (70%). The size of the herniation at baseline was similar between the surgical and nonsurgical groups, with no significant difference observed.
However, the size of the dural sac was smaller in the surgical group compared to the nonsurgical group. The ratio of the disc herniation size to the dural sac size did not significantly differ between the two groups.
The remaining spinal canal size was smaller in the surgical group compared to the nonsurgical group, and there was no significant difference in the ratio of the disc herniation size to the remaining spinal canal size between those who underwent surgery and those who did not.
In the surgical group, baseline scores for the RDQ (Roland-Morris Disability Questionnaire) and VAS (Visual Analog Scale) leg pain were higher compared to the nonsurgical group.
Upon conducting a subanalysis, significant differences were found in the baseline RDQ and VAS scores, as well as in the sizes of the dural sac and remaining spinal canal between patients who did not undergo surgery, those who underwent surgery within 6 months after conservative care assignment, and those who underwent surgery between 6 and 12 months after assignment.
The researchers evaluated the predictive value of different factors for surgery using the area under the ROC curve (AUC). The AUC values were calculated for the size of the dural sac, size of the spinal canal, VAS leg pain score, and RDQ score.
Combining the MRI variables resulted in a certain AUC value, and combining the RDQ score and VAS leg pain score yielded another AUC value. Finally, when all four variables were combined, a higher AUC value was obtained. These results suggest that these factors have some predictive value for the likelihood of undergoing surgery.
Clinical Outcomes and Factors Affecting Surgery Decisions
Clinical outcome scores did not show any significant differences between the surgical and nonsurgical groups after one year of randomization. However, the incidence of disc herniation was higher in the nonsurgical group.
Among the surgical patients, the presence or absence of nerve root compression at baseline did not have a notable impact on the perceived recovery at the one-year follow-up.
Baseline MRI assessments and the size of disc herniation were not successful in anticipating the necessity for surgery among sciatica patients following a conservative management approach.
Nonetheless, patients who ultimately underwent surgery displayed higher RDQ scores, more severe leg pain, and smaller dural sacs and spinal canals at baseline compared to those who did not require surgery.
Hence, MRI lacks reliability in differentiating between sciatica patients who will or will not undergo surgery.
Acute sciatica often resolves spontaneously within 18 weeks, and surgery is considered when conservative care fails. Absolute indications for surgery are rare, and clear clinical guidelines are lacking for other cases.
Retrospective studies suggest that patients undergoing surgery for sciatica tend to have larger disc herniations and smaller spinal canals, but these studies have limitations and potential biases.
Surgical treatment rates for lumbar discectomy vary widely, and there are no objective measures available to determine when to perform surgery for sciatica. Factors such as pain, disability, psychological aspects, and personal preferences play a role in the decision-making process.
The study found no significant predictive value of MRI for future surgery in patients with 6 to 12 weeks of sciatica. Reliable tools for patient selection in disc surgery are still needed.
At the one-year follow-up of the clinical trial, a significant proportion of patients still displayed visible disc herniation on MRI, regardless of their treatment. However, the presence of MRI abnormalities did not differentiate between patients experiencing persistent or recurrent sciatica symptoms and those without symptoms.
Other studies have reported similar findings, indicating a limited connection between MRI findings and clinical outcomes. Nonetheless, microsurgical discectomy has demonstrated effectiveness in treating sciatica patients
In discussions regarding the decision between surgery and a wait-and-see approach for sciatica, MRI should primarily be used to assess anatomical features and the level of a herniated disc for surgical planning.
However, MRI demonstrated limited ability to differentiate between patients who underwent delayed surgery and those who did not require surgery during the follow-up period.
Do you have more questions?
Can sciatica cause knee pain?
Sciatica pain is usually radiated along the back or the side of the thigh and knee into the leg. Occasionally, patients may present with a confusing picture of knee problem, but maybe having sciatica. A thorough history and examination by the physician as well as diagnostic tests in the form of x-rays and MRI may be needed to confirm the diagnosis.
How to fix sciatica nerve pain?
Sciatica nerve pain can be relieved to various modalities. To start with, antiinflammatory medications like ibuprofen, naproxen or Tylenol may help. If pain is not relieved with the medications, physical therapy, chiropractor and acupuncture may also help. The patient may also take medications including gabapentin or pregabalin for pain relief.
The patient should take a short period of bed rest for a day or two. The patient should continue to do normal usual activities. If the pain is not relieved, he should see his doctor. Epidural injection or nerve root blocks may help in relieving the sciatica pain. Patients who are not having any relief with any of the above-mentioned treatment plans, may need an MRI for confirmation of diagnosis and possibly surgery to relieve their pain.
How do you diagnose sciatica?
Sciatica is a clinical diagnosis, which can be corroborated by imagings with or without nerve conduction/EMG studies. Typical patient will present with pain radiating down one leg along the back or the side of the thigh index. They may have been associated with tingling and numbness or back pain.
Occasionally, patients may have weakness in the toes or the ankle. Once the clinical diagnosis is made, confirmation can be done using x-rays and MRI. In patients who have a confusing picture due to underlying comorbidity or atypical presentation, nerve conduction study and electromyographic study can be done to further confirm or rule out sciatica.
Is heat or ice better for sciatica?
Heat is usually better in patients who have sciatica, though patients who are not relieved with heat should also try ice or occasionally rhythmic use of heat and ice, cyclic use of heat or ice may help better than one alone.
Does massage help sciatica?
Massage is one of the modalities of adjuvant therapy for sciatica can be helpful and can decrease pain by strengthening the muscles as well as stretching the nerves. Deep massage can also help decrease the muscle spasms that develop in patients with sciatica.
Where to put an ice pack for sciatica?
For sciatica, an ice pack or even a heating pad can be used by placing it into the lower back and the gluteal region. It helps decrease the inflammation of the nerve there and thereby decreasing the pain and associated symptoms.
Does the inversion table help sciatica?
Inversion table similar to traction helps sciatica by increasing the height of the disk and thereby allowing the disk to go back into space thereby decreasing the compression of the nerve root may help in decreasing the pain of sciatica. The issue of inversion table as well as traction is that this is effective until the patient uses them and once the patient is upright and moving, the effect of the inversion table or the traction may not be persistent.
Can the sciatica cause ankle pain?
Sciatica or lumbar radiculopathy causes pain radiating from the back or the hip into the lower extremities down the leg. The pain radiates along the back or the side of the thigh and leg and radiates down foot. An isolated ankle pain may not be caused by radiculopathy. If the pain is on outer or inner side of the ankle and is radiating down or coming from the top then it may be associated with sciatica or lumbar radiculopathy.
Does sciatica get worse before it gets better?
90% of patients with sciatica will eventually get better in a period of four to six weeks. During this time, the pain may worsen also or it may keep on improving. Patients who have severe pain with or without tingling or numbness usually will need medical attention to relieve their pain during this duration. The treatment may involve medications, physical therapy and cortisone shots. Patients who have sudden onset of neurological deficit or weakness or worsening of the neurological deficit may need surgery also.
Can stress cause sciatica?
Sciatica like any other neurologic pain can have relation with the mental status and cognitive functions of the person. Though stress may directly not be the causative factor for sciatica, it may have its effect on the severity as well as course of the disease process of sciatica. Patients with high stress levels may have difficulty coping with sciatica and may take longer time to get better.
What happens if sciatica left untreated?
Sciatica in most patients will get better by itself in a period of four to six weeks. The pain as well as tingling and numbness tend to improve over time, though it may have periods of worsening. Patients may need treatment in the form of medications or injections to relieve the pain, so as to spend this period of four to six weeks, till then the relief is evident.
Occasionally in about 10% of the patients, there will be no relief, worsening or recurrence of sciatica pain despite all treatment modalities over four to six weeks. These patients may need surgical management to relieve their pain due to the pressure over the nerve roots.
Can sciatica be a serious disorder?
Sciatica is usually self limiting in 90% of patients and only needs treatment in the form of medication and physical therapy and occasionally cortisone injection. In about 10% of patients, this may not be relieved by any modality and these patients may need to undergo surgical treatment.
Sciatica can also rarely lead to rapid neurological deficit presenting in the form of cauda equina syndrome, which can be potentially disabling. The neurological deficit caused due to cauda equina syndrome may be permanent especially if not treated early in the disease process. Such patients may not only have weakness in their legs, but may also lose control over their bowel and bladder, which may or may not recover over time.
What are the medication that can help sciatica?
Sciatica pain can be relieved by the help of anti-inflammatory medications like ibuprofen, naproxen. It can also be helped by Tylenol. Stronger pain medications like tramadol and narcotic medications may occasionally be needed for a short period of time.
Neuromodulator medications like gabapentin and pregabalin may also be helpful in decreasing the sciatica pain. Occasionally, medications like amitriptyline, duloxetine and carbamazepine may also be used in some patients to relieve their pain.
Is the back brace helpful for sciatica pain?
Back brace may be helpful in patients who have back pain with or without sciatica. Patients who have only radicular pain in their lower extremity may not be helped by the back brace. Use of back brace for a long period of time may be detrimental by causing atrophy of the back muscles.
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