Nerve root injuries in patients with chronic low back pain

The effect of transforaminal epidural steroid injections in patients with spondylolisthesis

BACKGROUND

Transforaminal epidural steroid injection (TFE) is a widely accepted non-surgical treatment for pain in patients with spondylolisthesis. However, the effectiveness of TFE has not been compared in patients with degenerative (DS) and isthmic spondylolisthesis (IS).

OBJECTIVE

To compare the effectiveness of bilateral TFEs in DS and IS.

METHODS

Patients who underwent bilateral TFEs for spondylolisthesis at University of California San Francisco Orthopaedic Institute from 2009 to 2014 were evaluated retrospectively.

RESULTS

DS patients (120 female, 51 male) were significantly older and had higher comorbidity than those with IS (18 female, 14 male). They had better pain relief after TFE than patients with IS (72.11 ± 27.46% vs 54.39 ± 34.31%; p = 0.009). The number of TFEs, the mean duration of pain relief after TFE, follow-up periods, translation and facet joint widening were similar in DS and IS groups (p > 0.05). DS group had higher successful treatment rate (66.1% vs 46.9%, p = 0.009) and longer duration of pain relief (181.29 ± 241.37 vs 140.07 ± 183.62 days, p = 0.065) compared to IS group.

CONCLUSIONS

Bilateral TFEs at the level of spondylolisthesis effectively decreased pain in patients. TFEs provided better pain relief for longer duration in patients with DS than for those with IS.

A Comparative Study of Decompressive Laminectomy and Posterior Lumbar Interbody Fusion in Grade I Degenerative Lumbar Spondylolisthesis

BACKGROUND

For Grade I degenerative lumbar spondylolisthesis (DLS), both decompression alone and decompression with fusion are effective surgical treatments. Which of the two techniques is superior is still under debate. The purpose of this study was to compare clinical outcomes after decompression alone versus decompression with fusion for Grade I DLS.

MATERIALS AND METHODS

139 patients who underwent surgery for Grade I DLS at L4-L5 were prospectively enrolled. Decompression alone was used to treat 74 patients, and decompression with fusion was used to treat 65 patients. Six patients in the first group and four patients in the second group were lost during the 2-year followup. Demographic data were recorded. Operation time, perioperative blood loss, total blood transfusion volume, and length of hospital stay were compared between the two groups. Back pain and functional outcomes were evaluated using the visual analog scale (VAS) and the Oswestry Disability Index (ODI), respectively.

RESULTS

Baseline demographic data were not different between the two groups. Operation time, blood loss, total blood transfusion volume, and length of hospital stay were all significantly greater in the fusion group than in the decompression group. This would be expected because fusion is the more invasive procedure. VAS scores were not different up until 6 months postoperatively. Twelve months after surgery, however, VAS scores were significantly lower in the fusion group. The same results were shown in terms of ODI. Although ODI decreased in both groups over time, the fusion group showed better functional outcomes than did the decompression group.

CONCLUSIONS

Although both decompression alone and decompression with fusion improved functional outcomes for Grade I DLS, fusion surgery resulted in better results compared to decompression alone. Therefore, fusion should be considered as the treatment of choice for Grade I DLS.

Validation of topographic hybrid single-photon emission computerized tomography with computerized tomography scan in patients with and without nonspecific chronic low back pain. A prospective comparative study

BACKGROUND CONTEXT

The evidence for the treatment for nonspecific chronic low back pain (ns CLBP) is very weak. Besides the complexity of the pain experience, a good biological marker or tool enabling identification of a pain generator is lacking. Hybrid imaging, combining single-photon emission computerized tomography (SPECT) with computerized tomography (CT) scan, has been proposed as useful in the diagnostic workup of patients with CLBP.

PURPOSE

To evaluate the sensitivity of SPECT-CT in patients with ns CLBP (Group I) as compared with patients without CLBP (Group II).

STUDY DESIGN

A prospective comparative study.

PATIENT SAMPLE

Two hundred patients were enrolled: 96 in Group I and 104 in Group II.

OUTCOME MEASURES

Only the physiological measurement of the incidence of hot spots was performed. The hot spots were rated as follows: 0=normal; 1=slightly colored (no hot spot on whole-body bone scan); and 2=clear hot spot (can be identified on the whole-body bone scan and confirmed on SPECT). To analyze the interobserver agreement when using this scoring system, a second independent reading was performed for 50 randomly chosen records.

METHODS

Two hundred patients divided into two groups were referred to the department of Medical and Molecular Imaging for a topographic SPECT-CT. The first group consisted of patients with ns CLBP, diagnosed by a neurosurgeon. The control group consisted of patients referred for SPECT-CT for non-spinal conditions. Hot spots were assessed for all patients. A second independent reading, blinded for the results of the first reader, was performed on 25 randomly selected patients in each group. This study was investigator initiated, and no funding was received. None of the authors or their proxies have a potential conflict of interest.

RESULTS

The odds of finding a normal image in the control group are 2.05 times higher than in Group I. The sensitivity score equals 2.37, meaning that the probability of detecting a hot spot (levels 1 or 2) is more than two times higher in Group I. When focusing on level 2 hot spots only, this score rises to 7.02, indicative of a high sensitivity.

CONCLUSIONS

Single-photon emission computerized tomography with computerized tomography might have potential in the diagnostic workup of patients with ns CLBP, owing to its higher sensitivity when compared with other advanced medical imaging modalities.

Assessment of nerve involvement in the lumbar spine: agreement between magnetic resonance imaging, physical examination and pain drawing findings

Background

Detection of nerve involvement originating in the spine is a primary concern in the assessment of spine symptoms. Magnetic resonance imaging (MRI) has become the diagnostic method of choice for this detection. However, the agreement between MRI and other diagnostic methods for detecting nerve involvement has not been fully evaluated. The aim of this diagnostic study was to evaluate the agreement between nerve involvement visible in MRI and findings of nerve involvement detected in a structured physical examination and a simplified pain drawing.

Methods

Sixty-one consecutive patients referred for MRI of the lumbar spine were - without knowledge of MRI findings - assessed for nerve involvement with a simplified pain drawing and a structured physical examination. Agreement between findings was calculated as overall agreement, the p value for McNemar's exact test, specificity, sensitivity, and positive and negative predictive values.

Results

MRI-visible nerve involvement was significantly less common than, and showed weak agreement with, physical examination and pain drawing findings of nerve involvement in corresponding body segments. In spine segment L4-5, where most findings of nerve involvement were detected, the mean sensitivity of MRI-visible nerve involvement to a positive neurological test in the physical examination ranged from 16-37%. The mean specificity of MRI-visible nerve involvement in the same segment ranged from 61-77%. Positive and negative predictive values of MRI-visible nerve involvement in segment L4-5 ranged from 22-78% and 28-56% respectively.

Conclusion

In patients with long-standing nerve root symptoms referred for lumbar MRI, MRI-visible nerve involvement significantly underestimates the presence of nerve involvement detected by a physical examination and a pain drawing. A structured physical examination and a simplified pain drawing may reveal that many patients with "MRI-invisible" lumbar symptoms need treatment aimed at nerve involvement. Factors other than present MRI-visible nerve involvement may be responsible for findings of nerve involvement in the physical examination and the pain drawing.

Degenerative spondylolisthesis: review of current trends and controversies

STUDY DESIGN

A literature-based review.

OBJECTIVES

To review management and controversies and to present authors recommendations.

SUMMARY OF BACKGROUND DATA

There is considerable controversy regarding indication for surgery, role for decompression alone, and decompression with fusion with or without instrumentation.

METHODS

Review of English language medical literature.

RESULTS

The condition may stabilize itself with the collapse of the disc spaces and osteophytes but may continue to progress in nearly a third of the cases. It may cause predominantly back pain due to segmental instability, or radicular pain/neurogenic claudication secondary to root entrapment or spinal stenosis. When conservative treatment fails, the mainstay of surgical treatment is decompressive laminectomy and fusion, with or without instrumentation.

CONCLUSIONS

Decompression primarily relieves radicular symptoms and neurogenic claudication whereas fusion primarily relieves back pain by elimination of instability. The goals for instrumentation are to promote fusion and to correct deformity. Fusion has a better long-term outcome than decompression alone. There is evidence that instrumentation improves fusion rate but does not improve clinical outcome in a relatively short-term follow-up. However, outcome of pseudarthrosis cases deteriorates over time and solid fusion produces better long-term outcome. The benefit of instrumentation comes with a price of higher postoperative morbidity and complication rate. Bone morphogenetic proteins are being tried to increase the rate of fusion, without increasing the complication rate, but the cost is prohibitive. More recently, dynamic stabilization with instrumentation but without fusion has been introduced as an alternative treatment. The current trends of surgical treatment and controversies are discussed.

When is spinal pain "neuropathic"?

Although one cannot always determine when a patient's persistent pain is neuropathic, the issues are becoming clearer. Patients with spinal pain need to be examined carefully and the persistence of pain should not necessarily be considered to indicate a continuing search for a nociceptive focus. Similarly, continuing pain following successful surgery may be caused by persistent spinal or central neurologic changes. New methods for characterizing the site of neural changes will develop--functional MRI and PET scanning are now characterizing brain activity and will possibly yield results soon that will be helpful in the clinic. Further work needs to be done to identify which clinical features lead to better responses to agents for the treatment of neuropathic pain. New, more specific agents with actions focused on the specific parts of neural transmission are being developed. These include agents (such as growth factors) that will cure, not just suppress, the pathologic pain generators and pathways in patients with persistent pain.