Lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis

Quantifying Lumbar Foraminal Volumetric Dimensions: Normative Data and Implications for Stenosis-Part 2 of a Comprehensive Series

INTRODUCTION

Lumbar foraminal stenosis (LFS) occurs primarily due to degenerative changes in older adults, affecting the spinal foramina and leading to nerve compression. Characterized by pain, numbness, and muscle weakness, LFS arises from structural changes in discs, joints, and ligaments, further complicated by factors like inflammation and spondylolisthesis. Diagnosis combines patient history, physical examination, and imaging, while management ranges from conservative treatment to surgical intervention, underscoring the need for a tailored approach.

MATERIALS AND METHODS

This multicenter study, conducted over six years at a tertiary hospital, analyzed the volumetric dimensions of lumbar foramina and their correlation with nerve structures in 500 patients without lumbar pathology. Utilizing high-resolution MRI with a standardized imaging protocol, eight experienced researchers independently reviewed the images for accurate measurements. The study emphasized quality control through the calibration of measurement tools, double data entry, validation checks, and comprehensive training for researchers. To ensure reliability, interobserver and intraobserver agreements were analyzed, with statistical significance determined by kappa statistics and the Student's t-test. Efforts to minimize bias included blinding observers to patient information and employing broad inclusion criteria to mitigate referral and selection biases. The methodology and findings aim to enhance the understanding of normal lumbar foramina anatomy and its implications for diagnosing and treating lumbar conditions.

RESULTS

The study's volumetric analysis of lumbar foramina in 500 patients showed a progressive increase in foraminal volume from the L1/L2 to the L5/S1 levels, with significant enlargement at L5/S1 indicating anatomical and biomechanical complexity in the lumbar spine. Lateral asymmetry suggested further exploration. High interobserver and intraobserver agreement levels (ICC values of 0.91 and 0.95, respectively) demonstrated the reliability and reproducibility of measurements. The patient cohort comprised 58% males and 42% females, highlighting a balanced gender distribution. These findings underscore the importance of understanding foraminal volume variations for lumbar spinal health and pathology.

CONCLUSION

Our study significantly advances spinal research by quantifying lumbar foraminal volumes, revealing a clear increase from the L1/L2 to the L5/S1 levels, indicative of the spine's adaptation to biomechanical stresses. This provides clinicians with a precise tool to differentiate between pathological narrowing and normal variations, enhancing the detection and treatment of lumbar foraminal stenosis. Despite limitations like its cross-sectional design, the strong agreement in measurements underscores the method's reliability, encouraging future research to further explore these findings' clinical implications.

Does the Severity of Foraminal Stenosis Impact Outcomes of Lumbar Decompression Surgery?

OBJECTIVE

To establish the relationship between the magnitude of foraminal stenosis and 1) improvement in patient-reported outcomes, 2) improvement in motor function after lumbar decompression surgery, and 3) difference in surgical outcomes.

METHODS

Patients who underwent one-level posterior lumbar decompression for radiculopathy were retrospectively identified. Patient demographics and surgical characteristics were collected through a query search and manual chart review of the electronic medical records. Foraminal stenosis was determined on magnetic resonance imaging and graded using Lee et al.'s validated methodology as none, mild, moderate, or severe. Surgical outcomes, motor function, and patient-reported outcome measures (PROMs) were compared based on the amount of stenosis (mild vs. moderate vs. severe). Bivariant and multivariant analyses were performed.

RESULTS

Severe stenosis demonstrated more 90-day readmissions (0.00% vs. 0.00% vs. 8.57%, respectively, P = 0.019), though this effect did not remain significant on multivariate analysis (P = 0.068). There was no association between stenosis severity and the degree of functional impairment or PROMs preoperatively. Patients with moderate or severe preoperative foraminal stenosis showed improvement in all PROMs after surgery (P < 0.05) except the mental component of the Short Form 12 survey. Notably, central stenosis grade was insignificantly different between groups (P = 0.358). Multivariable logistic regression analysis did not identify any significant independent predictors of surgical outcomes or changes in PROMs.

CONCLUSIONS

We demonstrated that regardless of foraminal stenosis severity preoperatively, patients have a similar improvement in PROMs, surgical outcomes, and restoration of motor function after lumbar decompression surgery for radiculopathy.

The Influence of Rheumatoid Arthritis on Higher Reoperation Rates over Time Following Lumbar Spinal Fusion-A Nationwide Cohort Study

This study aimed to compare the rates of reoperation over time following first lumbar fusion in rheumatoid arthritis (RA) patients and non-RA patients. This study was conducted using Korean Health Insurance Review and Assessment (HIRA) data. We identified the RA group as 2239 patients who underwent their first lumbar fusion with RA and the control group as 11,195 patients without RA. This reflects a ratio of 1:5, and the participants were matched by sex, age, and index surgery date. The index dates were between 2012 and 2013. When comparing the rate of patients undergoing reoperation, the adjusted HR was 1.31 (95% CI: 1.10−1.6) in the RA group (p = 0.002). In terms of the three time intervals, the values in the time frames of <3 months and 3 months−1 year were not statistically significant. However, at 1 year post-surgery, there was a higher risk of reoperation in the RA group, as demonstrated by the Kaplan−Meier cumulative event analysis. This higher risk of reoperation continued to increase throughout 5 years of follow-up, after which it was stable until the last follow-up at 7 years. This population-based cohort study showed that the RA patients had a 1.31 times higher risk of reoperation following lumbar fusion than did the controls. This difference was more pronounced at 1 year post-surgery.

Surgical Management of the Lumbar Spine in Rheumatoid Arthritis

STUDY DESIGN

Narrative review.

OBJECTIVE

To provide an overview on the diagnosis and surgical management of rheumatoid involvement of the lumbar spine. Rheumatoid arthritis (RA) is a chronic inflammatory disease of synovial joints, most commonly appendicular followed by axial. Although cervical spine involvement of RA is well documented, data on lumbar spine involvement and surgical management remains limited.

METHODS

Using PubMed, studies published prior to November 2018 with the keywords "RA, etiology"; "RA, spine management"; "RA, surgical management"; "RA, treatment"; "RA, DMARDs"; "RA, lumbar spine"; "RA, spine surgical outcomes"; "RA, imaging" were evaluated.

RESULTS

The narrative review addresses the epidemiology, manifestations, imaging, surgical complications, and operative and nonoperative management of RA involvement of the lumbar spine.

CONCLUSIONS

Rheumatoid involvement of the lumbar spine can present with lower back pain, neurogenic claudication, radiculopathy, spinal deformity, and instability. Patients with RA have significantly higher rates of vertebral fractures and complications following surgical intervention. However, in the setting of instability and spinal deformity, thoughtful surgical planning in conjunction with optimal medical management is recommended.

The Relationship Between Demographic Characteristics and Noninflammatory Complaints in Rheumatoid Arthritis Patients on Remission

OBJECTIVES

The aim of this study was to investigate the noninflammatory complaints in rheumatoid arthritis (RA) patients on remission and the relationship between these complaints and disease characteristics.

METHODS

This is a medical records review study of 103 RA patients who sustained a remission period for at least 6 months. Clinical features and demographic characteristics of patients, such as laboratory parameters, current number of sensitive and swollen joints, pain level and Patient Global Assessment, previously used medications, and modified Health Assessment Questionnaire, were carefully recorded. Patients were divided into 2 groups according to the presence of noninflammatory complaints as patients with or without noninflammatory complaints (group 1, n = 56; group 2, n = 47, respectively).

RESULTS

The most common complaints with a decreasing frequency were as follows: low back pain (n = 13 [23.2%]), degenerative knee pain (n = 11 [19.6%]), and widespread body pain due to fibromyalgia (n = 7 [12.5%]). The mean age and age at diagnosis were higher in group 1 than in those in group 2 (p = 0.039, and p = 0.014, respectively).

CONCLUSIONS

Noninflammatory complaints can be observed in about 50% of RA patients on remission. These complaints were more common in elderly patients with old-age disease onset. Therefore, while evaluating and treating this patient population, noninflammatory complaints and disease-specific parameters should be considered carefully in order to fully improve the clinical outcomes.

The pitfalls in surgical management of lumbar canal stenosis associated with rheumatoid arthritis

There have been few clinical studies in the area of cervical spine that focused on surgery for treating degenerative lumbar disease in patients with rheumatoid arthritis (RA). High rates of wound complications and instrumentation failure have been reported more for RA than for non-RA patients, although clinical outcomes are similar between the two groups. Lumbar canal stenosis in RA is caused not only by degeneration but also by RA-related spondylitis, which includes facet arthritis and inflammation around the vertebral endplate. The pitfalls in surgical management of lumbar canal stenosis in RA patients are highlighted in this study. The study reviewed 12 patients with RA,who were surgically treated for lumbar canal stenosis. Two out of five patients with pulmonary fibrosis died of worsened pulmonary condition, even though there were no perioperative pulmonary complications. Two patients with pedicle screw fixation showed no instrumentation failure, but two patients with spinous process fixation needed re-operation or vertebral fracture. Surgical treatment for lumbar canal stenosis in RA patients needs to be individually adjusted. Preoperative assessments and treatments of pulmonary fibrosis and osteopenia are essential. Surgery for lumbar canal stenosis with RA should be deferred for patients with advanced pulmonary fibrosis because of its potential life-threatening risk. Fusion surgery is indicated only in patients with kyphosis or severe symptoms caused by intervertebral instability. Pedicle screw fixation with hydroxyapatite granules or sublaminar tape is recommended. Closer follow-up after surgery is necessary because of possible delayed wound infection, instrumentation failure, pathological fracture, and respiratory deterioration.