Assessing the Agreement Between Radiologic and Clinical Measurements of Lumbar and Cervical Epidural Depths in Patients Undergoing Prone Interlaminar Epidural Steroid Injection

Incidence and risk factors for complications following cervical epidural steroid injections

BACKGROUND CONTEXT

Cervical epidural steroid injections (CESIs) are commonly used in management of cervical pathology. While severe complications have been reported, they are rare, and thus their incidence and risk factors have not been well characterized.

PURPOSE

To determine the incidence of complications 7, 30, and 90 days after CESI and to identify associated risk factors.

STUDY DESIGN

Retrospective cohort study of a large, national administrative claims database (MeritiveTM Marketscan®).

PATIENT SAMPLE

The study included 229,412 patients (mean age 52.2 ± 11.3 years, 57.1% female) undergoing 448,209 CESIs from 2008 to 2015.

OUTCOME MEASURES

Complication rates following CESI, and risk factors for complication.

METHODS

Adults undergoing a CESI with active enrollment for one year prior to and 90 days after CESI were included. Patients with neoplasm, fracture, infection, inflammatory spondyloarthropathy or prior cervical surgery within one year preceding CESI were excluded. Multivariable repeated measures logistic regression models were used to identify risk factors for complications at 7, 30, and 90 days. Complications were stratified into procedural and medical complications. Each time point was modeled separately with Bonferroni adjustment for the multiple time points.

RESULTS

Complications increased from 1.7% to 4.1%, to 8.0% within 7, 30, and 90 days, respectively. Procedural complications occurred in 0.6% of cases within 7 days, with neurologic complications occurring in 0.5% of cases. Medical complications occurred in 1.1%, 3.6%, and 7.2% within 7, 30 and 90 days, respectively. After multivariable risk adjustment, a transforaminal approach was associated with greater odd for procedural complications within 7 days relative to an interlaminar approach (p<.001), with an odds ratio (95% confidence interval) of 1.55 (1.35, 1.77). The transforaminal approach also was associated with greater odds of neurologic complications at 7 days [1.69 (1.45, 1.95); p<.001]. A myelopathy diagnosis was not associated with risk of overall, procedural, medical, or neurological complications. The most influential factors independently associated with greater odds of any complication within 30 days included anticoagulant prescription [5.40 (4.55, 6.41); p<.001] and history of venous thromboembolism [3.01 (2.40, 3.77); p<.001]. The factors most strongly associated with procedural complications at 7 days included history of neurologic deficit [3.04 (2.65, 3.50); p<.001] and antiplatelet medication prescription [2.21 (1.49, 3.27); p=.003].

CONCLUSIONS

Complications following CESIs are infrequent. Neurologic complications were most common among procedural complications at 0.5% at 7 days. The transforaminal approach was associated with higher procedural complication rate compared to the interlaminar approach. Procedural and neurological complications were also associated with multiple factors including obesity, existing neurologic deficit, anxiety, and antiplatelet medication prescription. Attention should be given to these factors to mitigate procedural complications.

Correlation between epidural space depth measured with ultrasound and MRI compared to clinical loss of resistance when performing lumbar epidural steroid injection

BACKGROUND

This prospective study assessed the accuracy of MRI and ultrasound (US) measurements as a preprocedural assessment tool for predicting clinical loss of resistance depth (CLORD) during fluoroscopy-guided lumbar epidural steroid injections (ESIs).

MATERIALS AND METHODS

Sixty patients enrolled received lumbar ESIs at an academic chronic pain clinic. The MRI measurement calculated the distance between the skin and the posterior epidural space, while US measurements included transverse and parasagittal oblique views of the interlaminar space. The epidural space measurements were compared with the CLORD during the performance of the prone epidural injections. The differences in measurements were analyzed using two one-sided tests for equivalency with a 0.5 equivalency margin. The intraclass correlation coefficients between CLORD and the imaging modalities were estimated using mixed effects models.

RESULTS

MRI was equivalent to CLORD with a mean difference of -0.2 cm (95% CI -0.39 to -0.11). US transverse and US parasagittal oblique measurements were not equivalent to and underestimated CLORD with mean differences of -0.98 cm (90% CI -1.8 to -0.77) and -0.79 cm (90% CI -1.0 to -5.9), respectively. The intraclass correlation coefficients between MRI and CLORD were the highest at 0.85, compared with 0.65 and 0.73 for transverse and parasagittal oblique US views, respectively.

CONCLUSIONS

MRI measurements are preferable over US for preprocedural assessment of patients receiving lumbar ESIs for predicting CLORD.

Relationship between needle depth for lumbar transforaminal epidural injection and patients' height and weight using magnetic resonance imaging

Background

Optimal needle depth in transforaminal epidural injection (TFEI) is determined by body measurements and is influenced by the needle entry angle. Physician can choose the appropriate needle length and perform the procedure more effectively if depth is predicted in advance.

Methods

This retrospective study included patients with lumbosacral pain from a single university hospital. The skin depth from the target point was measured using magnetic resonance imaging transverse images. The depth was measured bilaterally for L4 and L5 TFEIs at 15°, 20°, and 25° oblique angles from the spinous process.

Results

A total of 4,632 measurements of 386 patients were included. The lengths of the left and right TFEI at the same level and oblique angle were assessed, and no statistical differences were identified. Therefore, linear regression analysis was performed for bilateral L4 and L5 TFEIs. The R-squared values of height and weight combined were higher than the height, weight, and body mass index (BMI). The following equation was established Depth (mm) = a – b (height, cm) + c (weight, kg). Based on the equation, maximal BMI capable with a 23G, 3.5-inch, Quincke-type point spinal needle was presented for three different angles (15°, 20°, and 25°) at lumbar levels L4 and L5.

Conclusions

The maximal BMI that derived from the formulated equation is listed on the table, which can help in preparations for morbid obesity. If a patient has bigger BMI than the one in the table, the clinician should prepare longer needle than the usual spinal needle.

Cervical Spondylopathy and Lumbar Intervertebral Disc Herniation Coexist in Free Radical Metabolism and Focus Separation in the Body

Lumbar disc herniation is a common lumbar disease in clinics, which is related to improper use of lumbar vertebrae and osteoporosis. Surgical removal of nucleus pulposus and maintenance of lumbar structural stability are important for the treatment of lumbar disc herniation. At present, in clinical percutaneous intervertebral foramen endoscopic surgery for lumbar disc herniation, interlaminar and intervertebral foramen approaches can be selected. Different approaches have different degrees of difficulty in the treatment of lumbar disc herniation, and the clinical effects that may be obtained are different. In this study, we observed the influencing factors of plasma nitric oxide (NO) and free radical metabolism in patients with lumbar disc herniation and the correlation between the effects of focus separation. The organic combination of local and total illness differentiation and dialectics, conventional acupuncture, and electrical stimulation was highlighted in this study, which linked local acupoints squeezed by nerve roots with distant acupoints along meridians. The use of authoritative quantitative standards and a multifactor assessment of the disease can accurately represent the disease's severity. The patient's condition changes in each period may be expressed more accurately, thoroughly, and objectively through the rise or reduction of the score, making self-evaluation easier for the patient. Electroacupuncture at point may be one of the most important strategies to minimize free radical damage, based on changes in plasma levels.

[Correlation of the epidural space measured intraoperatively and estimated by MRI or US: an observational study]

BACKGROUND AND OBJECTIVES

To assess the agreement between the epidural depth measured from the surgical site with the epidural depths estimated with magnetic resonance imaging (MRI) and ultrasound scanning.

METHODS

Fifty patients of either sex, scheduled for L4-5 lumbar disc surgery under general anesthesia were enrolled in this prospective observational study, and the results of 49 patients were analyzed. The actual epidural depth was measured from the surgical site with a sterile surgical scale. The MRI-derived epidural depth was measured from the MRI scan. The ultrasound estimated epidural depth was measured from the ultrasound image obtained just before surgery.

RESULTS

The mean epidural depth measured from the surgical site was 53.80 ± 7.67mm, the mean MRI-derived epidural depth was 54.06 ± 7.36mm, and the ultrasound-estimated epidural depth was 53.77 ± 7.94mm. The correlation between the epidural depth measured from the surgical site and MRI-derived epidural depth was 0.989 (r² = 0.979, p < 0.001), and the corresponding correlation with the ultrasound-estimated epidural depth was 0.990 (r² = 0.980, p < 0.001).

CONCLUSIONS

Both ultrasound-estimated epidural depth and MRI-derived epidural depth have a strong correlation with the epidural depth measured from the surgical site. Preprocedural MRI-derived estimates of epidural depth are slightly deeper than the epidural depth measured from the surgical site, and the ultrasound estimated epidural depths are somewhat shallower. Although both radiologic imaging techniques provided reliable preprocedural estimates of the actual epidural depth, the loss of resistance technique cannot be discarded while inserting epidural needles.

Correlation of the epidural space measured intraoperatively and estimated by MRI or US: an observational study

Background and objectives

To assess the agreement between the epidural depth measured from the surgical site with the epidural depths estimated with magnetic resonance imaging (MRI) and ultrasound scanning.

Methods

Fifty patients of either sex, scheduled for L4‒5 lumbar disc surgery under general anesthesia were enrolled in this prospective observational study, and the results of 49 patients were analyzed. The actual epidural depth was measured from the surgical site with a sterile surgical scale. The MRI-derived epidural depth was measured from the MRI scan. The ultrasound estimated epidural depth was measured from the ultrasound image obtained just before surgery.

Results

The mean epidural depth measured from the surgical site was 53.80 ± 7.67 mm, the mean MRI-derived epidural depth was 54.06 ± 7.36 mm, and the ultrasound-estimated epidural depth was 53.77 ± 7.94 mm. The correlation between the epidural depth measured from the surgical site and MRI-derived epidural depth was 0.989 (r² = 0.979, p < 0.001), and the corresponding correlation with the ultrasound-estimated epidural depth was 0.990 (r² = 0.980, p < 0.001).

Conclusions

Both ultrasound-estimated epidural depth and MRI-derived epidural depth have a strong correlation with the epidural depth measured from the surgical site. Preprocedural MRI-derived estimates of epidural depth are slightly deeper than the epidural depth measured from the surgical site, and the ultrasound estimated epidural depths are somewhat shallower. Although both radiologic imaging techniques provided reliable preprocedural estimates of the actual epidural depth, the loss of resistance technique cannot be discarded while inserting epidural needles.