Location of Radicular Spinal Arteries in the Lumbar Spine from Analysis of CT Angiograms of the Abdomen and Pelvis.

OBJECTIVE: Reports of catastrophic neurologic injuries following lumbar transforaminal epidural steroid injections are rare but serious potential complications. The traditional method of performing lumbar transforaminal epidural steroid injections is in the "safe triangle" to avoid contact to the spinal nerve. Some authors advocate an alternative approach by placing the needle inferiorly in a region referred to as "Kambin's triangle" to avoid incurring arteries. This study aimed to determine the location of arteries within the L1-L4 intervertebral foramen in vivo, specifically if they lie within or in close proximity to the "safe triangle" or Kambin's triangle using CT angiograms of the abdomen and pelvis. STUDY DESIGN: The authors retrospectively evaluated the location in vivo of arterial vessels in the intervertebral foramen from L1 to L4 in patients who underwent abdominopelvic CT angiograms for aortic vascular disease. The data were reanalyzed to confirm inter-rater reliability. RESULTS: Arteries were found in both the safe triangle and Kambin's triangle at a statistically significant rate (P < 0.05). CONCLUSIONS: In this group of patients, an artery was found in either the safe triangle or in Kambin's triangle frequently, suggesting the location of these arteries can be quite variable. Physicians performing these procedures should use universal precautions to avoid inadvertent injection into the lumbar spinal arteries and minimize potential complications regardless of the approach.

The Fluoroscopic-Guided Cervical Transarticular Epidural Steroid Injection.

ABSTRACT: The epidural space is commonly accessed via an interlaminar or transforaminal approach to administer corticosteroids for radicular pain. An alternative is a transarticular approach, which may be considered when conventional access to the epidural space is either not desired or contraindicated. This approach has been described in the cervical spine using computed tomography guidance but not fluoroscopic guidance. We describe a cervical transarticular approach to the epidural space under fluoroscopy and review the computed tomography-guided literature. The risks of transarticular epidural injections are likely low given that when performed prudently, they avoid direct contact with the vertebral artery, spinal medullary arteries, venous plexus, spinal cord, and nerve roots.

Multiple Sterile Withdrawals from Iohexol Bottles Does Not Increase Contamination Risk.

BACKGROUND: There is a global shortage of iohexol contrast media, commonly used in epidural injections, as a result of lockdown and decreased production due to COVID-19. Iohexol bottles are designated for single use, which, depending on the vials available, often leads to wasting up to 95% of this limited resource. However, avoiding multiple withdrawals may be unnecessary if withdrawing multiple times using sterile technique does not increase the risk for contamination. OBJECTIVES: The purpose of our study is to determine whether multiple withdrawals from iohexol injection bottles using a sterile technique poses a greater risk of introducing contaminants than a single withdrawal. Furthermore, we wish to determine the extent to which bacteria can survive and grow in the contrast media. STUDY DESIGN: Experimental. SETTING: Outpatient fluoroscopic suite and laboratory. METHODS: Twenty-one 100 mL 300 mg(iodine)/mL iohexol injection bottles, after one clinical use, were tested after the first and last withdrawals (withdrawal one and withdrawal 9 or 10) for bacterial and fungal specimens using culture media and 3M™ Petrifilms™. To determine the ability of methicillin-susceptible Staphylococcus aureus (MSSA) to survive or grow in the media, MSSA was added to different concentrations (0, 25, 50, 75, and 100%) of iohexol contrast media. RESULTS: There was no growth observed in cultures or on Petrifilms among the first and last draws of any of the samples. When bacteria were grown in different dilutions of the media, there was a significant, approximately one log decrease in counts from 0% contrast media to 100% contrast media (8.4 x 108 vs 5.6 x 107, P < 0.01). LIMITATIONS: Our study is limited in the number of samples tested and would benefit from additional investigation before consideration of clinical application. CONCLUSIONS: Our results suggest that single-use 300 iohexol bottles may be reusable and that the contrast media is mildly antimicrobial, but not enough to retard contamination. In setting of shortages, contrast media bottles can safely be reused. This is valuable for conserving resources and limiting unnecessary health care-associated costs.

Injectate volumes needed to reach specific landmarks in s1 transforaminal epidural injections.

OBJECTIVES: We identify the contrast volumes needed to reach specific landmarks during S1 transforaminal epidural injections (S1-TFEIs). DESIGN: Prospective, nonrandomized, observational human study. Setting. Academic/private pain management practice. Subjects. Forty-two patients undergoing S1-TFEIs were investigated. Thirty-seven patients were included in this study. Interventions. S1-TFEIs were performed using contrast-enhanced fluoroscopic visualization. MAIN OUTCOME MEASUREMENTS: After confirming appropriate spinal needle position, up to 5 mL of nonionic contrast was slowly injected. Under biplanar fluoroscopic guidance, contrast volumes were recorded as flow reached specific anatomic landmarks: the ipsilateral S1 pedicle, the superior aspect of the L5-S1 disc space, and across the midline of the spinous process. RESULTS: After injecting 2 mL of contrast, 100% of S1-TFEIs spread to the medial aspect of the ipsilateral superior pedicle of S1. After injecting 3.0 mL of contrast, 92% of S1-TFEIs spread to the superior aspect of the L5-S1 intervertebral disc. After injecting 4 mL of contrast, 27% of S1-TFEIs spread beyond the midline of the spinous process, but by only a few millimeters. CONCLUSIONS: This study demonstrates injectate volumes needed to reach specific anatomic landmarks in S1-TFEIs. A volume of 3.0 mL of contrast reaches the superior aspect of the L5-S1 intervertebral disc 92% of the time.

When Clinical Diagnosis Differs From Advanced Imaging: A Case Series of Disc Herniations Causing Radiculopathy and Review of Aberrant Nerve Root Innervation.

ABSTRACT: Radiculopathy is diagnosed using a combination of history, physical examination, and imaging. Unfortunately, well-established dermatomal and myotomal maps are an oversimplification of the convoluted nature of spinal sensory and motor innervation. When clinical presentation and imaging seemingly contradict one another, it is important to consider variant innervation patterns. This article presents three patients with objective dermatomal and/or myotomal deficits due to disc herniations whose clinical presentations are "textbook" for nerve root pathology that is adjacent to the nerve root that is actually compromised. In addition, the literature is reviewed to discuss the history of dermatomal and myotomal maps, the effectiveness of a clinician's ability to determine the precise pathologic disc and nerve root level in patients presenting with radiculopathy, and anatomical explanations as to why inconsistencies such as those seen in the patients in these cases exist.

The PROMIS Upper Extremity Computer Adaptive Test Correlates With Previously Validated Metrics in Patients With Carpal Tunnel Syndrome.

Background: The Patient-Reported Outcomes Measurement Information System Upper Extremity (PROMIS UE) computer adaptive test was developed to improve precision and reduce question burden. We hypothesized that in patients with carpal tunnel syndrome (CTS): (1) PROMIS UE would correlate with established patient-reported outcome measures (PROs); (2) the time and number of questions required would be lower than current metrics; (3) there would be no floor or ceiling effects; and (4) PROMIS UE would not correlate with disease severity. Methods: Patients undergoing electrodiagnostic evaluation found to have a primary diagnosis of unilateral CTS prospectively completed PROMIS UE, Quick Disabilities of the Arm, Shoulder and Hand (qDASH), and Boston Carpal Tunnel Syndrome Questionnaire (BCTQ). Electrophysiologic and clinical severity was recorded. The relationships among PROs were described with Spearman coefficients. A floor or ceiling effect was confirmed if >15% of patients achieved the lowest or highest possible score, respectively. Results: Fifty-one patients (average, 53.9 years) were enrolled. An excellent correlation was identified between PROMIS UE and qDASH (R = -0.76, P < .001). There was a good correlation between PROMIS UE and BCTQ (R = -0.58, P < 0.001). The PROMIS UE required less time and fewer questions than qDASH and BCTQ (P = .02 and P < .001). There were no floor or ceiling effects. Neither neurophysiologic nor clinical severity correlated with PROMIS UE (R = 0.24, P > .05 and R = -0.18, P > .05). Conclusions: The PROMIS UE has an excellent correlation with qDASH and a good correlation with BCTQ in patients with CTS. Furthermore, PROMIS UE required less time and fewer questions than established PROs. Used as a single PRO, PROMIS UE represents a practical alternative to current metrics in patients with CTS.

Caudal Epidural Steroid Injections in the Setting of Remaining on Antithrombotics: A Retrospective Study.

BACKGROUND: The American Society of Regional Anesthesia currently recommends ceasing antithrombotic medications for all spinal epidural steroid injections, however there is a paucity of data on the true risk of spinal epidurals via various approaches versus the risk of cessation of an agent as it relates to the underlying medical condition. OBJECTIVE: This study evaluated the complication rate of caudal epidural steroid injections in patients who remain on antithrombotic medications. STUDY DESIGN: Retrospective chart review. SETTING: Physiatric Spine Clinic in Orthopedic Specialty Office and Surgical Center. METHODS: A retrospective chart review was performed identifying patients (n = 335) who received a caudal epidural steroid injection (n = 673) from June 2015 through April 2020. Patients were included if they had received the injection while taking an antithrombotic medication. Patients were excluded if they were not taking an antithrombotic. The patient's age, indication for the injection including magnetic resonance imaging or computed tomography findings, antithrombotic medication, the medical condition requiring an antithrombotic, and any complications following the injection were collected via chart review. RESULTS: Of the 443 injections included in the study, 51 encounters were lost to follow-up. Of the other 392 injections, there were no reported complications, regardless of the patient's imaging findings, age, the antithrombotic medication used, or the underlying medical condition for which an antithrombotic medication was indicated. LIMITATIONS: This is a retrospective study. Therefore, a prospective study may have yielded fewer encounters lost to follow-up. Patients were not contacted directly after the procedure and chart reviews were utilized to evaluate for complications, which was limited to a patient's reporting of perceived complications without any imaging. CONCLUSIONS: We conclude that caudal epidural steroid injections can be performed safely in patients while taking antithrombotic medications. Catastrophic events have been observed in patients who have discontinued antithrombotic agents preceding procedures. Thus, discontinuing antithrombotic medications may pose a greater risk than benefit for patients on an antithrombotic medication who have painful lumbar radiculopathy.

Paralysis After Lumbar Interlaminar Epidural Steroid Injection in the Absence of Hematoma: A Case of Congestive Myelopathy Due to Spinal Dural Arteriovenous Fistula and a Review of the Literature.

Paraplegia after interlaminar epidural steroid injection is a rare event and has typically been described after epidural hematoma or direct spinal cord injury. We present a case of an 87-yr-old man who experienced transient lower limb weakness after a lumbar interlaminar epidural steroid injection due to an alternative cause, congestive myelopathy related to an underlying vascular malformation, namely, a spinal dural arteriovenous fistula. This is a poorly recognized and potentially treatable cause of progressive myelopathy. We present this case and review the literature on paraplegia after epidural steroid injection due to spinal dural arteriovenous fistula. Notably, this case of paralysis occurred in association with the lowest volume of epidural injectate reported in the literature to date (4 ml); importantly, this volume is consistent with the current clinical practice guideline standards for the safe performance of interlaminar epidural steroid injections. Physicians should be aware of this potential complication of epidural steroid injection and remain vigilant for the possibility after a procedure, even when performed according to current practice standards.

Septic Sacroiliitis in a 53-Year-Old Adult: A Case Report.

A 53-year-old woman with no significant medical history presented with 10/10 right buttock pain that radiated to the right groin. With no reported recent injury, the absence of fever, and no identifiable risk factors, an infectious etiology, including septic sacroiliitis (SSI), is at the end spectrum of the differential. SSI is a rare condition with nonspecific findings that can lead to major complications, including death. To our knowledge, there are only 4 recent major literature reviews on SSI, with most cases reported to have at least 1 risk factor or clinical sign indicating the possibility of an infectious etiology. The patient reported in this case had no identifiable risk factors; therefore, high clinical suspicion is needed to prevent debilitating consequences from prolonged infection. LEVEL OF EVIDENCE: V.

Contrast flow selectivity during transforaminal lumbosacral epidural steroid injections.

BACKGROUND: Lumbosacral transforaminal epidural steroid injections (LS-TFESIs) are an accepted procedure used in the comprehensive, conservative care for lumbar disc pathology and/or spinal stenosis induced low back pain with a radicular component. Historically, the terminology used to describe the transforaminal technique of instilling medications into the epidural space and/or exiting structures has varied. These procedures have also been referred to as either diagnostic or therapeutic selective nerve root blocks (SNRBs). Although this procedure is typically used to "selectively" treat isolated pathology, the "SNRB" terminology suggests that one can selectively diagnose or treat a specific nerve root as a pain generator by anesthetizing or blocking it. It has been recently demonstrated that L4 and L5 SNRBs are often non-"selective" by investigating the extent of epidural contrast flow patterns after injecting 1.0 mL of contrast. Our study attempts to identify the minimum injectate volume at which LS-TFESIs may still be considered "selective" with no injectate extending to either the adjacent (superior and/or inferior) levels or to the contralateral side. OBJECTIVE: Quantitatively evaluate contrast flow level selectivity noted during fluoroscopically guided lumbosacral transforaminal epidural steroid injections (LS-TFESIs). STUDY DESIGN: Prospective, nonrandomized, observational human study. METHODS: Thirty patients (female = 10, male = 20) undergoing LS-TFESIs were investigated. After confirming appropriate spinal needle position with biplanar imaging, 4.0 mL of nonionic contrast was slowly injected. Fluoroscopic images were recorded at 0.5 mL increments. These biplanar contrast flow images were evaluated to determine which 0.5 mL volume increment was no longer specific for the injected level. In particular, we documented when contrast extended either to a superior or inferior spinal segment or crossed the midline spine to the contralateral side. RESULTS: After injecting 0.5 mL of contrast, 30% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. After injecting 1.0 mL of contrast, 67% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. After injecting 1.5 mL of contrast, 87% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. After injecting 2.5 mL of contrast, 90% of LS-TFESIs performed in this study were no longer "selective" for the specified root level. CONCLUSIONS: Diagnostic LS-TFESI or SNRB blocks limiting injectate to a single, ipsilateral segmental level cannot reliably be considered diagnostically selective with volumes exceeding 0.5mL. Injectate volumes greater than 0.5mL are consistently non-selective and cannot be used reliably for diagnostic block procedures in the epidural space.

Successful Repeat Sacroplasty in a Patient With a Recurrent Sacral Insufficiency Fracture: A Case Presentation.

The standard of care for treatment of sacral insufficiency fracture (SIF) remains conservative management with limited weight-bearing and analgesics, as most fractures heal within 12 weeks. For those who fail to respond to conservative therapy, are immobile, or cannot tolerate the pain despite analgesic therapy, as well as those who do not improve with time, rest, or activity modification, minimally invasive surgery with percutaneous transverse screw fixation across the fracture is effective. However, a less invasive procedure, percutaneous sacroplasty, may be an option for potential rapid pain reduction. This is a novel report of repeat sacroplasty in a patient with a recurrent SIF to the same anatomical area as a previously treated SIF. To our knowledge, this is the first report of such an occurrence. LEVEL OF EVIDENCE: Not applicable.

Case report: a case review of Lambert-Eaton myasthenic syndrome and low back pain.

The following is a case report which reviews the essential aspects of Lambert-Eaton myasthenic syndrome (LEMS) in a patient with long standing back pain and gait dysfunction. The patient was referred to our electrodiagnostics laboratory for a 9-month history of low back pain and difficulty walking following a charity breast cancer walk. A workup including magnetic resonance imaging of the brain, entire spine, and EMG/NCS at another institution were reportedly normal. A detailed history revealed symptoms of proximal weakness and autonomic dysfunction. Physical findings were consistent with proximal weakness, a bilateral gluteus medius gait, and diffusely absent reflexes obtainable in the biceps after 3 s of contraction. Electrical testing revealed an initial low compound muscle action potential amplitude in the deep peroneal nerve recording from the extensor digitorum brevis. Repetitive stimulation at 2 Hz revealed a decremental response of 42% from the 1st response to the 4th response. Following 3 s of exercise, the amplitude increased by 300%. After 30 s of exercise followed by 1 min of rest, there was a return of the decremental response. The history, physical examination, and electrical findings were illustrative of a presynaptic neuromuscular junction disorder, specifically LEMS.

Injectate volumes needed to reach specific landmarks in lumbar transforaminal epidural injections.

OBJECTIVES: To identify the volumes of contrast material needed to reach specific landmarks during lumbar transforaminal epidural injections (L-TFEIs). DESIGN: Prospective, nonrandomized, observational human study. SETTING: Academic/private pain management practice. PATIENTS: Sixty-nine patients undergoing L-TFEIs were investigated. Sixty patients were included in this study. INTERVENTIONS: L-TFEIs were performed with the use of contrast-enhanced fluoroscopic visualization. MAIN OUTCOME MEASUREMENTS: After the appropriate spinal needle position was confirmed, up to 5.0 mL of nonionic contrast material was slowly injected. Under biplanar fluoroscopic guidance, contrast volumes were recorded as flow reached specific anatomic landmarks: ipsilateral neural foramen, ipsilateral disks superior and inferior to the injected level, and across the midline of the spinous process. RESULTS: After 1.1 mL of contrast was injected, 100% of L-TFEIs spread to the medial aspect of the superior pedicle (PED) of the corresponding level of injection. After 2.8 mL of contrast was injected, 95% of L-TFEIs spread to the superior aspect of the superior intervertebral disk (IVD) of the corresponding level of injection. After 3.6 mL of contrast was injected, 95% of L-TFEIs spread to the inferior aspect of the inferior IVD of the corresponding level of injection. After 3 mL of contrast was injected, 88% of L-TFEIs spread to cover both the superior and inferior IVDs of the corresponding level of injection. After 4 mL of contrast was injected, 93% of L-TFEIs spread to cover both the superior and inferior IVDs of the corresponding injection. After 4 ml of contrast was injected, 55% of L-TFEIs spread beyond the midline of the spinous process, but barely. CONCLUSION: This study demonstrates injectate volumes needed to reach specific anatomic landmarks in L-TFEIs. A volume of 4.0 mL of injectate reaches both the superior aspect of the superior IVD and the inferior aspect of the inferior IVD 93% of the time.