Deep Spinal Infection after Outpatient Epidural Injections for Pain: A Retrospective Sample Cohort Study Using a Claims Database in South Korea.

BACKGROUND: Deep spinal infection is a devastating complication after epidural injection. This study aimed to investigate the incidence of deep spinal infection primarily after outpatient single-shot epidural injection for pain. Secondarily, this study assessed the national trends of the procedure and risk factors for said infection. METHODS: Using South Korea's National Health Insurance Service sample cohort database, the 10-yr national trend of single-shot epidural injections for pain and the incidence rate of deep spinal infection after the procedure with its risk factors were determined. New-onset deep spinal infections were defined as those occurring within 90 days of the most recent outpatient single-shot epidural injection for pain, needing hospitalization for at least 1 night, and receiving at least a 4-week course of antibiotics. RESULTS: The number of outpatient single-shot epidural injections per 1,000 persons in pain practice doubled from 40.8 in 2006 to 84.4 in 2015 in South Korea. Among the 501,509 injections performed between 2007 and 2015, 52 cases of deep spinal infections were detected within 90 days postprocedurally (0.01% per injection). In multivariable analysis, age of 65 yr or more (odds ratio, 2.91; 95% CI, 1.62 to 5.5; P = 0.001), living in a rural area (odds ratio, 2.85; 95% CI, 1.57 to 5.0; P < 0.001), complicated diabetes (odds ratio, 3.18; 95% CI, 1.30 to 6.7; P = 0.005), multiple epidural injections (three times or more) within the previous 90 days (odds ratio, 2.34; 95% CI, 1.22 to 4.2; P = 0.007), and recent use of immunosuppressants (odds ratio, 2.90; 95% CI, 1.00 to 6.7; P = 0.025) were significant risk factors of the infection postprocedurally. CONCLUSIONS: The incidence of deep spinal infection after outpatient single-shot epidural injections for pain is very rare within 90 days of the procedure (0.01%). The data identify high-risk patients and procedure characteristics that may inform healthcare provider decision-making.

Effects of a single-bolus bupivacaine injection into the coccygeal spinal canal of rabbits.

It has been reported that drugs intended for epidural administration through the lumbosacral junction are accidentally administered into the subarachnoid space frequently in rabbits. Therefore, we evaluated the epidural single-bolus injection technique for the administration of bupivacaine into the coccygeal spinal canal of rabbits. After epidural distribution was confirmed by the injection of iohexol into the coccygeal spinal canal, 0.3 ml/kg 0.5% bupivacaine or 0.3 ml/kg normal saline was injected via the same needle. After the first attempt of iohexol injection, although the contrast was found in the epidural space in all rabbits, the additional contrast was also found in blood vessel in 3 rabbits and in muscular layer in 1 rabbit. Subarachnoid distribution was not observed in any of the rabbits. The time taken to regain normal anal reflex, movement of the hind limbs during walking, conscious proprioception of the hind limbs, and pain sensation of the tail and left hind limb, following coccygeal spinal canal injection, were significantly longer in the bupivacaine group than in the normal saline group. These findings indicated that coccygeal epidural injection of bupivacaine in rabbits may provide anesthesia for the hind limbs, perineum, and tail, but inadvertent vascular entry of the epidural drug may occur.

The Influence of Local Anesthesia Depth on Procedural Pain During Fluoroscopically Guided Lumbar Transforaminal Epidural Injections: A Randomized Clinical Trial.

OBJECTIVES: The aim of the study was to evaluate the influence of the depth of local anesthesia application on procedural pain during lumbar transforaminal epidural steroid injection. DESIGN: Sixty-eight patients were enrolled who were scheduled for single-level, unilateral fluoroscopically guided lumbar transforaminal epidural steroid injection. Patients were randomly allocated to receive either subcutaneous local anesthesia (group S) or deep local anesthesia (group D) for transforaminal epidural steroid injection. The data related to pain and technical performance during the procedure was compared. In addition, the incidence of injection site soreness was assessed 2 wks after transforaminal epidural steroid injection. RESULTS: Sixty-seven patients completed all assessments (group S, n = 33; group D, n = 34). There was no significant difference in procedural pain and discomfort level between the groups (P = 0.151, P = 0.183, respectively). Patients in group D showed lower behavioral pain scores (P = 0.017). There was no significant difference in the numbers of needle manipulations, fluoroscopy time, and radiation dose during the procedure between the groups. Two patients in group S and three in group D complained of injection site soreness after transforaminal epidural steroid injection for a few days, but there was no significant difference in its incidence (P = 0.667). CONCLUSIONS: Deep local anesthesia to reduce procedural pain during transforaminal epidural steroid injection seems to have no significant clinical benefit compared with conventional subcutaneous local anesthesia. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES: Reduce procedural pain by considering clinical factors of the patient during fluoroscopically guided lumbar transforaminal epidural injections.Upon completion of this article, the reader should be able to: (1) Understand the potential impact of procedural pain on the performance of transforaminal epidural steroid injections; (2) Distinguish cutaneous nociceptive afferents from nociceptive afferents in muscle; and (3) Explain the factors to reduce procedural pain during fluoroscopically guided lumbar transforaminal epidural injections. LEVEL: Advanced ACCREDITATION: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.The Association of Academic Physiatrists designates this Journal-based CME activity for a maximum of 1.0 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.

Intramuscular hematoma with motor weakness after trigger point injection: A case report.

RATIONALE: Although trigger point injection is known as an easy and low-risk procedure, it is contraindicated to patients with hemorrhagic disorders or who regularly take anticoagulants/antiplatelets. However, taking clopidogrel is not a defined contraindication to this low-risk procedure. PATIENT CONCERNS: The chief complaint of a 76-year old woman regularly taking clopidogrel was low back and left buttock pain which prolonged for several years. DIAGNOSES: The patient was diagnosed with L4-5 and L5-S1 spinal stenosis at the orthopedics department and was referred for lumbar spinal epidural steroid injection. INTERVENTION: She was treated with trigger point injection. OUTCOMES: Three hours after the injection, she complained motor weakness and pain in the injection area. A hematoma on left gluteus medium muscle was detected with ultrasonography and ultrasound-guided needle aspiration was accomplished to relieve the symptom. LESSONS: Trigger point injection for patients taking clopidogrel should be done with a caution to prevent such complication.

The Risks of Continuing or Discontinuing Anticoagulants for Patients Undergoing Common Interventional Pain Procedures.

Background: Guidelines have been published that recommend discontinuing anticoagulants in patients undergoing interventional pain procedures. The safety and effectiveness of these guidelines have not been tested. Objectives: The present study was performed to determine if continuing or discontinuing anticoagulants for pain procedures is associated with a detectable risk of complications. Methods: An observational study was conducted in a private practice in which some partners continued anticoagulants while other partners routinely discontinued anticoagulants. Results: No complications attributable to anticoagulants were encountered in 4,766 procedures in which anticoagulants were continued. In 2,296 procedures in which anticoagulants were discontinued according to the guidelines, nine patients suffered serious morbidity, including two deaths. Conclusions: Lumbar transforaminal injections, lumbar medial branch blocks, trigger point injections, and sacroiliac joint blocks appear to be safe in patients who continue anticoagulants. In patients who discontinue anticoagulants, although low (0.2%) the risk of serious complications is not zero, and must be considered when deciding between continuing and discontinuing anticoagulants.

Immediate Adverse Events in Interventional Pain Procedures: A Multi-Institutional Study.

SETTING: Interventional procedures directed toward sources of pain in the axial and appendicular musculoskeletal system are performed with increasing frequency. Despite the presence of evidence-based guidelines for such procedures, there are wide variations in practice. Case reports of serious complications such as spinal cord infarction or infection from spine injections lack appropriate context and create a misleading view of the risks of appropriately performed interventional pain procedures. OBJECTIVE: To evaluate adverse event rate for interventional spine procedures performed at three academic interventional spine practices. METHODS: Quality assurance databases at three academic interventional pain management practices that utilize evidence-based guidelines [1] were interrogated for immediate complications from interventional pain procedures. Review of the electronic medical record verified or refuted the occurrence of a complication. Same-day emergency department transfers or visits were also identified by a records search. RESULTS: Immediate complication data were available for 26,061 consecutive procedures. A radiology practice performed 19,170 epidural steroid (primarily transforaminal), facet, sacroiliac, and trigger point injections (2006-2013). A physiatry practice performed 6,190 spine interventions (2004-2009). A second physiatry practice performed 701 spine procedures (2009-2010). There were no major complications (permanent neurologic deficit or clinically significant bleeding [e.g., epidural hematoma]) with any procedure. Overall complication rate was 1.9% (493/26,061). Vasovagal reactions were the most frequent event (1.1%). Nineteen patients (<0.1%) were transferred to emergency departments for: allergic reactions, chest pain, symptomatic hypertension, and a vasovagal reaction. CONCLUSION: This study demonstrates that interventional pain procedures are safely performed with extremely low immediate adverse event rates when evidence-based guidelines are observed.

Abnormal vaginal bleeding after epidural steroid injection: a paired observation cohort study.

OBJECTIVE: The use of epidural steroid injections has increased dramatically, but knowledge of potential adverse effects is lacking. An association between steroid injection and subsequent abnormal vaginal bleeding has been suspected clinically, but evidence has been limited to anecdotal reports. STUDY DESIGN: Paired observational retrospective cohort study using electronic medical records from a large integrated health care system. Participants were all nonhysterectomized women who underwent epidural steroid injections in 2011. For each steroid injection, encounters for abnormal vaginal bleeding during the 60 days preceding and 60 days after the injection were compared as paired observations. For women found to have bleeding, medical records review was performed to examine menopausal status and bleeding evaluation outcomes. RESULTS: Among 8166 epidural steroid injection procedures performed on 6926 nonhysterectomized women, 201 (2.5%) procedures were followed by at least 1 outpatient visit for abnormal vaginal bleeding. Women were 2.8 times more likely to present with abnormal vaginal bleeding during the postinjection period compared with the preinjection period (P < .0001). Of the 197 women with postinjection bleeding, 137 (70%) were premenopausal and 60 (30%) were postmenopausal. Postinjection bleeding prompted endometrial biopsy evaluation in 103 (52%) cases, with benign findings for 100% of premenopausal women (59/59) and 95% of postmenopausal women (42/44). CONCLUSION: Epidural steroid injections are associated with subsequent abnormal vaginal bleeding for both premenopausal and postmenopausal women. Women undergoing epidural steroid injection should be advised of abnormal bleeding as a potential adverse effect and providers should be aware of this association when evaluating abnormal bleeding.

Cervical epidural steroid injections for the treatment of cervical spinal (neck) pain.

Cervical epidural steroid injections (CESI) are an accepted treatment for neck pain with a radicular component, and may be accomplished by using either transforaminal (CTFESI) or interlaminar (CILESI) approaches. CESIs are routinely performed using real-time fluoroscopic-guidance in conjunction with the injection of water soluble, iodine-based contrast media to enhance visualization of intravascular injections. Digital subtraction angiography (DSA) imaging is an adjuvant to fluoroscopic methods for visualizing blood vessels while performing spinal injections. However, as with any neuraxial procedure, various complications associated with CESIs have been reported. Complications are directly associated with the technical procedures of CESIs. Particulate steroids may have a prolonged duration of action but non-particulate steroids are safer for CESIs. Blunt-beveled needles are less likely than sharp-beveled needles to penetrate blood vessels to cause bleeding complications during CTFESI procedures. Small doses of local anesthetics appear to be safe and assist in identifying intravascular injections previously overlooked by conventional techniques.

Low bone mineral density, but not epidural steroid injection, is associated with fracture in postmenopausal women with low back pain.

BACKGROUND: Therapy with glucocorticoids often results in bone loss and glucocorticoid-induced osteoporosis. However, the relationship between epidural steroid injection (ESI), bone mineral density (BMD), and vertebral fracture remains to be determined. OBJECTIVE: To establish a relationship between ESI, BMD, and vertebral fracture in postmenopausal women with low back pain. STUDY DESIGN: This study was a retrospective, nonblinded, cross-sectional clinical study. SETTING: University-based pain management center. METHODS: We reviewed the medical records of postmenopausal women with low back pain who were treated with ESI. A total of 352 postmenopausal women were divided into 2 groups. Group 1 consisted of patients without fracture and Group 2 consisted of those with fractures. The results of BMD measurements, as well as any fragility fractures, the anatomical site involved, and the treatment administered, were also recorded. BMD was measured in the lumbar spine, femoral neck, and total femur after the treatment. RESULTS: Of the 352 patients, 218 (62%) had no fractures while 134 (38%) sustained a fracture. The age was significantly higher among patients who sustained fractures, and BMD at the lumbar spine, total femur, and femoral neck regions was significantly lower among patients who sustained fractures. In each region, the prevalence of osteoporosis was significantly higher in patients with fracture than in patients without fracture (all P < 0.05). Age, height, and weight were associated with low BMD. However, our study showed no consistent correlation between BMD and the mean number of ESIs, mean total dose of glucocorticoids, or mean duration of ESIs. LIMITATIONS: First, this study is limited by the fact that it was retrospective. Second, the number of cases receiving very frequent, high-dose glucocorticoid injections was very small. CONCLUSIONS: Older age and lower BMD were associated with osteoporotic fracture in postmenopausal women treated for low back pain with ESI. The ESIs were not associated with low BMD or fracture.

Corticosteroid induced psychosis in the pain management setting.

BACKGROUND: Synthetic corticosteroids are commonly utilized in interventional pain management procedures. These substances have potential side-effects including psychological adverse events. OBJECTIVE: We describe a case of substance-induced psychotic disorder resulting from corticosteroids administration. DESIGN: Case Report. METHODS: We describe a 67-year-old male that, six months prior to being consulted at our center, received a cervical epidural, 4 level medial branch blocks, 4 trigger point injections and a tendon injection in the shoulder all including corticosteroids all in one treatment session. RESULTS: Approximately 7 days following the multiple injections, the patient developed psychotic episodes including racing thoughts, anger, agitation, pressured hyperverbal speech and paranoia. The symptoms spontaneously resolved in approximately 7-10 days. DISCUSSION: Although well known as a potential complication, corticosteroid induced psychosis secondary to interventional pain procedures have never been reported. We further discuss this potential side effect of utilizing corticosteroids and emphasize the need for guidelines regarding steroid utilization.

Acute intracranial subdural hematoma after epidural steroid injection: a case report.

OBJECTIVE: Conservative treatment of lumbar radiculopathy includes bed rest, oral medications, physical therapy, spinal manipulation, mobilization, and epidural steroid injections. Intracranial subdural hematoma after accidental dural puncture is a rare and life-threatening complication of epidural steroid injections. In this report, we present a case of subacute intracranial subdural hematoma that developed after epidural steroid injection. CLINICAL FEATURES: A 40-year-old man was admitted to our clinic with severe persistent headache and vomiting for 2 days after epidural steroid injection for right leg pain. INTERVENTION AND OUTCOME: The patient was hospitalized for epidural steroid injection for right leg pain in our pain clinic and was discharged the same day. Twenty-four hours later, he started having a headache. Despite the use of oral analgesics, his headache worsened, and he began to vomit particularly in the upright position. Magnetic resonance imaging of the brain displayed a right frontal subdural hematoma. The headache was relieved after strict bed rest, intravenous hydration, and analgesics. The patient was discharged with full recovery after 1 week. CONCLUSION: Intracranial subdural hematoma after accidental dural puncture during epidural steroid injection is a rare complication. Persistent headache should be evaluated carefully for possible intracranial hematomas.

Influence of needle position on lumbar segmental nerve root block selectivity.

BACKGROUND AND OBJECTIVES: In patients with chronic low back pain radiating to the leg, segmental nerve root blocks (SNRBs) are performed to predict surgical outcome and identify the putative symptomatic spinal nerve. Epidural spread may lead to false interpretation, affecting clinical decision making. Systematic fluoroscopic analysis of epidural local anesthetic spread and its relationship to needle tip location has not been published to date. Study aims include assessment of epidural local anesthetic spread and its relationship to needle position during fluoroscopy-assisted blocks. METHODS: Patients scheduled for L4, L5, and S1 blocks were included in this prospective observational study. Under fluoroscopy and electrostimulation, they received 0.5 mL of a mixture containing lidocaine 5 mg and iohexol 75 mg. X-rays with needle tip and contrast were scored for no epidural spread (grade 0), local spread epidurally (grade 1), or to adjacent nerve roots (grade 2). RESULTS: Sixty-five patients were analyzed for epidural spread, 62 for needle position. Grade 1 epidural spread occurred in 47% of L4 and 28% of L5 blocks and grade 2 spread in 3 blocks (5%; L5 n = 1, S1 n = 2). For lumbar blocks, the needle was most frequently found in the lateral upper half of the intervertebral foramen. Epidural spread occurred more frequently with medial needle positions (P = .06). CONCLUSION: The findings suggest (P = .06) that the risk of grade 1 and 2 lumbar epidural spread, which results in decreased SNRB selectivity, is greater with medial needle positions in the intervertebral foramen. The variability in anatomic position of the dorsal root ganglion necessitates electrostimulation to guide SNRB in addition to fluoroscopy.

Cauda equina syndrome after epidural steroid injection: a case report.

OBJECTIVE: Conventional treatment methods of lumbusacral radiculopathy are physical therapy, epidural steroid injections, oral medications, and spinal manipulative therapy. Cauda equina syndrome is a rare complication of epidural anesthesia. The following case is a report of cauda equina syndrome possibly caused by epidural injection of triamcinolone and bupivacaine. CLINICAL FEATURES: A 50-year-old woman with low back and right leg pain was scheduled for epidural steroid injection. INTERVENTION AND OUTCOME: An 18-gauge Touhy needle was inserted until loss of resistance occurred at the L4-5 level. Spread of the contrast medium within the epidural space was determined by radiographic imaging. After verifying the epidural space, bupivacaine and triamcinolone diacetate were injected. After the injection, there was a reduction in radicular symptoms. Three hours later, she complained of perineal numbness and lower extremity weakness. The neurologic evaluation revealed loss of sensation in the saddle area and medial aspect of her right leg. There was a decrease in the perception of pinprick test. Deep-tendon reflexes were decreased especially in the right leg. She was unable to urinate. The patient's symptoms improved slightly over the next few hours. She had a gradual return of motor function and ability of feeling Foley catheter. All of the symptoms were completely resolved over the next 8 hours. CONCLUSION: Complications associated with epidural steroid injections are rare. Clinical examination and continued vigilance for neurologic deterioration after epidural steroid injections is important.