Image Guidance Technologies for Interventional Pain Procedures: Ultrasound,Fluoroscopy, and CT

Chronic pain is a common medical condition. Patients who suffer uncontrolled chronic pain may require interventions including spinal injections and various nerve blocks. Interventional procedures have evolved and improved over time since epidural injection was first introduced for low back pain and sciatica in 1901. One of the major contributors in the improvement of these interventions is the advancement of imaging guidance technologies. The utilization of image guidance has dramatically improved the accuracy and safety of these interventions. The first image guidance technology adopted by pain specialists was fluoroscopy. This was followed by CT and ultrasound. Fluoroscopy can be used to visualize bony structures of the spine. It is still the most commonly used guidance technology in spinal injections. In the recent years, ultrasound guidance has been increasingly adopted by interventionists to perform various injections. Because its ability to visualize soft tissue, vessels, and nerves, this guidance technology appears to be a better option than fluoroscopy for interventions including SGB and celiac plexus blocks, when visualization of the vessels may prevent intravascular injection. The current evidence indicates the efficacies of these interventions are similar between ultrasound guidance and fluoroscopy guidance for SGB and celiac plexus blocks. For facet injections and interlaminar epidural steroid injections, it is important to visualize bony structures in order to perform these procedures accurately and safely. It is worth noting that facet joint injections can be done under ultrasound guidance with equivalent efficacy to fluoroscopic guidance. However, obese patients may present challenge for ultrasound guidance due to its poor visualization of deep anatomical structures. Regarding transforaminal epidural steroid injections, there are limited evidence to support that ultrasound guidance technology has equivalent efficacy and less complications comparing to fluoroscopy. However, further studies are required to prove the efficacy of ultrasound-guided transforaminal epidural injections. SI joint is unique due to its multiplanar orientation, irregular joint gap, partial ankylosis, and thick dorsal and interosseous ligament. Therefore, it can be difficult to access the joint space with fluoroscopic guidance and ultrasound guidance. CT scan, with its cross-sectional images, can identify posterior joint gap, is most likely the best guidance technology for this intervention. Intercostal nerves lie in the subcostal grove close to the plural space. Significant risk of pneumothorax is associated with intercostal blocks. Ultrasound can provide visualization of ribs and pleura. Therefore, it may improve the accuracy of the injection and reduce the risk of pneumothorax. At present time, most pain specialists are familiar with fluoroscopic guidance techniques, and fluoroscopic machines are readily available in the pain clinics. In the contrast, CT guidance can only be performed in specially equipped facilities. Ultrasound machine is generally portable and inexpensive in comparison to CT scanner and fluoroscopic machine. As pain specialists continue to improve their patient care, ultrasound and CT guidance will undoubtedly be incorporated more into the pain management practice. This review is based on a paucity of clinical evidence to compare these guidance technologies; clearly, more clinical studies is needed to further elucidate the pro and cons of each guidance method for various pain management interventions.     

Facet joint pain and the role of neural blockade in its management

Chronic spinal pain is a common medical problem with serious financial and social consequences. Among the various structures with potential for producing pain in the spine, facet joints as sources of chronic spinal pain have attracted considerable attention and controversy. Significant progress has been made in precision diagnosis of spinal pain with neural blockade, in the face of less than optimal diagnostic information offered by imaging and neurophysiologic studies. Research into the role of facet joints in spinal pain has shown that cervical facet joints are the cause of chronic neck pain in 54% to 60% of patients, whereas lumbar facet joints cause pain in 15% to 40% of patients with chronic low back pain. Local anesthetic blocks of medial branches have proven to be a reliable diagnostic test; they are target-specific when used appropriately with control blocks, either with two local anesthetics with different durations of action or with the addition of an inactive placebo injection. The literature is replete with reports on uncontrolled studies, case reports, and documentation from a few controlled studies, all of which offer supporting information on the rationale and effectiveness of facet blocks and neurotomy. Facet joint injections and medial branch blocks are considered to be of equal value. Lumbar intra-articular steroid injections have been proven effective to a certain extent, but evidence indicates that cervical intra-articular steroids are ineffective. The role of repeat medial branch blocks is not known. Radiofrequency neurotomy remains the only practical and validated treatment for cervical facet joint pain; however, its role in management of either lumbar or thoracic facet joint pain awaits validation.     

The Prevalence of Facet Joint-Related Chronic Neck Pain in Postsurgical and Nonpostsurgical Patients: A Comparative Evaluation

Background: Facet (zygapophysial) joints may be clinically important sources of chronic cervical spinal pain. Previous studies have demonstrated the value and validity of controlled, comparative local anesthetic blocks in the diagnosis of facet joint pain, and reported an overall prevalence of 36% to 67% facet joint involvement in cervical spinal pain. The reports of lumbar facet joint‐involvement in postsurgery syndrome have been shown to be highly variable with prevalence ranging from 8% to 32%. To date, however, the prevalence of postsurgical facet joint‐related pain in the cervical spine has not been evaluated. In light of this, the present retrospective study was conducted to assess and compare the prevalence of chronic postsurgical facet joint cervical spinal pain to nonsurgical, chronic cervical facet joint pain. Methods: Patients presenting with chronic neck pain were studied. The procedures were performed by a single physician in an interventional pain management ambulatory surgery center. The prevalence of cervical facet joint pain in postsurgical patients was assessed and compared to nonsurgical patients. Results: A total of 251 patients (45 postsurgery vs. 206 nonsurgical patients) with chronic persistent neck pain were evaluated using controlled, comparative local anesthetic blocks in accordance with IASP criteria. The prevalence of the cervical facet joint pain and false‐positive rate of single blocks in postsurgical patients were 36% and 50% compared with 39% and 43% in nonsurgical patients. Conclusions: Cervical facet joints are clinically important pain generators in a significant proportion of patients with chronic persistent neck pain after surgical intervention(s). The prevalence of cervical facet joint pain was similar in both postsurgical and nonsurgical patients. ?     

Ultrasound guided spinal procedures

Ultrasound (US) is an increasingly used imaging technique in interventional pain therapy allowing identification of soft tissues, vessels and nerves, without exposing patients or personnel to radiation. Imaging is performed continuously and the spread of the injected fluid can be visualized in real time. Spinal procedures which may be performed with US imaging are lumbar or cervical facet joint blocks, sacroiliac joint injections, caudal epidural injections and extraforaminal cervical or lumbar nerve root blocks. Limitations are the poor resolution of narrow-gauge needles, the loss of resolution with increasing working depth and possible interference of echoes from overlying structures with the image of the target area.     

Does osteoarthritis of the lumbar spine cause chronic low back pain?

The lumbar spine is a common location for osteoarthritis. The axial skeleton demonstrates the same classic alterations of cartilage loss, joint instability, and osteophytosis characteristic of symptomatic disease in the appendages. Despite these similarities, questions remain regarding the lumbar spine facet joints as a source of chronic back pain. The facet joints undergo a progression of degeneration that may result in pain. The facet joints have sensory input from two spinal levels that makes localization of pain difficult. Radiographic studies describe intervertebral disc abnormalities in asymptomatic individuals that are associated with, but not synonymous for, osteoarthritis. Patients who do not have osteoarthritis of the facet joints on magnetic resonance scan do not have back pain. Single photon emission computed tomography scans of the axial skeleton are able to identify painful facet joints with increased activity that may be helped by local anesthetic injections. Low back pain is responsive to therapies that are effective for osteoarthritis in other locations. Osteoarthritis of the lumbar spine does cause low back pain.     

Ultrasound and chronic pain: Innovative approaches

Ultrasound (US) is an increasingly used imaging technique in interventional pain management. It allows the identification of soft tissues, vessels and nerves, without exposing patients and personnel to radiation. Imaging can be performed continuously and the fluid injected is visualized in a real time fashion. Possible applications are nerve blocks of the cervical and lumbar zygapophysial joints, stellate ganglion block, intercostal and paravertebral nerve blocks, inguinal nerve blocks, occipital nerve blocks, blocks of painful stump neuromas, caudal epidural injections and injections of trigger/tender points. Due to direct nerve visualization, US has a potential application for destructive procedures, such as cryoanalgesia, radiofrequency lesions or chemical neurolysis. Limitations are the poor resolution of narrow-gauge needles, the loss of resolution with increasing working depth and possible interference of echoes from overlying structures with the image of the target area. US opens new perspectives in interventional pain management. However, there is a need for more clinical trials investigating efficacy and safety of US-guided pain procedures. Until these studies are completed, US cannot replace fluoroscopy or computed tomography in most interventional pain procedures and remains the domain of well-trained and experienced physicians. The limited evidence supporting the clinical utility of nerve blocks remains a problem, irrespective of the imaging technique employed.     

Ultrasound and chronic pain

Ultrasound (US) is an increasingly used imaging technique in interventional pain management. It allows the identification of soft tissues, vessels and nerves, without exposing patients and personnel to radiation. Imaging can be performed continuously and the fluid injected is visualized in a real time fashion. Possible applications are nerve blocks of the cervical and lumbar zygapophysial joints, stellate ganglion block, intercostal and paravertebral nerve blocks, inguinal nerve blocks, occipital nerve blocks, blocks of painful stump neuromas, caudal epidural injections and injections of trigger/tender points. Due to direct nerve visualization, US has a potential application for destructive procedures, such as cryoanalgesia, radiofrequency lesions or chemical neurolysis. Limitations are the poor resolution of narrow-gauge needles, the loss of resolution with increasing working depth and possible interference of echoes from overlying structures with the image of the target area. US opens new perspectives in interventional pain management. However, there is a need for more clinical trials investigating efficacy and safety of US-guided pain procedures. Until these studies are completed, US can not replace fluoroscopy or computed tomography in most interventional pain procedures and remains the domain of well-trained and experienced physicians. The limited evidence supporting the clinical utility of nerve blocks remains a problem, irrespective of the imaging technique employed.     

Ultrasound in interventional pain management

Ultrasound (US) is an increasingly used imaging technique in interventional pain management. It allows the identification of soft tissues, vessels and nerves, without exposing patients and personnel to radiation. Imaging can be performed continuously and the fluid injected is visualized in a real time fashion. Possible applications are nerve blocks of the cervical and lumbar zygapophysial joints, stellate ganglion block, intercostal nerve blocks, blocks of painful stump neuromas, caudal epidural injections and injections of trigger/tender points. Due to direct nerve visualization, US has a potential application for destructive procedures, such as cryoanalgesia, radiofrequency lesions or chemical neurolysis. Limitations are the poor resolution of narrow-gauge needles, the lost of resolution with increasing working depth and possible interference of echoes from overlying structures with the image of the target area. US opens new perspectives in interventional pain management. However, there is a need for clinical trials investigating efficacy and safety of US-guided pain procedures. Until these studies are made, US can not replace fluoroscopy or computed tomography in routine clinical practice and remainS domain of well-trained and experienced physicians. The limited evidence supporting the clinical utility of nerve blocks remains a problem, irrespective of the imaging technique employed.     

The provocative lumbar facet joint

Low back pain is the most common pain symptom experienced by American adults and is the second most common reason for primary care physician visits. There are many structures in the lumbar spine that can serve as pain generators and often the etiology of low back pain is multifactorial. However, the facet joint has been increasingly recognized as an important cause of low back pain. Facet joint pain can be diagnosed with local anesthetic blocks of the medial branches or of the facet joints themselves. Subsequent radiofrequency lesioning of the medial branches can provide more long-term pain relief. Despite some of the pitfalls associated with facet joint blocks, they have been shown to be valid, safe, and reliable as a diagnostic tool. Medial branch denervation has shown some promise for the sustained control of lumbar facet joint-mediated pain, but at this time, there is insufficient evidence that it is a wholly efficacious treatment option. Developing a universal algorithm for evaluating facet joint-mediated pain and standard procedural techniques may facilitate the performance of larger outcome studies. This review article provides an overview of the anatomy, pathophysiology, diagnosis, and treatment of facet joint-mediated pain.     

Single needle approach for multiple medial branch blocks: a new technique

BACKGROUND AND OBJECTIVES: Medial branch blocks are an important tool for the diagnosis of facet joint arthropathy. The most commonly used technique involves multiple needle placements, one for each nerve blocked. This multiple needle technique may require a large amount of local anesthetic for anesthetizing the skin, thereby increasing the rate of false-positive blocks. TECHNIQUE: Diagnostic lumbar medial branch blocks are usually performed using multiple needles, one for each branch. The authors describe a different technique using a single needle for all levels. Initially, the needle is directed toward the medial branch located at the level of the affected facet joint in the antero-posterior view. After anesthetizing this nerve with local anesthetic, the same needle is withdrawn to the skin with the tip still in the subcutaneous tissue and repositioned to block the medial branch above, and thereafter below, while continuing to use only the antero-posterior view, thereby using only one entry site. CONCLUSIONS: When performed correctly, the single needle technique provides accuracy similar to the more conventional multiple needle approach during the performance of diagnostic facet joint nerve blocks. Because only one skin entry point is needed, however, this technique may afford several advantages over the multiple needle approach. These may include less patient discomfort, less time required and less radiation exposure since only one C-arm position is used, a smaller volume of local anesthetic, and possibly a lower incidence of false-positive blocks.     

Facet joint injection: a rare form cause of epidural abscess formation

The posterior zygo-apophyseal joints (facet joints) may be a significant source of back pain. Invasive treatment typically consists of injecting the joints with local anaesthetic and steroid or by radiofrequency ablation of the nerve supply to the joint. Facet joint injection is generally considered to be a very safe procedure with few significant side effects reported.Epidural abscess is a rare but potentially very serious occurrence. Most cases occur spontaneously but the condition may complicate epidural anaesthesia, spinal anaesthesia or epidural steroid injection. We report a case in which facet joint injections resulted in epidural abscess formation. To our knowledge this has not previously been reported.     

Utilization of Facet Joint and Sacroiliac Joint Interventions in Medicare Population from 2000 to 2014: Explosive Growth Continues!

Increasing utilization of interventional techniques in managing chronic spinal pain, specifically facet joint interventions and sacroiliac joint injections, is a major concern of healthcare policy makers. We analyzed the patterns of utilization of facet and sacroiliac joint interventions in managing chronic spinal pain. The results showed significant increase of facet joint interventions and sacroiliac joint injections from 2000 to 2014 in Medicare FFS service beneficiaries. Overall, the Medicare population increased 35 %, whereas facet joint and sacroiliac joint interventions increased 313.3 % per 100,000 Medicare population with an annual increase of 10.7 %. While the increases were uniform from 2000 to 2014, there were some decreases noted for facet joint interventions in 2007, 2010, and 2013, whereas for sacroiliac joint injections, the decreases were noted in 2007 and 2013. The increases were for cervical and thoracic facet neurolysis at 911.5 % compared to lumbosacral facet neurolysis of 567.8 %, 362.9 % of cervical and thoracic facet joint blocks, 316.9 % of sacroiliac joints injections, and finally 227.3 % of lumbosacral facet joint blocks.     

Sonographische Darstellung der lumbalen Facettengelenke

Aim

The aim of the study was to investigate whether ultrasound imaging provides a suitable alternative to radiodiagnostics in lumbar facet joint representation prior to facet blockade and radiofrequency denervation in clinical practice.

Materials and methods

A total of 90 lumbar facet joints from 9 corpses (5 segments L1/2 to L5/S1, 2 sides) were examined by 2 investigators using either ultrasonic imaging or gold standard radiology, for segment localization and needle positioning. The deviation of ultrasound-guided needle placement relative to the anatomical target position was measured on X-ray images and all cases were assigned to 5 categories differentiated by 1 mm from category 1 (no deviation, i.e. no correction inevitably) to category 5 (deviation of ≥?4 mm, i.e. not precise).

Results

Ultrasound imaging allowed 82 of the 90 (91 %) investigated lumbar facet joints to be identified in the correct segment. Particularly in all cases for L1/2, L2/3 and L3/4 the joints were identified in the correct segment whereas for L4/5 in 2 cases (11 %) and for L5/S1 in 6 cases (30 %) the wrong segment was targeted. Regarding deviations of ultrasound-guided needle placement the following results were achieved for category 1: n?=?27 (30 %), 2: n?=?45 (50 %), 3: n?=?5 (5.6 %), 4: n?=?9 (10 %), und 5: n?=?4 (4.4 %).

Conclusions

Ultrasound imaging for lumbar facet joint representation is a reliable and simple approach for segment localization and needle positioning, especially above L5/S1. This method can thus be recommended as a suitable alternative to radiology for subsequent accomplishment of facet blockade and radiofrequency denervation in clinical practice.     

Tolerability and Feasibility of X-ray Guided Non-Invasive Ablation of the Medial Branch Nerve with Focused Ultrasound: Preliminary Proof of Concept in a Pre-clinical Model

Four to six million patients a year in the United States suffer from chronic pain caused by facet joint degeneration. Thermal ablation of the affected facet joint's sensory nerve using radiofrequency electrodes is the therapeutic standard of care. High-intensity focused ultrasound (HIFU) is a novel technology enabling image-guided non-invasive thermal ablation of tissue. Six pigs underwent fluoroscopy-guided HIFU of the medial branch nerve and were followed up for 1 wk (two pigs), 1 mo (two pigs) and 3 mo (two pigs). At the end of each follow-up period, the animals were sacrificed, and targeted tissue was excised and evaluated with computed tomography scans as well as by macro- and micropathology. No significant adverse events were recorded during the procedure or follow-up period. All targets were successfully ablated. X-Ray-guided HIFU is a feasible and promising alternative to radiofrequency ablation of the lumbar facet joint sensory nerve.     

12. Pain Originating from the Lumbar Facet Joints

Although the existence of a “facet syndrome” had long been questioned, it is now generally accepted as a clinical entity. Depending on the diagnostic criteria, the zygapophysial joints account for between 5% and 15% of cases of chronic, axial low back pain. Most commonly, facetogenic pain is the result of repetitive stress and/or cumulative low‐level trauma, leading to inflammation and stretching of the joint capsule. The most frequent complaint is axial low back pain with referred pain perceived in the flank, hip, and thigh. No physical examination findings are pathognomonic for diagnosis. The strongest indicator for lumbar facet pain is pain reduction after anesthetic blocks of the rami mediales (medial branches) of the rami dorsales that innervate the facet joints. Because false‐positive and, possibly, false‐negative results may occur, results must be interpreted carefully. In patients with injection‐confirmed zygapophysial joint pain, procedural interventions can be undertaken in the context of a multidisciplinary, multimodal treatment regimen that includes pharmacotherapy, physical therapy and regular exercise, and, if indicated, psychotherapy. Currently, the “gold standard” for treating facetogenic pain is radiofrequency treatment (1 B+). The evidence supporting intra‐articular corticosteroids is limited; hence, this should be reserved for those individuals who do not respond to radiofrequency treatment (2 B±).     

腰椎小关节病的CT检查和表现

目的 对腰椎小关节病ＣＴ表现作出归纳,提高对此病作为腰腿痛的重要病因的认识。方法连续２００例腰腿痛患,主要作了腰椎Ｌ４－５和Ｌ５－Ｓ１的小关节ＣＴ平扫,并运用骨窗和软组织窗对图像进行分析和测量。结果 有１３５例（占６７．５％）患表现为不同节段的腰椎小关节病,ＣＴ表现为：骨赘形成;小关节突增生肥大;关节间隙变窄;关节真空现象以及关节囊的钙化等。腰椎小关节病常伴有其它腰椎疾病。讨论 腰椎小关节病是     

Ultrasound-guided facet joint injections in the middle to lower cervical spine: a CT-controlled sonoanatomic study

OBJECTIVES: The aim of this study was to investigate the efficacy of ultrasound as a guiding tool for simulated cervical facet joint injections in cadavers. METHODS: A total of 40 ultrasound examinations at 5 levels (C6-7 to C2-3) were performed on 4 embalmed cadavers. The zygapophyseal joints were located with ultrasound. First, the transverse processes of C6 and C7 were established and the facet joint of C6-7 was demonstrated. The midpoint of this joint space, defined as the middle of its cranio-caudal extension on its lateral surface, was taken as a reference point. Ipsilateral distances (A, B, C, and D) between this point and each one of the 4 facet joints of the cervical spine up to the facet joints C2-3 were then computed. Subsequently, coronal computed tomography (CT) scans were taken to verify these distances. In a second experiment, a spinal needle was advanced under ultrasound guidance to the zygapophyseal joints from C2-3 to C6-7 on both sides of 1 cadaver. The exact placement of the needle tips was again verified by CT. RESULTS: In 4 attempts, a depiction of the joint space was not possible. Ultrasound and CT provided the same mean measurements of 1.2+/-0.2 cm, 2.0+/-0.3 cm, 3.0+/-0.2, and 4.0+/-0.5 cm for distances A, B, C, and D, respectively. All 10 needle tips were located in the joint space during simulated facet joint injections, as also verified by CT. DISCUSSION: This preclinical study suggests that ultrasound is a useful guiding tool for facet joint injections in the cervical spine.     

Prevalence of facet joint pain in chronic low back pain in postsurgical patients by controlled comparative local anesthetic blocks

OBJECTIVE: To evaluate the prevalence of facet joint pain in patients with chronic low back pain (CLBP) after surgical intervention(s). DESIGN: A prospective, nonrandomized, consecutive study. SETTING: An ambulatory interventional pain management setting. PARTICIPANTS: The prevalence of facet joint pain was evaluated in patients with CLBP after various surgical intervention(s) referred to an interventional pain management practice. The sample was derived from 282 patients with persistent CLBP after various surgical intervention(s). Of these, 242 patients consented to undergo interventional techniques. A total of 117 consecutive patients with chronic, nonspecific low back pain, after lumbar surgical intervention(s) were evaluated with controlled, comparative local anesthetic blocks. INTERVENTIONS: Controlled, comparative local anesthetic blocks (1% lidocaine or 1% lidocaine followed by .25% bupivacaine) under fluoroscopic visualization using 0.5mL to block each facet joint nerve. MAIN OUTCOME MEASURES: A positive response was defined as at least 80% reduction of pain with ability to perform previously painful movements. A positive response was considered to be pain relief from the lidocaine block lasting at least 1 hour or at least 2 hours or greater than duration of relief with lidocaine when bupivacaine was used. Controlled, comparative local anesthetic blocks were used to eliminate false-positive results. Valid information is only obtained by performing controlled blocks in the form of comparative local anesthetic blocks, in which, on 2 separate occasions, the same joint is anesthetized by using local anesthetics with different durations of action. If patients obtained appropriate response with both blocks, they were considered a positive. If they obtained appropriate response with lidocaine but not with bupivacaine, they were considered false-positive, whereas if the response was negative with lidocaine, they were considered negative. RESULTS: The prevalence of lumbar facet joint pain in patients with recurrent pain after various surgical intervention(s) was 16% (95% confidence interval, 9%-23%). The false-positive rate with a single block with lidocaine was 49%. CONCLUSIONS: Facet joints are clinically important pain generators in a small but significant proportion of patients with recurrent CLBP after various surgical intervention(s).     

Audit of conservative management of chronic low back pain in a secondary care setting--part I: facet joint and sacroiliac joint interventions

The work of a chronic back pain service in secondary care in the West Midlands is reported. The service offers acupuncture, spinal injection procedures, osteopathy and a range of other interventions for patients whose back pain has not responded to conservative management. This section of the report focuses on injection procedures for lumbar facet joint and sacroiliac joint pain, which have been shown to be the cause of chronic low back pain in 16-40% and 13-19% of patients respectively. Diagnosis relies on the use of intra-articular or sensory nerve block injections with local anaesthetic. Possible treatments following diagnosis include intra-articular corticosteroid, radiofrequency denervation (for facet joint pain) or ligament prolotherapy injections (for sacroiliac joint pain). The results of several hospital audits are reported. At six month follow up, 50% of 38 patients undergoing radiofrequency denervation following diagnostic blocks for facet joint pain had improved by more than 50%, compared to 29% of 34 patients treated with intra-articular corticosteroid injection. Sixty three per cent of 19 patients undergoing prolotherapy following diagnostic block injection for sacroiliac joint pain had improved at six months, compared to 33% of 33 who had intra-articular corticosteroid. Both radiofrequency denervation and sacroiliac prolotherapy showed good long-term outcomes at one year.     

Ultrasound-Guided Lumbar Plexus Block for Open Reduction and Internal Fixation of Hip Fracture

Purpose: Ultrasound technology has been applied to increase both efficacy and safety of certain peripheral nerve blocks. This case report describes the first successful ultrasound‐guided lumber plexus block. Clinical Features: We describe a 91‐year‐old woman with aortic stenosis who successfully underwent open reduction and internal fixation of a fractured right hip with a lumbar plexus block. Ultrasound provided direct visualization to help identify the anatomical structures and guide the block needle during performance of the block. Complete block of the lumbar plexus was attained within 15 min, and the surgical procedure was performed uneventfully. Conclusion: The use of ultrasound has gained popularity to perform peripheral nerve blocks. In this case report, a successful lumbar plexus block was performed with ultrasound guidance. By direct visualization, using this technology may potentially reduce complications associated with lumbar plexus blocks.