20. Meralgia Paresthetica

Meralgia paresthetica (MP) is a neurological disorder of the nervus cutaneous femoris lateralis (lateral femoral cutaneous nerve) (LFCN) characterized by a localized area of paresthesia and numbness on the anterolateral aspect of the thigh. Medical history and neurological examination are essential in making the diagnosis. However, red flags such as tumor and lumbar disc herniations must be ruled out. While the diagnosis of MP is essentially a clinical diagnosis, sensory nerve conduction velocity studies are a useful additional diagnostic tool. The first choice in management of MP is, besides treating the underlying cause, always a conservative approach. Simple measures such as losing weight and not wearing tight belts and/or trousers can be advised. Pharmacological therapy consists mainly of antineuropathic medication. Anatomical variants of the LFCN occur in a quarter of patients and may be the reason for negative response to diagnostic blocks. For interventional treatment of MP, such as local injection with anesthetics and corticosteroids or pulsed radiofrequency treatment of the LFCN, the evidence is limited. In particular, pulsed radiofrequency treatment of the LFCN should only take place in a study context.     

Treatment of meralgia paresthetica with ultrasound-guided pulsed radiofrequency ablation of the lateral femoral cutaneous nerve

Abstract: A 23‐year‐old female with an 18‐month history of left anterolateral thigh paresthesias and burning pain consistent with meralgia paresthetica was referred to our clinic after failing trials of physical therapy, nonsteroidal anti‐inflammatories, gabapentin, and amitriptyline. We performed 3 lateral femoral cutaneous nerve blocks with corticosteroid over a 4‐month period; however, each block provided only temporary relief. As this pain was limiting the patient’s ability to perform her functions as an active duty service member, we elected to perform a pulsed radiofrequency treatment of the lateral femoral cutaneous nerve with ultrasound guidance and nerve stimulation. After locating the lateral femoral cutaneous nerve with ultrasound and reproducing the patient’s dysthesia with stimulation, pulsed radiofrequency treatment was performed at 42°C for 120 seconds. The needle was then rotated 180° and an additional cycle of pulsed radiofrequency treatment was performed followed by injection of 0.25% ropivacaine with 4 mg of dexamethasone. At 1.5 and 3 month follow‐up visits, the patient reported excellent pain relief with activity and improved ability to perform her duties as an active duty service member. ?     

Ultrasound-guided blockade of the lateral femoral cutaneous nerve: technical description and review of 10 cases

Blockade of the lateral femoral cutaneous nerve (LFCN) is performed for therapeutic management of meralgia paresthetica and as a regional anesthetic technique. The conventional technique is associated with high failure rates secondary to variable LFCN anatomy. We describe a technique for blockade of the LFCN using ultrasound guidance. A cross-sectional view of the LFCN was obtained by identifying the anterior superior iliac spine, then moving a 14-to-7MHz linear array ultrasound probe in a medial caudal direction until the nerve was encountered. The needle was advanced to the LFCN under ultrasound guidance via a lateral to medial approach. Injection using dynamic ultrasound demonstrated excellent perineural spread. Ten subjects underwent successful blockade of the LFCN with this technique. Five subjects were obese. Use of ultrasound for precise needle placement allowed low injection volumes to be utilized. Theref were no complications. Ultrasound guidance can facilitate blockade of the LFCN for diagnostic and therapeutic purposes and may be particularly beneficial with patients with challenging surface anatomic landmarks, or when low volume injections are desired.     

心区交感神经阻滞对扩张型心肌病左室重塑的影响

目的　探讨心区交感神经阻滞对扩张型心肌病 (dilatedcardiomyopathy,DCM)左室重塑的影响 ,以寻求DCM治疗新法。方法　 2 0 0 0年 5月至 2 0 0 2年 5月临床诊断为DCM患者 6 0例 (符合WHO标准 ) ,随机分成治疗组和对照组。治疗组实施上胸段硬膜外阻滞 ,4周一疗程 ,适当辅以常规药物。对照组仅给予常规药物治疗。应用彩色多普勒超声诊断仪常规方法测量左室重塑指标。结果　治疗组症状体征缓解迅速 ,而对照组缓解较慢 ,有的患者无效甚至加重。治疗组收缩功能提高 ,左室重塑指标得以改善[LVEDD (71 7± 9 3)mmvs (6 6 2± 8 8)mm ,EF (31 1± 17 0 ) %vs (36 6± 12 0 ) % ,FS (12 0± 1 0 ) %vs(15 0± 3 0 ) % ,LVEDV (393 3± 14 4 8)mlvs (343 2± 137 1)ml,LVESV (2 82 5± 12 1 1)mlvs (2 2 7 3±10 8 6 )ml,LVmass (394 3± 10 0 7)gvs (372 1± 93 2 )g,P <0 0 5 ],而对照组无改善。结论　心区交感神经阻滞治疗DCM能中止并逆转DCM左室重塑。     

Ultrasound‐Guided Posterior Antebrachial Cutaneous Nerve Block: Technical Description and Block Distribution in Healthy Volunteers

The posterior antebrachial cutaneous nerve branches from the radial nerve proximal to the elbow and supplies sensation to the posterior aspect of the forearm. With a high‐frequency linear transducer, the posterior antebrachial cutaneous nerve was identified in 8 healthy volunteers. Under aseptic conditions and with an ultrasound‐guided in‐plane technique, 1% lidocaine was injected circumferentially around the nerve. In each participant, the block was successful, and neither incidental blocks of other nerves nor any other complications were observed. These results demonstrate that the posterior antebrachial cutaneous nerve can be blocked to provide anesthesia or analgesia to the posterior forearm.     

Perineural Air Injection as a Means of Prevention of Thermal Injury of the Sciatic Nerve During Radio Frequency Ablation

Objective. The purpose of this study was to determine whether perineural air injection before radio frequency (RF) ablation of thigh muscles can minimize thermal injury to the sciatic nerve. Methods. Eighteen percutaneous RF ablation procedures were performed in the thighs of 9 rabbits (control, n = 9, right thigh; experimental, n = 9, left thigh) with an internally cooled electrode (1‐cm active tip). In the control group, the tip of the electrode was located in posterior muscles 5 mm away from the sciatic nerve before ablation. In the experimental group, sonographically guided air injection into the perineural space was performed just before ablation. Animals were killed 7 days after ablation, and the presence or absence of pathologic changes of the sciatic nerves (axonal necrosis, myelin digestion, endoneurial fibrosis, perineurial fibrosis, and dystrophic calcification) in both groups were compared under an optical microscope. Results. Perineural air injection was achieved successfully with a single puncture in all rabbits in the experimental group. All of the pathologic findings were observed much more frequently in the control group, and the differences in the frequencies of axonal necrosis and myelin digestion of the sciatic nerve between the groups were clinically significant (P < .05). Conclusions. Perineural air injection may be useful for reducing the frequency of thermal injury during RF ablation of lesions adjacent to nerves.     

Temporary 6TH cranial nerve paralysis after accidental durotomy in endoscopic disc surgery

We present a unique case of 6th nerve palsy following accidental durotomy in endoscopic lumbar spine surgery, which has not been reported in the literature before. A 72- year-old female patient was admitted to our outpatient clinic complaining of right leg pain for 6 months. A 4/5 motor paresis was observed on her right toe with a positive Lasegue test at 45°. On her magnetic resonance imaging (MRI), a L5-S1 disc herniation was detected. The patient was planned for percutaneous endoscopic interlaminar disc surgery. The extruded disc was adherent to the dura. During removal, a dural tear was observed. She was relieved of her right leg pain immediately after surgery, but after 30 min postoperatively, she complained of double vision with left abducens nerve paralysis. On cranial MRI, no abnormality could be observed. Intravenous fluids were administered and the paralysis resolved on the postoperative 24th hour. The patient was discharged from the hospital and did not show any complaints on her follow-ups. A 6th nerve palsy can be caused due to alterations of intracranial pressure or mechanic injury. We believe that the durotomy following removing of the disc fragment caused a rapid drainage of CSF, leading to intracranial hypotension and injury of the abducens nerve. Intracranial pressure should be monitored perioperatively and brisk deteriorations has to result in immediate finishing of the surgery to avoid further secondary damage.     

两种不同局麻方法在经直肠前列腺穿刺活检术中的镇痛效果比较

目的：比较经直肠超声引导前列腺神经阻滞术和直肠内灌注2％利多卡因凝胶在前列腺穿刺活检术中的镇痛疗效。方法：160例接受经直肠超声引导13点前列腺系统穿刺活检术的患者随机分为A、B两组。A组患者84例，在经直肠超声引导下，于前列腺基底部，左、右两侧精囊与前列腺交接处分别注射1％利多卡因5ml，B组患者76例，于活检前5min直肠内灌注2％利多卡因凝胶10ml。采用视觉模拟评分（VAS）评估两组患者在穿刺活检术中的疼痛程度。结果：两组患者在平均年龄（t=0．73）、PSA水平（t=0．34）和前列腺体积（t=0．55）的差异无显著性（P〉0．05），具有可比性。A组患者VAS评分0～3分者76例，4～5分者6例，6～10分者2例。B组患者则分别为48例、18例、10例。两组患者平均疼痛评分（VAS）分别为1．2分、2．6分，差异具有高度显著性意义（t=4．73，P〈0．01）。两组患者均未出现局麻药的不良反应。结论：经直肠超声引导前列腺神经阻滞术的镇痛疗效明显优于直肠内灌注2％利多卡因凝胶，值得临床推广应用。     

Transient Facial Nerve Palsy After Occipital Nerve Block: A Case Report

Occipital nerve blocks are commonly performed to treat a variety of headache syndromes and are generally believed to be safe and well tolerated. We report the case of an otherwise healthy 24‐year‐old woman with left side‐locked occipital, parietal, and temporal pain who was diagnosed with probable occipital neuralgia. She developed complete left facial nerve palsy within minutes of blockade of the left greater and lesser occipital nerves with a solution of bupivicaine and triamcinolone. Magnetic resonance imaging of the brain with gadolinium contrast showed no abnormalities, and symptoms had completely resolved 4‐5 hours later. Unintended spread of the anesthetic solution along tissue planes seems the most likely explanation for this adverse event. An aberrant course of the facial nerve or connections between the facial and occipital nerves also might have played a role, along with the patient's prone position and the use of a relatively large injection volume of a potent anesthetic. Clinicians should be aware that temporary facial nerve palsy is a possible complication of occipital nerve block.     

Ultrasound‐Guided Suprainguinal Fascia Iliaca Technique Provides Benefit as an Analgesic Adjunct for Patients Undergoing Total Hip Arthroplasty

Analgesia after total hip arthroplasty is often accomplished by the fascia iliaca compartment block, traditionally performed below the inguinal ligament, to anesthetize both femoral and lateral femoral cutaneous nerves. The course of the lateral femoral cutaneous nerve below the inguinal ligament is variable as opposed to consistent above the inguinal ligament in the pelvis. In this case series including 5 patients, we demonstrate that an ultrasound‐guided suprainguinal fascia iliaca approach would consistently anesthetize the lateral femoral cutaneous nerve along with anterior cutaneous femoral nerve branches and provide cutaneous analgesia after total hip arthroplasty, as shown by decreased opioid consumption.     

俯卧位手术病人髋垫与术后股外侧皮神经损伤的相关性研究

[目的]研究手术病人俯卧位致股外侧皮神经损伤的相关因素。[方法]选择使用OSI-5803i多功能手术床的Jackson脊柱床面进行脊柱外科手术病人58例，通过记录手术时间、髂前上棘脂肪厚度、身体与髋垫接触的压迹面积、接触部位中心距髂前上棘距离及术后大腿前外侧有无异常感觉、何时出现症状、随访期间症状变化，共随访7d，对引起术后股外侧皮神经损伤的相关因素进行分析。[结果]手术时间、髋垫压迹横径、接触部位中心距髂前上棘距离与股外侧皮神经损伤相关。[结论]与俯卧位术后股外侧皮神经损伤相关的主要因素为手术时间、髋垫压迹横径及髋垫与髂前上棘的相对位置。     

Meralgia paresthetica

Meralgia paresthetica is an uncommon entrapment neuropathy involving the lateral femoral cutaneous nerve of the thigh. Symptoms include numbness, tingling and pain in the anterolateral thigh. The condition can be differentiated from other neurologic disorders by the typical exacerbating factors and the characteristic distribution of involvement. The course tends to be one of lifelong flare-ups, but these can usually be successfully managed with a conservative approach.     

Comparison of perineural platelet‐rich plasma and dextrose injections for moderate carpal tunnel syndrome: A prospective randomized,single‐blind,head‐to‐head comparative trial

Recent studies demonstrated the utility of perineural injection with platelet‐rich plasma (PRP) and 5% dextrose (D5W) as novel strategies for treatment of carpal tunnel syndrome (CTS). The present study comprised a prospective, randomized, single‐blind, head‐to head comparative trial to compare the 6‐month outcome of perineural injection with PRP or D5W in patients with moderate CTS. Fifty‐two patients with unilateral moderate CTS were enrolled and randomized into two groups: The PRP group received a single 3‐cc perineural injection of PRP under ultrasound guidance, and dextrose group received a single 3‐cc perineural injection of D5W under ultrasound guidance. The Boston Carpal Tunnel Syndrome Questionnaire score was used as the primary outcome. Secondary outcomes included cross‐sectional area (CSA) of the median nerve and electrophysiological assessments. Evaluations were performed at baseline and at 1, 3, and 6 months postinjection. All patients (26 patients per group) completed the study. Compared with the dextrose group, the PRP group demonstrated significant reductions in Boston Carpal Tunnel Syndrome Questionnaire function at 3 months (p = .044), distal motor latency at 6 months (p = .028), and CSA at 3 and 6 months (p = .010 and.018, respectively). A single perineural injection of PRP reduced the CSA of the median nerve more effectively than injection of D5W at 3 and 6 months postinjection for patients with moderate CTS.     

Cutaneous nerve transection for the management of intractable upper extremity pain caused by invasive squamous cell carcinoma

A recurrent clinical dilemma in the management of patients with painful metastatic lesions is achieving a balance between effective analgesic therapies versus intolerable side effects, in particular altered mental status. We present the case of an immunosuppressed patient post-lung transplant who was suffering from intractable pain caused by widely metastatic squamous cell carcinoma. The patient's progressive, excruciating neuropathic pain was localized to the area of the left wrist and forearm. Additionally, the patient complained of moderate pain at sites of tumor involvement on her right arm and scalp. Attempts to adequately manage her left upper extremity pain included a combination of pharmacologic treatments intended to treat neuropathic pain (gabapentin, SNRI, ketamine, opioids) and focused regional analgesia (infraclavicular infusion of local anesthetic). However, the patient developed intolerable side effects including altered mental status and delirium associated with the systemic agents and suboptimal control with the infraclavicular infusion. Given that the most severe pain was well localized, we undertook a diagnostic block of the cutaneous nerves of the left forearm. As this intervention significantly reduced her pain, we subsequently performed neurectomies to the left superficial radial nerve, lateral cutaneous nerve of the forearm and the posterior cutaneous nerve of the forearm. This resulted in immediate and continued relief of her left upper extremity pain without an altered mental status. Residual focal pain from lesions over her right arm and scalp was successfully managed with daily topical applications of lidocaine and capsaicin cream. Successful pain control continued until the patient's death five months later.     

Unusual disposition of lateral circumflex femoral artery: Anatomical description and clinical implications

The anatomical knowledge of arterial variations of lower limb is of utmost significance for the present day surgeons and interventional radiologists for minimizing complications during vascular reconstructive procedures, catheterization procedures and surgical intervention for embolism. Lateral Circumflex Femoral Artery(LCFA) isan important branch of Profunda Femoris artery and precise knowledge of its variations can be of great relevance during surgical and radiological procedures in femoral region. The present study reports a unique case of anomalous route taken by LCFA posterior to femoral nerve associated with a prominent muscular branch from Femoral artery mimicking the course of LCFA. Documentation of such variations is highly significant. It may serve as guideline for surgeons in reducing the incidence of postoperative complications where LCFA is used as a long vascular pedicle in anterolateral perforator thigh flap and in breast reconstruction after mastectomy. Ignorance of such variations can lead to fatal intraoperative haemorrhage and incapacitating sensory and motor deficit due to injury to femoral nerve branches which are closely related to these vessels.     

Malignant peripheral nerve sheath tumor in an elderly patient with superficial spreading melanoma: A case report

BACKGROUNDMalignant peripheral nerve sheath tumor (MPNST) is a type of spindle cell sarcoma originating from the peripheral nerve, which usually results in the corresponding nerve sign on magnetic resonance imaging (MRI). Patients with MPNST may also have neurofibromatosis type 1.CASE SUMMARYA 78-year-old male was admitted to the hospital due to a tumor in his left knee. He had a previous history of superficial spreading melanoma on the left thigh. Color Doppler ultrasonography showed a hypoechoic mass in the subcutaneous soft tissues of the medial left knee with an abundant rich blood flow. Computed tomography scanning did not show obvious signs of bone destruction, but the skin adjacent to the tumor was slightly thickened. MRI examination revealed that the hypervascular lesion was well-circumscribed, lobulated, invaded the surrounding soft tissues and demonstrated heterogeneous enhancement but lacked an entering and exiting nerve sign. The MRI result indicated the invasiveness of the tumor. The patient underwent a left knee joint mass expanded resection and the first histopathological examination showed a MPNST with positive surgical margins. Therefore, the second extended resection was performed, and the patient had a good outcome in the short term.CONCLUSIONMRI is a useful technique for revealing the biological characteristics of MPNST and provides clinical support for evaluation of the surgical area before operation.     

Role of sonography in the diagnosis and treatment of a ganglion cyst compressing the lateral branch of deep peroneal nerve

Selective compression neuropathy of the lateral branch of the deep peroneal nerve is rare. A 55‐year‐old woman with ankle instability and mild weakness of extension of the toes was examined with sonography (US), which revealed the presence of a ganglion cyst compressing selectively the lateral branch of the deep peroneal nerve. US‐guided aspiration of the cyst resulted in nerve decompression and progressive resolution of symptoms. This case demonstrates the importance of examining the deep peroneal nerve and its branches when performing US in the clinical setting of ankle instability. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45 :108–111, 2017;     

Effects of local lidocaine treatment before and after median nerve injury on mechanical hypersensitivity and microglia activation in rat cuneate nucleus

This study examined the relationship between microglia activation in the cuneate nucleus (CN) and behavioral hypersensitivity after chronic constriction injury (CCI) of the median nerve. We also investigated effects of local lidocaine pre‐ and post‐treatment on microglia activation and development of hypersensitivity in this model. By immunohistochemistry and immunoblotting, little immunoreactivity of OX‐42, a microglia activation marker, was detected in the CN of normal rats. As early as 1 day after CCI, there was a significant increase in OX‐42 immunoreactivity in the lesion side of CN, which reached a maximum at 14 days. Microinjection of minocycline, a microglia activation inhibitor, into the CN 1 day after CCI attenuated injury‐induced behavioral hypersensitivity in a dose‐dependent manner. Furthermore, the animals received 1%, 2% or 5% lidocaine 15 min prior to median nerve CCI (pre‐treatment), 5 h (early post‐treatment) or 1 day (late post‐treatment) after median nerve CCI. Pre‐treatment and early post‐treatment with 2% and 5% lidocaine, but not 1% lidocaine, attenuated OX‐42 immunoreactivity and behavioral hypersensitivity following median nerve injury. Late post‐treatment with 1%, 2%, or 5% lidocaine failed to decrease OX‐42 immunoreactivity and mechanical hypersensitivity in CCI rats. In conclusion, median nerve injury‐induced microglia activation in the CN modulated development of behavioral hypersensitivity. High‐concentration lidocaine was effective in decreasing microglia activation in the CN and in attenuating neuropathic pain sensations at the early stage following nerve injury, when microglia had not yet been activated.     

股前外侧游离穿支皮瓣移植修复头面四肢肿瘤切除术后的软组织缺损

背景:传统股前外侧皮瓣移植的临床应用已非常广泛,新一代带穿支游离皮瓣移植在国内尚处于初始阶段。目的:观察头面部和四肢肿瘤切除术后应用股前外侧穿支皮瓣移植修复方法及其修复效果。设计:病例分析。单位:南华大学第一附属医院。对象:选择2004-04/2006-04在南华大学第一附属医院烧伤整形外科及多伦多大学多伦多总医院整形外科收治的16例需要皮瓣移植的患者,所有患者软组织缺损不能直接缝合导致肌腱、血管、神经、骨质外露。男13例,女3例,年龄26～72岁。因头面肿瘤切除后造成软组织缺损、骨质外露修复9例,平均50岁;因四肢肿瘤切除术后造成软组织缺损、骨质外露修复7例,平均为39岁,所有患者均对手术项目知情同意。方法:患者均采取全身麻醉,气管插管。医生分两组同时或先后进行手术。肿瘤切除由头颈外科或骨外科医生承担,肿瘤切除后由整形外科医生承担修复任务,整形外科医生先确定受区血管床,并游离,准备好受区血管。其中有2例游离出神经断端做神经修复。根据创口情形切取穿支皮瓣:于髂前上棘及髌骨前外上缘连线作为皮瓣的纵轴线,确定中点,并在中点区域设计所需要的皮瓣。皮瓣最大面积达28cm×15cm,在皮瓣范围内用超声多普勒仪确定主要穿支浅出点(即超声回音最强点)一二个。沿设计线切开皮肤皮下,在放大镜下逐步切开分离皮下组织与深筋膜。遇到主要穿支后,确保一二支主要穿支不受损伤;并沿着穿支血管追踪分离深筋膜、肌肉或肌间隔,及至所需要的血管蒂的长度和所需要的血管管径的大小。必要时保留股前外侧皮神经,本组修复皮神经两例。供瓣区创面直接闭合,放负压引流。在显微镜下用9-0尼龙线吻合血管,用10-0尼龙线吻合神经,间断缝合皮瓣与受区创缘,同时放负压引流于瓣下。头部创口缝线术后9～11d拆除,四肢创口的缝线术后12～15d拆除,供瓣区缝线术后15d以后拆除,引流管在术后3d拔除。观察所有患者术后愈合情况(Ⅰ期愈合:术后伤口按期愈合;Ⅱ期愈合:术后伤口未按期愈合),同时观察皮瓣是否坏死、伤口是否裂开等。主要观察指标:所有患者皮瓣移植后成活情况、皮瓣供区和受区的外形及功能。结果:纳入需要皮瓣移植的患者16例均进入结果分析。15例患者移植皮瓣全部成活,1例皮瓣大部分成活,皮瓣远端小部分坏死。伤口Ⅰ期愈合14例,Ⅱ期愈合2例(1例皮瓣远端约2.5cm宽的皮瓣缺血坏死,清除坏死组织后直接缝合愈合,另1例面部上端与皮远瓣区伤口有约3cm长裂开,经换药、再缝合处理后愈合)。所有患者伤口愈合后外形满意,均未见明显疤痕,下肢负重、行走不受影响。结论:股前外侧穿支皮瓣游离移植,对供区损伤小,对受区修复效果好,是一种较理想的修复头面和四肢肿瘤清除术后软组织缺损的方法。