Anterior Femoral Cutaneous Nerve Research Articles

Cryoneurolysis Is a Safe, Effective Modality to Improve Rehabilitation after Total Knee Arthroplasty.

Although long term pain and mobility outcomes in total knee arthroplasties (TKA) are successful, many patients experience significant amount of debilitating pain during the immediate post-operative period that necessitates narcotic use. Percutaneous cryoneurolysis to the infrapatellar saphenous and anterior femoral cutaneous nerves may help to better restore function and rehabilitation after surgery while limiting narcotic consumption. A retrospective chart review of primary TKA patients receiving pre-operative cryoneurolysis from 2019 to 2020 was performed to assess total opioid morphine milligram equivalents (MME) consumed inpatient and at interval follow-up. Demographics and medical comorbidities were compared between cryoneurolysis and age-matched control patients to assess baseline characteristics. Functional rehabilitation outcomes, including knee range of motion (ROM), ambulation distance, and Boston AM-PAC scores, as well as patient reported outcomes using the KOOS JR and SF-12 scores were analyzed using STATA 17 Software. The analysis included 29 cryoneurolysis and 28 age-matched control TKA patients. Baseline demographics and operative technique were not significant between groups. Although not statistically significant, cryoneurolysis patients had a shorter length of stay (2.5 vs. 3.5 days) and overall less inpatient and outpatient MME requirements. Cryoneurolysis patients had statistically significant improved 6-week ROM and 1-year follow-up KOOS JR and SF-12 mental scores compared to the control. There were no differences in complication rates. Cryoneurolysis is a safe, effective treatment modality to improve active functional recovery and patient satisfaction after TKA by reducing MME requirements. Patients who underwent cryoneurolysis had on average fewer MME prescribed during the perioperative period, improved active ROM, and improved patient-reported outcomes with no associated increased risk of infections, deep vein thrombosis, or neurologic complications.

Selective MR neurography-guided anterior femoral cutaneous nerve blocks for diagnosing anterior thigh neuralgia: anatomy, technique, diagnostic performance, and patient-reported experiences.

To evaluate the clinical utility of selective magnetic resonance neurography-(MRN)-guided anterior femoral cutaneous nerve (AFCN) blocks for diagnosing anterior thigh neuralgia. Following institutional review board approval and informed consent, participants with intractable anterior thigh pain and clinically suspected AFCN neuralgia were included. AFCN blocks were performed under MRN guidance using an anterior groin approach along the medial sartorius muscle margin. Outcome variables included AFCN identification on MRN, technical success of perineural drug delivery, rate of AFCN anesthesia, complications, total procedure time, patient-reported procedural experiences, rate of positive diagnostic AFCN blocks, and positive subsequent treatment rate. Eighteen MRN-guided AFCN blocks (six unilateral and six bilateral blocks) were performed in 12 participants (6 women; age, 49 (30-65) years). Successful MRN identified the AFCN, successful perineural drug delivery, and AFCN anesthesia was achieved in all thighs. No complications occurred. The total procedure time was 19 (10-28) min. Patient satisfaction and experience were high without adverse MRI effects. AFCN blocks identified the AFCN as the symptom generator in 16/18 (89%) cases, followed by 14/16 (88%) successful treatments. Our results suggest that selective MR neurography-guided AFCN blocks effectively diagnose anterior femoral cutaneous neuralgia and are well-tolerated.

Effect of ultrasound-guided selective sensory nerve blockade of the knee on pain management compared with periarticular injection for patients undergoing total knee arthroplasty: A prospective randomized controlled trial

BackgroundUltrasound-guided selective sensory nerve blockade (SSNB) of the knee, including an adductor canal block (ACB), anterior femoral cutaneous nerve block, and infiltration between the popliteal artery and posterior capsule of the knee may provide effective motor-sparing knee analgesia for total knee arthroplasty (TKA). We hypothesized that the SSNB would manage pain better on ambulation 24 hours postoperatively compared to periarticular infiltration (PAI), when combined with postoperative continuous ACB. MethodsSeventy-two patients undergoing elective TKA under spinal anesthesia were randomly assigned to either SSNB (SSNB group) or intraoperative PAI (PAI group). All patients received postoperative multimodal analgesia, including continuous ACB. The primary outcome was pain on ambulation 24 hours postoperatively. Secondary outcomes included rest and dynamic numerical rating scale pain score, intravenous morphine requirement, functional performance measures, adverse events, satisfaction, and length of stay. ResultsThere was no difference in pain score during movement between the groups (mean difference −0.48 [−1.38 to 0.42], p = 0.3) and other immediate overall pain scores 24 hours postoperatively. Patients in the SSNB group had significantly lower intravenous morphine requirement than the PAI group for 48 hours postoperatively (0 [0, 0] vs. 0 [0, 2]; p = 0.008). There was no intergroup difference in the performance-based measures, satisfaction, and length of stay. ConclusionsThe SSNB did not provide superior postoperative analgesia, or improvement in immediate functional performance. However, it may result in lower opioid consumption postoperatively when compared with the intraoperative PAI.

The analgesic efficacy of anterior femoral cutaneous nerve block in combination with femoral triangle block in total knee arthroplasty: a randomized controlled trial.

BackgroundUltrasound-guided femoral triangle block (FTB) can provide motor-sparing anterior knee analgesia. However, it may not completely anesthetize the anterior femoral cutaneous nerve (AFCN). We hypothesized that an AFCN block (AFCNB) in combination with an FTB would decrease pain during movement in the immediate 12 h postoperative period compared with an FTB alone.MethodsEighty patients scheduled to undergo total knee arthroplasty were randomized to receive either FTB alone (FTB group) or AFCNB with FTB (AFCNB + FTB group) as part of the multimodal analgesic regimen. The primary outcome was pain during movement at 12 h postoperatively. Secondary outcomes included numeric rating scale (NRS) pain scores, incidence of surgical incision site pain, intravenous morphine consumption, immediate functional performance, patient satisfaction, and length of hospital stay.ResultsThe NRS pain scores on movement 12 h postoperatively were significantly lower in the AFCNB + FTB group than in the FTB group (mean difference: –2.02, 95% CI: –3.14, –0.89, P < 0.001). The incidence of pain at the surgical incision site at 24 h postoperatively and morphine consumption within 48 h postoperatively were significantly lower (P < 0.001), and quadriceps muscle strength at 0° immediately after surgery was significantly greater in the AFCNB + FTB group (P = 0.04).ConclusionsThe addition of ultrasound-guided AFCNB to FTB provided more effective analgesia and decreased opioid requirement compared to FTB alone after total knee arthroplasty and may enhance immediate functional performance on the day of surgery.

Cryoanalgesia of the anterior femoral cutaneous nerve (AFCN) for the treatment of neuropathy-mediated anterior thigh pain: anatomy and technical description.

To describe and illustrate the magnetic resonance imaging (MRI) anatomy of the anterior femoral cutaneous nerve (AFCN) and a new technique for cryoanalgesia of the AFCN for long-term analgesic treatment of recalcitrant AFCN-mediated neuropathic pain. Using a procedural high-resolution MRI technique, we describe the MRI anatomy of the AFCN. Three patients (mean age, 48years; range, 41-67years) with selective nerve block-verified recalcitrant AFCN-mediated anterior thigh pain were enrolled to undergo cryoanalgesia of the AFCN. Procedures were performed under MRI guidance using clinical wide-bore MR imaging systems and commercially available cryoablation system with MR-conditional probes. Outcome variables included technical success, clinical effectiveness including symptom relief measured on an 11-point visual analog scale, frequency of complications, and procedure time. Procedural MRI allowed to successfully demonstrate the course of the AFCN, accurate cryoprobe placement, and monitoring of the ice ball, which resulted in technically successful iceball growth around the AFCN in all cases. All procedures were clinically effective, with median pain intensity decreasing from 8 (7-9) before the procedure to 1 (0-2) after the procedure. The cryoanalgesia effect persisted during a 12-month follow-up period in all three patients. No major complications occurred. The average total procedure time was 98min (range, 85-125min). We describe the MRI anatomy of the AFCN and a new technique for cryoanalgesia of the AFCN using MRI guidance, which permits identification of the AFCN, selective targeting, and iceball monitoring to achieve long-term AFCN-mediated neuropathic pain relief.

Anesthesia of the anterior femoral cutaneous nerves for total knee arthroplasty incision: randomized volunteer trial

Background and objectivesFor pain relief after total knee arthroplasty (TKA), an injection at the midthigh level may produce analgesia inferior to that of a femoral nerve block as the anterior...

The The first report of pure neuritic leprosy with involvement of the anterior femoral cutaneous nerve

We describe the case of a young man, 22 years old, a household contact of leprosy, presenting paresthesia in the right leg and great thickening in the anterior femoral nerve and in the ipsilateral sural nerve. There were no typical dermatological lesions of leprosy. Ultrasonography confirmed the clinical finding. The clinical diagnosis of the disease was established and the patient started multibacillary-multidrug therapy, obtaining improvement of the initial symptomatology.

Accuracy of Ultrasound‐Guided Localization of the Peripatellar Plexus for Knee Pain Management

IntroductionPain associated with arthritis of the knee and its ultimate treatment, total knee arthroplasty, can be considerable and has historically been addressed with a variety of treatment modalities including an emphasis on opioid usage for severe pain. While opioids provide effective pain relief, they have many unwanted side effects including nausea, vomiting, constipation, urinary retention, mental status changes, and respiratory depression. Alternatively, patients experiencing knee pain have benefited from anesthetization through cryoneurolysis of the cutaneous nerves of the anterior thigh and knee that contribute to the peripatellar plexus. The purpose of this study was to assess the accuracy of ultrasound‐guided localization of the peripatellar plexus on cadaveric lower extremities.Materials and MethodsUltrasound was used to locate the anterior femoral cutaneous nerve (AFCN), the infrapatellar branch of the saphenous nerve (IPSN), and the lateral femoral cutaneous nerve (LFCN) in the right and left lower extremities of two female and three male, lightly embalmed anatomical donors. Upon identifying a potential candidate, methylene blue was injected under ultrasound guidance. Confidence of identification for each site was scored as low, medium, or high at the time of injection based upon the clarity and difficulty in locating each of the cutaneous nerves via ultrasound. The three points of injection for each limb ware marked, and blunt dissection subsequently used to confirm the identification of each structure. A successful attempt was defined as MB staining directly within the nerve epineurium and an unsuccessful attempt was defined as MB staining of the subcutaneous loose connective tissue with no direct staining of nerve epineurium.ResultsIn total, 30 injection sites were analyzed. High confidence was reported 60% (18/30) of the time, medium confidence was reported 23.3% (7/30) of the time, and low confidence was reported 16.7% (5/30) of the time. All five of the reports of low confidence were associated with IPSN injections. Dissection revealed successful injections in 90% (27/30) of the injection attempts, and unsuccessful injections in 10% (3/30) of the attempts. All three unsuccessful injection attempts were associated with IPSN injections and resulted in staining of the great saphenous vein.DiscussionDependency and addiction that can occur with chronic opioid use have been brought to the national forefront in what is now considered to be an “Opioid Crisis”. To reduce the dependence on opioids, multimodal approaches to pain including cryoneurolysis have been advocated. This study confirmed the accuracy of ultrasound‐guided localization of cutaneous nerves of the peripatellar plexus. Improving the precision in identifying these nerves is crucial in reducing patient morbidity, treatment times, and associated treatment costs.Support or Funding InformationThis work was supported by Myoscience A. Ultrasound location of the AFCN within the subcutaneous loose connective tissue of the thigh, just superficial to the fasciae latae and quadriceps muscles. B. Injection of methylene blue into AFCN via ultrasound guidance.imageA. Ultrasound location of the AFCN within the subcutaneous loose connective tissue of the thigh, just superficial to the fasciae latae and quadriceps muscles. B. Injection of methylene blue into AFCN via ultrasound guidance.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Abstract WP379: Femoral Neuropathy Following Transfemoral Neuroendovascular Procedures. An Analysis of a Prospective Registry

Background: Although femoral neuropathy is recognized as an adverse consequence following trans-femoral neuro-endovascular procedures, no reliable estimates are available. We analyzed data from a prospective registry to ascertain the frequency and characteristics of femoral neuropathy following trans-femoral neuro-endovascular procedures. Methods: Consecutive patients who underwent neuro-endovascular procedures through the trans-femoral route were included. Detailed assessment was performed if any patient reported occurrence of sensory or motor symptoms in the femoral or lower extremity region including neurological examination (sensory/motor deficits) and femoral region ultrasound. Results: Femoral neuropathy was diagnosed following 4 of 270 neurovascular procedures with an occurrence rate of 1.5% (95% confidence intervals 0.4% - 3.7%). The symptoms were exclusively sensory without any motor involvement. The femoral neuropathy appeared to involve anterior femoral cutaneous nerves in all and medial cutaneous branches in 2 patients, and more than one nerve distribution in one patient in whom lateral cutaneous nerve appeared to be involved. All patients reported resolution of symptoms within a period ranging from 1 week to 2 months. No local hematoma or arterial pseudo-aneurysm was identified at femoral region ultrasound. Conclusions: Femoral neuropathy is a rare occurrence following trans-femoral neuro-endovascular procedures and usually occurs with pure sensory manifestations with complete resolution.

Femoral Neuropathy Following Transfemoral Neuroendovascular Procedures. An Analysis of a Prospective Registry.

Although femoral neuropathy is recognized as an adverse consequence following transfemoral neuroendovascular procedures, no reliable estimates are available. We analyzed data from a prospective registry to ascertain the frequency and characteristics of femoral neuropathy following transfemoral neuroendovascular procedures. Consecutive patients who underwent neuroendovascular procedures through the transfemoral route were included. Detailed assessment was performed if any patient reported occurrence of sensory or motor symptoms in the femoral or lower extremity region including neurological examination (sensory/motor deficits) and femoral region ultrasound. Femoral neuropathy was diagnosed following 4 of 270 neurovascular procedures with an occurrence rate of 1.5% (95% confidence intervals=.4-3.7%). The symptoms were exclusively sensory without any motor involvement. The femoral neuropathy appeared to involve anterior femoral cutaneous nerves in all and medial cutaneous branches in 2 patients, and more than one nerve distribution in 1 patient in whom lateral cutaneous nerve appeared to be involved. All patients reported resolution of symptoms within a period ranging from 1 week to 2 months. No local hematoma or arterial pseudoaneurysm was identified at femoral region ultrasound. Femoral neuropathy is a rare occurrence following transfemoral neuroendovascular procedures and it usually occurs with pure sensory manifestations with complete resolution.

Ultrasound Imaging for the Cutaneous Nerves of the Extremities and Relevant Entrapment Syndromes: From Anatomy to Clinical Implications.

Cutaneous nerve entrapment plays an important role in neuropathic pain syndrome. Due to the advancement of ultrasound technology, the cutaneous nerves can be visualized by high-resolution ultrasound. As the cutaneous nerves course superficially in the subcutaneous layer, they are vulnerable to entrapment or collateral damage in traumatic insults. Scanning of the cutaneous nerves is challenging due to fewer anatomic landmarks for referencing. Therefore, the aim of the present article is to summarize the anatomy of the limb cutaneous nerves, to elaborate the scanning techniques, and also to discuss the clinical implications of pertinent entrapment syndromes of the medial brachial cutaneous nerve, intercostobrachial cutaneous nerve, medial antebrachial cutaneous nerve, lateral antebrachial cutaneous nerve, posterior antebrachial cutaneous nerve, superficial branch of the radial nerve, dorsal cutaneous branch of the ulnar nerve, palmar cutaneous branch of the median nerve, anterior femoral cutaneous nerve, posterior femoral cutaneous nerve, lateral femoral cutaneous nerve, sural nerve, and saphenous nerve.

Novel Demonstration of the Anterior Femoral Cutaneous Nerves using Ultrasound.

Neuropathy of the intermediate (IFCN) and medial femoral cutaneous nerve (MFCN) is a potential iatrogenic complication of thigh surgery and its diagnosis is limited. This study aimed to evaluate the possibility of the visualization and diagnostic assessment of the IFCN and MFCN with high-resolution ultrasound (HRUS). In this study, HRUS with high-frequency probes (15 - 22MHz) was used to locate the IFCN and the MFCN in 16 fresh cadaveric lower limbs. The correct identification of the nerves was verified by ink-marking and consecutive dissections at sites correlating to nerve positions (R1 - 3), namely, the origin, the mid portion, and the distal portion, respectively. 12 cases with suspected IFCN and MFCN lesions referred to our clinic for HRUS examinations were also assessed. Anatomical dissection confirmed the correct identification of the IFCN in 16/16 branches at all of the different locations (100 %). MFCN was correctly identified at R1 + 3, in all cases (16/16; 100 %), and in 14/16 cases (88 %) at (R2). 12 cases of patients with IFCN and MFCN pathologies (all of iatrogenic origin) were identified. 9 instances of structural damage were visible on HRUS, and all pathologies were confirmed by almost complete resolution of symptoms after selective HRUS-guided blocks with 0.5 - 1 ml lidocaine 2 %. This study confirms that the IFCN and the MFCN can be reliably visualized with HRUS throughout the course of these nerves, both in anatomical specimens and in patients.

Percutaneous freezing of sensory nerves prior to total knee arthroplasty

BackgroundTotal knee arthroplasty (TKA) is a common procedure resulting in significant post-operative pain. Percutaneous cryoneurolysis targeting the infrapatellar branch of the saphenous nerve and anterior femoral cutaneous nerve could relieve post-operative knee pain by temporarily blocking sensory nerve conduction. MethodsA retrospective chart review of 100 patients who underwent TKA was conducted to assess the value of adding perioperative cryoneurolysis to a multimodal pain management program. The treatment group consisted of the first 50 patients consecutively treated after the practice introduced perioperative (five days prior to surgery) cryoneurolysis as part of its standard pain management protocol. The control group consisted of the 50 patients treated before cryoneurolysis was introduced. Outcomes included hospital length of stay (LOS), post-operative opioid requirements, and patient-reported outcomes of pain and function. ResultsA significantly lower proportion of patients in the treatment group had a LOS of ≥2days compared with the control group (6% vs. 67%, p<0.0001) and required 45% less opioids during the first 12weeks after surgery. The treatment group reported a statistically significant reduction in symptoms at the six- and 12-week follow-up compared with the control group and within-group significant reductions in pain intensity and pain interference at two- and six-week follow-up, respectively. ConclusionsPerioperative cryoneurolysis in combination with multimodal pain management may significantly improve outcomes in patients undergoing TKA. Promising results from this preliminary retrospective study warrant further investigation of this novel treatment in prospective, randomized trials. Level of evidenceIII

Multibranch anastomotic variant of the Lateral Femoral Cutaneous Nerve: possible implications in neurosurgical practice

Dear Editor, The anatomy and topography of the lateral femoral cutaneous (LFCN) and genitofemoral (GFN) nerves is known to have some variability [6]. Their formation and distribution may complicate the outcome of several surgical procedures, such as extraperitoneal approaches to the anterior and lateral lumbar spine [1, 2], rendering these nerves more vulnerable to iatrogenic injury. During a routine dissection of a formalin-fixed, 78-yearold male cadaver, a variant left LFCN was encountered. In the pelvis, the LFCN originated from the L2/L3 roots and emerged typically from the lateral border of the psoas major (PM) muscle. The nerve gave off a lateral accessory LFCN and a medial accessory anterior femoral cutaneous nerve branch, at 5.6 cm and 7.2 cm from the lateral border of the PM muscle, respectively. The GFN, after penetrating the PM muscle, branched off at 3.4 cm prior to the inguinal ligament (IL), providing a lateral nerve that anastomosed with the two LFCN branches below the IL level (Fig. 1a). The three nerve branches passed separately behind the IL and anastomosed 1.1 cm below the IL level, creating a multibranch octopus-like formation that eventually gave off six terminal nerve branches providing sensory supply to the anterolateral thigh (Fig. 1b). Both GFN and LFCN constitute branches of the lumbar plexus [6]. In GFN neuropathy, the symptomatology includes sensory loss and paresthesia over the GFN distribution area. In our case, the GFN anastomosed with the LFCN below the IL level; thus GFN neuralgia may present with sensory abnormalities such as numbness in the anterolateral and lateral thigh. LFCN injury leads to “meralgia paresthetica”, a disorder presenting with paresthesia and numbness over the LFCN supplied area [4]. The IL constitutes a potential entrapment site; in our case, three nerve branches passed behind the IL, jeopardizing nerve traction and neuropathy, leading to increased risk of producing such symptoms. Surgical treatment of “meralgia paresthetica” mainly includes nerve decompression or neurolysis and transposition of the trapped nerve branch [5]. Neurectomy can be also done in cases where other surgical treatments have failed [3]. The presence of multiple nerve branches passing behind the IL may provoke recurrence of symptoms if the surgeon does not identify the responsible nerve branch, although this multinerval supply may be useful in preserving sensation in the affected area after resection of the injured branch. Both LFCN and GFN can be injured during a lateral retroperitoneal approach to the lumbar spine [1, 2]. It is also challenging to recognize possible variants in surgery. Due to the fact that their activity is difficult if not impossible to be monitored reliably with neurophysiology intraoperatively, this type of injury usually remains unnoticed during surgery, with patients complaining for thigh numbness postoperatively [2]. Fortunately, the symptoms tend to resolve within weeks. G. K. Paraskevas :K. Natsis :M. Tzika Department of Anatomy, Faculty of Medicine, Aristotle University, Thessaloniki, Greece

Prolonged knee pain relief by saphenous block (new technique)

Pain in the knee joint can be from a variety of reasons. It can be either from the joint itself, it can be myofascial or it can be neuropathy, radicular pain. The myofascial component can be in different forms, namely, collateral ligament pain, bursitis, tendinitis, and so on. This responds well to local injections of steroids. Pain from the joint can be because of osteoarthritis (OA), rheumatoid arthritis or any other variety of arthritis. Among these osteoarthritis is the most common and naturally occurring pain. There are several modalities used for managing pain in the knee joint. They include medicines and physiotherapy, intra-articular steroid injection, intra-articular Hyalgan, Synvisc injection, prolotherapy, genicular nerve block, ablation, intra-articular pulsed radio frequency (PRF) ablation, acupuncture, injection of platelet-rich plasma in the joint, total knee replacement, high tibial osteotomy, arthroscopy and lavage, and so on. All these modalities have their pros and cons. Literature and experience state that the pain relief provided may last for a few months with these modalities except in surgical interventions in advanced OA. The saphenous nerve is termination of femoral nerve and it is essentially sensory nerve. It supplies the medial compartment and some part of the anterior compartment of the knee joint. This nerve has been blocked near the knee joint by way of infiltration by surgeons and anesthetists, for relief of pain after knee surgery, with varying pain relief of postoperative pain. When we block the saphenous in the mid thigh in the sartorial canal, the fluid tends to block the medial branch of the anterior femoral cutaneous nerve also. It is hypothesized that this may give complete medial and anterior knee pain relief and as most of the knee OA patients have medial and anterior knee pain, this may prove useful. Use of ultrasonography helps to locate the nerve better, ensuring perfection. An effort has been made to block this nerve in the sartorial canal with steroid and LA under ultrasonography (USG) guidance and observe the results. Patients have received very good pain relief (95 - 100%) for a substantially long time (up to four years).

Anatomical Variations of the Lumbar Plexus: A Descriptive Anatomy Study with Proposed Clinical Implications

This study used dissection of 34 lumbar plexes to look at the prevalence of anatomical variations in the lumbar plexus and the six peripheral branches from the origin at the ventral roots of (T12) L1-L4 to the exit from the pelvic cavity. Prevalence of anatomical variation in the individual nerves ranged from 8.8–47.1% with a mean prevalence of 20.1%. Anatomical variations included absence of the iliohypogastric nerve, an early split of the genitofemoral nerve into genital and femoral branches, an aberrant segmental origin for the lateral femoral cutaneous nerve, bifurcation of the lateral femoral nerve prior to exiting the pelvic cavity, bifurcation of the femoral nerve into two to three slips separated by psoas major muscle fibers, the presence of a single anterior femoral cutaneous nerve rather than the normal presentation of two separate anterior femoral cutaneous branches, and the presence of an accessory obturator nerve. Comparison with relevant research literature showed a wide variation in reported prevalence of the anatomical variations noted in this study. Clinical implications and directions for future research are proposed.

Neurofibromatous sensory neuropathy of the thigh in a 7-year-old boy

Neuropathy is considered to be an unusual complication of neurofibromatosis 1 (NF1). Neurofibromatous neuropathy is extremely rare in the setting of paediatric age group, pure sensory mononeuropathy and NF1. The following is a description of a 7-year-old boy who presented with complains of discomfort and parasthesia on the anterior aspect of his left thigh which is an unusual mode of presentation and site of involvement. Clinical examination and imaging revealed an isolated sensory neuropathy of the left anterior femoral cutaneous nerve of the thigh secondary to plexiform neurofibromatosis involving the L1-L4 nerve roots and the anterior femoral cutaneous nerve of thigh. The main abnormality in this patient was segmental hypertrophy of the left lower limb and dilatation of left lumbar neural foramens. Subtotal excision of the neurofibromas of the anterior femoral cutaneous nerve was performed and the patient was asymptomatic at the end of 27 months (2.25 years) of followup. Although the result of treatment in this case was good, long-term followup is necessary in view of greater risk of malignant transformation and development of spinal deformity and overall long-term poor prognosis in this particular patient subgroup of NF1.

The Safety and Efficacy of a Percutaneous Closure Device in Patients Undergoing Uterine Artery Embolization

The use of suture-mediated closure devices (SMCDs) in patients undergoing uterine artery embolization (UAE) for symptomatic leiomyomata is controversial. With recent literature suggesting a higher complication rate with the use of SMCDs, their use in this specific population has been questioned. The purpose of this study is to assess the safety and efficacy of SMCDs specifically for those patients undergoing UAE for symptomatic uterine leiomyomata. A prospective database was established in a single high-volume medical center for patients undergoing UAE for symptomatic leiomyomata. Data were tracked prospectively, with technical outcome and complication rates serving as endpoints. UAE was performed in 342 consecutive patients from January 2001 to September 2003. The SMCD was used in 328 of these patients (96%). Successful primary hemostasis was achieved in 320 of 328 patients (97%), with additional manual compression required in the remaining eight patients (3%). No major complications were observed. Minor complications consisted of minor hematomas in four women (1%) and anteriomedial thigh pain in 68 women (21%) within 1 month of follow-up, resulting in an overall complication rate of 22%. All symptoms related to anteromedial thigh pain ipsilateral to the arterial puncture site were managed conservatively with 1 week of oral nonsteroidal antiinflammatory medication. The SMCD provided safe and effective hemostasis in patients undergoing UAE. Transient thigh discomfort, which may result from irritation of the anterior femoral cutaneous nerves (femoral neuralgia syndrome), was uniformly relieved with nonsteroidal antiinflammatory therapy.

Evoked potentials elicited by stimulation of the lateral and anterior femoral cutaneous nerves in meralgia paresthetica.

Seventy-five consecutive patients with clinical symptoms and signs of meralgia paresthetica underwent bilateral somatosensory evoked potential (SEP) studies involving stimulation of skin areas innervated by the lateral and anterior femoral cutaneous nerves of the thighs. The most common abnormality was an absolute lateral femoral cutaneous SEP latency > 40 ms in 35 patients (47%), followed by an absent response in 14 patients (19%), an absolute latency < 40 ms but amplitude reduction > 50% compared with the contralateral response in 8 patients (11%), and an absolute latency < 40 ms but > 5 ms interside latency difference in 5 patients (7%). Anterior femoral cutaneous SEPs were of value in distinguishing meralgia paresthetica from a proximal lumbar radiculopathy in an additional 4 patients and confirming bilateral meralgia paresthetica in 10 patients.

Anterior lumbar fusion with titanium threaded and mesh interbody cages

The authors report their experience with 42 patients in whom anterior lumbar fusion was performed using titanium cages as a versatile adjunct to treat a wide variety of spinal deformity and pathological conditions. These conditions included congenital, degenerative, iatrogenic, infectious, traumatic, and malignant disorders of the thoracolumbar spine. Fusion rates and complications are compared with data previously reported in the literature. Between July 1996 and July 1999 the senior authors (C.I.S., R.P.N., and M.J.R.) treated 42 patients by means of a transabdominal extraperitoneal (13 cases) or an anterolateral extraperitoneal approach (29 cases), 51 vertebral levels were fused using titanium cages packed with autologous bone. All vertebrectomies (27 cases) were reconstructed using a Miami Moss titanium mesh cage and Kaneda instrumentation. Interbody fusion (15 cases) was performed with either the BAK titanium threaded interbody cage (in 13 patients) or a Miami Moss titanium mesh cage (in two patients). The average follow-up period was 14.3 months. Seventeen patients had sustained a thoracolumbar burst fracture, 12 patients presented with degenerative spinal disorders, six with metastatic tumor, four with spinal deformity (one congenital and three iatrogenic), and three patients presented with spinal infections. In five patients anterior lumbar interbody fusion (ALIF) was supplemented with posterior segmental fixation at the time of the initial procedure. Of the 51 vertebral levels treated, solid arthrodesis was achieved in 49, a 96% fusion rate. One case of pseudarthrosis occurred in the group treated with BAK cages; the diagnosis was made based on the patient's continued mechanical back pain after undergoing L4-5 ALIF. The patient was treated with supplemental posterior fixation, and successful fusion occurred uneventfully with resolution of her back pain. In the group in which vertebrectomy was performed there was one case of fusion failure in a patient with metastatic breast cancer who had undergone an L-3 corpectomy with placement of a mesh cage. Although her back pain was immediately resolved, she died of systemic disease 3 months after surgery and before fusion could occur. Complications related to the anterior approach included two vascular injuries (two left common iliac vein lacerations); one injury to the sympathetic plexus; one case of superficial phlebitis; two cases of prolonged ileus (greater than 48 hours postoperatively); one anterior femoral cutaneous nerve palsy; and one superficial wound infection. No deaths were directly related to the surgical procedure. There were no cases of dural laceration and no nerve root injury. There were no cases of deep venous thrombosis, pulmonary embolus, retrograde ejaculation, abdominal hernia, bowel or ureteral injury, or deep wound infection. Fusion-related complications included an iliac crest hematoma and prolonged donor-site pain in one patient. There were no complications related to placement or migration of the cages, but there was one case of screw fracture of the Kaneda device that did not require revision. The authors conclude that anterior lumbar fusion performed using titanium interbody or mesh cages, packed with autologous bone, is an effective, safe method to achieve fusion in a wide variety of pathological conditions of the thoracolumbar spine. The fusion rate of 96% compares favorably with results reported in the literature. The complication rate mirrors the low morbidity rate associated with the anterior approach. A detailed study of clinical outcomes is in progress. Patient selection and strategies for avoiding complication are discussed.