Iliohypogastric Research Articles

Lumbar plexus and its variations

Introduction: Looking to the applied significance of lumbar plexus in the form of its involvement in various injuries, direct or iatrogenic and entrapment, it is imperative to have a thorough knowledge about its formation, branching pattern, and variations. Tubbs et al referred to the lumbar plexus as a ‘no man's land’ because of relative inaccessibility of this region and there is infrequency in operating on retroperitoneal structures by neurosurgeons. However, a recent increase in retroperitoneal laparoscopic surgeries inspired us to revisit the anatomy of lumbar plexus. Material and methods: The study was conducted on 30 formalin embalmed cadavers available in the Department of Anatomy, RMC, PIMS, Loni, Maharashtra. Thorough dissection was performed to observe the formation of branches of lumbar plexus and measurements were taken from the adjacent bony landmarks. Result: Bilateral prefixation of the lumbar plexus was found in one cadaver bilaterally. Ilioinguinal and iliohypogastric nerves were arising by a common stem in 11.66% of cases; in the remaining ones, they were having separate origins. In majority, 81.6% of the genitofemoral nerve pierced the medial third of the anterior surface of the psoas major muscle. Accessory obturator nerve was observed in 3 cases (5%) of 60 plexuses. The site of formation of femoral nerve was 5 cm inferior to the iliac crest in 71.6% of instances. The formation of obturator nerve was found to vary from the level of supracristal plane to 3.5 cm inferior to the plane; in 58.3%, it was 3 cm below the plane. Conclusion: The measurements given in this study will help the surgeon to avoid iatrogenic nerve injury as well as to assess them during lumbar plexus block.

Bilateral Multi-injection Iliohypogastric–Ilioinguinal Nerve Block in Conjunction With Neuraxial Morphine Is Superior to Neuraxial Morphine Alone for Postcesarean Analgesia

Abstract Study Objective To determine whether bilateral iliohypogastric and ilioinguinal (IHII) peripheral nerve blocks, given in conjunction with neuraxial morphine, reduce postcesarean analgesic requirements and side effects, resulting in improved maternal satisfaction. Design Randomized, prospective, double-blinded, placebo-controlled study. Setting Labor and delivery suite at Johns Hopkins Hospital. Patients 34 women scheduled for elective cesarean delivery. Interventions Patients were randomized to receive IHII nerve blocks bilaterally, with either total 24 mL of 0.5% bupivacaine or normal saline, following cesarean delivery via Pfannensteil incision with a standard intrathecal dose of 12 mg of 0.75% bupivacaine with 10 µg of fentanyl and 200 µg of preservative-free morphine. Measurements Patients were assessed at 0, 6, 12, 18, and 24 hours postoperatively. Visual analog scale (VAS) pain scores at rest were recorded at each time period. Analgesic use, patients' perception of nausea, vomiting, pruritus, and their overall satisfaction with their analgesia were recorded for the first 24 hours. Main Results Lower VAS pain scores were seen in the bupivacaine group at 6, 12, 18, and 24 hours postoperatively ( P = 0.01, P P Conclusions Bilateral multilevel injection IHII nerve blocks result in lower resting VAS pain scores, lower analgesic requirements, and greater satisfaction following cesarean delivery in patients who received neuraxial morphine.

Ultrasound-Guided Pain Interventions - A Review of Techniques for Peripheral Nerves

Ultrasound has emerged to become a commonly used modality in the performance of chronic pain interventions. It allows direct visualization of tissue structure while allowing real time guidance of needle placement and medication administration. Ultrasound is a relatively affordable imaging tool and does not subject the practitioner or patient to radiation exposure. This review focuses on the anatomy and sonoanatomy of peripheral non-axial structures commonly involved in chronic pain conditions including the stellate ganglion, suprascapular, ilioinguinal, iliohypogastric, genitofemoral and lateral femoral cutaneous nerves. Additionally, the review discusses ultrasound guided intervention techniques applicable to these structures.

Treatment of inguinal hernia in a difficult environment: feasibility and efficacy of ilioinguinal and iliohypogastric blocks

Hernia repair is a very frequent surgical procedure; it is estimated that one African in five undergoes this procedure during his lifetime. Patients and methods. We evaluated the feasibility of this surgery under ilioinguinal and iliohypogastric nerve blocks in difficult environments. The medical-surgical group supporting Operation Unicorn has treated 48 inguinal hernias as medical aid to population, including 34 with these nerve blocks. Results. The block did not fail in any case. The mean time until discharge was 6.85h, which meant that outpatient surgery was possible. Discussion and conclusion. This type of anesthesia is interesting in difficult environments. It is a safe, inexpensive, and easy to learn technique. These qualities should promote its use in countries with a low GNP.

Surgical treatment of chronic pain after inguinal hernia repair

Chronic groin pain is defined as pain arising 3-6 months after inguinal hernia repair that can compromise the patient's quality of life. Many articles in the literature report clinical presentation, but there are no well-defined indications and protocols of treatment. Forty-six patients underwent surgical treatment for chronic groin pain that consisted of a simultaneous double approach, anterior and posterior, to the inguinal region, with 44 triple neurectomies and 2 iliohypogastric neurectomies. Ilio-inguinal and ilio-hypogastric nerves were resected by anterior approach, while genitofemoral trunk was resected by a posterior pre-peritoneal approach. Mesh was removed in 24 cases, and mesh and plug were removed in 16 cases. A new mesh repair was performed in 42 cases. All the patients were examined 1 week, 1 month and 1 year postoperatively. In 40 patients, the surgical treatment has obtained good response with improvement or complete resolution of the pain. Two patients referred persistent groin pain different from preoperative and in 4 cases the pain persisted without substantial benefit. Mean VAS value was 7.89 before surgery and 1.89 after surgery. Choice of the adequate therapy of chronic groin pain after inguinal hernia repair is still controversial. Our surgical approach turned out to be a safe and effective procedure. In this way, an accurate exploration of the whole inguinal region can be performed along with the identification of the nerves involved. Anyway in a certain number of cases, the resolution of pain cannot be achieved; this suggests a possible involvement of differences in the single personality and tolerances of pain in the different patients.

Bispectral index monitoring of propofol sedation during ultrasound guided nerve block for inguinal herniorraphy: A randomized prospective study.

Background:Patient's awareness can be reduced during ultrasound guided nerve block for inguinal herniorraphy with propofol sedation. The study was aimed to evaluate the clinical efficacy of direct visualization of anatomy of inguinal region by ultrasound and benefits of bispectral index (BIS) monitoring.Materials and Methods:After approval, 40 adult male consented patients of ASA grade I-III of 18-58 years with body mass index <25 were randomized into two groups of 20 patients each. A high frequency (8-13 MHz) linear transducer was used to perform the ilioinguinal and iliohypogastric nerves (ILHN and ILIN) block between the internal oblique and transversus abdominis muscles with 20 mL of 0.75% ropivacaine. The propofol infusion rate for sedation in patients of group I (non-BIS) was managed clinically and in patients of group II (BIS) was managed with BIS index of 65-75. Any surgical or anesthetic complications were recorded. The two groups were compared by evaluating the propofol consumption during surgery.Results:Ultrasonographic visualization of the ILHN and ILIN was possible in all patients and inguinal herniorraphy was performed uneventfully. The mean dose of propofol required for sedation was 5.45 mg/kg/h in patients of group I (non-BIS) while 4.92 mg/kg/h in patients of group II (BIS). The mean propofol consumption was not statistically significant (P = 0.12). All patients were hemodynamically stable and there was no respiratory depression during propofol sedation.Conclusion:Ultrasonography has facilitated the clinically effective nerve block for inguinal herniorraphy and BIS monitoring has ensured amnesia and faster emergence.

Effects of Variable Courses of Inguinal Nerves on Pain in Patients Undergoing Lichtenstein Repair for Inguinal Hernia: Preliminary Results

Background : Problems due to damage to ilioinguinal and iliohypogastric nerves which have many variations following surgery for inguinal hernia cause additional work leave and delay in return to daily life. We aimed to compare outcomes of nerve identification and preservation with a careful dissection during Lichtenstein repair of inguinal hernia between normal courses of inguinal based nerves and variable courses of inguinal based nerves. Methods : This is a prospective study and 116 adult male patients with primary inguinal hernia were operated between December 2009 and June 2010. The patients with a normal nerve trace identified on exploration were assigned into Group Normal Course and those with variable nerve course were assigned into Group Variable Course. These two groups were compared in terms of demographic features, preoperative and postoperative variables, return to work and daily routines, duration of fulfilling personal needs, visual analogue scores before and one and six months after surgery, four-point verbal-rank scale scores, numbness and patient satisfaction.Results : Out of 116 patients, 70 (60.3%) had variable courses of the nerves and were assigned into the Group Variable Course and 46 (39.7%) had normal courses of the nerves and were assigned into Group Normal Course. A single stem for both nerves over spermatic cord (21.6%) and acute infero-lateral angulation of the Ilioinguinal nerve in close contact with and parallel to the Superficial Inguinal Ring fibers at exit (15.5%) were the most observed variations. Duration of surgery was significantly longer in Group Variable Course (p < 0.001). Numbness was also slightly higher in this group one month after surgery. This difference nearly disappeared six months after surgery.Conclusion : Although careful and gentle exploration increases the duration of surgery and early neuropraxia, identification and preservation of nerves during surgery for inguinal hernia help to achieve similar outcomes in both patients with a normal course of nerves and those with a variable course of nerves.

Chronic female pelvic pain

Chronic pelvic pain (CPP) is defined as nonmalignant pain perceived in the structures related to the pelvis that has been present for more than 6 months or a non acute pain mechanism of shorter duration. Pain in the pelvic region can arise from musculoskeletal, gynaecological, urologic, gastrointestinal and or neurologic conditions. Key gynaecological conditions that contribute to CPP include pelvic inflammatory disease (PID), endometriosis, adnexa pathologies (ovarian cysts, ovarian remnant syndrome), uterine pathologies (leiomyoma, adenomyosis) and pelvic girdle pain associated with pregnancy. Several major and minor sexually transmitted diseases (STD) can cause pelvic and vulvar pain. A common painful condition of the urinary system is Interstitial cystitis(IC. A second urologic condition that can lead to development of CPP is urethral syndrome. Irritable bowel syndrome (IBS) is associated with dysmenorrhoea in 60% of cases. Other bowel conditions contributing to pelvic pain include diverticular disease,Crohn's disease ulcerative colitis and chronic appendicitis. Musculoskeletal pathologies that can cause pelvic pain include sacroiliac joint (SIJ) dysfunction, symphysis pubis and sacro-coccygeal joint dysfunction, coccyx injury or malposition and neuropathic structures in the lower thoracic, lumbar and sacral plexus. Prolonged pelvic girdle pain, lasting more than 6 months postpartum is estimated in 3% to 30% of women. Nerve irritation or entrapment as a cause of pelvic pain can be related to injury of the upper lumbar segments giving rise to irritation of the sensory nerves to the ventral trunk or from direct trauma from abdominal incisions or retractors used during abdominal surgical procedures. Afflictions of the iliohypogastric, ilioinguinal, genitofemoral, pudendal and obturator nerves are of greatest concern in patients with pelvic pain. Patient education about the disease and treatment involved is paramount. A knowledge of the differential diagnosis of the pain generators leads to a diagnosis specific management of the pain condition. Using a multidisciplinary approach can improve outcomes for patients suffering from the condition and minimize the associated disability.

Ultrasound guided percutaneous electro-coagulation of ilioinguinal and iliohypogastric nerves for treatment of chronic groin pain

Ultrasound guided percutaneous electro-coagulation of ilioinguinal and iliohypogastric nerves for treatment of chronic groin pain

Revisiting the anatomy of the ilio‐inguinal/iliohypogastric nerve block

The ilio-inguinal/iliohypogastric nerve block (INB) is one of the most common peripheral nerve block techniques in pediatric anesthesia, which is largely due to the introduction of ultrasound (US) guidance. Despite the benefits of US guidance, the absence of an US machine should not deter the provider from performing INB, considering that many institutions, especially in developing countries, cannot afford to provide ultrasound machines in their anesthesiology departments. The aim of this study was to revisit the anatomical position of the ilio-inguinal and iliohypogastric nerves in relation to the anterior superior iliac spine (ASIS), in a large sample of neonatal cadavers, and compare the results with a similar group in a previously published US-guided study. With Ethics Committee approval, the ilio-inguinal and iliohypogastric nerves were carefully dissected in 54 neonatal cadavers. In the total sample, the ilio-inguinal nerve was found to be 2.2±1.2mm from the ASIS, on a line connecting the ASIS to the umbilicus. The iliohypogastric nerve was on average 3.8±1.3mm from the ASIS. For the entire sample, the optimal needle insertion site was 3.00mm from the ASIS. Although there is a strong correlation between the needle insertion point and the weight of the neonate, this will only 'fit' for 60% of the population. The linear regression formula; needle insertion distance (mm)=0.6×weight+1.8 can be used as a guideline for the position of the ilio-inguinal and iliohypogastric nerves.

Ultrasound-guided ilioinguinal/iliohypogastric nerve blocks for chronic pain after inguinal hernia repair

The aim of this study was to evaluate the outcome of ilioinguinal and iliohypogastric nerve blocks in patients with chronic pain after herniorrhaphy, by comparing nerve stimulator and ultrasound guidance to administer the block. A total of 43 patients who received nerve blocks for chronic inguinal post-herniorrhaphy pain received standardized questionnaires. Nerve stimulator-guided blocks were performed prior to January 2009, and thereafter, ultrasound-guided blocks were performed using a local anaesthetic solution and a corticosteroid. The questionnaire was completed by 38 patients (88 %). The inguinal hernia repair was performed for a median 16 months (range 3-219) ahead of the nerve blocks. A median of 2 pain treatments (range 1-7) was calculated. Median follow-up was 21 months (range 3-68). According to the DN4, 21 patients (55.3 %) no longer reported neuropathic pain. Subjectively, 32 % no longer reported moderate-to-severe pain. After ultrasound-guided blocks, a higher VAS score (at rest and during activities), a higher proportion of daily pain and more anxiety and depression are reported compared to blocks performed after nerve stimulator guidance. Ilioinguinal/iliohypogastric nerve blocks can be effective to treat chronic inguinal pain following surgery of the groin. The use of ultrasound was not superior to nerve stimulator-guided blocks. These blocks could be considered prior to more invasive procedures such as neurectomy.

Anatomical feasibility of performing intercostal and ilioinguinal nerve to pelvic nerve transfer: a possible technique to restore lower urinary tract innervation

Nerve transfers are effective for restoring control to paralyzed somatic muscle groups and, recently, even to denervated detrusor muscle in a canine model. A pilot project was performed in cadavers to examine the feasibility of transferring somatic nerves to vesical branches of the pelvic nerve as a method for potentially restoring innervation to control the detrusor muscle in humans. Eleven cadavers were dissected bilaterally to expose intercostal, ilioinguinal, and iliohypogastric nerves, along with vesical branches of the pelvic nerve. Ease of access and ability to transfer the former 3 nerves to the pelvic vesical nerves were assessed, as were nerve cross-sectional areas. The pelvic vesical nerves were accessed at the base of the bladder, inferior to the ureter and accompanied by inferior vesical vessels. The T-11 and T-12 intercostal nerves were too short for transfer to the pelvic vesical nerves without grafting. Ilioinguinal and iliohypogastric nerves (L-1 origin) were identified retroperitoneally and, with full dissection, were easily transferred to the pelvic vesical nerves intraabdominally. The mean cross-sectional area of the dominant pelvic vesical branch was 2.60 ± 0.169 mm(2); ilioinguinal and iliohypogastric branches at the suggested transection site were 2.38 ± 0.32 mm(2) (the means are expressed ± SEM). Use of the ilioinguinal or iliohypogastric nerves for heterotopic transfer to pelvic vesical nerves is surgically feasible, based on anatomical location and cross-sectional areas.

Does nerve identification during open inguinal herniorrhaphy reduce the risk of nerve damage and persistent pain?

Nerve identification during open inguinal hernia herniorrhaphy has been suggested as one of the factors that may reduce the risk of development of persistent postherniorrhaphy pain. In this prospective study, we evaluated whether intraoperative inguinal nerve identification influenced the risk of development of persistent postherniorrhaphy pain, sensory dysfunction in the groin and functional ability score after open hernia repair. A total of 244 men with a primary inguinal hernia underwent open Lichtenstein repair in a high-volume hernia surgery centre, where information on inguinal nerve identification was registered during operation. Before the operation and 6 months postoperatively, functional pain-related impairment was assessed with Activities Assessment Scale and pain intensity scores with Numeric Rating Scale (NRS 0-10). Quantitative sensory testing in the groin was performed before operation and 6 months postoperatively, in order to investigate intraoperative inguinal nerve damage. The intraoperative nerve identification rates for the iliohypogastric, ilioinguinal and genitofemoral nerves were 94.7, 97.5 and 21.3 %, respectively. Thirty-nine patients (16.0 %) had substantial pain-related functional impairment at 6 months follow-up. There was no difference in risk of development of substantial pain-related functional impairment in patients with identification compared with non-identification of the iliohypogastric nerve (P = 1.0), the ilioinguinal nerve (P = 0.59), the genitofemoral nerve (P = 0.40) or all nerves (P = 0.52). There were no differences in regard to sensory loss in the groin area or in regard to improvement in functional outcome following surgery, between patients with and without nerve identification. Although intraoperative inguinal nerve identification should be aimed at, other factors may contribute to the risk of nerve damage and persistent pain after open groin hernia repair.

Normal and sonographic anatomy of selected peripheral nerves. Part III: Peripheral nerves of the lower limb.

The ultrasonographic examination is currently increasingly used in imaging peripheral nerves, serving to supplement the physical examination, electromyography and magnetic resonance imaging. As in the case of other USG imaging studies, the examination of peripheral nerves is non-invasive and well-tolerated by patients. The typical ultrasonographic picture of peripheral nerves as well as the examination technique have been discussed in part I of this article series, following the example of the median nerve. Part II of the series presented the normal anatomy and the technique for examining the peripheral nerves of the upper limb. This part of the article series focuses on the anatomy and technique for examining twelve normal peripheral nerves of the lower extremity: the iliohypogastric and ilioinguinal nerves, the lateral cutaneous nerve of the thigh, the pudendal, sciatic, tibial, sural, medial plantar, lateral plantar, common peroneal, deep peroneal and superficial peroneal nerves. It includes diagrams showing the proper positioning of the sonographic probe, plus USG images of the successively discussed nerves and their surrounding structures. The ultrasonographic appearance of the peripheral nerves in the lower limb is identical to the nerves in the upper limb. However, when imaging the lower extremity, convex probes are more often utilized, to capture deeply-seated nerves. The examination technique, similarly to that used in visualizing the nerves of upper extremity, consists of locating the nerve at a characteristic anatomic reference point and tracking it using the “elevator technique”. All 3 parts of the article series should serve as an introduction to a discussion of peripheral nerve pathologies, which will be presented in subsequent issues of the “Journal of Ultrasonography”.

Morphological structure and variations of lumbar plexus in human fetuses

The objective of this study is to study the anatomy of lumbar plexus on human fetuses and to establish its morphometric characteristics and differences compared with adults. Twenty lumbar plexus of 10 human fetal cadavers in different gestational ages and genders were dissected. Lumbar spinal nerves, ganglions, and peripheral nerves were exposed. Normal anatomical structure and variations of lumbar plexus were investigated and morphometric analyses were performed. The diameters of lumbar spinal nerves increased from L1 to L4. The thickest nerve forming the plexus was femoral nerve, the thinnest was ilioinguinal nerve, the longest nerve through posterior abdominal wall was iliohypogastric nerve, and the shortest nerve was femoral nerve. Each plexus had a single furcal nerve and this arose from L4 nerve in all fetuses. No prefix or postfix plexus variation was observed. In two plexuses, L1 nerve was in the form of a single branch. Also, in two plexuses, genitofemoral nerve arose only from L2 nerve. Accessory obturator nerve was observed in four plexuses. According to these findings, the morphological pattern of the lumbar plexus in the fetus was found to be very similar to the lumbar plexus in adults.

Cough-related neurons in the nucleus tractus solitarius of decerebrate cats

This study was carried out on decerebrate, paralyzed and artificially ventilated cats to investigate the central regulatory mechanism for cough reflex. Fictive cough was induced by repetitive stimulation of the superior laryngeal nerve (SLN) or the nucleus tractus solitarius (NTS), and characterized by an increased inspiratory discharge in the phrenic nerve (stage 1 of cough; S1C) and large burst discharge in the iliohypogastric nerve (stage 2 of cough; S2C). Membrane potential was recorded from the neurons located in the cough-inducible sites of the NTS. Seven augmenting inspiratory (aug-I), 25 inspiratory-modulated (I-mod) and 16 non-respiratory (non-R) neurons were encountered, all of which showed short-latency (7.5±1.6ms, n=48) waves of excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs) in response to single pulse stimulation of the SLN. Out of these, all 7 aug-I and 12 I-mod neurons depolarized during the S1C and hyperpolarized during the S2C (DH-type response). Three I-mod and five non-R neurons showed membrane hyperpolarization during both stages (HH-type response). Ten I-mod and three non-R neurons displayed membrane depolarization during the S1C and S2C (DD-type response). The remaining eight non-R neurons showed no response during the fictive cough (NN-type response) but a long-lasting EPSP wave to single SLN stimulation. The NTS neurons recorded here were divided into three groups. Group I neurons with the NN-type response may be the second-order relay neurons. Group II neurons with the DD-type response may integrate the tussigenic afferent information and send a gate signal to the cough pattern generator. Group III neurons with either DH-type or HH-type response may constitute the network of cough pattern generation or modulatory circuits recruited during the cough reflex. The present study suggests that Group II neurons may play a gating role in generating the cough reflex.

Bilateral multi-injection iliohypogastric-ilioinguinal nerve block in conjunction with neuraxial morphine is superior to neuraxial morphine alone for postcesarean analgesia

Study ObjectiveTo determine whether bilateral iliohypogastric and ilioinguinal (IHII) peripheral nerve blocks, given in conjunction with neuraxial morphine, reduce postcesarean analgesic requirements and side effects, resulting in improved maternal satisfaction. DesignRandomized, prospective, double-blinded, placebo-controlled study. SettingLabor and delivery suite at Johns Hopkins Hospital. Patients34 women scheduled for elective cesarean delivery. InterventionsPatients were randomized to receive IHII nerve blocks bilaterally, with either total 24 mL of 0.5% bupivacaine or normal saline, following cesarean delivery via Pfannensteil incision with a standard intrathecal dose of 12 mg of 0.75% bupivacaine with 10 µg of fentanyl and 200 µg of preservative-free morphine. MeasurementsPatients were assessed at 0, 6, 12, 18, and 24 hours postoperatively. Visual analog scale (VAS) pain scores at rest were recorded at each time period. Analgesic use, patients’ perception of nausea, vomiting, pruritus, and their overall satisfaction with their analgesia were recorded for the first 24 hours. Main ResultsLower VAS pain scores were seen in the bupivacaine group at 6, 12, 18, and 24 hours postoperatively (P = 0.01, P < 0.01, 0.02, and 0.04, respectively). A longer mean time to first rescue dose of ketorolac was noted in the bupivacaine group (14.3 ± 1.8 hrs) than the saline group (mean 5.6 ±1.1 hrs), (P < 0.01). Fewer patients in the bupivacaine group made requests for acetaminophen 500 mg/oxycodone 5 mg in the first 24 hours. Satisfaction was greater in the bupivacaine group. No difference in side effects was noted between groups. ConclusionsBilateral multilevel injection IHII nerve blocks result in lower resting VAS pain scores, lower analgesic requirements, and greater satisfaction following cesarean delivery in patients who received neuraxial morphine.

Radiofrequency Neurolysis Versus Local Nerve Infiltration in 42 Patients with Refractory Chronic Inguinal Neuralgia

Background: Chronic inguinal neuralgia involving ilioinguinal and iliohypogastric nerves is a frequent complication of surgical procedures involving a lower abdominal incision such as hernia repair, appendicitis surgery, or cesarean sections. Chronic inguinal neuralgia is a very painful condition and diagnosis can be challenging as it is an overlooked impairment. Existing specific treatments are inefficient and often fail. Objective: The purposes of this study are to describe, evaluate, and compare ilioinguinal and iliohypogastric radiofrequency neurolysis (RFN) and local injection. Study Design: Retrospective comparison cohort study from 2005 to 2011. Setting: A single center, Academic Interventional Pain Management Unit Methods: Forty-two patients suffering from chronic inguinal pain refractory to specific medication were included. A total of 18 RFN procedures (14 patients) and 28 injections (28 patients) were performed. Pain was assessed in both groups using Visual Analog Scale (VAS) scores (0-10) measured immediately before and after the procedure and at one, 3, 6, 9, and 12 months after the procedure. Mean duration of pain prior to the procedure and mean duration of pain relief were noted. Moreover, mean maximum early pain relief was assessed. All procedures were ambulatory under computed tomography (CT) guidance. Injections contained 1.5 mL of cortivazol and 3 mL of lidocaine-ropivacaine (30%-70%). Radiofrequency neurolysis was performed using a Neurotherm RF Generator. In both cases, 22-gauge needles were used. After needle retrieval, control slices were taken and the patient was supervised for 30 minutes at the CT unit. Results: The mean age in both groups was 48.7 years. Forty-two patients (97.6%) presented postsurgical inguinal pain, 62% of which occurred after hernia repair. All included patients had undergone previously unsuccessful pain therapies. Mean VAS scores were 7.72 in the RF group and 7.46 in the infiltration group. Maximum early pain relief did not statistically differ (77% in the RFN group and 81.5% in the injection group). Mean duration of pain relief was statistically significant (P = .005) in the RF group (12.5 months) compared to the infilitration group (1.6 months). Mean VAS scores during the year following the procedure were all significantly in favor of radiofrequency neurolysis management. Limitations: Those inherent to small study samples and retrospective studies. Conclusion: Radiofrequency neurolysis appears to be significantly more effective than local nerve infiltrations. It is a safe and effective treatment for chronic inguinal pain. Local steroid injection along with local injection of anesthetics should be used as a confirmation of ilioinguinal neuropathy before performing radiofrequency neurolysis. Key words: Radiofrequency, Ilioinguinal, Iliohypogastric, neuropathy, infiltration, computed tomography guidance.

Anterior Pelvic Subcutaneous Internal Fixator Application

To determine what anatomic structures are at risk after the application of a subcutaneous anterior pelvic internal fixator (APIF), from an incision over the anterior iliac crest to an incision centered over the pubic symphysis (Pfannenstiel). A laboratory investigation was performed using 5 fresh, frozen, nonpreserved cadaveric specimens (3 male specimens, 2 female specimens). Dissections were carried out to identify the relationships and proximity between the fixator screw constructs and various anatomic structures, including the (1) lateral femoral cutaneous nerve (LFCN), (2) ilioinguinal nerve (IIN), (3) iliohypogastric nerve (IHN), (4) femoral nerve, (5) femoral artery, (6) femoral vein, (7) genitofemoral nerve; and (8) spermatic cord or round ligament. The mean and range of distance from each of these structures to the implant were measured with calipers. Despite variations in pelvic anatomy and width of pelvic brims, precontoured fixators (3.5 locking reconstruction plates) did not violate any pelvic neurovascular structures using this recommended application of an APIF. The spermatic cord was easily avoided as they were directly visualized using our application technique (mean, 0.4 cm, range, 0-2 cm). Abdominal musculature protected the IHN and IIN for most of their course, with the precontoured plates remaining inferior to their course and resting superficial to their branches (IHN mean, 1.5 cm, range, 1.2-1.8 cm and IIN mean, 2.1 cm, range, 0.9-4 cm). The LFCN traveled safely posterior to the inguinal ligament, thus being bridged by the internal spanning fixation without visualized disruption, impingement, or violation (mean, 1.5 cm, range, 0.6-4 cm). Finally, the femoral nerve, artery, and vein collectively demonstrated safe distance from the risk of compression (mean, 2.2 cm, range, 0.8-3.7 cm). The anatomic structures hypothesized to be potentially endangered because of the lack of direct visualization during APIF placement, include the LFCN, IIN, IHN, femoral nerve, femoral artery, and femoral vein. Based upon our anatomic study, APIF, which may be used for treatment augmentation of anterior pelvic ring disruptions, does not place these structures at significant risk. In addition, the reproductive structures (round ligament and spermatic cord) are in direct visualization and can easily be avoided during implant placement.

Application of ultrasound guidance for ilioinguinal or iliohypogastric nerve block in pediatric inguinal surgery

To evaluate the efficacy of ultrasound guidance for ilioinguinal or iliohypogastric nerve block in pediatric outpatients undergoing inguinal surgery. The present study was approved by the ethics committee of our hospital. One hundred children with ASA status I, aged 4 - 8 years old, scheduled for unilateral inguinal surgery were randomly divided into ultrasound group (Group U) and traditional group (Group T) (n = 50 each). Upon entering operation room, they were monitored by electrocardiography (ECG), heart rate (HR) and oxygen saturation (SpO(2)). After an induction of general anesthesia, intravenous access was established and laryngeal mask inserted with spontaneous breathing. Intraoperative anesthesia was maintained with 2% sevoflurane in 50% nitrous oxide with 50% oxygen. Children in Group U received an ilioinguinal or iliohypogastric block under ultrasonic guidance with a mixture of 0.8% lidocaine and 0.25% levobupivacaine at 0.2 ml/kg while those in Group T performed according to the traditional method of anatomical localization with the same local anesthetic at 0.3 ml/kg. During surgery, the vital signs of HR, respiratory rate (RR), SpO(2), partial pressure of end-tidal carbon dioxide (P(ET)CO(2)) and exhaled sevoflurane concentration were recorded. Additional intraoperative analgesic requirements were recorded. Face legs activity cry consolability (FLACC) score was used to assess the pain score postoperatively at recovery time, 2 and 4 h postoperation respectively. If the pain score was above 3, the child received acetaminophen rectally. The number of postoperative rectal acetaminophen was recorded. The degrees of parental satisfaction were investigated at 2 and 4 h postoperation. Intra-or postoperative adverse events were also recorded. HR at skin incision and sac traction in Group U was significantly lower than those in Group T (P < 0.05). Six children (12%) needed to increase inhaled sevoflurane concentration during operation in Group U versus 17 (34%) in Group T (P < 0.05). The pain score at recovery time, 2 and 4 h postoperation in Group U was significantly lower than those in T group (P < 0.05). Only 4 children (8%) needed postoperative rectal acetaminophen in Group U versus 13 (26%) in Group T (P < 0.05). The degree of parental satisfaction at 2 h postoperation was significantly higher in Group U than that in Group T (P < 0.05). One case in Group T had needle puncturing into blood vessels. No other adverse event was observed in two groups. The method of ultrasonic guidance for ilioinguinal or iliohypogastric nerve block is both feasible and effective. It can not only enhance the effect of nerve block, reduce the occurrences of complications, lower the quantity of local anesthetic and alleviate the medicinal toxicity.