Ultrasound-guided combined femoral nerve and lateral femoral cutaneous nerve blocks for femur neck fracture surgery--case report

We report two cases of elderly patients who underwent ultrasound-guided combined femoral nerve and lateral femoral cutaneous nerve blocks for osteosynthesis of femur neck fracture. In both cases, neuraxial anesthesia was contraindicated due to coagulopathy, and severe restrictive ventilatory disorder was observed. The femoral nerve and lateral femoral cutaneous nerve blocks were performed with 20ml of 0.375% ropivacaine under ultrasonographic visualization using a high frequency linear probe. Ultrasonographic visualization was useful to identify the needle tip and to observe the spread of local anesthetics. Supplemental local infiltration of anesthetics and intravenous low-dose sedative drugs were administered during surgery. The perioperative course was uneventful in both cases. This combined block technique could be a choice for osteosynthesis of femur neck fracture especially in high-risk patients.     

Comparison of the fascia iliaca compartment block with the 3-in-1 block in children

A new single injection procedure, the fascia iliaca compartment block, is described for blocking the femoral, lateral cutaneous, and obturator nerves. The technique consists of injecting a local anesthetic immediately behind the fascia iliaca at the union of the lateral with the two medial thirds of the inguinal ligament, and forcing it upward by finger compression. This block was prospectively evaluated in 60 pediatric patients aged 0.7 to 17 years undergoing surgery of the lower limb, and then compared with a similar group of 60 children given a 3-in-1 block. Adequate analgesia was only obtained in 20% of the patients given 3-in-1 blocks (group 1), whereas the fascia iliaca compartment block proved to be easy, free of complications, and effective in more than 90% of patients (group 2). Such a high failure rate in group 1 was not due to misplacement of the needle since a femoral nerve block developed in all patients. Therefore it is unlikely that the local anesthetic can spread rostrally towards the lumbar plexus then return peripherally along the issuing nerves, and this was, indeed, not confirmed by radiological findings. In the authors' opinion, a multieffective block can only develop when the local anesthetic is introduced behind the fascia iliaca, which circumscribes a potential space where the femoral, lateral cutaneous, and obturator nerves run for a considerable part of their course. This report shows that deliberately injecting this space almost always results in an easy and effective block of these three nerves. The fascia iliaca compartment block can be recommended for use in children.     

Lateral femoral cutaneous nerve: an anatomic study

The purpose of our study was to determine the location of the lateral femoral cutaneous nerve and its branches at the inguinal ligament and proximal thigh. We think that further defining the location of the nerve and its branches based on certain measurements from known anatomic landmarks would enable us to determine a danger zone that could aid in preventing iatrogenic injury to the lateral femoral cutaneous nerve. The anatomic course of the lateral femoral cutaneous nerve was studied in 29 cadaver specimens and distances from various landmarks were recorded. In addition, the branching pattern of the nerves was recorded. We observed variability in the course and branching patterns of the lateral femoral cutaneous nerve. The lateral femoral cutaneous nerve was found to potentially be at risk as far as 7.3 cm medial to the anterior superior iliac spine along the inguinal ligament and as much as 11.3 cm distal on the sartorius muscle from the anterior superior iliac spine. As many as five branches of the lateral femoral cutaneous nerve were found and in 27.6% of cases the lateral femoral cutaneous nerve branched before traversing the inguinal ligament. We used this information to describe a danger zone, which could be used as a guide to help prevent unnecessary injury during certain procedures.     

Case Report: Meralgia Paresthetica in a Baseball Pitcher

We report a case of meralgia paresthetica occurring in an amateur baseball pitcher who experienced inguinal pain and dysesthesia in the anterolateral thigh during pitching practice. The lateral femoral cutaneous nerve was pushed up by the iliac muscle to the inguinal ligament at the sharp ridge of its fascia and ensheathed in the tendinous origin of the sartorius muscle. Neurolysis of the lateral femoral cutaneous nerve and partial dissection of the inguinal ligament and sartorius muscle promptly relieved the symptoms and the patient resumed pitching 1 month later. These anatomic variations of the lateral femoral cutaneous nerve in the inguinal region might render the nerve susceptible to compression and irritation, and repetitive contraction of inguinal muscles during throwing motion might induce and exacerbate the neuropathy of the lateral femoral cutaneous nerve. Each author certifies that he has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his institution has approved the reporting of these case reports, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.     

Transient femoral nerve palsy following ilio-inguinal nerve blockade for day case inguinal hernia repair

BACKGROUND: Transient femoral nerve palsy (TFNP) has been reported in patients undergoing inguinal hernia repair involving the use of ilio-inguinal nerve block. Ilio-inguinal nerve blocks can be administered under vision by the surgeon or by the anaesthetist using a standard blind technique. There has been no study that has specifically examined the incidence of this complication and whether its development is related to the type of method used to administer the block. PATIENTS AND METHODS: Data on patients undergoing surgery in the Royal Infirmary Edinburgh Day Case Unit are collected prospectively. All patients who undergo inguinal hernia repair are given ilio-inguinal field blocks, either pre-operatively by anaesthetists (blind technique) or peri-operatively under direct vision by surgeons. Several cases of TFNP were initially identified during the process of surgical audit and this led to a retrospective analysis over a period of one year. RESULTS: During a 12-month period, 194 patients underwent 200 open inguinal hernia repairs (188 unilateral and 6 bilateral), under general anaesthesia. Ten patients (5%) developed TFNP resulting in overnight admission. Surgeons administered 101 blocks under direct vision of which 4 (4%) resulted in TFNP, whereas 6 out of 99 (6%) blind blocks resulted in TFNP (p=0.49, df=1, Chi2 test). DISCUSSION AND CONCLUSION: TFNP is a recognised complication following ilioinguinal nerve blockade for inguinal hernia surgery. Our series shows that ilio-inguinal block given under direct vision does not appear to reduce the chance of this complication occurring. This may result from the fact that this complication could be due to local infiltration into the operative field rather than direct infiltration around the femoral nerve. As inguinal hernia repair undertaken as a day case procedure increases, the awareness of this complication is important to avoid morbidity     

Documenting neuropathy of the lateral femoral cutaneous nerve using the Pressure-Specified Sensory Testing device

Entrapment of the lateral femoral cutaneous nerve has been difficult to document. The variability of the anatomic location of this nerve makes it difficult to measure with traditional electrodiagnostic studies. At the same time, anatomic variability increases the likelihood for this nerve to become entrapped within the inguinal ligament. The current study reports the ability to document the presence of this nerve entrapment in 24 patients, compared with 10 asymptomatic control subjects, by using nonpainful and noninvasive computer-assisted neurosensory testing with the Pressure-Specified Sensory Device.     

Comparison of 4 techniques for internal saphenous nerve block

OBJECTIVE: To assess the efficacy of 4 techniques for internal saphenous nerve block with 10 mL of 1.5% mepivacaine. METHODS: Eighty ASA I-II patients scheduled for foot (hallux valgus) surgery with combined sciatic and saphenous nerve blocks were randomized to receive the saphenous nerve block by one of the following techniques: a paravenous approach (n = 20), a transsartorial approach (n = 20), a femoral nerve approach in the inguinal region using a nerve stimulator (n = 20), and by subcutaneous infiltration between the tibial tuberosity and the internal gastrocnemius muscle (n = 20). A pressure cuff was placed 10 cm below the knee of all patients. Success was assessed by pin prick inside the ankle 30 minutes after initiation of the block. Tolerance of the pressure cuff and discomfort during performance of the technique were also assessed. RESULTS: The 4 groups were similar as to distribution of males and females and mean weight, age, and height. Blocking the saphenous nerve by way of the femoral nerve in the inguinal region was the most effective approach (success in 95% of patients), significantly better than the other 3 techniques (P < 0.05). The paravenous approach was successful in 60% of cases, the transsartorial approach in 50%, and the subcutaneous infiltration technique in 45%. The pressure cuff was well tolerated by all patients (100%) in whom the femoral nerve approach was used. The cuff was tolerated by 70% in the paravenous approach group, by 65% in the transsartorial approach group, and by 60% in the subcutaneous infiltration group. Patients reported more discomfort during initiation of the blockade in the paravenous approach and subcutaneous infiltration groups than in the femoral nerve or transsartorial approach groups (P < 0.05). CONCLUSION: The femoral nerve approach in the inguinal region, with nerve stimulator, to block the internal saphenous nerve led to a larger number of successful blocks than did the paravenous or transsartorial approaches, or the technique of subcutaneous infiltration between the tibial tuberosity and internal gastrocnemius muscle.     

Magnetic resonance imaging of the distribution of local anesthetic during the three-in-one block

The three-in-one technique of simultaneously blocking the femoral, the lateral femoral cutaneous (LFC), and the obturator nerves by a single injection of a local anesthetic was first described in 1973, and it was suggested that the underlying mechanism was one of cephalad spread resulting in a blockade of the lumbar plexus. Today, the technique is widely used in surgery and pain management of the lower limb. Many investigators have, however, reported suboptimal analgesia levels, particularly in the obturator nerve. The purpose of this prospective study was to trace the distribution of a local anesthetic during a three-in-one block by means of magnetic resonance imaging (MRI). Seven patients scheduled for surgery of the lower limb were analyzed with the aid of a primary MRI and then received three-in-one blocks using 30 mL of bupivacaine 0.5% under the guidance of a nerve stimulator. A secondary MRI was performed to determine the distribution pattern of the local anesthetic. It emerged that the local anesthetic blocks the femoral nerve directly, the LFC nerve through lateral spread, and the anterior branch of the obturator nerve by slightly spreading in a medial direction. No involvement of the proximal and posterior portions of the obturator nerve was observed, nor was there any cephalad spread that could have resulted in a lumbar plexus blockade. We therefore conclude that the basis of the three-in-one block is confined to lateral, medial, and caudal spread of the local anesthetic, which effectively blocks the femoral and LFC nerves, as well as the distal anterior branch of the obturator nerve. IMPLICATIONS: We demonstrate by using magnetic resonance imaging that the mechanism of a three-in-one block is one of lateral, caudal, and slight medial spread of a local anesthetic with subsequent blockade of the femoral, the lateral femoral cutaneous, and the anterior branch of the obturator nerves. It does not involve cephalad spread of the local anesthetic with blockade of the lumbar plexus.     

A review of approaches and techniques for lower extremity nerve blocks

PURPOSE: The purpose of this narrative review is to summarize the evidence derived from randomized controlled trials (RCTs) regarding approaches and techniques for lower extremity nerve blocks. SOURCE: Using the MEDLINE (January 1966 to April 2007) and EMBASE (January 1980 to April 2007) databases, medical subject heading (MeSH) terms "lumbosacral plexus", "femoral nerve", "obturator nerve", "saphenous nerve", "sciatic nerve", "peroneal nerve" and "tibial nerve" were searched and combined with the MESH term "nerve block" using the operator "and". Keywords "lumbar plexus", "psoas compartment", "psoas sheath", "sacral plexus", "fascia iliaca", "three-in-one", "3-in-1", "lateral femoral cutaneous", "posterior femoral cutaneous", "ankle" and "ankle block" were also queried and combined with the MESH term "nerve block". The search was limited to RCTs involving human subjects and published in the English language. Forty-six RCTs were identified. PRINCIPAL FINDINGS: Compared to its anterior counterpart (3-in-1 block), the posterior approach to the lumbar plexus is more reliable when anesthesia of the obturator nerve is required. The fascia iliaca compartment block may also represent a better alternative than the 3-in-1 block because of improved efficacy and efficiency (quicker performance time, lower cost). For blockade of the sciatic nerve, the classic transgluteal approach constitutes a reliable method. Due to a potentially shorter time for sciatic nerve electrolocation and catheter placement than for the transgluteal approach, the subgluteal approach should also be considered. Compared to electrolocation of the peroneal nerve, electrostimulation of the tibial nerve may offer a higher success rate especially with the transgluteal and lateral popliteal approaches. Furthermore, when performing sciatic and femoral blocks with low volumes of local anesthetics, a multiple-injection technique should be used. CONCLUSIONS: Published reports of RCTs provide evidence to formulate limited recommendations regarding optimal approaches and techniques for lower limb anesthesia. Further well-designed and meticulously executed RCTs are warranted, particularly in light of new techniques involving ultrasonographic guidance.     

Bloc ≪ 3 en 1 ≫ ou bloc femoral. Que faut-il faire et comment le faire ?

The “3 in 1” block and the femoral nerve block are widely used for lower limb surgery and postoperative analgesia. Whether these blocks are in fact a same regional block with two different names or represent definitively two different blocks remains controversial. A large number of anatomical as well as functional variations of the lumbar plexus have been described and complicate a rational analysis of the spread of local anaesthetics following these blocks. Anatomical, radiological and especially clinical data seem to confirm that these blocks are to be distinguished from one another. Femoral nerve block requires the use of a nerve stimulator and has a high success rate in the territory of the femoral nerve; a spread towards other lumbar nerves, especially the lateral femoral cutaneous nerve, is sometimes observed. The “3 in 1” block is supported by the idea of diffusion within a space that is located after going through two fascial layers. Even in experienced hands, the success predictive value is not high. However, once the “3 in 1” block is well performed, a complete anaesthesia covering the territories of the femoral nerve, the lateral femoral cutaneous nerve, and the obturator nerve occurs. Specific indications of each technique are different: major knee surgery and postoperative analgesia for the “3-in-1” block and leg surgery for femoral nerve block. The best approach for knee arthroscopy remains open for discussion.     

Idiopathic meralgia paresthetica

Idiopathic meralgia paresthetica was treated surgically in 14 men and 11 women, the latter group were a decade older on average. Treatment was unsatisfactory if symptoms had been present for longer than 18 months. Reexploration of the nerve was not therapeutic in those cases in which the initial decompression provided no relief. The usual course of the lateral femoral cutaneous nerve is deep to the lateral end of the inguinal ligament but superficial to the sartorius muscle. However, the nerve may overlie the anterior iliac wing or pass between two slips of the inguinal ligament and may also be compressed if it passes deep to or through the sartorius muscle.     

Abordaje ecoguiado a nivel antecubital para cirugía del síndrome del túnel del carpo

IntroductionThere are various anaesthetic techniques for ambulatory surgery of carpal tunnel release. The ultrasound-guided nerve blocks offer advantages compared to other techniques. The purpose of this study was to evaluate the efficacy using ultrasound-guided block at the antecubital fossa, as well as to evaluate complications, patient satisfaction and surgeon satisfaction with the block.Materials and methodsProspective observational study with 32 elective patients for carpal tunnel release in a one-day case unit. An ultrasound-guided block with mepivacaine 1% was performed at the antecubital fossa, aiming for the median, ulnar and the lateral and medial cutaneous nerves of the forearm. The measurements of the anteroposterior and laterolateral diameters of the median and ulnar nerves were recorded, before and after injection. Motor and sensory levels were evaluated for the median and ulnar nerves at 5 and 30 min post injection, and compared with the contralateral hand. Pain from the surgical incision time and recovery were recorded, together with complications, and patient and surgeon satisfaction with the block.ResultsThe antecubital fossa ultrasound-guided block was successful in 93.7% of the patients. No patients needed rescue analgesia in recovery and no complications were recorded. Patient satisfaction was 93.7% and surgeon satisfaction was 97%.ConclusionsA selective block of the medial, ulnar and medial and lateral cutaneous nerves of the forearm are effective and satisfactory anaesthetic techniques for carpal tunnel release in a one-day case unit. It allows early mobilization, minimises risks and amount of local anaesthetic used.     

Peripheral nerve blocks for a patient with spondylolysis undergoing anterior cruciate ligament reconstruction

A 24-year-old man, 178 cm tall and weighting 82 kg, underwent anterior cruciate ligament reconstruction. We gave general anesthesia and ultrasound-guided combined femoral and sciatic nerve block. Neuraxial blocks increase the risk of neuropathy in the patient with spondylolysis compared with peripheral nerve blocks. In this report, we describe the successful postoperative pain control with peripheral nerve blocks to a patient with spondylolysis.     

Regional anesthesia in knee arthroscopy: A new technique involving femoral and sciatic nerve blocks in knee arthroscopy

We describe a new anesthetic technique of femoral and sciatic nerve blocks in knee arthroscopy. The sciatic nerve block is administered through a posterior approach, and the block of the femoral and lateral femoral cutaneous nerves in a single anterior approach. This type of regional anesthesia is safe and effective, providing excellent intraoperative and postoperative analgesia as well as minimizing postoperative complications.     

Compression of the lateral femoral cutaneous nerve by a fibrous sartorius strand in a professional female soccer player

Meralgia paraesthetica represents a neuropathy involving pain, burning, tingling, and numbness in the distribution of the lateral femoral cutaneous nerve (LFCN) of the thigh, which is commonly due to nerve entrapment under the inguinal ligament. We report an unusual case of compression of the LFCN at the anterior surface of the sartorius muscle in a professional female soccer player. Intraoperatively, the LCFN was found to pass without major compression under the inguinal ligament, but was strained over a fibrous thickening of the superficial thigh fascia and the anterior medial border of the sartorius muscle 8 cm caudal of the inguinal ligament. Excision of the fibrous tissue completely resolved the symptoms. In professional athletes, the LFCN should be explored along its entire course on the anterior thigh during operative decompression to rule out a distal muscular compression site. Level of evidence: Level V, therapeutic study     

神经刺激器指导实施下肢神经联合阻滞的麻醉效果

目的比较在神经刺激器指导下实施不同下肢神经联合阻滞的麻醉效果。方法选择ASAⅠ或Ⅱ级18~58岁股骨下段以下的下肢手术患者80例,随机均分为:坐骨神经加股神经阻滞组(N1组)、坐骨神经加股神经加股外侧皮神经阻滞组(N2组)、坐骨神经加腰大肌肌间沟阻滞组(N3组)与脊麻组(S组)。用不同电流强度刺激指导穿刺,比较神经阻滞的起效和持续时间、阻滞的效果以及患者满意度评分和不良反应。结果N2、N3组止血带反应明显轻于N1与S组。N1、N2和N3组的感觉与运动阻滞时间均明显长于S组(P<0.01)。电流的强度与起效时间呈正相关。结论神经刺激器电流强度在0.25~0.30mA时麻醉效果满意。坐骨神经加股神经加股外侧皮神经阻滞和坐骨神经腰大肌肌间沟阻滞用于股骨下段以下的下肢手术是一种安全可靠的麻醉方法,坐骨神经加股神经阻滞适用于股骨下段以下短小手术,效果可靠。     

A new rule for femoral nerve blocks

BACKGROUND AND OBJECTIVES: Acupuncture points are described by use of a proportional system that is based on the width of the thumb at the level of the distal interphalangeal joint, defined as 1 CUN. Our study tested first the correlation between the CUN and weight and height in 500 Americans and second the hypothesis that the CUN system is superior to the conventional landmarks to localize the femoral nerve 1 or 2 cm lateral to the artery in a prospective, double-blinded, randomized study. METHODS: Sixty-two patients were randomized to receive a femoral nerve block by a needle entry point either 1 CUN lateral, 1 cm lateral, or 2 cm lateral to the femoral artery at the level of the inguinal crease. The time from needle entry to injection of local anesthetic was measured by an investigator blind to the technique, who also counted the frequency of needle repositioning, graded the ease of the block and its success, and registered complications. RESULTS: Good correlation occurred between weight and CUN (r = 0.79) and height and CUN (r = 0.83), which indicates that the CUN of a normal person (predefined as 175 cm tall and 70 kg weight) is 18.7 +/- 1 mm. In the CUN group, the femoral block was achieved significantly faster (P < .01) with fewer attempts (P < .003). The success rate was the same and complications did not differ significantly between the groups. CONCLUSION: A needle insertion point 1 CUN lateral to the midpoint of the palpated femoral artery at the level of the inguinal crease makes femoral nerve blocks faster and easier compared with conventional landmark 1 cm to 2 cm lateral to the artery.     

The cutaneous nerves encountered during laparoscopic repair of inguinal hernia

BACKGROUND: With an incidence rate of 2%, injury to the nerves of the lumbar plexus is the most common complication of laparoscopic hernioplasty, particularly when the transabdominal preperitoneal (TAPP) technique is used. METHODS: The course of the genitofemoral nerve, lateral femoral cutaneous nerve, and ilioinguinal nerve within the operation site was investigated in 53 adult dissecting-room bodies. Their relationship to the deep inguinal ring, iliopubic tract, and anterior superior iliac spine was also examined. RESULTS: Both the femoral and genital branches of the genitofemoral nerve may penetrate the abdominal wall lateral to the deep ring and cranial to the iliopubic tract. The lateral femoral cutaneous nerve and the ilioinguinal nerve may run immediately lateral to the anterior superior iliac spine. CONCLUSION: Contrary to the previously accepted opinion, dissection and the placement of staples either cranial to the iliopubic tract or lateral to the anterior superior iliac spine can result in injury to the nerves.