Inflammatory Myofibroblastic Tumor of the Sciatic Nerve Mimicking Lumbar Disc Herniation: A Diagnostic Challenge.

Inflammatory myofibroblastic tumors (IMTs), which involve the proliferation of fibroblastic-myofibroblastic cells mixed with inflammatory infiltrates, are exceedingly rare in the extremities. There are no reported IMTs involving the sciatic nerve. This type of involvement may cause entrapment of the sciatic nerve, whose symptoms may mimic lumbar disc herniation (LDH), especially when it occurs in patients with lumbar degenerative disc disease. We describe the case of a 40-year-old male with lumbar degenerative disc disease accompanied by IMT involving the sciatic nerve whose symptoms mimicked LDH and posed a diagnostic challenge. We showed the course of the disease as well as the systematic imaging manifestations of IMTs involving the sciatic nerve and discussed their therapeutic management.

The anatomy of the motor branches of the sciatic nerve: an anatomical study with clinical implications.

BACKGROUND: The sciatic nerve gave the motor branches supply to: biceps femoris long and short head, semitendinosus, semimembranosus and adductor magnus muscles. The anatomy of these motor branches is highly variable. The aim of this study was to estimate the anatomy and morphometry of hamstring muscles innervation. MATERIALS AND METHODS: The motor branches of the sciatic nerve were dissected from both sides from 20 cadaveric specimens (9 left and 11 right) from the 11 cadavers (4 females and 7 males) at the Department of Anatomy, Jagiellonian University Medical College Cracow. RESULTS: The motor branches of the sciatic nerve length, distance from piriformis muscle and number of all branches that exist from tibial nerve and common fibular nerve were measured. In most cases common fibular nerve gave off one branch to the short head of biceps femoris, in most cases the proximal hamstring tendon was innervated only by the first trunk, the highest number of branches were innervating the semimembranosus and the long head of biceps femoris, the longest branches were coming to the semimembranosus and the shortest to the proximal hamstring tendon CONCLUSIONS: The present study shows that there are various innervation types of the posterior group of thigh muscles. Knowledge of possible innervation patterns could be of utmost value to operators performing surgeries on the posterior region of the thigh.

Investigation of the effectiveness of atmospheric pressure cold plasma on sciatic nerve injury in rats.

BACKGROUND: The aim of this study was to evaluate the efficacy of atmospheric pressure cold plasma jet and plasma activated medium (PAM) on sciatic nerve injury (SNI). MATERIALS AND METHODS: Rats were divided into 6 groups (n = 10); group 1 (Sham), group 2 (SNI), group 3 (SNI + Atmospheric pressure cold plasma jet 5 min), group 4 (SNI + Atmospheric pressure cold plasma jet 10 min), group 5 (SNI + PAM 5 min), group 6 (SNI + PAM 10 min). On the 1st, 8th, 15th, 22nd days of the study, atmospheric pressure cold plasma jet was applied to rats in groups 3 and 4, and PAM was applied to rats in groups 5 and 6. Hot plate test was applied to all rats on the same days. On day 28, the experiment was terminated and sciatic nerve tissues were removed for histopathologic evaluations. RESULTS: According to the 4-week average of the hot plate tests, a significant relationship was found between group 2 and group 4 and group 6 (p < 0.05). When evaluated within each week, significant differences were found between group 2 and group 4 in week 1, between group 2 and group 5 and group 6 in week 2, between group 2 and group 4 in week 3, and between group 2 and group 4 and group 6 in week 4 (p < 0.05). As a result of histopathologic analysis, except for the control group, the other groups had similar characteristics in terms of axonal degeneration, periaxonal swelling and axon density. CONCLUSIONS: As a result of our study, we found that plasma application showed an improvement in the duration of the hot plate test, but did not show any improvement histopathologically.

Combined Lumbar Plexus-Sciatic Nerve Block for Urgent Lower Limb Surgery: A Good Alternative in Patients With High Anesthetic Risk.

The use of peripheral nerve blocks has grown significantly in recent years not only because of the progress and availability of the materials necessary for its realization but also for enhancing patient safety. Anesthesia in the elderly or individuals with high anesthetic risk is always a challenge for the practitioner. Hence, the importance of peripheral nerve blocks in avoiding the side effects associated with general or spinal anesthesia. In this report, we present a case series of five patients with high anesthetic risk (classified American Society of Anesthesiologists (ASA) III or IV) who underwent different lower limb surgeries under a combined lumbar plexus-sciatic nerve block. The goal of this case series was to evaluate the effectiveness of this technique as an anesthetic alternative for these different types of surgical procedures.

Local compression of the sciatic nerve by a vascular malformation as a rare cause of sciatica: A case report and review of literature.

Background: Sciatica is typically caused by disc herniations or spinal stenosis. Extraspinal compression of the sciatic nerve is less frequent. Case Description: We report a rare case of sciatica with compression of the sciatic nerve by a low-flow vascular malformation in a 24-year-old female patient. The special feature of this case was sciatica along the S1 dermatome, which only occurred in the sitting position and inclination because of compression of the sciatic nerve between the vascular malformation and the lesser trochanter. Spinal imaging showed no abnormal findings. Surgery was performed interdisciplinary and included neurosurgery, vascular surgery, and trauma surgery. After surgery, the patient became symptom-free. Conclusion: Rare and extraspinal causes of local compression of the sciatic nerve should be considered, especially in cases of lacking spinal imaging correlation and untypical clinical presentation. Interdisciplinary surgical cooperation is of special value in cases of rare entities and uncommon locations.

A Case Report of an Ultrasound-Guided Popliteal Sciatic Nerve Block: An Asset for Emergency Lower Limb Debridement in a High-Risk Patient.

Severe sepsis, a syndrome characterized by systemic inflammation and acute organ dysfunction in response to infection, is a major healthcare problem affecting all age groups throughout the world. Sepsis-associated encephalopathy (SAE) is a common but poorly understood neurological complication of sepsis. It is characterized by diffuse brain dysfunction secondary to infection elsewhere in the body without overt central nervous system (CNS) infection. Such cases commonly present for emergency surgical management with inadequate fasting hours, limited time for preparation, and preoperative optimization. Regional blocks become the savior in such cases where both general and central neuraxial anesthesia become perilous. Here, we present a 70-year-old male, with a case of necrotizing fascitis of the left lower limb with septic encephalopathy, with compromised cardiac or respiratory function and deranged laboratory investigations. The patient was admitted for emergency lower limb debridement, and ultrasound-guided left lower limb popliteal sciatic nerve block along with an adductor canal block was chosen as the plan of anesthesia management.

Spontaneous thrombosis with a conservative approach to posterior spinal artery pseudoaneurysm management: A case series.

In this study, we address the rarity and management challenges associated with ruptured spinal artery pseudoaneurysms, which comprise < 1% of subarachnoid hemorrhage cases. With our limited understanding of their natural history, the prevailing consensus leans towards surgical clipping, contrasting with the typically benign symptoms of sudden back pain and lower extremity weakness. Despite reported low morbidity and mortality, fatal re-ruptures underscore the need for effective management strategies. In this context, we present the largest case series to date, featuring five patients with spinal subarachnoid hemorrhage from isolated posterior spinal artery pseudoaneurysms. All cases achieved spontaneous thrombosis and resolution through conservative management, challenging the prevailing surgical emphasis. The patients, aged 58-81, exhibited varied symptoms, including back pain, paresthesia, confusion, and seizures, with hypertension as a common comorbidity. The results of these cases lead us to tender a "hybrid" management strategy, combining conservative measures with short-term follow-up angiograms, fostering a paradigm shift and warranting further investigation into individualized patient care within larger clinical cohorts.

The Gluteus Deep Investing Fascia Compartment Block: A Novel Technique for Posterior Femoral Cutaneous Nerve Block.

Purpose: The posterior femoral cutaneous nerve (PFCN) block is used in regional anesthesia for lower extremity surgery. This study introduces a new ultrasound-guided technique called the "Gluteus-Deep Investing Fascia compartment Block (GDIF block)" for blocking the PFCN. This approach involves injecting local anesthetic into the potential space between the gluteus maximus muscle and the deep investing fascia, named the 'Gluteus Deep Investing Fascia Compartment'. The study discusses the anatomical and sonographic features crucial for identifying this compartment and explores the potential benefits of this approach for achieving effective PFCN block. Additionally, it examines the clinical application of the GDIF block for PFCN block as part of the Complete Lower Extremity Fascia Tri-compartment Block technique, named "CLEFT Block." This technique combines the suprainguinal fascia iliaca block with GDIF compartment block for PFCN and a sciatic nerve block as exclusive anesthesia technique. Patients and Methods: Nine patients with weapon-related lower limb injuries underwent surgery at district hospitals supported by the International Committee of the Red Cross. Between October and December 2023, seventeen above-knee procedures were performed for the nine patients using the GDIF block as part of a CLEFT block technique. Anesthesia was performed with a CLEFT block technique using a volume ratio of 1:1 of 1% lidocaine and 0.5% levobupivacaine. Results: The GDIF block technique for PFCN blockade was performed successfully in all patients without complications, achieving complete PFCN blockade. The CLEFT block technique proved effective as the sole anesthetic technique for seventeen above-knee procedures. All surgeries were completed successfully without additional pain medication or conversion to general anesthesia. Conclusion: The GDIF block appears to be a promising technique for anesthetic management, alone or as part of the CLEFT block. Further research with a larger patient population is necessary to validate these findings.

Analysis of outcome reporting in sciatic neuropathy studies: a systematic review of the literature.

PURPOSE: As a first step towards developing a core outcome set (COS) for sciatic neuropathy, the goal of the current study was to perform a systematic review of the literature to identify outcome measures that have been previously reported in studies on sciatic neuropathy. METHODS: A systematic review of the literature from 2000-2024 was performed utilizing PubMed and Medical Subject Headings (MeSH). Identified articles were screened according to study inclusion/exclusion criteria. Outcome measures reported in each included study were recorded and categorized into motor, sensory, pain, patient-reported outcomes, electrodiagnostic outcomes, imaging outcomes, and composite outcomes. Descriptive statistics were performed. RESULTS: A total of 1586 articles were initially identified, and 31 articles met criteria for inclusion and underwent analysis. The most common outcome domain was pain. A pain outcome was reported in 17 (63%) studies. A motor outcome was reported in 10 (37%) studies; 6 (22%) reported a sensory outcome; 1 (4%) reported a composite outcome; 4 (15%) reported an electrodiagnostic outcome; 5 (19%) reported a patient-reported outcome; 3 (11%) reported an imaging outcome. Across the included studies, 21 unique outcomes were reported. CONCLUSIONS: We have identified the outcome measures that have previously been utilized in studies on sciatic neuropathy. Previously used outcome measures fell into seven domains: motor outcomes, sensory outcomes, pain outcomes, patient-reported outcomes, electrodiagnostic outcomes, imaging outcomes, and composite outcomes. Pain outcomes were most commonly used across the included studies.

Sciatic and tibial neuropathies.

The sciatic nerve is the body's largest peripheral nerve. Along with their two terminal divisions (tibial and fibular), their anatomic location makes them particularly vulnerable to trauma and iatrogenic injuries. A thorough understanding of the functional anatomy is required to adequately localize lesions in this lengthy neural pathway. Proximal disorders of the nerve can be challenging to precisely localize among a range of possibilities including lumbosacral pathology, radiculopathy, or piriformis syndrome. A correct diagnosis is based upon a thorough history and physical examination, which will then appropriately direct adjunctive investigations such as imaging and electrodiagnostic testing. Disorders of the sciatic nerve and its terminal branches are disabling for patients, and expert assessment by rehabilitation professionals is important in limiting their impact. Applying techniques established in the upper extremity, surgical reconstruction of lower extremity nerve dysfunction is rapidly improving and evolving. These new techniques, such as nerve transfers, require electrodiagnostic assessment of both the injured nerve(s) as well as healthy, potential donor nerves as part of a complete neurophysiological examination.

Piriformis syndrome.

Piriformis syndrome is a condition that is proposed to result from compression of the sciatic nerve, either in whole or in part, in the deep gluteal space by the piriformis muscle. The prevalence of piriformis syndrome depends upon the diagnostic criteria being used and the population studied but is estimated by some to be 5%-6% in all cases of low back, buttock, and leg pain and up to 17% of patients with chronic low back pain. While the sciatic nerve may pierce the piriformis muscle in about 16% of healthy individuals, this frequency is no different in those with the syndrome; thus, the relationship to this anatomic finding is unclear. The most common symptoms are buttock pain, external tenderness over the greater sciatic notch, and aggravation of the pain through sitting. Many clinical signs are reported for piriformis syndrome, but the sensitivity and specificity are unclear, in part because of the lack of a uniformly accepted case definition. In the majority of cases in the literature, it appears that the diagnosis is more ascribed to a myofascial condition rather than a focal neuropathy. Electrodiagnostic studies can be useful to exclude other causes of symptoms, but there is no well-accepted test to confirm the presence of piriformis syndrome. Ultrasound imaging may show thickening of the piriformis muscle, but further research is required to confirm that this is correlated with the clinical diagnosis. Magnetic resonance imaging and neurography may hold promise in the future, but there are not yet sufficient data to support adopting these methods as a standard diagnostic tool. The initial treatment of piriformis syndrome is typically conservative management with the general rehabilitation principles similar to other soft tissue musculoskeletal conditions. Local anesthetic, botulinum toxin, and/or corticosteroid injections have been reported by some to be beneficial for diagnostic or treatment purposes. Surgical interventions have also been used with variable success.

Anesthesia for the Patient Undergoing Foot and Ankle Surgery.

Modern anesthetic management for foot and ankle surgery includes a variety of anesthesia techniques including general anesthesia, neuraxial anesthesia, or MAC in combination with peripheral nerve blocks and/or multimodal analgesic agents. The choice of techniques should be tailored to the nature of the procedure, patient comorbidities, anesthesiologist skill level, intensity of anticipated postoperative pain, and surgeon preference.

[Comparison of the effects of sciatic nerve block combined with continuted femoral nerve block or continuted adductor canal block on pain and motor function after total knee arthroplasty].

Objective: To compare the effect of sciatic nerve block (SNB) combined with continuted femoral nerve block (FNB) or continuted adductor canal block (ACB) on pain and motor function after total knee arthroplasty (TKA). Methods: A total of 60 patients with TKA-treated osteoarthritis of the knee who met the selection criteria were enrolled between November 2020 and February 2021 and randomised allocated into the study group (SNB combined with continuted ACB) and the control group (SNB combined with continuted FNB), with 30 cases in each group. There was no significant difference in gender, age, body mass, height, body mass index, preoperative Hospital for Special Surgery (HSS) score, femoral tibial angle, and medial proximal tibial angle between the two groups ( P>0.05). The operation time, the initial time to the ground, the initial walking distance, and the postoperative hospital stay were recorded. At 2, 4, 6, 12, 24, and 48 hours after operation, the numerical rating scale (NRS) score was used to evaluate the rest pain around the knee joint, the quadriceps femoris muscle strength was evaluated by the freehand muscle strength method, and the knee flexion and extension angles were measured. Results: There was no significant difference in the operation time and initial walking distance between the two groups ( P>0.05); the initial time to the ground and postoperative hospital stay of the study group were significantly shorter than those of the control group ( P<0.05). Except for the 48-hour postoperative NRS score of the study group, which was significantly lower than that of the control group ( P<0.05), there was no significant difference in the NRS scores between the two groups at the remaining time points ( P>0.05). The quadriceps femoris muscle strength from 4 to 24 hours postoperatively and the knee extension angle from 2 to 6 hours postoperatively of the study group were significantly better than those of the control group ( P<0.05); the differences in the quadriceps femoris muscle strength and knee extension and flexion angles between the two groups at the remaining time points were not significant ( P>0.05). Conclusion: SNB combined with either continuted ACB or continuted FNB can effectively relieve pain in patients after TKA, and compared with combined continuted FNB, combined continuted ACB has less effect on quadriceps femoris muscle strength, and patients have better recovery of knee flexion and extension mobility.

Postoperatively Noninvasive Optogenetic Stimulation via Upconversion Nanoparticles Enhancing Sciatic Nerve Repair.

The efficacy of electrical stimulation facilitating peripheral nerve regeneration is evidenced extensively, while the associated secondary damage resulting from repeated electrode invasion and indiscriminate stimulation is inevitable. Here, we present an optogenetics strategy that utilizes upconversion nanoparticles (UCNPs) to convert deeply penetrating near-infrared excitation into blue emission, which activates an adeno-associated virus-encoding ChR2 photoresponsive ion channel on cell membranes. The induced Ca2+ flux, similar to the ion flux in the electrical stimulation approach, efficiently regulates viability and proliferation, secretion of nerve growth factor, and neural function of RSC96 cells. Furthermore, deep near-infrared excitation is harnessed to stimulate autologous Schwann cells in situ via a UCNP-composited scaffold, which enhances nerve sprouting and myelination, consequently promoting functional recovery, electrophysiological restoration, and reinnervation of damaged nerves. This developed postoperatively noninvasive optogenetics strategy presents a novel, minimally traumatic, and enduring therapeutic stimulus to effectively promote peripheral nerve repair.

Foreign substance injection for esthetic purposes associated with delayed unilateral sciatic nerve impairment: A surgical case report.

Attempts at body contour modifications have led to the use of different alloplastic materials that can irreversibly damage health and risk patients' lives. These modeling substances can induce a general autoimmune inflammatory response, producing a very heterogeneous clinical spectrum ranging from mild and severe systemic to local symptoms that sometimes affect peripheral nerves. We report a unique case of a tumor-like sciatic nerve impairment produced months after the injection of a modeling substance into the buttocks for esthetic purposes. The patient was treated with a surgical decompression of the sciatic nerve that encompassed the removal of the injected mass. This approach ultimately yielded a complete neurological recovery of the affected nerve. We emphasize the diagnostic approach and surgical management employed in this unique case and review the current literature on this infrequent complication.

Case report: Solitary mass of the sciatic nerve confirmed as a primary extranodal manifestation of diffuse large B-cell lymphoma in a geriatric patient.

Background: Neoplastic lesions affecting peripheral nerves are rare in the general population and, most often, are benign peripheral nerve sheath tumors. However, a minority of lesions represent high-grade malignancies associated with a poor prognosis, such as malignant peripheral nerve sheath tumors (MPNSTs). Very rarely, these tumors represent peripheral non-nerve sheath tumors (PNNSTs), such as hematological neoplasms that impair nerve function. These can be hard to distinguish from MPNSTs and other lesions arising from the nerve itself. In the present case report, we describe a rare case of direct infiltration of nerves by tumor cells of a hematological neoplasm. Methods: We report the case of a 90-year-old woman with acute onset of right-sided foot palsy, sensory loss, and pain, caused by an extensive solitary mass of the sciatic nerve in the thigh. We present and discuss the clinical presentation, multimodal diagnostic procedures, and treatment. Results: MRI of the right thigh and the caudal pelvis revealed a contrast-enhancing lesion infiltrating the sciatic nerve. Additionally performed staging imaging was non-revealing. After multidisciplinary discussion in the neuro-oncology tumor board, a MPNST was suspected and the patient underwent radical tumor resection. However, final histopathology revealed a diffuse large B-cell lymphoma (DLBCL). The patient received adjuvant palliative local radiotherapy which led to acceptable symptom control. Conclusion: Rare PNNSTs, including extranodal manifestations of DLBCL can have similar clinical and radiological diagnostical features as PNSTs. Comprehensive diagnostic workup of contrast-enhancing lesions affecting peripheral nerves including MRI and metabolic imaging are recommended. Discussion in interdisciplinary tumor boards facilitates finding individual treatment approaches.

Dexamethasone versus Dexmedetomidine as Adjuvants in Ultrasound Popliteal Sciatic Nerve Block for Hallux Valgus Surgery: A Mono-Centric Retrospective Comparative Study.

Background and Aim: Ultrasound popliteal sciatic nerve block (UPSNB) is commonly performed in foot and ankle surgery. This study aims to assess the use of dexmedetomidine and dexamethasone as adjuvants in UPSNB for hallux valgus (HV) surgery, comparing their efficacy in producing motor and sensory block and controlling postoperative pain. The adverse event rate was also evaluated. Methods: This mono-centric retrospective study included 62 adult patients undergoing HV surgery: 30 patients received lidocaine 2% 200 mg, ropivacaine 0.5% 50 mg and dexamethasone 4 mg (Group 1), whereas 32 patients received lidocaine 2% 200 mg, ropivacaine 0.5% 50 mg, and dexmedetomidine 1 mcg/Kg (Group 2). At first, the visual analogue scale (VAS) was evaluated after 48 hours. The other outcomes were time to motor block regression, evaluation of the first analgesic drug intake, analgesic effect, adverse effects (hemodynamic disorders, postoperative nausea and vomiting (PONV)) and patient satisfaction. The continuous data were analyzed with student's t-test and the continuous one with χ2. Statistical significance was set at a p-value lower than 0.05. Results: No significant difference was found in VAS after 48 hours (4.5 ± 1.6 vs 4.7 ± 1.7, p = 0.621) to motor block regression (18.9 ± 6.0 vs 18.7 ± 6, p = 0.922). The number of patients that took their first analgesic drug in the first 48 h (p = 0.947 at 6 hours; p = 0.421 at 12 hours; p = 0.122 at 24 hours and p = 0.333 at 48 hours) were not significant. A low and similar incidence of intraoperative hemodynamic disorders was recorded in both groups (hypotension p = 0.593; bradycardia p = 0.881). Neither PONV nor other complication was found. Patients in Group 1 reported a lower degree of interference with sleep (p = 0.001), less interference with daily activities (P = 0.002) and with the affective sphere (P = 0.015) along with a more satisfactory postoperative pain management (p < 0.001) as compared to Group 2. Conclusion: No significant differences were observed in the duration of motor and sensory blockade between patients in both groups. Additionally, both groups showed good pain control with a low rate of adverse effects, even if there was no clinical difference between the groups. However, patients who received dexamethasone reported experiencing less interference with their sleep, daily activities and overall emotional well-being, and overall pain control.

A Bilateral Symmetrical Variant Formation of the Sural Nerve.

Typically, the sural nerve is formatted by the connection of the lateral sural cutaneous nerve (branch of the common fibular nerve) and the medial sural cutaneous nerve (branch of the tibial nerve). The current cadaveric report aims to describe a quite unusual symmetrical variant of the sural nerve. Classical dissection was performed on an 84-year-old donated male cadaver. On both sides, the sural nerve was formatted directly by the sciatic nerve. After its emanation, it continued its typical course between the gastrocnemius muscle heads. Sural nerve formation has been extensively studied due to its great clinical significance. The identified variant corresponds to one of the rarest types of sural nerve formation. Knowledge of sural nerve variants may play a crucial role in lower limb surgery and nerve harvest for reconstruction.

Concomitant treatment of ureteral calculi and ipsilateral pelvic sciatic nerve schwannoma with transperitoneal laparoscopic approach: A case report.

BACKGROUND: Schwannomas are rare peripheral neural myelin sheath tumors that originate from Schwann cells. Of the different types of schwannomas, pelvic sciatic nerve schwannoma is extremely rare. Definite preoperative diagnosis of pelvic schwannomas is difficult, and surgical resection is the gold standard for its definite diagnosis and treatment. CASE SUMMARY: We present a case of pelvic schwannoma arising from the sciatic nerve that was detected in a 40-year-old man who underwent computed tomography for intermittent right lower back pain caused exclusively by a right ureteral calculus. Subsequently, successful transperitoneal laparoscopic surgery was performed for the intact removal of the stone and en bloc resection of the schwannoma. The total operative time was 125 min, and the estimated blood loss was inconspicuous. The surgical procedure was uneventful. The patient was discharged on postoperative day 5 with the simultaneous removal of the urinary catheter. However, the patient presented with motor and sensory disorders of the right lower limb, caused by partial damage to the right sciatic nerve. No tumor recurrence was observed at the postoperative appointment. CONCLUSION: Histopathological examination of the specimen confirmed the diagnosis of a schwannoma. Thus, laparoscopic surgery is safe and feasible for concomitant extirpation of pelvic schwannomas and other pelvic and abdominal diseases that require surgical treatment.