Search Results (15)

Background/Objectives: The level of the sciatic nerve bifurcation is clinically relevant for diagnostic ultrasonography, ultrasound-guided popliteal sciatic nerve block, posterior-thigh interventions, and surgical approaches to the hip, thigh, and popliteal region. Although the sciatic nerve is classically described as dividing near the popliteal fossa, its terminal branching level may vary considerably. This study aimed to evaluate the level of sciatic nerve bifurcation and its morphometric relationship to clinically relevant anatomical landmarks, with particular emphasis on the posterior intercondylar reference line. Methods: This study was conducted on 56 formalin-fixed adult human lower-extremity specimens. The bifurcation level was categorized as femoral-level, gluteal-level, or separate emergence of the tibial and common fibular components. The sciatic nerve–piriformis relationship was assessed according to the Beaton and Anson classification. Morphometric measurements were obtained from the bifurcation point to the greater trochanter, ischial tuberosity, and posterior intercondylar reference line. Results: Femoral-level bifurcation was observed in 51 of 56 specimens (91.1%), gluteal-level bifurcation in 1 specimen (1.8%), and separate emergence in 4 specimens (7.1%). Type A was the predominant Beaton and Anson pattern, observed in 50 specimens (89.3%). Type B and Type D were each observed in 2 specimens (3.6%), and 2 specimens (3.6%) demonstrated an atypical superior gemellus-related course. All measurable bifurcation points were located proximal to the posterior intercondylar reference line. Among femoral-level bifurcations, the mean distance from this line to the bifurcation point was 8.67 ± 4.89 cm. No statistically significant sex- or side-based differences were observed in the available morphometric parameters. Conclusions: Sciatic nerve bifurcation most commonly occurred at the femoral level, but clinically relevant variations were observed. The posterior intercondylar reference line may provide a useful distal femoral orientation landmark for posterior knee and distal thigh assessment. However, it should complement, rather than replace, direct ultrasonographic visualization of the sciatic nerve and its terminal branches. Full article

Background/Objectives: Pressure pain thresholds (PPTs) are widely used to quantify hyperalgesia in tension-type headache (TTH). However, previous diagnostic accuracy research has mainly focused on muscular or segmental sites, while the discriminative performance of PPTs measured over peripheral nerves remains largely unexplored. This study primarily aimed to compare PPTs measured across nerve-related and muscular anatomical sites between women with frequent episodic TTH and headache-free controls. As a secondary exploratory objective, site-specific ROC analyses were performed to examine within-sample discrimination and derive sample-specific exploratory cut-offs. Methods: A cross-sectional exploratory study with a case–control sampling design evaluated 31 women with frequent episodic TTH (mean age: 19.6 ± 4.3 years) and 32 headache-free women (mean age: 22.1 ± 4.9 years). The groups differed significantly in age (p = 0.039). PPTs were recorded over peripheral nerves (greater occipital, median, ulnar, radial, tibial, common fibular), muscles (temporalis, tibialis anterior), 2nd–3rd interdigital hand space and the C5/C6 zygapophyseal joints. Results: Women with TTH showed lower PPTs than controls across all evaluated locations. However, after adjustment for age and Holm correction across the 20 anatomical sites, only the right greater occipital nerve remained statistically significant (p = 0.043). The right greater occipital nerve also yielded the highest area under the curve (AUC = 0.706; 95% CI 0.576–0.836) and was the only location whose AUC remained significantly different from 0.50 after correction for multiple testing (p = 0.040). Its sample-derived exploratory cut-off of 1.75 kg/cm² showed low sensitivity (0.419; 95% CI 0.245–0.609) but high specificity (0.969; 95% CI 0.838–0.999). Although the corresponding LR+ was 13.419, its confidence interval was extremely wide (95% CI 1.866–96.525), indicating substantial imprecision. The LR− was 0.599 (95% CI 0.442–0.814). Overall, the operating characteristics varied considerably across locations and should be interpreted as exploratory. Conclusions: Women with frequent episodic TTH showed generally lower PPTs across nerve and muscle locations. However, after adjustment for age and multiple testing, the between-group difference was statistically supported only at the right greater occipital nerve. Although this location showed the highest AUC and high specificity at the sample-derived cut-off, its low sensitivity and the considerable imprecision of the LR+ estimate limit its interpretation. These findings reflect discrimination between selected participants with established TTH and headache-free controls, and should not be interpreted as evidence of clinical differential-diagnostic accuracy. Full article

Background: Focal entrapment of the Common Peroneal (Fibular) nerve (CPN) is the most frequent lower-extremity nerve entrapment yet it can be difficult to diagnose clinically. The Phoenix Sign—an increase in extensor hallucis longus (EHL) motor strength following lidocaine injection—may assist diagnosis. Additional observed effects include improved arterial perfusion and Doppler waveforms. Methods: In this double-blinded, randomized small pilot study, only four patients (N = 4) with diabetic peripheral neuropathy underwent bilateral peripheral nerve blocks with lidocaine or papaverine. The first leg to be tested was randomized; the contralateral leg received a different agent that was randomized initially. Pre- and post-block assessments included motor strength, Doppler velocity of dorsalis pedis and posterior tibial arteries, and near-infrared spectroscopy for microvascular perfusion. Results: All patients demonstrated increased EHL motor strength after injection with either agent. Doppler waveforms of the dorsalis pedis artery improved: lidocaine produced a 151.7% increase in blood flow velocity (p = 0.03), whereas papaverine produced a 16.8% increase (p = 0.19). Posterior tibial artery flow increased by 37.4% with lidocaine (p = 0.06) and 13.9% with papaverine (p = 0.33), but neither was statistically significant. No changes in oxygen saturation, oxyhemoglobin, deoxyhemoglobin, or total hemoglobin were observed using near-infrared spectroscopy. The consistency of motor responses across subjects supports the validity of the Phoenix Sign as a diagnostic tool. Conclusions: Peripheral nerve blocks with lidocaine or papaverine improved motor strength and macrovascular function in patients with diabetic peripheral neuropathy, though microvascular changes were not detected. These preliminary findings are consistent with the Phoenix Sign phenomenon and support further study as a potential clinical indicator. While these preliminary findings indicate support as a diagnostic tool, they are preliminary and hypothesis-generating for evaluating the Phoenix Sign as a potential clinical indicator of CPN entrapment and highlight the need for larger studies to evaluate vascular responses. Trial Registration: NCT06919289 (retrospectively registered 8 April 2025). Full article

Campanacci grade III giant cell tumors of the distal radius frequently require en bloc resection to achieve adequate oncologic control. Reconstruction of the resulting defect remains challenging, particularly with respect to preservation of distal radioulnar joint stability and forearm rotation. Although proximal fibular autograft reconstruction is well established, ligamentous stabilization of the distal radioulnar joint is rarely incorporated in oncologic settings. This technical note describes an integrated reconstructive strategy combining proximal fibular autograft with distal oblique bundle reconstruction, illustrated by a representative clinical case. The technique involves segmental en bloc resection of the distal radius followed by reconstruction using an ipsilateral, nonvascularized proximal fibular autograft including the fibular head. Distal radioulnar joint stability is addressed through reconstruction of the distal oblique bundle using an autologous palmaris longus tendon graft. Surgical indications, operative steps, donor site stabilization, and perioperative management are detailed. Functional evolution was assessed using the Musculoskeletal Tumor Society scoring system and range-of-motion measurements. Histopathological examination confirmed negative oncologic margins. Early postoperative events included donor-site common peroneal nerve dysfunction and radiocarpal instability requiring temporary Kirschner wire stabilization. At nine months, the Musculoskeletal Tumor Society score reached 80%, with forearm rotation preserved at 68.8% pronation and 81.3% supination of normal values. Combined osseous and ligamentous reconstruction following distal radius resection is technically feasible and may allow preservation of distal forearm mechanics while maintaining oncologic principles. Broader validation will require application in larger clinical series and longer follow-up. Full article

Background and Objectives: Osteoarthritis (OA) is a common cause of chronic pain. In refractory cases, cooled radiofrequency (CRF) of the genicular nerves is indicated. However, recent studies suggest that traditional targets may be insufficient, proposing the inclusion of the recurrent fibular nerve and the infrapatellar branch of the saphenous nerve. This study reports a prospective four-case series evaluating short-term outcomes of CRF at five revised targets in elderly Brazilian patients. Case Report: The study (CAAE No.: 55647722.5.0000.5142) included four patients (three women, one man; mean age 73.8 years) with moderate to severe refractory knee pain underwent diagnostic nerve block followed by ultrasound-guided CRF. After 30 days, three patients reported pain reduction, including two who experienced substantial improvement. One patient maintained severe pain. Improvements in physical performance, knee flexion, and extension were observed in patients who responded clinically, while individuals with coexisting myofascial pain showed limited functional gains. One patient experienced mild transient pruritus. In this prospective case series, CRF applied to five revised targets appeared feasible and well tolerated, with short-term improvement in pain and function in some patients. These preliminary descriptive findings support further investigation in larger controlled studies. Full article

Background/Objectives: The co-existence of multiple compression sites on the same nerve can pose a clinical and diagnostic challenge, warranting a different treatment strategy. This so-called double crush syndrome (DCS) has mainly been investigated in the upper limb. Only a few studies have investigated DCS for the lower limb. In this article, a single-center illustrative clinical case series is presented, and current literature on L5 nerve root (NR) and concomitant common peroneal nerve (CPN) is reviewed. Methods: All patients presenting between 2019 and 2022 with L5 nerve root (NR) compression and, along their clinical courses, concomitant compression of the common peroneal nerve (CPN) at the fibular head were included. Information on clinical features, diagnostics and surgeries was obtained. The outcome was assessed at the last outpatient follow-up appointment. In addition, an extensive literature review has been conducted. Results: Fourteen patients were included with a mean follow-up of 6.8 months. The majority had pain (71%) or motor deficits (71%). Seven patients were referred for clinical and radiological L5 NR compression but were also found to have CPN compression; the other seven patients had persisting or recurrent symptoms after surgically or conservatively treated L5 NR compression, suggestive of additional peroneal neuropathy. All patients had CPN decompression at the fibular head, with successful results obtained in 93% of the patients. Pain of the lower leg improved in all patients, and dorsiflexion function improved in 78%. Conclusions: Concomitant L5 NR and CPN appear to occur more frequently than expected. Peroneal neuropathy can present simultaneously with L5 nerve radiculopathy or after surgically or conservatively treated L5 NR compression. Overlapping symptoms and variation in clinical presentations make it difficult to diagnose and, therefore, underrecognized. More awareness among treating physicians of this specific double crush syndrome is important to prevent any delay in treatment, in this case, a less invasive common peroneal nerve release at the fibular head, and to avoid unnecessary (additional) spinal surgery. Full article

Regional anesthesia techniques targeting articular nerve branches offer promising avenues for managing articular pain. This study developed and compared the success rates of an ultrasound-guided versus a blind pericapsular knee desensitization (PKD) technique in canine cadavers. In Phase I, gross dissection and ultrasound evaluations were performed in eight limbs to characterize the anatomy of the medial (MAN), lateral (LAN), and posterior (PAN) articular branches of the saphenous, common fibular, and tibial nerves, respectively, and to identify suitable anatomical and ultrasonographic landmarks. In Phase II, ultrasound-guided and blind PKD injections of a dye solution were randomly performed in 10 cadavers (20 limbs), followed by dissection and histological assessment of staining accuracy. The ultrasound-guided technique achieved a significantly higher overall success rate (96.7%) than the blind technique (73.3%; p = 0.02). The MAN was successfully stained in 100% of ultrasound-guided and 50% of blind injections (p = 0.03), while the LAN and PAN were stained with high but comparable success. Parent nerve involvement was minimal for MAN and PAN but frequent for the common fibular nerve following LAN injections. Histological confirmation supported the anatomical findings, although PAN identification remained inconsistent. These results support the feasibility and increased precision of ultrasound-guided PKD, providing a foundation for further clinical evaluation. Full article

Background: Previous studies have indicated that transcutaneous electrical nerve stimulation (TENS) is highly effective in improving the treatment of neuropathy and achieving maximum recovery in the shortest time. However, its effectiveness in the early stages of the disease has not been studied, and no comparative analysis has been conducted between different modalities of TENS. Materials and Methods: This study included 82 patients with acute and subacute fibular tunnel (FT) syndrome lasting no more than 15 days. Patients were randomized into the following four groups depending on the modality of TENS used: sham TENS (20 patients), HF TENS (20 patients), LF TENS (21 patients), and a combined HF/LF TENS group (21 patients). Before treatment, immediately after treatment, and 3 months after the end of treatment patients were examined to determine the severity of hypoesthesia, motor deficit, and gait disturbance. Results: The reduction in hypoesthesia averaged after HF TENS, LF TENS, and sham TENS was 50.7% (p ≤ 0.01), 37.8 (p ≤ 0.01), and 11.4% (p > 0.05), respectively. The regression of motor deficit and gate disorders reached 61% after LF TENS (p ≤ 0.01), 6% after HF TENS (p > 0.05), and 6% (p > 0.05) after sham TENS. The combination of HF and LF TENS resulted in a 54.8% (p ≤ 0.01) reduction in hypoesthesia and 61.3% (p ≤ 0.01) regression of motor deficit, with a superior 30% (p ≤ 0.05) improvement in quality of life compared to separate use of HF and LF TENS. Conclusions: Early use of TENS in the treatment of FT syndrome turned out to be highly effective compared to sham TENS in reducing hypoesthesia, motor deficit, and gait disturbance. The analgesic effect and sensory recovery were higher after HF TENS. Motor and gait disturbances were reduced only after LF TENS, with evidence of prolonged regenerative and protective effect for at least 3 months after the end of treatment. The combination of HF TENS and LF TENS increases the therapeutic range of TENS with the achievement of the maximum positive effect of HF TENS and LF TENS after treatment and during the long-term period, which leads to a more pronounced improvement in the quality of life of patients with this pathology. Full article

Common peroneal nerve neuropathy at the fibular head secondary to weight loss is known as slimmer’s paralysis. Although this pathology has long been documented in medical literature, it has gained more clinical significance in recent years due to the global rise in obesity and the increasing pursuit of rapid weight loss methods. While case reports exist in the current literature, there are limited data regarding its optimal management. This study summarizes all reported cases of common peroneal nerve paralysis after weight loss and reports one additional case, exploring disease mechanisms as well as diagnostic and therapeutic strategies. A literature review was conducted on the platforms PubMed, Google Scholar, and EMBASE. A total of 380 patients were included. Laterality of neuropathy was specified in 297 (78.16%) patients: 285 (95.96%) with unilateral neuropathy and 12 (4.04%) with bilateral neuropathy. A total of 19 (5.00%) patients had sudden onset, and in 145 (38.16%) of cases, the Tinel’s sign was positive. Additionally, 373 (98.16%) patients underwent nerve conduction studies, demonstrating the fibular head as the site of injury. MRI or ultrasound imaging of the knee is indicated to exclude compressive etiology. A total of 302 (79.47%) cases were treated surgically and 42 (11.58%) conservatively, predominantly with favorable outcomes, regardless of the therapeutic approach chosen. Although the predominance of surgically treated cases in the literature limits definitive treatment recommendations, conservative management appears appropriate when an extended recovery time is acceptable, while surgical decompression is indicated in cases showing no improvement after 3 months. Full article

Background and Objectives: Proximal tibiofibular joint detachment (PTFJD) is a fibular untethering procedure during lateral closing-wedge high tibial osteotomy (LCWHTO) for varus knee osteoarthritis. However, the PTFJD procedure is technically demanding, and confirmation of clear joint separation is not straightforward. The aim of this study was to compare the degree of completion and safety of PTFJD versus tibial-sided osteotomy (TSO); this latter procedure is our novel technique for fibular untethering during LCWHTO. Materials and Methods: Sixteen fresh frozen cadaver knees from eight cadavers were included in the study. Among the eight pairs of knees, one knee was randomly assigned to undergo PTFJD and the other knee to undergo TSO, which separates the fibula by osteotomizing the lateral cortex of the proximal tibia at the medial side of the proximal tibiofibular joint for fibular untethering during LCWHTO. After each procedure with LCWHTO, the posterior compartment of each knee was dissected to compare the degree of procedural completion and the distance from the posterior detachment or osteotomy site to posterior neurovascular structures between PTFJD and TSO groups. The pass-through test crossing the separation site from anterior to posterior using an osteotome was also performed to evaluate the protective effect of the muscular structures of the posterior compartment. Results: In the PTFJD group, four of eight cases (50%) showed fibular head fractures rather than division of the proximal tibiofibular joint. In contrast, in all TSO cases, the lateral cortex of the proximal tibia was clearly osteotomized from the medial side of the posterior proximal tibiofibular joint. Distances from the posterior detachment or osteotomy site to the common peroneal nerve, popliteal artery, and anterior tibial artery in the PTFJD and TSO groups were 20.8 ± 3.3 mm and 22.9 ± 3.6 mm (p = 0.382), 11.0 ± 2.4 mm and 9.8 ± 2.8 mm (p = 0.382), and 14.8 ± 1.9 mm and 14.9 ± 2.5 mm (p = 0.721), respectively. In the pass-through test, an osteotome was able to pass anteriorly to posteriorly in all eight PTFJD group cases. However, the osteotome was blocked posteriorly by the popliteus muscle in the TSO group cases, indicating protection of posterior neurovascular structures during the TSO procedure. Conclusions: TSO, a novel fibular untethering procedure for LCWHTO, resulted in clear separation of the fibula from the lateral tibial cortex, and protection of posterior neurovascular structures by the popliteus muscle during the procedure. We anticipate that our novel surgical technique will provide more clear-cut and safer fibular untethering for LCWHTO. Full article

Background/Objectives: Acute lateral ankle sprain (ALAS) affects balance, often assessed by changes in traditional center of pressure (COP) parameters. Spatiotemporal measures of COP and time-to-boundary (TTB) analysis may offer improved sensitivity in detecting postural deviations associated with ALAS. However, the neurophysiological mechanism underlying these changes remains unknown. This study aimed to explore the effects of ALAS on spinal reflex excitability in the fibularis longus (FL) during single-leg balance and TTB parameters following ALAS. Methods: Fourteen participants with and without ALAS were recruited within 14 days from the onset of the injury. We assessed FL spinal reflex excitability and postural control during a single-leg stance. The primary outcomes included the H/M ratio, H-latency, and TTB parameters. For H-reflex testing, the peripheral electrical stimulation was delivered at the sciatic nerve before bifurcating into the tibial and common fibular nerve while participants maintained a single-leg balance position with the involved side of the limb. The TTB parameters of the medial–lateral (ML) and anterior–posterior (AP) directions of the mean, SD, and minimum were assessed, which indicate postural correction and strategies. Results: Patients with ALAS had a significantly lower AP-TTB minimum compared with healthy uninjured controls, with a moderate effect size (p = 0.039; d = −0.83). However, there was no significant difference in the H/M ratio (ALAS: 0.29 ± 0.16 vs. CON: 0.24 ± 0.10; p = 0.258) and H-reflex latency (ALAS: 34.6 ± 1.92 vs. CON: 33.8 ± 1.75 ms; p = 0.277); Conclusions: These results indicate that reflex control at the spinal level may have a minimal role in response to balance deficits following ALAS. Full article

The sural nerve provides sensory innervation to the skin on the distal posterolateral third of the lower extremity. The morphological variants are characterized by high variability. However, it most commonly arises from a union of the medial sural cutaneous nerve and the peroneal communicating branch of the common fibular nerve. This article overviews the anatomical and clinical significance of the sural nerve. Despite the remarkable development of genetic diagnostics, sural nerve biopsy is still a very important tool to diagnose peripheral neuropathies such as diabetic, vascular and inflammatory neuropathies. Furthermore, the sural nerve is also commonly transplanted due to its characteristics. Such a procedure is applicable in cases of segmental nerve loss, but it is also used to restore potency in patients after radical prostatectomy. The knowledge of anatomical variants of the sural nerve is also crucial as it allows to minimize its damage during surgical procedures. Furthermore, during an ankle surgery, a nerve block can be used to complement anesthesia. The major aim of this work is to review contributions of the sural nerve to physiological and pathophysiological processes. Full article

Background: We evaluated patients who were followed after acutely developing single-sided footdrop and improving with conservative management or spontaneously. Methods: In 2019 and 2020, ten patients were retrospectively evaluated for unilateral weakness of the lower extremity in the form of absent dorsiflexion at the ankle joint and were given a diagnosis of footdrop without etiologic cause. Patients were followed for 18 months. Patients were evaluated for acute footdrop of the affected extremity with electromyography, lumbar spine magnetic resonance imaging (MRI), knee MRI, peripheral MRI neurography, and noncontrast brain MRI. Each patient was evaluated for a history of COVID-19 infection during the past year. Patients with any identified cause were excluded. Results: Initial evaluation of muscle strength revealed 0/5 by the Medical Research Council muscle testing scale. In two patients, muscle strength was 3/5 at month 6 and in eight patients it was 4/5. Muscle strength of all of the patients improved to 5/5 at 1 year. Six patients were dispensed an ankle-foot orthosis, and nine patients performed physical therapy. Electromyography identified significant neuropathy at the level of the common peroneal at the fibular head in all of the patients. Compared with peroneal nerve stimulation below and above the fibular head in the lateral popliteal fossa, a 50% reduction in sensory amplitude and motor conduction slowing greater than 10 m/sec were present. Knee MRI revealed no masses, edema, or anatomical variations at the level of the fibular head. Conclusions: Spontaneous resolution of unilateral acute footdrop without an etiologic cause can occur within 1 year. (J Am Podiatr Med Assoc 114(5), 2024; doi:10.7547/22-080) Full article

Introduction: Pain after cervicofacial cancer surgery with free flap reconstruction is both underestimated and undertreated. There is a rational for regional anesthesia at the flap harvest site, but few studies describe it. We assessed the influence of common peroneal nerve infiltration on pain and opioid consumption in patients having oropharyngeal cancer surgery with fibular free flap mandibular reconstruction. Methods: After institutional review board (IRB) approval and written informed consent, fifty-six patients were randomly allocated to perineural catheter with ropivacaine infiltration (ROPI) or systemic analgesia (CONTROL). In the ROPI group, an epidural catheter was placed by the surgeon before closure, and ropivacaine 0.2% 15 mL, followed by 4 mL/h during 48 h, was administered. The primary outcomes were pain scores and morphine consumption during the 48 h postoperative period. We also measured ropivacaine concentration at the end of infusion. Finally, we retrospectively assessed long-term pain up to 10 years using electronic medical charts. Results: Perineural infiltration of ropivacaine significantly reduced pain scores at the harvest site only at day 1, and did not influence overall postoperative opioid consumption. Ropivacaine assay showed a potentially toxic concentration in 50% of patients. Chronic pain was detected at the harvest site in only one patient (ROPI group), and was located in the cervical area in the case of disease progression. Discussion: Although the catheter was visually positioned by the surgeon, continuous ropivacaine infiltration of the common peroneal nerve did not significantly reduce postoperative pain, but induced a blood concentration close to the toxic threshold at day 2. Further studies considering other infiltration locations or other dosing schemes should be tested in this context, both to improve efficacy and reduce potential toxicity. Full article

Distal to its origination from the sciatic nerve, the common fibular (peroneal) nerve divides into the superficial and deep fibular (peroneal) nerves. Whereas the deep fibular nerve continues its course into the anterior compartment, the superficial fibular nerve (SFN) usually arises near the fibular neck and projects distally within the lateral crural compartment before entering the superficial fascia proximal to the ankle. In this report, we describe a unilateral case where the SFN arises within the anterior crural compartment and remains there for the remainder of its course deep to the deep fascia of the leg. Surgeons should be aware of anomalies such as this, for example, when performing fasciotomies to avoid inadvertently damaging an anomalously placed SFN. Full article