Search Results (220)

Spinal cord stimulation (SCS) has expanded beyond pain treatment, becoming a neuromodulatory method capable of recruiting spinal and supraspinal circuits involved in motor recovery. This review summarises mechanistic knowledge, supports engineering developments, and describes the changing clinical translation of SCS in rehabilitation. Mounting scientific data shows that SCS’s effects go beyond dorsal column modulation and may involve segmental networks that promote activity-dependent plasticity and sensorimotor pathway restoration, probably due to a combination of Hebbian and non-Hebbian mechanisms (synaptic potentiation, interneuronal reorganisation, and altered afferent–efferent coupling). More recent advances, such as bursts and the high-frequency paradigm, closed-loop control, and data-driven parameter optimisation methods, improve the precision, stability, and calibration of stimulation for each individual. By combining SCS with non-invasive forms of neuromodulation (TMS, tDCS, and peripheral nerve stimulation), one can potentially further intensify corticospinal plasticity and maintain improvements in functions. Spinal cord stimulation remains an established treatment for chronic neuropathic pain, including failed back surgery syndrome and complex regional pain syndrome. In recent years, however, increasing attention has been directed toward its potential role in motor recovery after spinal cord injury and stroke. Progress in this area is limited by patient heterogeneity, variability in outcome measures, the complexity of multimodal rehabilitation protocols, and regulatory and logistical constraints—particularly when adaptive or closed-loop systems are used. Current evidence suggests that motor-restorative applications of SCS should be interpreted cautiously and integrated within carefully designed rehabilitation programmes, with attention to patient selection and realistic expectations regarding the durability of the benefit. Full article

Background: Predicting functional recovery after selective nerve transfer remains challenging. Intraoperative nerve action potential (NAP) recording is widely used to confirm axonal continuity in peripheral nerve surgery; however, its quantitative prognostic value in selective nerve transfer has not been clearly established. This study evaluated whether intraoperative donor fascicle NAP amplitude predicts functional recovery following selective ulnar-to-musculocutaneous nerve transfer (Oberlin procedure) for restoration of elbow flexion. Methods: This retrospective exploratory observational study included 20 patients who underwent selective ulnar-to-musculocutaneous nerve transfer (Oberlin procedure) with standardized intraoperative neurophysiological mapping and quantitative donor fascicle NAP recording. Functional outcome specific to elbow flexion was assessed at last follow-up using the Medical Research Council (MRC) grading system. Time to first electromyographic evidence of biceps reinnervation was recorded. Associations between intraoperative NAP amplitude and functional, temporal, and clinical variables were analyzed using Spearman’s rank correlation coefficient and non-parametric tests. Results: Donor NAP amplitude demonstrated substantial interindividual variability (range 60–400 µV; median 137.5 µV, IQR 87.5–200 µV). No significant associations were observed between NAP amplitude and final MRC grade (ρ = −0.103; p = 0.666), time to electromyographic reinnervation (days: ρ = −0.123; p = 0.617), patient age, or time from injury to surgery. A moderate negative correlation between NAP amplitude and lesion severity was observed but did not reach statistical significance in this small cohort (ρ = −0.419; p = 0.0659). In contrast, shorter time to electromyographic reinnervation was significantly associated with improved final functional outcome (ρ = −0.559; p = 0.013). No patient reported postoperative hand weakness. Conclusions: In this exploratory cohort, intraoperative donor NAP amplitude was not associated with time to electromyographic reinnervation or final elbow flexion strength following selective ulnar-to-musculocutaneous nerve transfer. Although intraoperative NAP mapping remains essential to confirm axonal continuity and conduction viability of the donor fascicle, NAP amplitude did not demonstrate prognostic value in this cohort and should be interpreted cautiously as an isolated predictor of functional recovery, particularly given the limited sample size and exploratory design. These findings suggest that recovery after selective nerve transfer may be influenced by broader biological determinants, including regenerative timing, rather than by isolated intraoperative amplitude metrics. Full article

Background/Objectives: Wide Awake Local Anesthesia No Tourniquet (WALANT) and ultrasound-guided peripheral nerve blocks (PNBs) are increasingly used alternatives to general anesthesia for hand and forearm surgery. While WALANT is commonly perceived as a time-efficient and resource-sparing technique, comparative data regarding patient satisfaction, perioperative pain, and time-related outcomes remain inconsistent. This study aimed to compare WALANT and ultrasound-guided supraclavicular peripheral nerve block techniques with respect to patient satisfaction, perioperative pain, time-related parameters, and surgeon-related outcomes in elective hand and forearm extremity surgery. Methods: This prospective comparative observational study included 80 adult patients undergoing elective hand or forearm surgery. Patients received either WALANT or ultrasound-guided supraclavicular brachial plexus block according to patient preference. The primary outcome was overall patient satisfaction assessed within 24 h postoperatively. Secondary outcomes included block performance time, waiting time, total anesthesia-related time, intraoperative and postoperative pain scores, additional sedation requirements, postoperative numbness, willingness to choose the same anesthetic technique again, safety outcomes and surgeon satisfaction. Results: Overall patient satisfaction was significantly higher in the peripheral nerve block group compared with the WALANT group (median [IQR]: 90 [85–100] vs. 80 [70–90], p < 0.0001). Intraoperative and postoperative pain scores were also significantly lower in the peripheral nerve block group. Although block performance time was longer with the peripheral nerve block, waiting time and total anesthesia-related time were significantly shorter compared with WALANT. Surgeon satisfaction and the need for additional intraoperative sedation did not differ significantly between groups. Conclusions: In elective hand and forearm surgery, ultrasound-guided supraclavicular peripheral nerve block was associated with higher patient satisfaction, lower pain scores, and shorter total anesthesia-related time compared with WALANT. Surgical satisfaction scores were similar with both anesthetic techniques. Considering the heterogeneity of clinical settings and procedural requirements, as well as cost and resource utilization considerations, anesthetic technique selection should be individualized. Full article

Background/Objectives: An Aneurysmal Bone Cyst (ABC) is a rare benign osteolytic bone lesion with locally destroying growth. It occurs mostly in the first two decades of life, rarely in older patients, and commonly affects the metaphysis. Clinical presentation includes pain and pathologic fractures. While most ABCs occur as primary lesions, there is an entity of secondary (reactive) ABC following osseous lesions such as fractures. We report a rare case of a secondary aneurysmal bone cyst of the distal radius following a distal radius fracture 4 years prior, with subsequent treatment and reconstruction. Methods: A 67-year-old female patient presented with a pathologic distal forearm fracture with radiologically expansive lytic bone lesion of the metaphysis of the distal radius, suspicious of an ABC. A biopsy and primary fracture management with an external fixator were performed due to the unclear dignity of the lesion. The diagnosis of an ABC was confirmed in the biopsy. The tumor resection and reconstruction were performed with a vascularized free fibula graft (ipsilateral, double barrel), using patient-specific 3D-printed osteotomy templates. Results: Follow-up radiographs showed excellent bone union with progressive remodeling. The functional outcome was very good with almost the same range of motion and grip strength as the contralateral side. No limitation in everyday life and no donor site morbidity was reported. Conclusions: ABC is a rare benign bone tumor the treatment of which consists of complete resection and reconstruction. Reconstruction of the distal radius can be achieved with a fibula graft. In our case, an excellent result was achieved with patient-specific osteotomy templates. Only a few cases of ABC in the distal radius and at this age have been reported; nevertheless, it should be considered as a differential diagnosis for osteolytic bone lesions Full article

Objectives: The aim of this case report is to highlight the diagnostic challenges of carotid space masses, share clinical experience, and educate clinicians by presenting a case of a rare disease. Introduction: Accessory nerve schwannomas are rare, benign peripheral nerve sheath tumors. They make up only a small percentage of all cervical schwannomas. Given their rarity and varying appearance on imaging, these tumors can be difficult to accurately diagnose. Schwannomas may mimic other carotid space pathologies, such as metastatic lymphadenopathy, paragangliomas, or sympathetic chain tumors. Accurately identifying the nerve of origin before surgery is important for effective surgical planning and neurological function protection. Case Description: A 50-year-old woman presented with an asymptomatic left-sided neck mass. Computed tomography (CT) revealed a cystic lesion with a thick, contrast-enhancing capsule in the left carotid space, causing internal jugular vein compression and partial thrombosis. Subsequent MRI showed a 28 mm × 23 mm × 38 mm well-defined mass with characteristic schwannoma features, including T2/Short tau inversion recovery (STIR) hyperintensity, peripheral enhancement, central cystic degenerative components, and peripheral diffusion restriction with corresponding lower apparent diffusion coefficient (ADC) values. Split-fat sign and fascicular sign were also seen on the MRI. Despite these imaging findings, the radiological interpretation suggested a sympathetic chain schwannoma as the most likely diagnosis. The correct diagnosis of accessory nerve schwannoma was established intraoperatively when the mass was visualized to be attached to the accessory nerve. Conclusions: This case highlights that even with suggestive MRI features, the rarity of accessory nerve schwannomas can lead to misidentification of the nerve of origin. Accurate diagnosis may require intraoperative visualization, thus marking the importance of including accessory nerve involvement in the differential diagnosis of carotid space masses. Full article

Background/Objectives: The identification of peripheral nerves is critical for their preservation during surgery, as accidental transection or injury can lead to significant patient morbidity. Current methods for identifying nerves typically rely on qualitative white-light visualization of anatomy, texture, and color. To improve nerve identification during surgical procedures, we developed a novel nerve imaging agent, “bevonescein,” a derivative of the peptide–dye conjugate FAM-HNP401. Methods: Variants of FAM-HNP401 were designed to be synthesized completely on solid phase to enable the efficient generation of GMP (Good Manufacturing Practice)-qualified bevonescein. We determined the nerve binding affinity for each variant, CPC-17, CPC-18, CPC-19 (bevonescein), and CPC-20, using mean fluorescent intensity measurements after binding the agents to human sural nerve sections. Results: Bevonescein (CPC-19) demonstrated significantly superior nerve binding compared to other variants and controls. Bevonescein-labeled nerves exhibited a mean fluorescent intensity of 562 ± 34.7, compared to 252 ± 41.7 for CPC-17, 344 ± 34.7 for CPC-18, and 270 ± 41.7 for CPC-20. The dye-alone control, 5-carboxyfluorescein, showed a fluorescent intensity of 168 ± 41.4. Conclusions: Bevonescein represents a first-in-class molecule that can improve the visualization of peripheral nerves during surgery, potentially reducing nerve injury and associated morbidity. It has been successfully tested in a Phase 1/2 clinical trial demonstrating safety and efficacy at a 500 mg dose and is currently in Phase 3 clinical testing. Full article

Background: Targeted muscle reinnervation (TMR) is increasingly used to enhance prosthetic control and to reduce post-amputation pain. Its implementation across new centers raises questions about the reproducibility of outcomes and the impact of surgical experience. Methods: We compared the first three TMR patients treated in a newly established center in Nantes, France, with three patients treated in a high-volume center in Göttingen, Germany. Functional outcomes were measured using the Box and Block test (BBT), and operative time was recorded. Two French cases were performed with the assistance of a Göttingen-based surgeon. Conclusions: The functional outcomes showed a similar trend in both groups. The mean BBT scores were equivalent, suggesting reliable reinnervation and prosthetic integration even in early cases. Operative times were longer in Nantes, but did not impact outcomes. TMR appears not to have a pronounced learning curve, particularly regarding functional success in early cases under guided protocols. Factors such as assistance from experienced surgeons and favorable donor-to-recipient nerve ratios likely contribute to consistent outcomes. These findings support the reproducibility of TMR across institutions. Results: Within the first two years of rehabilitation we observed improvements in both functional performance and patient-reported quality of life. All six patients across both centers in-creased in BBT scores. All the patients reported an increase in social relationships and psychological health, and two of three patients reported an increase in physical health. Importantly, all six patients discontinued the use of pain medication at 2 years fol-lowing TMR. Furthermore, the French patients reported a decrease from 65–82 mm to 0–31 mm across the patients’ Visual Analog Scale (VAS) pain scores. Full article

Background: Achieving adequate margins in pelvic bone tumor resection remains difficult, as conventional navigation provides no direct three-dimensional margin feedback. We proposed an innovative dangerous region generation method based on 3D image resampling and anisotropic distance transform, integrated with computer-assisted navigation, to enhance surgical margin accuracy. This study aimed to evaluate its oncological safety, functional outcomes, and perioperative efficacy in pelvic tumor surgery. Methods: The study was conducted on 19 patients (8 males, 11 females) with primary pelvic bone tumors between May 2018 and June 2024. The age range was 19 to 66 years (mean age: 62.67 years). Histological diagnoses included chondrosarcoma (n = 6), giant cell tumor (n = 4), osteosarcoma (n = 1), chordoma (n = 2), Ewing sarcoma (n = 3), spindle cell sarcoma (n = 1), chondromyxoid fibroma (n = 1), and peripheral nerve sheath tumor (n = 1). The feasibility of the dangerous region generation method for computer-assisted pelvic tumor resection surgery was assessed by general results, oncological and functional results. Results: All patients successfully underwent surgery with a mean operative time of 252 min and average intraoperative blood loss of 1358 mL. The mean hospital stay was 22 days, and all patients completed follow-up (mean, 37 months). Two patients developed postoperative wound complications, which resolved after debridement. Adequate surgical margins were achieved in all cases. The 5-year overall survival rate was 75.6%, increasing to 80.0% among patients with wide-margin resections. At the final follow-up, the mean MSTS score among 16 limb-salvage patients was 26.6, corresponding to an average functional recovery of 88.5%. Most patients exhibited a normal gait and were able to ambulate without assistive devices. Conclusions: This dangerous region generation method, when combined with computer-assisted techniques for pelvic bone tumor resection, is feasible and can achieve favorable clinical outcomes. Full article

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment disorder, with a lifetime prevalence estimated at approximately 10%. This narrative review explores the historical evolution, current management strategies, and emerging trends in CTS diagnosis and treatment. Early recognition of CTS led to the development of conservative interventions, including splinting, corticosteroid injections, and physical therapy, aimed at alleviating median nerve compression and associated symptoms. The advent of open carpal tunnel release established surgery as the definitive treatment for moderate-to-severe CTS, with subsequent refinements—such as mini-open and endoscopic techniques—focused on minimizing tissue trauma and expediting recovery. Comparative studies demonstrate similar long-term efficacy between surgical modalities, though endoscopic approaches often provide faster short-term recovery. Advances in diagnostic imaging, including high-resolution ultrasound, have improved early detection and dynamic assessment of median nerve compression. Emerging therapies, such as regenerative biologics, neuromobilization, and minimally invasive surgical innovations, offer promising adjuncts to current care. Despite substantial progress, further research is needed to clarify optimal patient selection, refine minimally invasive techniques, and explore regenerative interventions. This review underscores the importance of individualized, evidence-based, and patient-centered approaches to CTS management, integrating both established and emerging strategies to optimize functional outcomes and quality of life. Full article

Background: Carpal tunnel syndrome (CTS) is a common peripheral neuropathy with increasing prevalence and economic burden. This study aimed to analyze recent trends in CTS treatment patterns, healthcare utilization, and costs within the dualized healthcare system in Korea, using nationwide claim data. Methods: This cross-sectional study used data from the Korean Health Insurance Review and Assessment Service National Patient Sample (HIRA-NPS) between 2010 and 2017. Patients with a primary diagnosis of CTS (KCD-10: G56.0) were included. Descriptive analyses were performed to examine trends in patient characteristics, healthcare utilization, treatment patterns, and medical costs in Western and Korean medicine. Results: A total of 29,112 patients with CTS were analyzed. In Western medicine, diagnostic tests accounted for the highest expenditure, particularly X-ray, nerve conduction studies, and electromyography. Over time, X-ray utilization increased, while nerve conduction and electromyography tests decreased. The proportion of surgical treatment declined from 11.28% in 2010 to 8.55% in 2017, whereas Korean medicine use increased from 9.41% to 15.08%, mainly consisting of acupuncture and related procedures. Conclusions: Korea exhibited a lower CTS surgery rate than other countries, alongside a rising trend in Korean medicine utilization. These findings underscore the distinctive dual healthcare system in Korea and highlight the need for prospective studies to assess the long-term effectiveness of Korean medicine-based conservative treatments. Additionally, the results may inform national health policy decisions, including insurance coverage and resource allocation for CTS management. Full article

Migraine is a prevalent and disabling neurological disorder with multifactorial origins and complex clinical manifestations. While pharmacologic therapies remain the cornerstone of management, a growing body of evidence highlights the role of extracranial peripheral nerve compression as a significant contributor to migraine pathophysiology in selected patients. This recognition has expanded the therapeutic role of plastic surgery, offering anatomically targeted interventions that complement or surpass traditional medical approaches for refractory cases. From a plastic surgeon’s perspective, optimal migraine care begins with accurate identification of clinical patterns, trigger-site mapping, and the judicious use of diagnostic tools such as nerve blocks and botulinum toxin. Surgical decompression techniques, including endoscopic and open approaches, address compression of the supraorbital, supratrochlear, zygomaticotemporal, greater and lesser occipital, auriculotemporal, and intranasal contact-point trigger sites. Adjunctive strategies such as autologous fat grafting further enhance outcomes by providing neuroprotective cushioning and modulating local inflammation through adipose-derived stem cell activity. Recent advances, including neuromodulation technologies, next-generation biologics, and innovations in surgical visualization, underscore the ongoing shift toward precision-based, mechanism-driven therapy. As understanding of migraine heterogeneity deepens, the integration of surgical expertise with modern neuroscience offers a comprehensive and personalized therapeutic framework. Plastic surgeons, equipped with detailed knowledge of peripheral nerve anatomy and minimally invasive techniques, play an increasingly pivotal role in the multidisciplinary management of refractory migraine. Full article

Background/Objectives: Facial nerve injury from conditions such as Bell’s palsy, trauma, surgery, and infection leads to facial asymmetry and motor deficits. Axotomy models reproduce peripheral nerve disruption and consequent motor impairment. To compare the effects of forward versus reverse autologous nerve suturing on neural regeneration and motor recovery within the facial nucleus after axotomy. Methods: In rats subjected to facial nerve axotomy, motor recovery was assessed at 8 weeks using whisker movement and blink reflex tests. Immunohistochemistry quantified choline acetyltransferase (ChAT), sirtuin 1 (SIRT1), and Iba-1 as indices of cholinergic function, cellular stress/inflammation modulation, and microglial activation in the facial nucleus. Results: Axotomy significantly reduced whisker and blink scores compared with sham. Both forward and reverse suturing significantly improved these behavioral outcomes versus axotomy. Within the facial nucleus, axotomy decreased ChAT- and SIRT1-positive cells and increased Iba-1 expression, while both suturing techniques increased ChAT and SIRT1 and reduced Iba-1. These changes suggest enhanced cholinergic function, mitigation of stress/inflammatory responses, and attenuation of microglial activation following repair. Conclusions: Forward and reverse suturing were each associated with improved motor function and favorable molecular and cellular changes in the facial nucleus after facial nerve axotomy. These findings support the utility of surgical repair irrespective of graft orientation and highlight involvement of key pathways—cholinergic signaling, SIRT1-related regulation, and microglial activity—in nerve restoration. This work extends our previous study, which focused on peripheral nerve regeneration after forward and reverse suturing, by elucidating how graft orientation affects central facial nucleus responses. By integrating behavioral outcomes with ChAT, Iba-1, and SIRT1 expression, the present study provides novel insight into the central mechanisms underlying motor recovery after facial nerve repair and helps explain why comparable functional outcomes are achieved regardless of graft polarity. Full article

Neuropathic pain represents a critical challenge in medical research and clinical practice. Enhanced peripheral nerve activity and spinal dorsal horn neuronal firing are thought to contribute to the nociceptive hypersensitivities that are observed in chronic pain conditions, including those modeled by partial sciatic nerve ligation (PSNL). However, the detailed in vivo neuronal response dynamics and underlying mechanisms in the PSNL model remain to be fully clarified. To better understand these mechanisms, we evaluated dorsal root ganglion (DRG) and spinal dorsal horn neuronal activity in the PSNL model using in vivo approaches. Von Frey testing revealed sustained mechanical allodynia in PSNL animals; withdrawal thresholds were significantly reduced up to day 14 post-surgery. Immunohistochemistry revealed a stimulation-dependent increase in phosphorylated extracellular signal-regulated kinase (pERK)-positive neurons in the DRG, thereby indicating heightened peripheral nerve activity. Additionally, electrophysiological recordings demonstrated the enhanced firing of spinal dorsal horn neurons in response to the same stimuli. Notably, DRG pERK expression changes correlated with spinal neuronal firing frequency. Together, these findings suggest that peripheral nerve activity drives spinal neuronal sensitization, thus elucidating both pain mechanisms in the PSNL model and activity-dependent signaling in neuropathic pain. Full article

Background: Proximal–distal orientation of nerve autografts (graft polarity) is an important consideration in peripheral nerve repair, but the literature is inconsistent on whether reversing graft polarity improves regeneration. With these disparities, we aimed to systematically review the effect of forward (normal proximal-to-distal) vs. reversed graft orientation on peripheral nerve regeneration or functional outcomes. Methods: We conducted a comprehensive search of PubMed, Scopus, Cochrane Library, EMBASE, and Google Scholar (January 1978–August 2025) for studies comparing autograft polarity in nerve regeneration. Of 90 articles identified, 9 studies met inclusion criteria (comparative studies directly evaluating graft orientation). Data on nerve conduction and functional recovery outcomes were extracted, and random-effects meta-analyses (using Hedges’ g standardized mean differences) were performed to compare forward vs. reversed graft orientation, with heterogeneity assessed by I² and τ². Results: The nine included studies (all in animals) assessed histological, morphometric, electrophysiological (e.g., nerve conduction velocity, action potential amplitude), behavioral and functional outcomes. Three of the nine studies reported a significant outcome difference favoring one graft orientation, whereas six studies found no significant difference. Meta-analysis of five studies reporting nerve conduction velocity found no overall difference between forward and reversed orientation (Hedges’ g = −0.57, 95% confidence interval −1.52 to 0.37; p = 0.23; I² = 82.96%, τ² = 0.935). Conclusions: This meta-analysis provides the first quantitative synthesis of experimental evidence assessing the impact of nerve autograft orientation, revealing no consistent advantage of forward or reversed polarity on regeneration outcomes. Although based on limited and heterogeneous animal data, the findings clarify existing trends and highlight areas for further experimental and clinical research. Full article

Malignant peripheral nerve sheath tumors (MPNSTs) are one of the most difficult sarcomas to treat. Due to the rarity of MPNSTs, many of the therapeutic approaches used are from treatment guidelines for soft tissue sarcoma. Besides surgery, little success has been achieved using these therapies. Traditional chemotherapy and radiation therapy regimens designed to treat sarcoma have unclear efficacy when used to treat MPNSTs. Targeted therapeutics that succeeded in other sarcomas failed to produce positive results in MPNSTs. Moreover, investigational agents that have shown efficacy in preclinical models have produced disappointing outcomes in clinical trials. While therapeutic options for patients with MPNST have remained relatively stagnant, dramatic improvements in therapeutic outcomes of other rare sarcomas have been made. This difference in success is likely caused by the complex heterogeneity of MPNSTs that hinders drug development, although many MPNSTs are associated with neurofibromatosis type 1 (NF1), a genetic disorder resulting from mutations in the NF1 gene that encodes the negative RAS regulator neurofibromin. The development of new agents for MPNST treatment has shifted away from solely targeting RAS pathway gene products to stimulating the immune system and manipulating other MPNST driver mutations such as CDKN2A/B, SUZ12, EED, and TP53. This review presents recent advances in the treatment of sarcomas and the future of drug development targeting MPNSTs. Full article