Neuromuscular ultrasound and nerve conduction studies as complementary tools for screening of diabetic peripheral neuropathy.

Tarsal tunnel syndrome is an entrapment neuropathy caused by the compression of the tibial nerve and its terminal branches in the tarsal tunnel. Electrophysiological examinations are often used to diagnose tarsal tunnel syndrome. Surgical decompression of the tibial nerve is performed in patients who are resistant to conservative treatment. However, the preoperative electrophysiological findings that predict surgical outcomes remain unknown. This study aimed to clarify the preoperative electrophysiological findings that predict the surgical outcomes of tarsal tunnel syndrome. We reviewed 28 feet of 23 patients who underwent preoperative electrophysiological examinations between November 2021 and October 2024, were diagnosed with tarsal tunnel syndrome, and subsequently underwent surgery. Electrophysiological examinations included nerve conduction study and needle electromyography. We reviewed patient characteristics and electrophysiological findings prior to surgery. Sensory plantar symptoms, such as numbness and pain, were evaluated using the Numerical Rating Scale before and after surgery. Patients were divided into the improvement and non-improvement groups based on the Numerical Rating Scale improvement rate after surgery. A comparative analysis of patient characteristics and preoperative electrophysiological findings was performed between the improvement and non-improvement groups. In a motor nerve conduction study of the tibial nerve, the amplitude of the compound motor action potential evoked by stimulation at the ankle was significantly lower in the non-improvement group than in the improvement group. In tarsal tunnel syndrome, a low compound motor action potential amplitude of the tibial nerve on preoperative motor nerve conduction study may indicate poor symptomatic improvement after surgery. Electrophysiological examinations may be useful for predicting the surgical outcomes of tarsal tunnel syndrome.

Background/Objectives: The popliteus muscle (PM) plays a crucial role in stabilizing the posterolateral aspect of the knee. However, its layered structure and innervation are not well understood due to its location, size, and proximity to neighboring anatomical features. This study aimed to clarify the layered morphology, intramuscular innervation, and fiber-type composition of the PM, providing anatomical insights for clinical interventions. Methods: We examined 32 lower extremities from sixteen formalin-embalmed cadavers using a multimodal approach that included gross dissection, Sihler’s staining, ultrasonography, and histochemical analysis. Results: On average, 2.8 ± 1.1 branches of the tibial nerve entered the PM, with a consistently high-density entry zone located at 56–64% of the muscle length. Sihler’s staining and ultrasonographic analyses revealed a distinct separation between the superficial and deep layers across the central tendon, each exhibiting compartmentalized intramuscular branching territories. The superficial layer was primarily composed of type IIx fibers and exhibited a larger pennation angle, while the deep layer was richer in type IIA fibers with a smaller pennation angle. These findings illustrate that the PM functions as a dual motor unit rather than a uniform structure. Conclusions: The PM exhibits a distinct compartmentalized organization, functioning as a multifunctional motor unit. The identification of specific intramuscular entry zones and the organization of muscle layers provide strong anatomical evidence for improved targeting in neuromuscular-modulating interventions. This enhances the precision, safety, and efficacy of clinical strategies aimed at addressing posterior knee stability and pathologies related to the posterolateral complex (PLC).

Postpartum pelvic floor dyssynergic defecation (PFDD) is a common and distressing condition. We hypothesized that transcutaneous tibial nerve stimulation (TTNS) combined with standard rehabilitation would be superior to rehabilitation alone for alleviating symptoms in primiparous women with PFDD. In this randomized controlled trial, 40 primiparous women with PFDD were allocated to an intervention group (TTNS + standard rehabilitation, n = 20) or a control group (sham stimulation + standard rehabilitation, n = 20). The intervention lasted 6weeks. Primary (constipation symptom score) and secondary outcomes (clinical efficacy, pelvic floor surface electromyography) were assessed at baseline and post-treatment. Both groups improved significantly after treatment (p < 0.05). However, the intervention group demonstrated a significantly greater reduction in constipation symptom scores (p < 0.05) and a higher overall clinical effectiveness rate (90% vs. 65%, p < 0.05). Pelvic floor surface electromyography showed significantly greater improvement in the intervention group for resting, fast, and slow contraction phases (p < 0.05), but not for endurance (p > 0.05). TTNS is an effective adjunct to standard rehabilitation for improving constipation symptoms and pelvic floor muscle function in primiparous women with PFDD. It represents a valuable, non-invasive therapeutic option for this condition.This study demonstrates positive effects of transcutaneous tibial nerve stimulation as an adjunctive therapy for primiparous women with postpartum pelvic floor dyssynergic defecation. It significantly improves constipation symptoms, clinical effectiveness rates, and key parameters of pelvic floor muscle function compared to standard rehabilitation alone. Given its non-invasive nature, favorable safety profile, and demonstrated clinical benefits,TTNS represents a valuable addition to the therapeutic options for this common postpartum condition.

To estimate the added clinical benefit of extending transcutaneous tibial nerve stimulation (TTNS) from 12 to 24 weeks in pediatric overactive bladder (OAB), and to characterize late responders. Prospective single-arm cohort with home-based TTNS and assessments at baseline, 12, and 24 weeks. The primary outcome was change in OAB Symptom Score (OABSS) and responder status defined by a minimal clinically important difference (MCID) of≥3 points. Paired responder transitions were tested with McNemar's exact test and summarized as paired risk difference (RD) with 10,000-sample bootstrap 95% CIs; repeated-measures GEE/LMM were pre-specified for confirmatory modeling. Among 80 paired observations, 12→24-week transitions were 0→0: 13, 0→1: 14, 1→0: 0, 1→1: 53. The paired RD in responder rate (24w-12w) was 0.175 (95% CI 0.100-0.263; McNemar p=0.000122). Late response occurred in 14 of 27 (51.9%) 12-week nonresponders. Mean OABSS improved by 3.64±2.25 at 12 weeks and 5.14±2.63 at 24 weeks. Extending TTNS to 24 weeks was associated with additional symptom improvement and a substantial proportion of late responders without loss of response. Findings suggest that continuing TTNS beyond 12 weeks may be considered for early nonresponders, pending confirmation in randomized, sham-controlled trials.

Vasculitic neuropathy (VN) is a disease in which vessel inflammation happens and injures peripheral nerves. Despite increasing awareness, features of VN in mainland China are still understudied. To characterize the clinical, pathological features and outcomes of VN in mainland China, and evaluate clinicopathological correlations: METHODS: We retrospectively reviewed records of VN patients diagnosed pathologically between June 1999 and December 2024, including demographic data, clinical manifestations, biopsy features, and outcomes. 112 patients were totally included. All presented with axonal sensorimotor neuropathy, most commonly involving the tibial (90.63%) and peroneal (87.50%) nerves. Systemic VN (SVN) showed more frequent transmural inflammatory cell infiltration (ICI) than non-systemic VN (NSVN) (p = 0.046). Eosinophilic granulomatosis with polyangiitis (EGPA) was more common in VN without ICI than VN with ICI (p = 0.008). In SVN, the ICI-positive exhibited more severe distal upper limb weakness (p = 0.042) and higher thrombosis rates (p = 0.001) than ICI-negative. Of the 63 patients followed, 62 received glucocorticoids with or without immunosuppressants. Thirteen died from multi-organ complications (12 SVN and 1 NSVN), while others achieved remission. The 5-year all-survival rate was 80.23% (95% CI 66.83%- 88.66%). This first large cohort of VN in mainland China delineates its clinical-pathological features. EGPA showed a lower diagnostic yield on biopsy, suggesting diverse mechanisms of vascular injury. Nerve biopsy remains the diagnostic gold standard. The overall prognosis of VN is relatively favorable, emphasizing the need for early recognition and treatment.

Leprosy is a chronic granulomatous disease that commonly affects the peripheral nervous system, often leading to significant disability. High-resolution ultrasonography has emerged as a promising tool for the noninvasive assessment of nerve involvement in leprosy. To figure out the diagnostic value of HRUS in assessing peripheral nerve involvement in leprosy, with a focus on measuring the cross-sectional area (CSA) of major nerves. A systematic search of PubMed, Scopus, Web of Science, and Embase was conducted up to 2024. Seventeen studies were included, and quality assessment was performed using NIH and NOS tools. Meta-analyses compared CSA of the ulnar, median, posterior tibial, and common fibular nerves between patients with leprosy and healthy controls. Heterogeneity was evaluated using the I2 statistic and sensitivity analyses were performed. Patients with leprosy showed significantly increased CSA in all examined nerves compared with controls. Single-arm analysis of CSA in patients with leprosy showed consistent nerve enlargement, particularly in the ulnar nerve. Our review shows the usefulness of HRUS as a sensitive, noninvasive imaging modality for evaluating peripheral nerve involvement in leprosy.

Nocturnal closed-loop transcutaneous tibial nerve stimulation: a cardio-urologic hypothesis to interrupt the bladder–heart arousal axis and extend life in older adults

A0188 Transcutaneous Posterior Tibial Nerve Stimulation (TPTNS) for refractory overactive bladder symptoms in pediatric patients: A subgroup analysis in the Philippine setting

Neuroinflammation and metabolic dysfunction drive nerve conduction deficits in diabetic neuropathy: Clinical and in silico insights.

During dissection of an adult female cadaver, an unique variation of the plantaris muscle was noted in the right lower limb. The plantaris had two heads of origin. The lateral head was fleshy and the medial head was aponeurotic. The lateral head took origin from the lateral supracondylar line. The medial aponeurotic head took origin from the capsule of the knee joint, oblique popliteal ligament and the fascia covering popliteus muscle. The two heads joined each other behind the main neurovascular bundle and the narrow gap between these two heads was traversed by tibial nerve, popliteal vein and popliteal artery. The tendon of plantaris divided into medial and lateral slips. The medial slip merged with the anterior surface of the tendocalcaneus and the lateral slip merged with the deep fascia, lateral to the insertion of the tendocalcaneus.

Our objective is to conduct a screening for motor neuropathy in children and adolescents with type 1 diabetes to assess its point prevalence and to analyse potential risk factors associated with any positive motor neuropathy diagnosis. This is a cross-sectional study involving children aged 12 to 18 years who have been diagnosed with diabetes for five or more years and are receiving treatment with an insulin pump. All participants underwent a neurological examination and were questioned about symptoms of neuropathy. A nerve conduction study was conducted to evaluate the median, ulnar, common peroneal, and tibial motor nerves. Sensory nerves were also examined. The F-wave response of the tibial nerve was analysed, and needle electromyography was performed on a proximal and distal muscle of the lower limb. A total of 29 children completed the study (mean age: 15.34 ± 1.56 years; mean duration of diabetes: 11.93 ± 2.84 years; HbA1c levels: 7.50 ± 1.17%). Results were normal, indicating adequate motor nerve integration and excluding the presence of motor neuropathy as well as peripheral neuropathy, even at subclinical level. In our studied population, which receives tight monitoring and support for diabetes management, using nerve conduction studies to detect early subclinical motor neuropathy shows no clear benefit. This finding was consistent even among individuals with poor metabolic control, altered albumin/creatinine ratio, and diabetes duration over 10 years, with no abnormalities observed. We recommend following the latest guidelines provided by the American Diabetes Association (ADA). The online version contains supplementary material available at 10.1007/s40200-026-01865-z.

Introduction: Tarsal tunnel syndrome (TTS) is a compressive neuropathy involving the posterior tibial nerve or its branches within the fibro-osseous tarsal tunnel. Vascular etiologies are underrecognized and may be overlooked in clinical assessment. Objective: To illustrate the diagnostic value of dynamic ultrasound in identifying clinically significant neurovascular compression in TTS. Case report: A 32-year-old woman presented with right ankle pain associated with intermittent electric shock–like sensations over the medial plantar aspect of the foot, exacerbated by prolonged walking. Physical examination revealed a positive Tinel sign along the medial plantar nerve. Ultrasound demonstrated close contact between the posterior tibial artery and the medial plantar nerve without other structural abnormalities, suggesting neurovascular compression. Conclusion: Vascular causes of TTS should be considered in patients presenting with plantar neuropathic symptoms. High-resolution ultrasound with color Doppler plays a key role in identifying neurovascular conflict and guiding clinical management.

Early recognition of DPN gives physicians the opportunity to deliver appropriate treatment and counseling to minimize subsequent complications. This study aimed to evaluate the diagnostic performance of tibial nerve cross-sectional area (CSA) in detecting DPN using a Modified Toronto Clinical Neuropathy Score (mTCNS) ≥ 3 as the diagnostic reference in Thai diabetic patients. A total of 67 diabetic patients (120 limbs) were enrolled from Srinagarind Hospital between 2022 and 2023. A total of 120 limbs belonging to 67 patients were categorized into two groups: non-DPN group (mTCNS < 3) (n = 42) and DPN group (mTCNS ≥ 3) (n = 78). Tibial nerve CSA was measured 3 cm proximal to the medial malleolus using ultrasound. Clinical parameters and metabolic profiles were recorded. Receiver operating characteristic analysis, correlation analyses, and multivariable logistic regression were performed to evaluate diagnostic utility and associations between CSA and clinical parameters. The tibial nerve CSA was significantly higher in the DPN group (13.49 mm2, 95% CI: 12.84-14.13) compared to the non-DPN group (11.98 mm2, 95% CI: 10.95-13.02) (p = 0.015). A CSA threshold of 13 mm2 yielded a sensitivity of 58.5% and specificity of 74.2%. CSA positively correlated with mTCNS (r = 0.49, p < 0.001) and sensation score (r = 0.37, p = 0.002) in DPN patients. Logistic regression identified CSA and estimated glomerular filtration rate as independent predictors of DPN status. Tibial nerve CSA may serve as a useful structural marker to support the identification of DPN. When used alongside established clinical assessments, CSA measurement could contribute to earlier detection and improved risk stratification in diabetic populations.

Background/Objectives: Posterior tarsal tunnel syndrome is a compressive neuropathy of the tibial nerve at the level of the ankle within the tarsal tunnel. However, there is no established gold standard for the diagnosis of tarsal tunnel syndrome to date. High-resolution ultrasound could add important value in this setting. But up to date, to the best of our knowledge, only six clinical studies have investigated the use of ultrasound for the diagnosis of tarsal tunnel syndrome, with partially conflicting results. Most authors identify nerve swelling at the level of anatomical compression as the key ultrasonographic criterion, whereas at least one study and some expert opinions instead emphasize nerve compression at the site of entrapment. Methods: We performed a retrospective observational study of high-resolution ultrasound of the tibial nerve in patients with typical clinical and electrophysiological characteristics of tarsal tunnel syndrome. Results: A cohort of 26 feet with clinically and electrophysiologically confirmed tarsal tunnel syndrome was collected. Nerve ultrasound demonstrated a moderate sensitivity of 65% for the detection of abnormalities of the tibial nerve when applying the commonly used cut-off of 11.8 mm2 for the tibial nerve at the level of the tarsal tunnel entry or within the tarsal tunnel. In all but one of the cases classified as pathological on ultrasound, an increase in tibial nerve CSA in the tarsal tunnel was observed compared with the CSA measured 5-10 cm proximal to the tarsal tunnel entry (by a factor of 1.6 ± 0.53). A secondary cause was found in only 12% of the cases. But this study also suggests that ultrasound may remain unremarkable in approximately one third of patients with tarsal tunnel syndrome. Conclusions: Establishing the diagnosis of tarsal tunnel syndrome remains challenging. Our study supports the hypothesis proposed in previous publications that tarsal tunnel syndrome appears to be an exception among compression neuropathies on ultrasound: sonography demonstrates nerve swelling not proximal to the site of compression, but at the level of the anatomical compression. Further prospective data would be of substantial clinical relevance.

Fecal incontinence (FI) is a condition characterized by the involuntary loss of stool, resulting from the inability to control the sphincter and neuromuscular mechanisms responsible for continence. Percutaneous electrical stimulation of the posterior tibial nerve (posterior tibial nerve stimulation-PTNS) has been used as a therapeutic alternative in the treatment of FI. The objective of this study was to investigate the efficacy. A systematic review was conducted according to the recommendations and criteria described in the PRISMA (Preferred Reporting Guide to Systematic Reviews and Meta-Analyses) items and in the Cochrane Manual. Experimental studies that evaluated the effects of posterior tibial nerve electrostimulation in adult patients with fecal incontinence were included. Case reports, literature reviews, and gray literature were excluded. The search was performed in the MEDLINE/PubMed, Cochrane Library, Scopus, Regional Portal of the VHL, Embase, CINAHL, and Web of Science databases. Seventeen studies were included, totaling 1248 participants. The average duration of treatment protocols was 12weeks, with predominantly weekly interventions. The most frequently used stimulation parameters included frequencies between 10 and 20Hz and pulse widths of 200μs. Most studies demonstrated a reduction of 50% or more in fecal incontinence episodes, as well as significant improvement in severity scores and quality of life. Randomized clinical trials presented a low risk of bias, while some observational studies demonstrated methodological limitations. PTNS is a minimally invasive intervention with a favorable safety profile and potential clinical applicability.

Autonomic nervous system (ANS) imbalance may contribute to functional pelvic disorders such as overactive bladder (OAB). Transcutaneous tibial nerve stimulation (TTNS) is a non-invasive therapy for OAB; however, its autonomic modulation mechanisms remain unclear. This exploratory study evaluated the acute effects of TTNS on ANS activity in healthy volunteers using heart rate variability (HRV) to model neuroautonomic pathways relevant to OAB. In this open-label, prospective, exploratory, single-arm study, 20 healthy volunteers (11 women; median age 31 years) underwent three 10-min phases: baseline rest, continuous submotor TTNS via surface electrodes on the left tibial nerve, and post-stimulation recovery. HRV was recorded using a Polar H10 sensor and analyzed with Kubios software. Time-domain (SDNN, RMSSD, pNN50), frequency-domain (LF, HF, LF/HF), and additional indices (PNS, SNS, Stress indices) were assessed in standardized 5-min windows. Friedman and Wilcoxon tests with Bonferroni correction were applied. A vagal-oriented composite response score (z-delta mean) was correlated with age and BMI (Spearman, permutation-based p values). Significant phase effects were observed for PNS index, SNS index, Stress index, SDNN, and RMSSD (p < 0.05). Post-hoc analyses confirmed increases in PNS index, SDNN, and RMSSD, and decreases in SNS and Stress indices during stimulation compared with baseline. Partial post-stimulation persistence was noted for SDNN and Stress index, although these changes did not remain significant after Bonferroni correction. The composite response score correlated negatively with age (ρ = -0.52; p = 0.019; permutation p = 0.016) and showed a non-significant positive trend with BMI (ρ = 0.38; p = 0.10). Acute TTNS enhances parasympathetic and suppresses sympathetic activity, with partially sustained effects after stimulation. Younger age predicts stronger vagal responsiveness, suggesting age-dependent neuromodulatory efficacy. Validation in OAB populations is warranted.

This study compared neuromuscular fatigue induced by an acute wide-pulse high-frequency session, either applied in an isometric condition (WPHF) or combined with muscle lengthening (WPHF+LEN). Fifteen participants completed two randomized sessions, which involved 30 stimulation trains (pulse duration: 1 ms; frequency: 100 Hz; duty cycle: 15s ON/15s OFF) applied to the posterior tibial nerve at low stimulation intensity (5-10% maximal voluntary contraction, MVC). In the WPHF session, the ankle joint was held at a reference angle (90°) while a 10° muscle lengthening was superimposed during the stimulation in the WPHF+LEN session. Before and after each session, MVC was measured along with neural (voluntary activation level, VAL) and muscular (potentiated twitch, Pt) changes. Torque-time integral (TTI) was recorded for each train and the total TTI (ƩTTI) was calculated. Results showed a comparable decrease in MVC torque after the two sessions (-7.8 ± 6.9% for WPHF and -9.4 ± 5.7% for WPHF+LEN, P < 0.001) associated with a significant reduction in Pt amplitude (P < 0.001) indicating muscular changes, while VAL remained unchanged. ƩTTI was not different between sessions (9600 Nm.s for WPHF, 9550 Nm.s for WPHF+LEN; P = 0.95). However, although TTI significantly decreased throughout the WPHF session, it was preserved during the WPHF+LEN session. These findings indicate a similar amount of neuromuscular fatigue after the two sessions, primarily attributed to muscular alterations. Nevertheless, the combination of WPHF stimulation with muscle lengthening appears advantageous for preserving torque production throughout the stimulation trains.

Pelvic floor dysfunction (PFD) is a frequent yet underrecognized complication of neurological disorders such as multiple sclerosis (MS), Parkinson's disease (PD), and stroke. Its multifactorial pathophysiology involves complex neural mechanisms affecting bladder, bowel, and sexual function, often resulting in decreased quality of life and psychosocial distress. This focused mini-review aims to synthesize current evidence on the pathophysiology, clinical features, and rehabilitation approaches for neurogenic PFD in major neurological conditions. A targeted literature search was performed in PubMed, Scopus, and Web of Science databases to identify clinical and experimental studies published between 1990 and 2025 addressing urinary and PFD in neurological populations. Special attention was given to rehabilitation-based interventions such as pelvic floor muscle training (PFMT), biofeedback, neuromuscular electrical stimulation (NMES), and percutaneous tibial nerve stimulation. Neurogenic PFD is highly prevalent, with up to 90% of MS patients, 60% of PD patients, and nearly half of stroke survivors experiencing urinary symptoms. Conservative rehabilitation, particularly PFMT combined with biofeedback and NMES, improves muscle function, reduces incontinence frequency, and enhances quality of life. However, standardized rehabilitation protocols are lacking, and adherence remains a major barrier. Evidence supports a multidisciplinary rehabilitation approach integrating PFMT and adjunct modalities for neurogenic PFD. Further large-scale randomized studies are required to establish standardized, evidence-based clinical guidelines.

BackgroundChronic ankle instability (CAI) affects approximately 46% of individuals after ankle sprains, disrupting ligaments, muscles, and joint receptors, and impairing postural control. Percutaneous tibial nerve stimulation (PTNS) is a minimally invasive neuromodulation technique that may enhance neuromuscular function. This study aimed to evaluate the acute effects of ultrasound-guided PTNS on postural control in individuals with CAI compared to healthy controls.MethodsThis non-randomized controlled study included 28 participants: 14 with CAI (mean age 22.85 ± 5.02 years; BMI 24.83 ± 4.28) and 14 healthy controls (mean age 21.86 ± 3.44 years; BMI 22.8 ± 3.29). CAI diagnosis was confirmed by scores <24 on the Spanish Cumberland Ankle Instability Tool. Postural control was assessed via force platform during single-leg stance with eyes open and closed at baseline, immediately post-intervention, and at 2, 24, and 48 h post-PTNS. PTNS delivered biphasic current (10 Hz, 250 µs pulse width) at maximum tolerable intensity for 1.5 min under ultrasound guidance. Controls received no intervention.ResultsBaseline postural control did not differ significantly between groups (p > 0.05). Post-PTNS, no significant intergroup differences were observed, except a reduction over time in anteroposterior center of pressure amplitude (ACPap) in the CAI group with eyes closed (p = 0.023). No significant intragroup changes occurred.ConclusionsAlthough PTNS did not produce general improvements in postural control, the reduction in anteroposterior sway with eyes closed suggests a targeted neuromodulatory effect. These preliminary results support further research into PTNS as a complementary approach for managing CAI.Trial registration: ISRCTN177653522.