BACKGROUND: Generalized joint hypermobility (GJH) can be the result of several hereditary connective tissue disorders, especially Ehlers-Danlos syndrome. Cerebrovascular manifestations are among the most common complications in this disorder, and understanding their extent can help better diagnosis and prevention of hazardous events. We investigated visual evoked potential (VEP) changes in patients with GJH and compared them with healthy individuals.
METHODS: Our case-control study included 90 patients who fulfilled the Beighton score (B score) for joint hypermobility and other 90 healthy participants. All of them went under VEP study, and the amplitude and latency of the evoked potential (P100) were compared to each other.
RESULTS: The Case group had significantly higher B score (7.18 ± 0.967 vs. 1.18 ± 0.712), P100 latency (110.23 ± 6.64 ms vs. 100.18 ± 4.273 ms), and amplitude (6.54 ± 1.26 mv vs. 6.50 ± 1.29 mv) compared with the Control group, but the difference was only significant regarding B score, and P100 latency (p-value <.0001). Moreover, both latency and amplitude of P100 had significantly positive correlations with the B score in the Case group (p-value <.0001), but such correlations were not found in the Control group (p-value = .059).
CONCLUSIONS: Our study could reveal VEP changes, especially significant P100 latency in GJH patients without previous neurologic or musculoskeletal disorders. Whether these changes are due to GJH itself or are predictive of inevitable neurologic disease or visual pathway involvement, particularly Multiple Sclerosis needs further investigation with longer follow-up periods.

OBJECTIVE: Nerve conduction studies (NCSs) are widely used to support the clinical diagnosis of neuromuscular disorders. The aims of this study were to obtain reference values for peroneal, tibial, and sural NCSs and to examine the associations with demographic and anthropometric factors.
METHODS: In 5099 participants (aged 40-79 years) without type 2 diabetes of The Maastricht Study, NCSs of peroneal, tibial, and sural nerves were performed. Values for compound muscle action potential (CMAP) and sensory nerve action potential amplitude, nerve conduction velocity (NCV), and distal latency were acquired. The association of age, sex, body mass index (BMI), and height with NCS values was determined using uni- and multivariate linear regression analyses.
RESULTS: Detailed reference values are reported per decade for men and women. Significantly lower NCVs and longer distal latencies were observed in all nerves in older and taller individuals as well as in men. In these groups, amplitudes of the tibial and sural nerves were significantly lower, whereas a lower peroneal nerve CMAP was only significantly associated with age. BMI showed a multidirectional association. After correction for anthropometric factors in the multivariate analysis, the association between sex and NCS values was less straightforward.
CONCLUSIONS: These values from a population-based dataset could be used as a reference for generating normative values. Our findings show the association of NCS values with anthropometric factors. In clinical practice, these factors can be considered when interpreting NCS values.

Background: Since diabetic generalized neuropathy affects peripheral nerves, the diagnosis of carpal tunnel syndrome (CTS) with conventional electrodiagnostic techniques (EDX) [onset latency of median sensory nerve action potential (SNAP) or distal latency of median compound muscle action potential (CMAP)] is controversial. The aim of this study is to investigate the diagnostic values of two other techniques including inching method and second lumbrical-interossei test in patients with diabetic polyneuropathy (DPN) as well as signs or symptoms of CTS. Methods: Fifteen patients (30 hands) with definite diagnosis of generalized peripheral neuropathy secondary to diabetes who developed signs and symptoms of CTS were participated. For diagnosis of CTS, sensory and motor median distal latencies were considered by nerve conduction study. In the next step, inching method and second lumbrical-interossei test were performed for all hands. Finally, sensitivity and specificity of two tests were calculated. Results: Mean age of participants was 53.87 ± 11.53 years. The sensitivity and specificity of inching method in this study were 95.65% and 85.71%, respectively, and for the second lumbrical-interossei test, they were 73.91% and 71.42%, respectively. Conclusion: Inching method was more sensitive and specific than second lumbrical-interossei test in diagnosis of CTS among patients with diabetic peripheral neuropathy. Moreover, the sensitivity of inching method was greater than specificity.

Peripheral neuropathy is a common complication of type 2 diabetes mellitus (T2DM) that results in nerve conduction abnormalities. This study aimed to investigate the parameters of nerve conduction in lower extremities among T2DM patients in Vietnam. A cross-sectional study was conducted on 61 T2DM patients aged 18 years and older, diagnosed according to the American Diabetes Association\'s criteria. Data on demographic characteristics, duration of diabetes, hypertension, dyslipidemia, neuropathy symptoms, and biochemical parameters were collected. Nerve conduction parameters were measured in the tibial and peroneal nerves, including peripheral motor potential time, response amplitude M, and motor conduction speed, as well as sensory conduction in the shallow nerve. The study found a high rate of peripheral neuropathy among T2DM patients in Vietnam, with decreased conduction rate, motor response amplitude, and nerve sensation. The incidence of nerve damage was highest in the right peroneal nerve and left peroneal nerve (86.7% for both), followed by the right tibial nerve and left tibial nerve (67.2% and 68.9%, respectively). No significant differences were found in the rate of nerve defects between different age groups, body mass index (BMI) groups, or groups with hypertension or dyslipidemia. However, a statistically significant association was found between the rate of clinical neurological abnormalities and the duration of diabetes (p < 0.05). Patients with poor glucose control and/or decreased renal function also had a higher incidence of nerve defects. The study highlights the high incidence of peripheral neuropathy among T2DM patients in Vietnam and the association between nerve conduction abnormalities and poor glucose control and/or decreased renal function. The findings underscore the importance of early diagnosis and management of neuropathy in T2DM patients to prevent serious complications.

Background There are many physiological changes that accompany aging. Slowing of muscle contraction, alteration of muscle metabolism and neuromuscular junction, and reduction of nerve conduction velocity (NCV) are among these physiological changes. The present study was conducted to elucidate the effect of physiological factors like gender, height, and Body Mass Index (BMI) on motor and sensory nerve conduction study (NCS) of the upper limb and find out the normal data for healthy elderly subjects in central India. Methods A cross-sectional study among 382 healthy adult participants of central India aged 60 years and above. The study was carried out in the department of Physiology, Acharya Vinoba Bhave Rural Hospital, Wardha, India, from July 2017 to June 2022. An NCS was performed using the Neuron Spectrum 5 machine (Neurosoft, Ivanovo, Russia). A Microsoft Excel spreadsheet (Microsoft Corporation, Redmond, Washington, United States) was used to tabulate the information gathered. For statistical analysis, IBM SPSS Statistics for Windows, Version 22.0 (Released 2013; IBM Corp., Armonk, New York, United States) was used. Results All NCS parameters were greater in males as compared to females. As age advances, longer distal motor latency (DML) and F-wave minimum latency, decreasing amplitude, and slowing of conduction velocity (CV) were observed. As height increases, increasing DML and F-wave minimum latency, decreasing amplitude, and slowing of CV were observed. Higher BMI was found to be associated with lower amplitudes and slowing of CVs. Conclusion Age and height have a negative influence on amplitude and CV is a positive influence on DML and F-min latency. Higher BMI has a negative influence on amplitude and CV.

Diabetes is the main cause of peripheral neuropathy where older patients are at increased risk of diabetic distal symmetrical polyneuropathy (DSPN) due to age-related nerve degeneration and vascular changes. The aim of the study was to investigate the effect of resistance training on nerve conduction, measures of neuropathy and arterial stiffness in older patients with DSPN. In a randomized controlled trial, thirty-four older adults with type-2 diabetes and peripheral neuropathy were enrolled and randomly assigned to experimental and control groups. The experimental group carried out circuit resistance training (1-3 rounds, 11 exercises, 10-15 reps, 50%-60% of 1RM, 3 times per week) for 12 weeks. Measurements were performed at baseline and 48 h after the intervention. Measures of DSPN including Michigan neuropathy screening instrument (MNSI), Michigan diabetic neuropathy score (MDNS), motor nerve action potential amplitude (APA), sensory and motor nerve conduction velocity (NCV) improved following intervention (p < 0.001, p = 0.001, p = 0.034, p = 0.001, and p = 0.001, respectively). Sensory APA did not change after the intervention (p = 0.139). Cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI) improved in the experimental group compared with the control group (p = 0.014 and p = 0.033, respectively). In addition, HbA1C decreased following the 12-week resistance training program (p = 0.002). Older adults with DSPN respond positively to resistance training by improved neuropathy symptoms, nerve conduction, arterial stiffness and glucose regulation. Resistance training offers a positive intervention that can abate the progression of DSPN in older adults.

UNASSIGNED: To investigate the relationship between neurological deficit and subsequent recovery as assessed by ASIA score and findings of electrodiagnostic study in acute spinal cord injury (SCI) patients.
UNASSIGNED: Thirty-five patients with acute SCI presenting within 48 h of injury were clinically evaluated for the level, extent, and severity of SCI according to the ASIA standards in a tertiary-level care center. Electrodiagnostic studies of bilateral two motor (tibial and peroneal), one sensory (sural) nerves, and five muscles [iliopsoas, vastus medialis, tibialis anterior, gastrocnemius, and extensor hallucis longus (EHL)] were conducted and repeated at 3 months and 6 months.
UNASSIGNED: The neurological recovery was highly significant (p < 0.001) at 6 months. The difference in mean amplitude was statistically significant (p < 0.05) for all the nerves; mean conduction velocity significant for peroneal and sural nerves, and with no significant difference in mean latency. The differences in mean recruitment of motor unit potential (MUP) and mean peak-to-peak amplitude were highly significant (p < 0.001). Statistically significant kappa agreement between neurological recovery according to ASIA score and nerve conduction velocity was found for right tibial nerve (K = 0.324); electromyography finding of recruitment of MUP with right and left tibialis anterior (k = 0.400) and left EHL (k = 0.407); peak-to-peak amplitude with right tibialis anterior (k = 0.211), right gastrocnemius (k = 0.390), and right EHL (k = 0.211).
UNASSIGNED: There is a strong relationship between electrodiagnostic findings and ASIA scoring to predict neurological deficit and subsequent recovery after acute traumatic SCI. Serial neurologic evaluation by ASIA score and electrodiagnostic studies may help in designing customized rehabilitation programs for the patients according to the expected neurological recovery; and evaluating future research in the field of SCI with more scientific authenticity.

UNASSIGNED: Association of peripheral neuropathy with diabetic retinopathy is known but the relationship of preclinical neuropathy with various grades of retinopathy is not well documented. This study evaluated the association of preclinical peripheral neuropathy using nerve conduction studies with various grades of retinopathy.
UNASSIGNED: Cases of diabetic retinopathy of various grades but asymptomatic for peripheral neuropathy underwent nerve conduction studies of the lower limbs using Caldwell machine and Sierra wave software. The risk factors for retinopathy and association of neuropathy with various grades of retinopathy were analyzed by bivariate and multivariate regression analysis.
UNASSIGNED: The overall prevalence of neuropathy was 75.6% (sensory 58.54% and combined motor and sensory 17.1%) with increase in prevalence with increase in severity of retinopathy. Duration was positively associated with neuropathy (OR = 1.13, 95% CI = 1.02-1.24; P = 0.012); moderate nonproliferative diabetic retinopathy (NPDR) (OR = 5.60, P = 0.002), severe and very severe NPDR (OR = 5.8, P = 0.041), and PDR (OR = 16.05, P = 0.000) were significantly at higher risk for having neuropathy as compared to mild NPDR.
UNASSIGNED: Duration and severity of retinopathy are important risk factors for peripheral neuropathy. There is a high prevalence of peripheral neuropathy among diabetics with retinopathy especially with severe grades, when neuropathy is diagnosed using nerve conduction studies.

A new technique to obtain the sensory nerve action potential (SNAP) of the medial femoral cutaneous nerve is described.
SNAPs were recorded from 104 subjects with a bar recording electrode 10 cm proximal to the patella along an imaginary line drawn between the medial edge of the patella and the femoral pulse below the inguinal ligament. Stimulation was applied 14 cm proximal to the recording point.
There were 104 healthy subjects. Onset latency of the SNAPs was 2.20 ± 0.16 ms (mean ± SD), peak latency was 2.70 ± 0.16 ms, peak-to-peak amplitude was 7.5 ± 3.0 μV, and conduction velocity was 51.5 ± 3.0 m/s. The side-to-side difference in the mean amplitude was 22.27 ± 13.6%.
This new technique is easy, reliable, and reproducible, and should prove useful for the evaluation of neuropathies of the medial femoral cutaneous nerve.

The combined electroneurography and muscle ultrasound examination (ENG-USM) in adult patients showed a correlation between the compound motor action potential (CMAP) and muscular thicknesses (MT). No similar studies exist regarding the neonatal period.
To evaluate the correlations between the maximum compound muscle action potential (CMAP) and maximum muscle thickness (MT) in term and premature newborns versus a group of young adults, as measured by combined electroneurography-ultrasonography (ENG-USM) to assess the stages.
Observational cohort study.
We studied 36 subjects (14 premature and 11 term infants, and 11 young adults), who underwent ENG-USM of the tibialis anterioris (TA) muscle.
We measured: 1) Onset-Peak (O-P) and Peak-to-Peak (P-P) maximum CMAP; 2) maximum MT; and 3) MT at the detected maximum CMAP.
The maximum CMAP in term newborns studied was about 1/3 of the mean value measured in the adults; the differences between O-P and P-P values of the term versus premature infants were not significant. We did not find a good correlation between maximum MT and maximum CMAP in the term (r = 0.63) newborns, contrary to what was found in preterms (r = 0.95) and in young adults (r = 0.98).
Our ENG-USM study shows that in newborns, the site of innervation of the neuromuscular plaque does not correspond to MT since muscle growth is related to the period of development, and depends on the progression of the nerve terminal branches that go to innervate the same muscle.