Median Nerve Conduction Studies Research Articles

P-NE012. Comparison of orthodromic and antidromic median and ulnar sensory nerve conduction studies in neuropathy

Introduction . Median and ulnar nerves are the most frequent nerves involved in the upper limb neuropathy. Sensory nerve conduction studies (NCS) are often practiced to identify the abnormalities in neuropathy. NCS methods consist of orthodromic and antidromic. The antidromic method produces a greater amplitude, faster conduction, yet with the potential of motor nerves stimulation. On the other hand, the orthodromic method shows smaller amplitude, more difficult to detect neuropathy, but do not stimulate motor nerves. Aim: This study compares the orthodromic and antidromic sensory (NCS) examination of median and ulnar nerve using signals in different directions. Methods . A cross sectional study at RSUP dr. Mohammad Hoesin Palembang in the period of July15, 2019 until September15, 2019 was conducted. There were 64 subjects with median and ulnar nerve neuropathies included in the study after selection through inclusion and exclusion criteria. Each sample had an orthodromic and antidromic sensory (NCS) examination. Data analysis used was the kappa comparative hypothesis test. Results . The results of the statistical analysis showed slight agreement with a value of k = 0.01–0.20 between the two orthodromic and antidromic methods in the latency and amplitude of ulnar nerve and latency of median nerve. The kappa result in amplitude of median nerve showed fair agreement with a value of kappa 0.21–0.40, and substantial agreement in velocity with the value of kappa 0.61–0.80. Meanwhile, in ulnar nerve, the velocity showed moderate agreement with the value of kappa 0.41–0.60. Conclusion . Both sensory (NCS) orthodromic and antidromic methods have a good agreement in velocity, thus both methods can be used and are able to provide interpretations of similar abnormalities in neuropathy examination.

Prolonged median distal sensory nerve action potential duration in carpal tunnel syndrome.

Routine nerve conduction study (NCS) parameters are less sensitive in the early stage of carpal tunnel syndrome (CTS). Recently, some studies have shown that prolonged distal sensory nerve action potential (DSNAP) duration may be a more sensitive technique for the diagnosis of demyelinating peripheral neuropathies. We aimed to evaluate the sensitivity of median DSNAP duration in patients with CTS. DSNAP duration and routine NCS data of the median nerve were retrospectively collected in 173 CTS patients, 73 controls, and 78 cervical radiculopathy patients. Prolonged median DSNAP durations were found in 22 patients (22/35, 63%) and 36 patients (36/54, 67%) in the minimal and mild CTS groups respectively, which was more sensitive than routine NCS parameters. The percentage of patients demonstrating abnormalities in median NCS was significantly increased from 80% to 92% with the addition of DSNAP duration. Our results demonstrate the electrodiagnostic value of median DSNAP duration for the diagnosis of CTS, especially in early cases.

Prevalence of Martin-Gruber Anastomosis in Healthy Subjects: An Electrophysiological Study from Raigarh, Chhattisgarh.

Martin Gruber anastomosis is a common anomaly in forearm between median and ulnar nerve. It may lead to technical pitfall or misinterpretation of nerve conduction studies of these nerves. The aim of this studywasto determine the prevalence of Martin-Gruber Anastomosis (MGA) in healthy Raigarh subjects by electrophysiological evaluation. A cross-sectional study was conducted in both forearms of 140 healthy subjects. Electrophysiological studies were performed to measure compound muscle action potentials of abductor pollicis brevis, abductor digiti minimi and first dorsal interosseous muscles when stimulated from distal (wrist) and proximal (elbow) site. Descriptive and analytic statistics were performed using SPSS software. MGA was found in 44 (15.71%) out of the 280 forearms in 30 (21.4%) out of 140 subjects. It was present in 14 males and 16 females. Most frequent type of MGA was of Type II in both genders. The MGA was found bilaterally in 14 subjects. In unilateral cases 8 subjects had MGA in right forearm and 8 subjects had MGA in left forearm. The high prevalence of MGA in the Raigarh population suggest that the orthopedics and neurosurgeons should also take in account this anatomic anomaly while analyzing median and ulnar nerve conduction studies or needle electromyography.

Report of a trial use of the original chart-type manual for the median nerve conduction study

Report of a trial use of the original chart-type manual for the median nerve conduction study

Temporal evolution of nerve conduction study abnormalities in anti‐myelin‐associated glycoprotein neuropathy

A distal-predominant demyelinating symmetric pattern is most frequent in patients with neuropathy associated with anti-myelin-associated glycoprotein (MAG) antibodies. The literature however lacks longitudinal data to describe whether this is consistent over time. From the Ottawa Neuromuscular Center database, we identified 23 patients with both immunoglobulin M gammopathy and anti-MAG antibodies. For median, ulnar and fibular motor conduction studies, we analyzed distal latency and amplitude, negative peak duration, terminal latency index (TLI), and conduction velocity. For median, ulnar, sural, and superficial fibular sensory conduction studies, we analyzed distal latency and amplitude. Results were compared for the earliest and the latest data sets. The mean time interval between the two assessment points was 6.5 years. Median and ulnar motor nerve conduction studies did not show a significant change for any of the parameters tested. There was disproportionate prolongation of median distal motor latency and reduction in TLI, compared to the ulnar nerve. Deep fibular motor conduction studies showed a marked reduction in amplitudes over time. Sensory potentials were recordable in the upper limb in less than 50% at the first study and less than 25% on the most recent study. There was an even larger attrition of recordable sural and superficial fibular sensory potentials. Our results highlight the stability of median and ulnar motor conduction study results over a mean observation period of 6.5 years. In contrast, lower limb motor and all sensory potentials show a marked trend toward becoming unrecordable.

Median nerve conduction studies in rabbits

BackgroundWhen planning nerve conduction studies using animal models, the sciatic nerve is often used and the upper extremity nerves are not preferred due to the size of laboratory animals. This study aimed to present the method and mean values of median nerve conduction studies in laboratory rabbits. Fifty-five six-month-old male New Zealand white rabbits weighing 2 to 2.5 kg were included in nerve conduction studies performed under anesthesia. The compound muscle action potential amplitude and distal latency values were recorded for the median motor nerve with the electrodes placed on the flexor digitorum superficialis muscle and tendon.ResultsA total of 110 median nerves were evaluated. The mean amplitude of the median nerve was 30.6 ± 6.8, mV the median nerve distal latency was 1.3 ± 0.2 ms, and the mean intensity of stimulation inducing a response was 2.5 ± 1 mA.ConclusionsThe mean values obtained by the median motor nerve conduction method in this study can act as a guide for future nerve interventions undertaken in the upper extremities.

High prevalence of carpal tunnel syndrome in individuals with rare nerve growth factor-beta mutation.

In Sweden, a large family with a point mutation in the nerve growth factor-beta gene has previously been identified. The carriers of this mutation have reduced small-fibre density and selective deficits in deep pain and temperature modalities. The clinical findings in this population are described as hereditary sensory and autonomic neuropathy type V. The purpose of the current study was to investigate the prevalence of carpal tunnel syndrome in hereditary sensory and autonomic neuropathy type V based on clinical examinations and electrophysiological measurements. Furthermore, the cross-sectional area of the median nerve at the carpal tunnel inlet was measured with ultrasonography. Out of 52 known individuals heterozygous for the nerve growth factor-beta mutation in Sweden, 23 participated in the current study (12 males, 11 females; mean age 55 years; range 25–86 years). All participants answered a health questionnaire and underwent clinical examination followed by median nerve conduction study in a case–control design, and measurement of the nerve cross-sectional area with ultrasonography. The diagnosis of carpal tunnel syndrome was made based on consensus criteria using patient history and nerve conduction study. The prevalence of carpal tunnel syndrome in the hereditary sensory and autonomic neuropathy group was 35% or 52% depending on whether those individuals who had classic symptoms of carpal tunnel syndrome but negative nerve conduction studies were included or not. Those who had a high likelihood of carpal tunnel syndrome based on classic/probable patient history with positive nerve conduction study had a significantly larger median nerve cross-sectional area than those who had an unlikely patient history with negative nerve conduction study. The prevalence of carpal tunnel syndrome was 10–25 times higher in individuals heterozygous for the nerve growth factor-beta mutation than the general Swedish population. Further studies are needed to better understand the underlying pathophysiological mechanisms.

Correlations Between Median Nerve Sonography and Conduction Study Results and Functional Scales in Amyotrophic Lateral Sclerosis

We aimed to compare the sonographic measurement of median nerve cross-section area (CSA) in patients with Amyotrophic Lateral Sclerosis (ALS) and healthy individuals. The effect of duration of the disease on correlations between paraclinical findings and ALS functional rating scale (ALSFRS) were secondarily aimed to be evaluated. The cross-sectional study was approved by the Ethical Committee of Iran University of Medical Sciences and conducted between January 2017 and December 2018. We evaluated the median nerve surface area by means of sonography in 35 ALS patients and 35 healthy controls. Compound muscle action potential (CMAP) amplitudes during nerve conduction study and ALSFRS were recorded by the same trained specialist. Data were analyzed using SPSS software version 18. We did not find a significant difference between CSA in ALS patients and the normal population (P>0.05). Comparing to normal individuals, the mean CMAP decreased significantly in ALS patients (6.6±3.07 mV versus 10.25±2.2 mV, P<0.001). ALSFRS correlated with both CSA of the median nerve at the wrist (P:<0.001, r:0.78) and the CMAP (P:<0.001, r:0.74) that were confirmed by regression models designed to consider the effect of disease duration on these correlations. CSA was not different between ALS patients and the normal population, but CMAP decreased in ALS patients. ALSFRS correlated with both CSA and CMAP of the median nerve.

Diagnosis Accuracy of Carpal Tunnel Syndrome in Diabetic Neuropathy.

Background and objectives: Carpal tunnel syndrome (CTS) is a common pathology, but sometimes the diagnosis is delayed in patients with diabetic neuropathy (DN). The aim of the study is twofold: first, to compare the accuracy of ultrasound (US) with that of electroneurography (ENG) in the diagnosis of CTS associated with DN, using the clinical diagnosis as a reference standard, and second, to investigate the correlation between morphological US parameters and electrodiagnosis (EDX) measurements in patients with CTS and DN. Materials and Methods: This study included patients with DN. They were divided into two groups: Control (patients without CTS) and Cases (patients with CTS). We performed US and ENG in both hands, totaling 56 wrists, with 28 wrists in each group. Results: We found that the difference in the sensory distal latencies between the median and the ulnar nerves (ring finger) exhibited the highest diagnostic accuracy of all the US and ENG parameters, areas under the receiver operating characteristic (AUC) = 0.99 (95% CI 0.97–1), and it was significantly different from the best US diagnostic method. The wrist cross-sectional area (CSA) had the most accurate US diagnosis, while the wrist-to-forearm ratio had the worst AUC. Moreover, in the group of CTS and DN patients, the wrist CSA enlargement was statistically directly proportional to the median compound muscle action potential (CMAP) distal latency and inversely proportional to the antidromic median nerve conduction study (NCS) and the orthodromic median palm–wrist NCS. Conclusions: Both examinations can be used with confidence in the diagnosis of CTS overlapping with DN, but the EDX examination seems to be more accurate. Furthermore, we found a positive correlation between the US and EDX parameters.

Systematic prospective electrophysiological studies of the median nerve after simple distal radius fracture

PurposeTo assess whether there is a measurable impairment of median nerve conduction study parameters with uncomplicated distal radius fracture.MethodsPatients were assessed prospectively at the time of cast removal (visit 1) after a standard 6–8 week immobilization for uncomplicated distal radius fracture. Patients with prior entrapment neuropathy or polyneuropathy were excluded. Patients were asked to report sensory symptoms. Median and ulnar motor and sensory conduction studies were performed bilaterally, as well as transcarpal stimulation. All electrophysiologic studies were repeated at a follow-up visit 2, on average 7.8 weeks later.Results39 patients were assessed at visit 1 and 30 (77%) were available for follow-up visit 2. Paresthesia in the median territory on the fractured side were reported in 20% at visit 1 and 26% at visit 2. Electrophysiological evidence of only mild carpal tunnel syndrome was found on the fractured side in 4/39 at visit 1 and 6/30 at visit 2. There were only 2 cases of moderate-marked median neuropathy, both asymptomatic and on the unfractured side. Median motor and sensory latencies and amplitudes did not show statistically significant differences between fractured and unfractured sides with the single exception of median distal motor latency at visit 1.ConclusionsMedian territory paresthesia at the time of cast removal following distal radius fracture are often not associated with electrophysiologic evidence of median neuropathy. Most median nerve electrophysiologic parameters do not significantly differ between the fractured and uninjured sides. Significant traumatic median neuropathy is not likely to be a frequent manifestation of uncomplicated distal radius fracture.Level of evidenceDiagnostic analysis, Level III

Diagnosis and grading of carpal tunnel syndrome with quantitative ultrasound: Is it possible?

The recent diagnostic tools for carpal tunnel syndrome (CTS) include nerve conduction studies (NCS) and ultrasound (US). Quantitative US (QUS) can be used for demonstrating muscle changes according to denervation. The aim of this study was to evaluate if QUS can diagnose and grade the severity of CTS. In this single blinded cross-sectional study, female patients diagnosed with CTS and age-matched healthy female subjects were included in the study. Median and ulnar nerve conduction studies (NCS) were performed for CTS diagnosis. Median and ulnar nerve cross-sectional area (CSA) was measured, and the abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles were longitudinally and transversally visualised. Axial images were analysed for echo intensity (EI) via computer-assisted, grayscale analysis. Intra-rater and inter-rater reliability analysis was performed. The Boston questionnaire was used for the evaluation of symptom severity and functional status. Forty-two patients (42 hands) and 32 controls were included. In the CTS group, 17 patients had mild, 13 patients had moderate, and 12 patients had severe CTS. CSA of the median nerve and APB echo intensity was significantly higher in patients with CTS. However, according to the CTS grade, no significant difference was detected for APB EI. The intraclass correlation coefficient (ICC) was calculated as 0.928 for intra-rater reliability and 0.768 for inter-rater reliability. QUS evaluation is helpful for the diagnosis of CTS, but not for grading. Further studies are needed with a larger population including both genders.

EDITORIAL COMPETENCY BASED MEDICAL EDUCATION CBME A CHALLENGE IN INDIA

Background There are different comparison tests for electrodiagnosis (EDX) of median neuropathy at wrist. When routine tests fail to establish diagnosis especially in mild cases, these tests play crucial role. There are few short segmental and few long segmental median versus ulnar comparison tests.Objectives With current knowledge we aimed to find out whether routine sensory onset latencies difference of median and ulnar nerves can be used as long segmental comparison test for EDX of median neuropathy or not? Effect of gender and body mass index (BMI) on different variables was also assessed.Material and methods Routine median and ulnar sensory nerve conduction study was modified to comparison test by small change in its technique. 50 healthy late teenagers, after careful screening for neurological, musculoskeletal disorders underwent the test.Results Out of 50 participants, 49 actually participants underwent test. Reference values were obtained for modified comparison test. Gender and BMI effect was statistically non significant (p value >0.05) on different test variables. Median Vs Ulnar sensory Onset latency difference was [range: 0-0.6ms, upper limit: 0.3ms, mean (SD): 0.15(0.15)].Conclusion Gender and BMI shows no effect on Routine median Vs Ulnar onset latency comparison test. Reference values are comparable and show no obvious differences with existing comparison tests. Therefore this comparison test may be used for EDX of median neuropathy at wrist in association with other tests.

Different distribution of demyelination in chronic inflammatory demyelinating polyneuropathy subtypes

In demyelinating polyneuropathies, distribution patterns of demyelination reflect underlying pathogenesis. Median and ulnar nerve conduction studies were reviewed in 85 typical chronic inflammatory demyelinating polyneuropathy (CIDP) patients and 29 multifocal acquired demyelinating sensory and motor neuropathy (MADSAM). Distal latencies were prolonged in typical CIDP and near normal in MADSAM. Abnormal amplitude reductions in the nerve trunks were more frequent in MADSAM than typical CIDP. Presumably because the blood-nerve barrier is anatomically deficient at the distal nerve terminals, antibody-mediated demyelination is a major pathophysiology in typical CIDP. In contrast, blood-nerve barrier breakdown is likely to be predominant in MADSAM.

Evaluation of peak or onset latency in the median-versus-ulnar digit four sensory comparison study for diagnosing carpal tunnel syndrome

Aim: Peak or onset latency difference of the median and ulnar nerves can be used in the median-versus-ulnar digit 4 sensory comparison study (MUD4CS) for electrodiagnosis of carpal tunnel syndrome (CTS). This study aimed to investigate the differences in results while using peak or onset latency difference.Material and Methods: The hands of patients with clinical CTS diagnosis but normal median nerve conduction study (NCS) results were included retrospectively in this study. NCSs of the median and ulnar nerves with onset and peak latencies in MUD4CS were recorded. Onset and peak latency differences of the two nerves and also peak-onset latency difference of the median nerve in MUD4CS were calculated. The hands were divided into two groups according to MUD4CS findings: abnormal and normal. The hands in the abnormal group were also divided into peak and onset subgroups.Results: A total of 277 hands were included in this study. Abnormal MUD4CS results were observed in 103 hands; 77 hands based on onset latency difference, and in 76 hands based on peak latency difference. Median sensory conduction velocity was slower and amplitude was smaller in the abnormal group than in the normal group (p=0.003, p=0.027 respectively). Median peak-onset latency difference was significantly greater in the peak subgroup than in the onset subgroup (p=0.0001).Conclusion: It may be more useful to measure both peak and onset latency differences when diagnosing CTS because some cases may be overlooked by using a single latency difference.

OUR EXPERIENCE IN CARPAL TUNNEL SYNDROME THERAPEUTIC EFFECTIVENESS EVALUATION

Objectives: Analyze the literature data on the incidence and manifestation of carpal tunnel syndrome (CTS), as well as the pathogenesis and treatment options. Perform a specially designed, validated test - Pain Detection. Evaluate the objective state of patients with CTS - sensory impairment, compression test. Assess patients’ neurologic and neurophysiologic data before and after the blockade and evaluate its effectiveness. Perform a specially designed, validated test - Patients` Global Impression of Change scale (PGIC) one month after corticosteroid injection (CSI).Methods and Materials: The study includes an analysis of 55 arms of patients of different age with mild and moderate CTS who came for a neurological examination at the Neurology Outpatient Department of the Pauls Stradiņš Clinical University Hospital during the period of 01.08.2018 – 01.01.2019. All patients were analyzed clinically and neurophysiologically before CSI and one month after CSI. A Pain Detect scale, PGIC scale, compression tests and sensory tests were used for the evaluation of clinical symptom. A median nerve sensory and motor nerve conduction study was performed.Results: According to the Pain Detect scale, 60% of patients showed neuropathic pain before CSI, and 78% of patients presented clinical effectiveness after CSI. 98% of patients present clinical effectiveness after CSI in the PGIC scale. 85% of patients had improvement in neurophysiological studies – motor distal latency decreased after CSI. Before CSI, the average motor distal latency was 5.7ms (range 4.5-12.9ms SD±1.5), which was on average 130% from the maximal norm (range 102- 293 SD±36). After the CSI, the average motor distal latency was 5.2ms (range 3.8-10.7ms SD±1.3), which was on average 120% from the maximal norm (range 88-243 SD±30). We didn’t find any significant correlation between the improvement of the patient's clinical condition and the improvement of electrophysiological outcomes.Conclusions: The study concludes that the Pain Detect sensitivity for neuropathic pain evaluation of patients with CTS is 60%. Patients show clinical and neurophysiological improvement after CSI, but there is no correlation between neurophysiological and clinical improvement. The study concludes that the PGIC scale can be used to quickly assess the effectiveness of therapy.

The Effects of Gender and Hand Dominancy on Motor Unit Number Estimation in A Sample of Healthy Iraqis Using Two Different Methods

Background:Motor unit number estimation (MUNE) is a unique electrophysiological technique that was developed to determine a numeric estimate of the number of innervating axons. This technique can be used to determine the approximate number of motor neurons in a muscle or group of muscles. Objective:To test the MUNE values according to subject’s gender and hand dominancy in the normal population. Methods:Healthy volunteers who had neither neuromuscular nor systemic/ metabolic disease, with normal neurological examination were studied. Ninety hands of 56 healthy volunteers (11 males and 45 females) with ages ranging from (24-58) years were included in the study. All had normal median nerve conduction studies. Manual incremental (INC) method and adapted multiple points stimulation (AMPS) method were performed for MUNE. Results:Gender did not have an effect on the scores according to the two studied methods (p=0.054 by INC method and p= 0.700 by AMPS method). Hand dominancy also show no statistically significant difference of the scores of MUNE according to both studied methods (p=0.091) by INC method and (p=0.051) by AMPS method. Conclusion:Incremental stimulation and adapted multiple point stimulation are reliable and easily applicable methods with same reproducibility in estimating motor units with no significant effect for subject gender or hand dominancy. Keywords:Motor unit, motor unit number estimation (MUNE), incremental stimulation (INC) method, adapted multiple point stimulation (AMPS) method Citation:Abdul Muneem SD, Kaddori HG. The effects of gender and hand dominancy on motor unit number estimation in a sample of healthy Iraqis using two different methods. Iraqi JMS. 2019; 17(2): 153-160. doi: 10.22578/IJMS.17.2.9

Interesting effectiveness of ozone injection for carpal tunnel syndrome treatment: a randomized controlled trial.

Purpose: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy in the upper limb. Local injection of different substances has been increasingly used as an acceptable conservative treatment in non-severe cases. This study aimed to evaluate the efficacy and safety of local ozone injection in the management of non-severe CTS.Methods: In the current randomized controlled trial (RCT), 40 patients with mild or moderate CTS were included in two parallel groups. Both of them used the resting volar wrist splint for 8 weeks; while the intervention group received a single dose of local ozone injection, except for the same splinting protocol. The main outcome measures including visual analog scale (VAS) for pain; symptom severity or functional status, based on Boston questionnaire (BQ); and median nerve conduction study, were reassessed 10 weeks after the treatment.Results: All of the measures including VAS, symptom severity, functional status and EDX improved significantly in both groups with the maximal changes in VAS. The VAS reduction was more remarkable in the ozone group than the control group [64% versus 45.3%, respectively]. Moreover, both of the BQ subscales showed significantly higher improvement in the ozone group compared to the control group (P=0.01 and 0.02, respectively). Although the improvement of EDX parameters was slightly better in the ozone group, the difference was not significant. Neither minor nor major side effects were reported.Conclusion: Ozone therapy as a safe and low-cost method, could provide promising results among women with mild to moderate CTS, at least for short-term treatment.Clinical trial registration: IRCT2016040913442N9.

Ultrasonographic and electrophysiologic evaluation of median and ulnar nerves in chronic stroke patients with upper extremity spasticity

Objective: To evaluate the upper extremity nerves of stroke patients morphologically and electrophysiologically and to determine whether there is a relationship between clinical evaluations, ultrasonographic measurements, and electrodiagnostic findings.Methods: This cross-sectional study included 30 chronic stroke patients. After recording demographical data, clinical, ultrasonographic, and electrophysiological evaluations were performed. Clinical evaluations included Brunnstrom Recovery Stages (BRS), Fugl-Meyer Assessment (FMA), Modified Ashworth Scale (MAS), Motricity index (MI), Functional Independence Measurement (FIM), and Functional Ambulation Scale (FAS). For ultrasonographic measurements, median and ulnar nerves were scanned. Median and ulnar nerve conduction studies were performed bilaterally.Results: Mean ages of the patients were 62.2 ± 13.0 years (range 24–84 years; 22 males, 8 females). There was no significant difference in median/ulnar nerve ultrasonographic measurements between paretic and non-paretic sides (p > .05), whereas median nerve motor conduction velocity was significantly slower and median nerve F-wave latency was prolonged on the paretic side (p < .05). The median and ulnar nerve compound motor action potential (CMAP) amplitudes of paretic sides were positively correlated with lower extremity BRS and FAS scores. Median CMAP amplitudes were also positively correlated with FIM scores and ulnar CMAP amplitudes were positively correlated with motricity scores. Moreover, on the paretic side, there were positive correlations of median SNAP amplitudes with FIM and FAS scores (p < .05).Conclusions: Our results showed electrophysiological changes in peripheral nerves on the paretic upper extremities, however, no morphological change was determined. Further studies with larger number of patients and longer follow-up periods are needed to clarify the effect of stroke and spasticity on the peripheral nervous system.

Neuromuscular magnetic stimulation counteracts muscle decline in ALS patients: results of a randomized, double-blind, controlled study

The aim of the study was to verify whether neuromuscular magnetic stimulation (NMMS) improves muscle function in spinal-onset amyotrophic lateral sclerosis (ALS) patients. Twenty-two ALS patients were randomized in two groups to receive, daily for two weeks, NMMS in right or left arm (referred to as real-NMMS, rNMMS), and sham NMMS (sNMMS) in the opposite arm. All the patients underwent a median nerve conduction (compound muscle action potential, CMAP) study and a clinical examination that included a handgrip strength test and an evaluation of upper limb muscle strength by means of the Medical Research Council Muscle Scale (MRC). Muscle biopsy was then performed bilaterally on the flexor carpi radialis muscle to monitor morpho-functional parameters and molecular changes. Patients and physicians who performed examinations were blinded to the side of real intervention. The primary outcome was the change in the muscle strength in upper arms. The secondary outcomes were the change from baseline in the CMAP amplitudes, in the nicotinic ACh currents, in the expression levels of a selected panel of genes involved in muscle growth and atrophy, and in histomorphometric parameters of ALS muscle fibers. The Repeated Measures (RM) ANOVA with a Greenhouse-Geisser correction (sphericity not assumed) showed a significant effect [F(3, 63) = 5.907, p < 0.01] of rNMMS on MRC scale at the flexor carpi radialis muscle, thus demonstrating that the rNMMS significantly improves muscle strength in flexor muscles in the forearm. Secondary outcomes showed that the improvement observed in rNMMS-treated muscles was associated to counteracting muscle atrophy, down-modulating the proteolysis, and increasing the efficacy of nicotinic ACh receptors (AChRs). We did not observe any significant difference in pre- and post-stimulation CMAP amplitudes, evoked by median nerve stimulation. This suggests that the improvement in muscle strength observed in the stimulated arm is unlikely related to reinnervation. The real and sham treatments were well tolerated without evident side effects. Although promising, this is a proof of concept study, without an immediate clinical translation, that requires further clinical validation.

Effects of Anthropometric Measurements on Treatment Outcomes in Patients with Carpal Tunnel Syndrome.

The purpose of this study was to investigate the relationship between anthropometric hand/wrist measurements and outcomes following static wrist splintage in patients with mild-to-moderate carpal tunnel syndrome (CTS). Thirty nine patients with mild-to-moderate CTS were enrolled in this study. Anthropometric measurements of hand and wrist including wrist width, wrist depth, palm length, hand length, wrist ratio (wrist depth/wrist width) and wrist/palm ratio (wrist depth/palm length) were recorded as well as body mass index and ultrasonographic cross sectional area of median nerve. Patients were treated with static wrist splints and evaluated at 2nd, 4th and 12th weeks with Boston Carpal Tunnel Questionnaire, median nerve nerve conduction studies, Visual Analog Scale for pain and Likert Scale for numbness. Following treatment with a static wrist splint, the wrist ratio was correlated significantly with improvements in Boston Functional Status Scale at the second and forth weeks (r = -0.354, p = 0.027 and r = -0.320, p = 0.050 respectively) and Visual Analog Scale at the forth and 12th weeks (r = -0.352, p = 0.030 and r = -0.360, p = 0.029 respectively). Splinting provides symptomatic improvement in mild-to-moderate CTS and this study suggests that the wrist anthropometric measurements may influence treatment outcomes.