Ulnar Motor Nerve Conduction Studies Research Articles

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.

Clinical, Electrodiagnostic Findings and Quality of Life of Dogs and Cats with Brachial Plexus Injury.

Brachial plexus injury (BPI) represents a common consequence of road traffic accidents in humans and small animals. In humans, neuropathic pain is a common symptom after BPI. The aim of the study was to describe the clinical signs, the electrodiagnostic findings, the outcome and the quality of life (QoL) of a cohort of dogs and cats with BPI. Clinical records of 40 dogs and 26 cats with BPI were retrospectively reviewed. Specific attention was put on the evaluation of electrodiagnostic findings (35/40 dogs; 14/26 cats) and telephonic interview results (26/40 dogs; 18/26 cats). The most common neurological condition was the inability to bear weight and sensory deficits on the affected limb. Radial and ulnar motor nerve conduction studies (MNCSs) were absent respectively in 47% (radial) and 62% (ulnar) of dogs and 57% (radial) and 57% (ulnar) of cats. The absence of radial (p = 0.003) and ulnar (p = 0.007) MNCSs in dogs and ulnar MNCSs in cats (p = 0.02) was significantly associated to the amputation of the affected limb. The owners described signs of pain/discomfort in 73% of dogs and 56% of cats. This is the first report suggesting that neuropathic pain/discomfort should be adequately considered in order to improve the QoL.

Evaluation of axonal loss in ulnar sensory nerve fibers recorded from ring and little fingers secondary to idiopathic carpal tunnel syndrome in Egyptian patients

BackgroundThe association between carpal tunnel syndrome (CTS) and ulnar nerve entrapment is unclear, and the extra-median paresthesia in the ulnar nerve territory innervation in CTS is unexplained. Our purpose is to evaluate the neurophysiologic changes in ulnar nerve sensory fibers secondary to idiopathic CTS in comparison to normal subjects, and their relation to the severity of CTS.ResultsThe difference between CTS and control hands regarding all parameters of ulnar motor nerve conduction studies (MNCS) was not statistically significant (p > 0.05). There was a statistically significant difference in all parameters of median sensory conduction study (SCS) and MNCS between CTS and control hands (p < 0.0001) except for conduction velocity and in all parameters of median and ulnar SCS recording digit 4 (D4) (p < 0.05). The mean value of abnormalities of ulnar SCS recording D4 and digit 5 (D5) was significantly higher in moderate and severe CTS hands (p < 0.05). There were significant negative correlations between median motor and sensory latency and ulnar sensory amplitude recording D4 and D5.ConclusionUlnar sensory nerve abnormalities exist among CTS patients, which were more in moderate and severe grades. The drop in amplitude of ulnar nerve sensory response argues in favor of the possible impact of CTS on the ulnar nerve and did not indicate axonal deterioration of the ulnar nerve.

Charcot-Marie-Tooth Disease Type 1A: Influence of Body Mass Index on Nerve Conduction Studies and on the Charcot-Marie-Tooth Examination Score.

Charcot-Marie-Tooth Disease type 1A (CMT1A) is caused by a duplication of the peripheral myelin protein gene 22 at chromosome 17p11.2-12. There is limited data regarding whether body mass index (BMI) affects electrophysiological or clinical data in those with CMT1A. Electrophysiological data, the Charcot-Marie-Tooth examination score (CMTES) and BMI from 101 patients with known CMT1A were obtained and analyzed. When controlling for age, a higher BMI does not affect ulnar motor nerve conduction studies in those with CMT1A, but rather components of the CMTES (loss of pinprick and motor strength in the lower extremities). BMI and clinical components of the CMTES are correlated, but it is uncertain which came first-whether the loss of lower extremity pinprick sensation and motor strength results in a higher BMI or if higher BMI results in these signs.

P259 Object dropping in Carpal Tunnel Syndrome: Clinical and electrophysiological features

Objectives Some patients with Carpal Tunnel Syndrome (CTS) complain of dropping objects. In this study, the clinical and electrophysiological features of CTS patients with (wOD) and without object dropping (w/oOD) were compared. Methods 52 female cases (age range: 21–80) consisting of 20 wOD, 16 CTS w/oOD patients and 16 healthy controls were included. Clinical evaluation included neurological examination, hand preference questionnaire, Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), a questionnaire for frequent object dropping and records of weekly hand usage. Nerve conduction studies (NCSs) were composed of bilateral orthodromic median 2nd finger and ulnar 5th finger sensory NCSs, median-ulnar ring finger sensory latency comparison, and median and ulnar motor NCSs. Median nerve was stimulated at palm, wrist and elbow. Conduction velocity and compound muscle action potential (CMAP) amplitude loss across the wrist was calculated. Results In wOD cases, mean age was older (59 vs. 53 years), symptom duration (42 vs. 29 months) and weekly occupational hand usage times (47 vs. 39 h) were longer, BCTQ symptom severity (2.9 vs. 2.5) and functional status scores (3.1 vs. 2.4) were higher. Sensory and motor NCSs abnormalities were more prominent on the dominant side in wOD, while they were similar on the non-dominant side in both groups. CMAP amplitude loss across the wrist was higher on the dominant side in wOD (27.8% vs. 13.3%). Discussion and conclusion Frequent object dropping may be a sign of severity and chronicity in CTS. Significance The relation between frequent object dropping and clinical and electrophysiological severity of CTS was investigated.

Supramaximal Stimulus Intensity as a Diagnostic Tool in Chronic Demyelinating Neuropathy.

Objective. The ability to correctly identify chronic demyelinating neuropathy can have important therapeutic and prognostic significance. The stimulus intensity value required to obtain a supramaximal compound muscle action potential amplitude is a commonly acquired data point that has not been formally assessed as a diagnostic tool in routine nerve conduction studies to identify chronic neuropathies. We postulated that this value was significantly elevated in chronic demyelinating neuropathy. Methods. We retrospectively reviewed electrophysiology laboratory records to compare the stimulus intensity values recorded during median and ulnar motor nerve conduction studies. The groups studied included normal controls (n = 42) and the following diagnostic categories: chronic inflammatory demyelinating neuropathy (CIDP) (n = 20), acquired inflammatory demyelinating neuropathy (AIDP) (n = 13), Charcot Marie Tooth (CMT) type 1 or 4C (n = 15), carpal tunnel syndrome (CTS) (n = 11), and amyotrophic lateral sclerosis (ALS) (n = 18). Results. Supramaximal intensities were significantly higher in patients with CMT (median nerve: 43.4 mA) and CIDP (median nerve: 38.9 mA), whereas values similar to normal controls (median nerve: 25.3 mA) were obtained in ALS, CTS, and AIDP. Conclusions. Supramaximal stimulus intensity may be used as an additional criterion to identify the pathophysiology of neuropathy. We postulate that endoneurial hypertrophic changes may increase electrical impedance and thus the threshold of excitation at nodes of Ranvier.

A Novel Approach to the Ulnar Motor Nerve Conduction Study with Ultrasound Assistance in Patients with Anterior Ulnar Nerve Transposition Surgery

PM&RVolume 5, Issue 9S p. S160-S160 General Rehabilitation A Novel Approach to the Ulnar Motor Nerve Conduction Study with Ultrasound Assistance in Patients with Anterior Ulnar Nerve Transposition Surgery Hamilton Chen MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this authorXing Zhao MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this authorAmirpasha Ehsan MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this authorRonald Takemoto MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this author Hamilton Chen MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this authorXing Zhao MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this authorAmirpasha Ehsan MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this authorRonald Takemoto MD, UCI Medical Center, Los Angeles, CA, United StatesSearch for more papers by this author First published: 17 September 2013 https://doi.org/10.1016/j.pmrj.2013.08.085Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume5, Issue9SSeptember 2013Pages S160-S160 RelatedInformation

Application of ultrasound to the median sensory and ulnar motor nerve conduction studies

Application of ultrasound to the median sensory and ulnar motor nerve conduction studies

Ulnar Motor Nerve Conduction Study for Lesion Localization in Ulnar Neuropathy at Elbow

Ulnar Motor Nerve Conduction Study for Lesion Localization in Ulnar Neuropathy at Elbow

Application of Ultrasound in an Ulnar Motor Nerve Conduction Study after Anterior Ulnar Nerve Transposition

Ulnar nerve entrapment at the elbow (cubital tunnel syndrome) is one of the most common peripheral nerve entrapments. Surgical management of cubital tunnel syndrome often involves anterior transposition of the ulnar nerve. After surgical treatment of ulnar neuropathy, patients will often be referred for a repeat nerve conduction study (NCS) to assess for changes in conduction velocity. However, in a patient with a transposed ulnar nerve, it is technically difficult to localize the proper NCS stimulation sites, requiring nerve mapping by multiple submaximal stimulations. We present a case report utilizing ultrasound to localize and map the transposed ulnar nerve for the ulnar motor NCS test across the elbow. As a result, the need for nerve mapping through repeated stimulation is eliminated.

The Second Lumbrical–Interosseous Latency Comparison in Carpal Tunnel Syndrome

Carpal tunnel syndrome (CTS) is the most common nerve entrapment syndrome. Electromyogram (EMG) is beneficial in supporting the diagnosis of CTS. We compared standard nerve conduction studies of EMG with median and ulnar motor nerve conduction studies from recordings of second lumbrical and interosseal muscles in supporting the diagnosis of CTS. In this study, a total of 242 patients were included, and a total of 375 hands were involved. Electrophysiologic CTSs were diagnosed in 283 hands of 161 patients. A significant association between second lumbrical-interosseal distal motor latency difference (2LI-MDLD) and CTS was found in this study. Statistically, every 0.1 increment in the 2LI-MDLD value was observed to increase the risk of disease by 1.74. When a cut-off of ≥ 0.5 for 2LI-MDLD is taken for predicting CTS, the sensitivity of the test is found to be 89.4% and specificity 84.4%. When the cut-off value for motor distal latency of second lumbrical of the median nerve (2L-MDL) was taken as ≥ 3.15 milliseconds in the diagnosis of CTS, the sensitivity of the test was 87.3%, and specificity 70.7%. Previous reports and our findings suggest that in CTS diagnosis, not only 2LI-MDLD value but also 2L-MDL value are easy and rapidly obtainable and offer additional information in very severe cases where compound muscle action potentials (CMAP) cannot be recorded from the abductor pollicis brevis (APB) muscle.

Assessing Weakness in Patients with Ulnar Neuropathy

The aim of this study was to compare the use of a custom intrinsic hand dynamometer (HD) with that of a standard pinch dynamometer (PD) in assessing strength in patients with ulnar neuropathy at the elbow. Nine patients (age, 53 ± 3 yrs) with clinical and electrophysiological features of ulnar neuropathy at the elbow with conduction block (CB) were studied. All underwent bilateral ulnar motor nerve conduction studies recording from the first dorsal interosseous and a quantitative measurement of strength of the first dorsal interosseous using a custom-made HD and a standard PD. The maximal strength of the ulnar neuropathy at the elbow-affected side (16.2 ± 8.0 N) was found to be significantly lower than that of the unaffected side (27.9 ± 11.2 N), as measured by HD. Strength differences were not significant between the affected (62.7 ± 26.4 N) and unaffected sides (48.0 ± 20.5 N) using PD. HD force decrement (in comparison with the unaffected limb) correlated strongly with CB percentage (r = 0.74). No relationship was found between PD and CB (r = 0.05). HD was better able to measure the weakness of affected muscles than did PD, and its results correlated well with the extent of electrophysiological CB. Therefore, a custom HD would provide a better indication of disease severity, progression, or improvement in strength in studies of ulnar neuropathy at the elbow with CB.

Effect of Demyelinating Ulnar Nerve Injury on Strength and Fatigue

Conduction block (CB) from focal neuropathy is often associated with weakness and fatigue in affected muscles. Ulnar neuropathy at the elbow (UNE) provides an excellent model to examine the relationships between electrophysiologically defined CB and quantitative measurement of weakness and fatigue. Eight healthy control subjects (47 ± 14 years) and nine patients (53 ± 3 years) with clinical and electrophysiological features of UNE with CB were studied. All underwent bilateral, ulnar motor nerve conduction studies recording from the first dorsal interosseous muscle as well as quantitative measurement of strength and fatigue of the first dorsal interosseous with a custom dynamometer. Strength and fatigue were similar in the dominant and nondominant hands of control subjects and unaffected limb in patients. Varying degrees of conduction block (14-62%, mean 36%) and conduction slowing (31 m/s ± 7) were observed in those with UNE. CB was associated with significant reductions in strength (42%) and fatigue (23%) on a timed fatigue task. The reductions in strength (r = 0.74) and fatigue (r = 0.60) were strongly correlated with the degree of CB. CB in UNE defined by electrophysiological criteria was strongly correlated with weakness and fatigue in the first dorsal interosseous. Fatigue may be simply related to the reduction in strength, but activity or frequency dependent CB may also contribute.

The effect of wrist position on the conduction velocity of the ulnar nerve

Objective: The purpose of this study was to investigate the effect of wrist position on the ulnar nerve conduction velocity. Method: Ulnar motor nerve conduction studies were performed bilaterally in twenty healthy adult volunteers. For each limb, nerve conduction study was carried out in two different positions. In the first position, shoulder were abducted, elbow and wrist flexed to 90. For the second position, all joints were kept constant except for the wrist where it was extended. Routine conduction study was performed in both wrist positions. All data were statistically analyzed. Results: The average conduction velocities in the wrist flexed position were 61.6 m/sec for the forearm segment and 62.3 m/sec across elbow. With the wrist extended, the average was 62.6 m/sec and 64.1 m/sec, respectively. The differences in conduction velocities between two different wrist positions were statistically significant (p＜0.05). In the wrist flexed position, the average measured latencies were 2.3 msec with wrist, 5.4 msec below elbow, and 7.4 msec above elbow stimulation, compared to wrist extended which showed 2.4, 5.4 and 7.2 msec, respectively. The difference of latencies at wrist between the two wrist positions was statistically significant (p＜0.05). Conclusion: The authors conclude that wrist position affect ulnar nerve conduction velocity.