Median-ulnar Sensory Latency Difference Research Articles

Clinical Evaluation and Diagnostic Utilities of Different Nerve Conduction Tests in 100 Patients with Carpal Tunnel Syndrome.

Background and Purpose:The purpose of the study is to determine whether the clinical profile of patients with carpal tunnel syndrome (CTS) has been same over the years with the help of routine and comparative electrodiagnostic tests.Methods:A prospective study of 100 patients with suspected CTS was conducted without controls. Three provocative maneuvers were performed. Routine and comparison nerve conduction tests were performed, i.e., second lumbrical interossei motor latency difference (2 LIMLD), digit 4 median-ulnar sensory latency difference (D4MUSLD), palm wrist distal sensory latency difference (PWDSLD), and digit 1 median-radial sensory latency difference (D1MRSLD). Data entry, analysis, and statistical evaluation were done using International Business Machines Corporation Statistical Package for the Social Sciences statistics package (IBM, SPSS).Results:A total of 195 hands of 100 patients met the criteria for CTS. Forty-three percentage of patients were homemakers. Considering the rapidly changing communication technology, we observed 84% patients had aggravation of symptoms with continuous long-term daily mobile phone use (>30 min per session per day). We noted positive Tinel's sign in only 25%. Phalen's sign was positive in 53 right hands with mean duration of 11.49s (standard deviation [SD] ± 2.54 s) and was positive in 26 left hands with mean being 10.4 s (SD ± 1.91 s). The mean motor distal latency of median was 4.67 ms (SD ± 1.71 ms) and mean sensory distal latency of median was 3.24 ms (SD ± 1 ms). On internal comparison testing, mean difference in 2 LIMLD was 0.7 ± 0.3 ms, in D4MUSLD was 0.81 ± 0.32, in PWDSLD was 0.71 ± 0.20, and in D1MRSLD was 0.76 ± 0.32.Conclusion:Further analysis of clinical profile needs to be done, and new risk or provoking factors should be analyzed in patients with CTS.

Karpal tünel sendromunda dördüncü parmak median- ulnar duysal yanıt latans farkı testinin kullanımı

Objective: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. In this study, 4th finger median and ulnar nerve sensory latency difference test in minimal and mild carpal tunnel syndrome and the amplitude difference test between the 2nd finger median sensory response and the 5th finger ulnar sensory response were evaluated and their usefulness were discussed. Material and Method: In this study, the patients admitted to Sisli Etfal Training and Research Hospital Neurology Clinic, EMG laboratory with the diagnosis of CTS were included. In addition to conventional electrophysiological methods, 4th finger median - ulnar nerve sensory latency difference test was used. Electrophysiological studies were performed using Medelec Saphire 4E EMG device. Data was evaluated with Statistical Package for Social Sciences (SPSS) for Windows 17 program and descriptive analysis was performed. Results: In 3 (17.64%) of the 17 patients who had abnormality in the 4th finger of median-ulnar sensory latency difference test, 2nd digit median nerve sensory response amplitude was found to be lower than the 5th digit ulnar nerve sensory amplitude response. Conclusion: In our study, which is a preliminary study, a small number of patients whose 4th finger median-ulnar sensory latency difference test were abnormal also revealed a relative decrease in 2nd digit median nerve sensory response amplitude. Further studies with a larger group of patients are needed. The amplitude difference test between 2nd digit median and 5th digit ulnar sensory response may be an alternative sensitive method in order to obtain faster results and to identify early cases of CTS.

Do Comorbid Ulnar Symptoms or Ulnar Neuropathy Affect the Prognosis of Workers With Carpal Tunnel Syndrome?

To the Editor, Carpal Tunnel Syndrome (CTS) is a common and costly disease among working-aged adults, and a leading cause of work-related disability, 1 affected almost 5 million U.S. workers, with prevalence estimated between 3.1% and 7.8%.2 While prognosis following surgery has been described,3,4 many questions exist about predictors of CTS prognosis in working populations.5 The presence of ulnar symptoms or neuropathy have been considered predictive of a poor outcome in CTS cases. We aimed to describe three-year evolution of CTS with and without ulnar symptoms in a large cohort of worker. This study presents data collected prospectively on 1107 newly hired workers in the US, recruited from participating companies recruited from eight employers and three trade unions, representing manufacturing, construction, biotechnology, and healthcare, between July 2004 and October 20066 and followed for three years (n=888). Subjects came from three main occupational groups: construction apprentices, office and laboratory workers and service workers/housekeepers.6 At baseline, subjects answered questions about the presence of hand pain in the past year (occurring 3 times or lasting at least one week), and the nature and location of symptoms. Bilateral nerve conduction studies were performed for median and ulnar nerves at the wrist using the NC-Stat automated nerve conduction testing device (NEUROMetrix, Inc., Waltham, MA). The NC-Stat device followed an automated testing protocol to measure median and ulnar distal motor latencies (wrist-thenar eminence and wrist-hypothenar eminence) and distal sensory latencies (wrist-third finger and wrist-fifth finger.7 Abnormal median nerve conduction was defined as sensory latency >3.5 ms (14 cm) OR motor latency >4.5 ms OR median-ulnar sensory latency difference (MUDS) of > 0.5 ms (14 cm). For ulnar nerve, we used sensory OR motor latency above the 95th percentile. Subjects were categorized according to baseline data into mutually exclusive groups (see table 1). Workers with symptoms of CTS with and without fifth finger involvement were also described, including those with confirmed CTS and confirmed ulnar syndrome (symptoms AND abnormal nerve studies)4. Table 1 Description of outcomes at follow up (severe Hand pain, functional status limitation on Levine scale and job limitation) among subjetcts categoreized at baseline on clinical status and nerve conduction status. Three outcomes were used at follow-up: “severe hand pain”, defined as hand pain within the past 30 days with a rating of 5 or higher on a scale of 0 (no discomfort) to10 (worst discomfort imaginable); “functional status limitations” assessed via the Levine Functional Status Scale; and “job limitation”, a dichotomous composite outcome that included all workers who reported a limitation attributed to hand symptoms in one or more of the following areas: 1) limited ability to work, 2) decreased productivity, 3) lost time from work, 4) placed on job restrictions, and a 5) change in job or employer. Among the 888 workers followed, baseline mean age was 30.3 years (range 18-66 years,) and 63.9% were men.. CTS prevalence and incidence was similar to that reported in other worker populations.11–13 From table 1, ulnar neuropathy at the wrist was associated with CTS in only 4 of the 21 CTS cases at follow-up. These workers had a slightly higher proportion of severe hand pain but similar limitations. Over half of the subjects with symptoms of CTS had symptoms in the fifth finger (n=45/79), without differences on the other outcomes, and only one worker had a confirmed CTS and ulnar syndrome. Our study was limited by the small number of cases, and by use of the NC-Stat automated nerve testing device7, which limited our testing of ulnar neuropathy to the wrist. Nonetheless, our findings provide an interesting perspective. In clinical settings, some case reports suggest that associated median and ulnar neuropathies affect prognosis after nerve release.3,8–10 However, our results are consistent with a recent study of ulnar neuropathy at the elbow; while 60.5% of subjects had persistent symptoms at follow-up, there were no differences in disability and symptom severity seen among the 5% of patients with ulnar neuropathy who had comorbid CTS.14 Ulnar neuropathy is relatively understudied, and future research is needed from large prospective studies to determine the prognosis, management, and prevention of ulnar neuropathies from entrapment at the wrist or elbow.

Simple clinical tests in severe carpal tunnel syndrome.

Patients with severe carpal tunnel syndrome may be characterised by an atypical clinical picture. They assess complaints as becoming less bothersome than in the past. It seems that this may influence the diagnostic value of some clinical tests used in physical examinations. The aim of the study was the selection of the most reliable clinical tests in a group of patients with severe carpal tunnel syndrome. The material comprised 38 cases of severe form of the disease in a group of 37 prospective patients. The methods consisted in the evaluation of the rate of positive results of selected clinical tests, and in the comparison of their statistical correlation with selected parameters of median nerve conduction. The study results indicated that high incidence of two-point discrimination disorders showed a correlation with the sensory conduction parameters, including the median-ulnar sensory latency difference. The Durkan's and Phalen's tests were positive in almost all patients with advanced carpal tunnel. The Katz hand diagram revealed significantly enhanced sensitivity in the "probable" pattern. We speculate that the two-point discrimination, evaluated with the use of a simple paper clip, enables the selection of a group of patients with severe form of the syndrome for further differentiation. The tool used for facilitating the differential diagnosis is the Katz hand diagram. The Durkan's and Phalen's tests have an equally high value. However, they show no correlation with the conduction parameters, as measured by EMG.

The relationship of pre- and postoperative median and ulnar nerve conduction measures to a self-administered questionnaire in carpal tunnel syndrome

Following carpal tunnel release (CTR), only very modest correlations have been found between subjective symptoms and function indexes compared to neurophysiological measures. The objective of this study was to evaluate this relationship by comparing the self-administered Boston symptom severity score and function severity score questionnaire against nerve conduction studies (NCS) before and after CTR using two different electrophysiological techniques. Carpal tunnel release was performed in 51 patients (62 hands). Pre- and postoperative NCS were evaluated using both conventional neurophysiological methods and by means of a new hand-held device. Preoperatively there was almost no correlation between symptom severity and function scores and NCS results. Following surgery however, both symptom severity and function showed a modest, but significant improvement in their correlation to NCS (at highest r=0.405, P<0.01). This improvement in the relation of subjective measures to neurophysiological results was seen in both median nerve sensory and motor conduction as well as in ulnar nerve motor conduction. In addition to median-nerve dysfunction, it might be suggested that ulnar nerve changes can contribute to symptoms of carpal tunnel syndrome in patients. Several associations were found using a median-ulnar sensory latency difference in the finger-wrist segment and a sensory conduction difference in the palm to wrist segment. Significant correlations were established by both conventional NCS and the new hand-held device.

How to Make Electrodiagnosis of Carpal Tunnel Syndrome With Normal Distal Conductions?

The purpose of this study is to investigate which electrodiagnostic techniques are better in clinically diagnosed patients with carpal tunnel syndrome (CTS) and patients with CTS with normal distal conduction study. A total of 230 clinically diagnosed patients with CTS and 100 normal control subjects were enrolled. All subjects were evaluated by eight electrodiagnostic techniques, including conventional conduction studies: median distal sensory latency and distal motor latency; short distance conduction studies across wrist, including wrist-palm sensory conduction time and wrist-palm motor conduction velocity; comparison of median sensory conduction across the wrist with radial or ulnar nerves in the same limb (median-radial sensory latency difference [M-R] or median-ulnar sensory latency difference [M-U]); and comparison of median wrist-palm and palm-index conduction, including distoproximal conduction time difference and distoproximal conduction time ratio. Normal limits were derived by calculating the mean ± 2 standard deviations from the data of the controls. The sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristic curve with 95% confidence interval of each test were calculated. In clinically diagnosed patients with CTS, M-R is the best diagnostic technique with significant difference in area under the receiver operating characteristic curve (0.912) compared with other tests except that of M-U. The sensitivity, specificity, positive predictive value, and negative predictive value of M-R were 84.3%, 98%, 99%, and 73.1%, respectively. Further evaluation of patients with CTS with normal distal latencies also revealed the best diagnostic value of M-R and M-U with significance to other tests in area under the receiver operating characteristic curve. In clinical practice, after conventional median distal sensory latency and distal motor latency studies, the authors suggest performing M-R or M-U studies instead of segmental conduction or comparative studies of median nerves in the patients with CTS with normal distal latencies.

Comparaison de l’échographie et de l’électroneurographie pour le diagnostic du syndrome du canal carpien en pratique courante

Introduction Many studies had been performed in the last years to prove the usefulness of ultrasonographic measurements of the median nerve in the diagnosis of carpal tunnel syndrome (CTS). We wanted to determine its reliability and to compare this technology with electromyography (EMG) in ordinary diagnostic conditions. Methods The study involved 90 wrists with suspected CTS, 35 controlateral wrists and 52 control wrists. The diagnosis of CTS was confirmed in 81 cases by the hand symptom diagram and the Tinnel and Phalen sign. The EMG examination evaluated medianulnar sensory latency difference to the ring finger and wrist-to-palm sensory conduction velocity. For the ultrasound diagnosis, the cross sectional area of the median nerve at the level of the pisiform bone, was considered. The sensitivity and specificity of the two techniques was calculated. Results Sensitive electroneurographic parameters showed a sensibility and specificity respectively of 79 and 80%. The cut-off point for ultrasound sensibility and specificity using ROC analysis was 11 mm 2 for mean cross-sectional area. Sensitivity and specificity found in this way were 72% and 56%. Reliability was good with intra- and inter-reader intraclass correlation coefficients of 0.99, and interobserver coefficient of 0.88. Sonography found seven CTS among the 17 clinical CTS with normal electrophysiological findings. A statistically correlation was found between the cross-sectional section and the sensitive electrophysiologic parameters ( r = 0.43, p < 0.001). Conclusions In our study, ultrasonographic diagnostic value are not as good as electrophysiological value, like found in recent literature, probably because of the composition of our group of patients which is including many causes of acroparesthesias. This can mean that in clinical practice, sonography is a complementary tool instead, for example in cases of equivocal EMG.

Magnetic resonance imaging compared with electrodiagnostic studies in patients with suspected carpal tunnel syndrome: predicting symptoms, function, and surgical benefit at 1 year

The goal in this study of patients with clinical carpal tunnel syndrome (CTS) was to compare the usefulness of magnetic resonance (MR) imaging with that of electrodiagnostic studies (EDSs) for the following purposes: 1) prediction of 1-year outcomes and 2) identification of patients who are likely to benefit from surgical treatment. The authors prospectively enrolled 120 patients with clinically suspected CTS. The participants were tested using standardized EDSs, MR imaging, and a battery of questionnaires, including the Carpal Tunnel Syndrome Assessment Questionnaire, a well-validated 5-point score of symptoms and function. The EDSs and MR images were each interpreted independently. Patients were reevaluated after 1 year. The decision to treat patients conservatively or by carpal tunnel release was made by the individual surgeon, who had access to the initial EDS but not MR imaging results. Univariate and multivariate analyses were used to determine associations between 1-year outcomes and baseline diagnostic tests. The authors recontacted 105 of 120 participants at 12 months. Of these, 30 patients had had surgery and 75 had not. Patients who had undergone surgery showed greater improvement at 1 year than those who had not had surgery. The length of the abnormal T2-weighted nerve signal on MR imaging and median-ulnar sensory latency difference were the strongest predictors of surgical benefit. There was a clear patient preference for the MR imaging over EDSs. The findings obtained with MR imaging of the carpal tunnel predict surgical benefit independently of nerve conduction studies.

Exclusive electrophysiological motor involvement in carpal tunnel syndrome

Objective: To define the frequency of exclusive electrophysiological motor involvement in carpal tunnel syndrome (CTS).Methods: We reviewed the electrophysiological studies of 2727 consecutive hands with typical symptoms and signs of CTS and at least one abnormal test of the following: median distal motor latency (DML), digit two sensory conduction velocity (D2-SCV), segmental D2-SCV from wrist to palm, median-ulnar sensory latency difference from ring finger stimulation.Results: Thirty-one hands (1.2%) had prolonged median DML (>4.4 ms) with normal SCV (>48 m/s). In 17 of 31 hands, segmental D2-SCV from wrist to palm or median-ulnar latency difference from ring finger stimulation were also performed with normal results in 8 hands, demonstrating a true exclusive electrophysiological motor involvement.Conclusions: In CTS, exclusive electrophysiological involvement of median motor fibers is rare. It may be related to preferential compression of the intraneural motor fascicles clumped superficially in the most volar-radial nerve quadrant or, more probably, to the fact that the recurrent thenar branch may exit the carpal tunnel through a separate ligamentous tunnel within the transverse carpal ligament where it may be preferentially or selectively compressed.