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Ulnar Nerve (ulnar + nerve)
Selected AbstractsUlnar neuropathy at the elbow due to unusual sleep positionEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2000J. Finsterer Abnormal strain of the ulnar nerve over the sulcus due to an unusual sleep position is a rare cause of ulnar neuropathy at the elbow. A 57-year-old patient with Mandelung's deformity developed progressive weakness in the flexion of fingers 4 and 5 and in finger straddling on the left side. Additionally, there was slight wasting of the left hypothenar and the left interossei muscles. Motor and sensory nerve conduction studies of the left ulnar nerve showed delayed conduction velocities over the left ulnar sulcus. He preferred to sleep in a left lateral position with his head lying on a headrest roll, his left forearm being flexed at 110° and his hand lying either under his cheek or placed on the roll. Only three weeks after the patient had been advised to change his sleep position and to sleep without the headrest roll, weakness markedly improved. This case shows that sleeping in a lateral position with the head on a headrest roll and the hand placed on the roll or under the cheek may cause ulnar neuropathy at the elbow. Change of such a habitual sleep position promptly resolves the symptoms. [source] Rapid functional plasticity in the primary somatomotor cortex and perceptual changes after nerve blockEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2004Thomas Weiss Abstract The mature human primary somatosensory cortex displays a striking plastic capacity to reorganize itself in response to changes in sensory input. Following the elimination of afferent return, produced by either amputation, deafferentation by dorsal rhizotomy, or nerve block, there is a well-known but little-understood ,invasion' of the deafferented region of the brain by the cortical representation zones of still-intact portions of the brain adjacent to it. We report here that within an hour of abolishing sensation from the radial and medial three-quarters of the hand by pharmacological blockade of the radial and median nerves, magnetic source imaging showed that the cortical representation of the little finger and the skin beneath the lower lip, whose intact cortical representation zones are adjacent to the deafferented region, had moved closer together, presumably because of their expansion across the deafferented area. A paired-pulse transcranial magnetic stimulation procedure revealed a motor cortex disinhibition for two muscles supplied by the unaffected ulnar nerve. In addition, two notable perceptual changes were observed: increased two-point discrimination ability near the lip and mislocalization of touch of the intact ulnar portion of the fourth finger to the neighbouring third finger whose nerve supply was blocked. We suggest that disinhibition within the somatosensory system as a functional correlate for the known enlargement of cortical representation zones might account for not only the ,invasion' phenomenon, but also for the observed behavioural correlates of the nerve block. [source] Single stimulation of the posterior cord is superior to dual nerve stimulation in a coracoid blockACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 2 2010J. RODRÍGUEZ Background: Both multiple injection and single posterior cord injection techniques are associated with extensive anesthesia of the upper limb after an infraclavicular coracoid block (ICB). The main objective of this study was to directly compare the efficacy of both techniques in terms of the rates of completely anesthetizing cutaneous nerves below the elbow. Methods: Seventy patients undergoing surgery at or below the elbow were randomly assigned to receive an ICB after the elicitation of either a single radial nerve-type response (Radial group) or of two different main nerve-type responses of the upper limb, except for the radial nerve (Dual group). Forty milliliters of 1.5% mepivacaine was given in a single or a dual dose, according to group assignment. The sensory block was assessed in each of the cutaneous nerves at 10, 20 and 30 min. Block performance times and the rates of complete anesthesia below the elbow were also noted. Results: Higher rates of sensory block of the radial nerve were found in the Radial group at 10, 20 and 30 min (P<0.05). The rates of sensory block of the ulnar nerve at 30 min were 97% and 75% in the Radial and in the Dual groups, respectively (P<0.05). The rate of complete anesthesia below the elbow was also higher in the Radial group at 30 min (P<0.05). Conclusions: Injection of a local anesthetic after a single stimulation of the radial nerve fibers produced more extensive anesthesia than using a dual stimulation technique under the conditions of our study. [source] Perineural meperidine blocks nerve conduction in a dose-related manner: a randomized double-blind studyACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 6 2009E. ÖZTÜRK Background: Meperidine has been shown to exhibit a sensory block in peripheral nerves. However, its motor blockade ability is controversial. The aim of this study was to investigate, electroneurographically, the ability of meperidine to inhibit conduction in both sensory and motor fibres in the ulnar nerve. Materials and methods: The study was conducted in a double-blind, placebo-controlled fashion. Eighteen healthy volunteers were randomized into three groups (Saline, meperidine 1% and meperidine 2%). Three millilitre of the study solution was administered to the ulnar nerve perineurally at the level of the wrist by the guidance of a nerve stimulator. Sensory nerve action potential (SNAP) and compound motor action potential (CMAP) amplitudes were recorded. At least a 20% decrease in the initial response amplitude was accepted as a block. Results: The number of individuals with sensory and motor block with saline, meperidine 1% and meperidine 2% were 0/6, 6/6, 6/6 and 0/6, 5/6, 6/6, respectively (P<0.05). The maximum decrease in the median SNAP and CMAP amplitude values were 4.7% and 8.3% with saline; 38.5% and 46.4% with meperidine 1%; and 100% and 97.8% with meperidine 2%, respectively (P<0.05). Median values for the duration of sensory and motor block with meperidine 1% and meperidine 2% were 45, 52.5 and 30, 32.5 min, respectively. Conclusion: Meperidine blocks sensory and motor nerve conduction in a dose-related manner. [source] Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 76JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003D Pareyson The X-linked form of Charcot-Marie-Tooth disease (CMTX) is associated with mutations in the Connexin 32 gene (Cx32) and is the second most common CMT subtype after CMT1A, in which the 17p11.2 duplication is the underlying molecular defect. CMTX is characterized by no male-to-male transmission, intermediate motor conduction velocities (MCV), and more severe disease in males. In our series of CMT patients, we found 9 different Cx32 mutations in 11 families. Overall there were 26 patients, 13 males and 13 females, aged 11,76 yrs. Age at onset ranged considerably (1,60 yrs), but symptoms began earlier in males (mean 15.4 yrs, 77% within age 20) than in females (mean 25 yrs). All patients were autonomous, but disease severity was greater in males, while 4 female carriers were asymptomatic. Pain and tremor were frequent complaints. Two patients had Babinski sign and one had rest tremor. Nerve conduction studies were performed in 23 patients (13 males, 10 females). Upper limb motor conduction velocities (MCV) ranged between 25 and 57 m/s, and were slower in males (25,48 m/s) than in females (34,57 m/s). MCV were in the upper range of CMT1 (25,38 m/s) in 10/13 males but only in 3/10 females. In some cases, nerve conduction slowing was non-uniform within single nerves, and one female patient had a previous diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy. There was considerable asymmetry of involvement between different nerves. The median nerve was often more severely affected than the ulnar nerve, and not only in females, as previously reported, but also in males. Therefore, it appears unlikely that this asymmetry is accounted for by a Lyonization phenomenon. Subclinical abnormalities of central nervous system as revealed by multimodal evoked potential studies were found in 8/10 patients. Expression of Cx32 in the brain is the likely explanation of this finding that confirms previous non-systematic observations. We found seven missense and two nonsense mutations (one novel mutation). Two families presented distinct mutations at the same codon (Arg164), while the Arg22Stop and Arg220Stop mutations were each found in two unrelated cases. Partially supported by a grant from the Italian Ministry of Health to F.T and D.P. (Progetto Ricerca Finalizzata ICS 030.3/RF00.174). [source] Ultrasonography in patients with ulnar neuropathy at the elbow: Comparison of cross-sectional area and swelling ratio with electrophysiological severityMUSCLE AND NERVE, Issue 5 2010Ayse Oytun Bayrak MD Abstract The aim of this study was to determine the diagnostic value of ultrasonographic measurements in ulnar neuropathy at the elbow (UNE) and to assess the relationship between the measurements and the electrophysiological severity. The largest anteroposterior diameter (LAPD) and cross-sectional area (CSA) measurements of the ulnar nerve were noted at multiple levels along the arm, and the distal-to-proximal ratios were calculated. Almost all of the measurements and swelling ratios between patients and controls showed statistically significant differences. The largest CSA, distal/largest CSA ratio, CSA at the epicondyle, and proximal LAPD had larger areas under the curve than other measurements. The sensitivity and specificity in diagnosing UNE were 95% and 71% for the largest CSA, 83% and 85% for the distal/largest CSA ratio, 83% and 81% for the CSA at the epicondyle, and 93% and 43% for the proximal LAPD, respectively. There was a statistically significant correlation between the electrophysiological severity scale score (ESSS) and the largest CSA, the CSA at the epicondyle and 2 cm proximal to the epicondyle, and the LAPD at the level of the epicondyle (P < 0.05). None of the swelling ratios showed a significant correlation with the ESSS. The largest CSA measurement is the most valuable ultrasonographic measurement both for diagnosis and determining the severity of UNE. Muscle Nerve, 2010 [source] A comparison of coracoid and axillary approaches to the brachial plexusACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2000Z. J. Koscielniak-Nielsen Background: Brachial plexus block by the coracoid approach does not require arm abduction and may be more effective than the axillary approach because of a more proximal injection of local anaesthetic. However, the clinical usefulness of the coracoid approach has not been tested in prospective controlled trials. The present randomized, observer-blinded study compared success rates, time to obtain a complete block, frequency of adverse effects and block discomfort in two groups of 30 patients, anaesthetized for hand surgery using either the coracoid or the axillary approach to the brachial plexus. Methods: After subcutaneous infiltration with 5 ml of 1% mepivacaine/adrenaline the brachial plexus was located using a nerve stimulator and an insulated pencil-point needle. Ropivacaine 0.75%, 20,40 ml, depending on body weight, was used for the initial block. In the coracoid (C) group two plexus cords, and in the axillary (A) group four terminal nerves were electrolocated and the volume of ropivacaine was divided equally between them. Spread of analgesia to the arm was assessed every 5 min, by an anaesthetist unaware of the block technique. The block was defined as effective (complete) when analgesia was present in all five sensory nerve areas distal to the elbow. Incomplete blocks were supplemented 30 min after the initial block. Results: In the C group a median 11 min was required for block performance as compared to 12 min in the A group (NS). Onset of block was shorter and the frequency of incomplete blocks lower in the A group (median 17 min and 17%) than in the C group (30 min and 47%, respectively). Lack of analgesia of the ulnar nerve was the main cause of incomplete initial blocks in the C group. All incomplete blocks were successfully supplemented. However, total time to obtain complete block was shorter in the A group than in the C group (29 min vs. 41 min, P<0.05). Accidental arterial puncture occurred in seven patients (five in C and two in A group), which resulted in two haematomas, both in the C group (NS). No permanent sequelae were observed. Conclusion: The axillary approach to the brachial plexus using four injections of ropivacaine results in a faster onset of block and a better spread of analgesia than the coracoid approach using two injections. [source] Safety of anthrax vaccine: an expanded review and evaluation of adverse events reported to the Vaccine Adverse Event Reporting System (VAERS),,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 12 2004John L. Sever Abstract Purpose To assess the safety of a licensed anthrax vaccine (AVA) given to more than 500,000 US military personnel, through review and medical evaluation of adverse events (AEs) reported to the Vaccine Adverse Event Reporting System (VAERS). Methods AEs were summarized by person, vaccine lot, type, frequency and impact. A Delphic approach was used to tentatively assess causality in an effort to detect serious AEs (SAEs) or other medically important AEs (OMIAEs) possibly attributable to AVA. Results The Anthrax Vaccine Expert Committee (AVEC) reviewed 1841 reports describing 3991 AEs (9.4 reports/10,000 doses of AVA) that were submitted to VAERS from 1Q1998 through 4Q2001. One hundred forty-seven reports described an SAE or OMIAE, of which 26 were tentatively rated as possible, probable or certain consequences of vaccination (injection-site reaction [12], ,anaphylactic-like reaction' [5] and eight other systemic AEs [1,2 each]). Conclusions This review produced no evidence for an unusual rate of any SAE or OMIAE attributable to AVA. It supported an earlier impression that AVA may cause significant local inflammation and should be administered over the deltoid rather than the triceps to avoid direct or compression injury to the ulnar nerve. The subjects of VAERS reports tended to be older than all recipients of AVA. Females generally had and/or reported AEs more often than males, but transient articular reactions were surprisingly more common in males. Variations in the frequency or severity (as judged by hospitalization and/or loss of duty) of reported AEs did not suggest a significant problem with (1) a particular lot of AVA, (2) recurrent AEs after multiple doses or (3) vaccination of persons with a concomitant illness or those given other vaccines or medications. Copyright © 2004 John Wiley & Sons, Ltd. [source] Safety of anthrax vaccine: a review by the Anthrax Vaccine Expert Committee (AVEC) of adverse events reported to the Vaccine Adverse Event Reporting System (VAERS)PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 3 2002John L. Sever Abstract Purpose To assess the safety of a licensed anthrax vaccine given to nearly 400,000 US military personnel, reports of adverse events (AEs) submitted to the Vaccine Adverse Event Reporting System (VAERS) were reviewed and evaluated medically. Methods The Anthrax Vaccine Expert Committee (AVEC), a civilian panel of private-sector physicians and other scientists, reviewed 602 VAERS reports using a Delphic approach (structured expert consensus) to assess the causal relationship between vaccination and the reported AEs and sought to identify unexpected patterns in the occurrence of medically important events. Reports were entered into a database and used to profile AEs with respect to person, type/location, relative frequency, severity/impact, concomitant illness or receipt of other drugs or vaccines, and vaccine lot. Results Nearly half the reports noted a local injection-site AE, with more than one-third of these involving a moderate to large degree of inflammation. Six events qualified as serious AEs (SAEs), and all were judged to be certain consequences of vaccination. Three-quarters of the reports cited a systemic AE (most common: flu-like symptoms, malaise, rash, arthralgia, headache), but only six individual medically important events were judged possibly or probably due to vaccine (aggravation of spondyloarthropathy (2), anaphylactoid reaction, arthritis (2), bronchiolitis obliterans organizing pneumonia) Conclusions Since some cases of local inflammation involved distal paresthesia, AVEC recommends giving subcutaneous injections of AVA over the inferior deltoid instead of the triceps to avoid compression injury to the ulnar nerve. At this time, ongoing evaluation of VAERS reports does not suggest a high frequency or unusual pattern of serious or other medically important AEs. Copyright © 2002 John Wiley & Sons, Ltd. [source] Threshold behaviour of human axons explored using subthreshold perturbations to membrane potentialTHE JOURNAL OF PHYSIOLOGY, Issue 2 2009David Burke The present study explores the threshold behaviour of human axons and the mechanisms contributing to this behaviour. The changes in excitability of cutaneous afferents in the median nerve at the wrist were recorded to a long-lasting subthreshold conditioning stimulus, with a waveform designed to maximize the contribution of currents active in the just-subthreshold region. The conditioning stimulus produced a decrease in threshold that developed over 3,5 ms following the end of the depolarization and then decayed slowly, in a pattern similar to the recovery of axonal excitability following a discharge. To ensure that the conditioning stimulus did not activate low-threshold axons, similar recordings were then made from single motor axons in the ulnar nerve at the elbow. The findings were comparable, and behaviour with the same pattern and time course could be reproduced by subthreshold stimuli in a model of the human axon. In motor axons, subthreshold depolarizing stimuli, 1 ms long, produced a similar increase in excitability, but the late hyperpolarizing deflection was less prominent. This behaviour was again reproduced by the model axon and could be explained by the passive properties of the nodal membrane and conventional Na+ and K+ currents. The modelling studies emphasized the importance of leak current through the Barrett,Barrett resistance, even in the subthreshold region, and suggested a significant contribution of K+ currents to the threshold behaviour of axons. While the gating of slow K+ channels is slow, the resultant current may not be slow if there are substantial changes in membrane potential. By extrapolation, we suggest that, when human axons discharge, nodal slow K+ currents will be activated sufficiently early to contribute to the early changes in excitability following the action potential. [source] Ultrasonographic guided axillary plexus blocks with low volumes of local anaesthetics: a crossover volunteer studyANAESTHESIA, Issue 3 2010P. Marhofer Summary Our study group recently evaluated an ED95 local anaesthetic volume of 0.11 ml.mm,2 cross-sectional nerve area for the ulnar nerve. This prospective, randomised, double-blind crossover study investigated whether this volume is sufficient for brachial plexus blocks at the axillary level. Ten volunteers received an ultrasonographic guided axillary brachial plexus block either with 0.11 (,low' volume) or 0.4 (,high' volume) ml.mm,2 cross-sectional nerve area with mepivacaine 1%. The mean (SD) volume was in the low volume group 4.0 (1.0) and 14.8 (3.8) ml in the high volume group. The success rate for the individual nerve blocks was 27 out of 30 in the low volume group (90%) and 30 out of 30 in the high volume group (100%), resulting in 8 out of 10 (80%) vs 10 out of 10 (100%) complete blocks in the low vs the high volume groups, respectively (NS). The mean (SD) sensory onset time was 25.0 (14.8) min in the low volume group and 15.8 (6.8) min in the high volume group (p < 0.01). The mean (SD) duration of sensory block was 125 (38) min in the low volume group and 152 (70) min in the high volume group (NS). This study confirms our previous published ED95 volume for mepivacaine 1% to block peripheral nerves. The volume of local anaesthetic has some influence on the sensory onset time. [source] Intraneural ganglion cyst: A 200-year-old mystery solvedCLINICAL ANATOMY, Issue 7 2008Robert J. Spinner Abstract We describe the first reported case of an intraneural ganglion cyst, an ulnar ("cubital") intraneural cyst, which, on literature review, dated to 1810. For over 80 years, its original brief description by Beauchęne was wrongly attributed to Duchenne, effectively making the reference and specimen inaccessible to scrutiny. Fortunately, the intact cyst had been safely housed in the Musée Dupuytren, Paris, France, thus permitting its examination. Although originally described as a "serous" cyst, our present understanding of the anatomy of the ulnar nerve and of peripheral nerve pathology allowed us to reinterpret it as a mucin-filled, elbow-level, ulnar intraneural ganglion cyst. In addition to its description as a fusiform cystic enlargement of the nerve, we documented similar enlargement of a lumen-bearing branch, the articular branch at the level of the elbow. Based on our assessment of the specimen and with a modern perspective, we concluded that the origin of the cyst was from the postero-medial aspect of the elbow joint and that its fluid content, having dissected through a capsular defect, followed the path of the articular branch into the parent ulnar nerve. The purpose of this report is to clarify historical misconceptions regarding the pathogenesis of this controversial entity. Clin. Anat. 21:611,618, 2008. © 2008 Wiley-Liss, Inc. [source] Alternative approaches for regional ulnar nerve blockade: A cadaveric studyCLINICAL ANATOMY, Issue 5 2004N. Lizamore Abstract Wrist blockade is a safe and effective alternative to general anesthesia in surgery of hand injuries. With regard to the ulnar nerve, the volar approach is used, where the needle passes through or medial to the flexor carpi ulnaris tendon; however, the ulnar artery is at risk because the needle may accidentally penetrate it, causing profuse bleeding. Alternatively, the wrist may be approached medially, the ulnar approach, and the needle tip placed posterior to the flexor carpi ulnaris tendon. To determine which of these methods may be preferable for avoiding ulnar artery injury, needles were inserted into the wrist area of cadaver hands (n = 57) using the volar and ulnar approaches; detailed dissection of the region around the inserted needles was subsequently carried out. The position of the ulnar nerve relative to the ulnar artery and injury to the artery was documented. Damage to the ulnar artery using the volar approach was 36.8% (21/57 cases) compared to no (0%) injury observed using the ulnar approach. At the level of the wrist crease just proximal to the pisiform bone, the ulnar nerve was medial to the artery in 92.9% (53/57) of cases, medial and posterior in 5.3% (3/57), and anterior to the artery in 1.8% (1/57) of cases. This study suggests that in cases where ulnar artery pulsation is not reliable, the ulnar approach may be preferable for ulnar nerve blockade due to an increased incidence of ulnar artery penetration with the volar approach. Clin. Anat. 17:373,377, 2004. © 2004 Wiley-Liss, Inc. [source] Muscle variations and abnormal branching and course of the ulnar nerve in the forearm and handCLINICAL ANATOMY, Issue 1 2004M.C. Bozkurt Abstract During dissection of the right forearm of a 27-year-old female cadaver, variations in the form and insertion of the palmaris longus muscle were observed. The tendon of the palmaris longus muscle, which demonstrated a centrally placed belly, split into two tendons: one inserted into the palmar aponeurosis and the other into the proximal part of the flexor retinaculum. Additionally, we found an accessory muscle extending between the flexor retinaculum and the tendon of the abductor digiti minimi muscle. This accessory muscle was located deep to the ulnar artery but superficial to the superficial and deep branches of the ulnar nerve at the wrist. Finally, an aberrant branch of the ulnar nerve was identified in the forearm; it traveled distally alongside the ulnar artery and in the palm demonstrated communications with common palmar digital nerves from the ulnar and the median nerves. No variations were observed in the contralateral upper limb. Clin. Anat. 17:64,66, 2004. © 2003 Wiley-Liss, Inc. [source] Ultrasound of peripheral nerves in acromegaly: changes at 1-year follow-upCLINICAL ENDOCRINOLOGY, Issue 2 2009Eugenia Resmini Summary Context, We have previously demonstrated peripheral nerve enlargement in acromegaly. Objective, The aim of this study was to use ultrasound (US) to assess any changes in the peripheral nerves of patients with acromegaly 1 year after the first evaluation. Patients, We prospectively examined the median and ulnar nerve cross-sectional area (CSA) in 34 non-diabetic, patients with acromegaly (18 females and 16 males; 18,79 years) and 34 age-, sex-, BMI-matched controls, using a 17,5 MHz US probe. Intervention, The median nerve was examined at the mid-forearm (MN-f) and at the carpal tunnel (MN-Ct) levels; the ulnar nerve at mid-forearm (UN-f) and at distal arm (UN-a). Patients were grouped according to the clinical control of the disease: ,improved'; ,always controlled'; ,always uncontrolled'; and ,worsened'. Results, The median nerve at mid-forearm (MN-f), the ulnar nerve at mid-forearm (UN-f) and at distal arm (UN-a) were significantly reduced after 1-year follow-up in all patients (P < 0·001, P < 0·008, P < 0·012, respectively). In the ,improved' group, there was a significant reduction of median nerve CSA examined at mid-forearm (MN-f) (P = 0·02), and distal arm ulnar nerve CSA (UN-a) (P = 0·002). In the other groups no statistically significant differences in ultrasound parameters were recorded. However, UN-a, UN-f, MN-f, MN-ct were still significantly higher in all groups compared with controls (P < 0·001). Conclusion, These data demonstrate that median and ulnar nerves CSA are reduced after 1 year follow-up, in line with the reduction of GH/IGF-I levels. However, as the control of the disease incompletely reverts nerve enlargement, this phenomenon could be only partially reversible. [source] Effect of pneumatic power tool use on nerve conduction velocity across the wristHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 4 2005John Rosecrance The purpose of this study was to determine if the use of pneumatic power tools altered electrophysiologic properties of the median and ulnar nerves at the wrist during the work shift. Sensory nerve conduction velocities were measured in hands of workers before work and then at 2-hour intervals during the workday. Ten workers exposed to pneumatic power tool use and 10 workers not exposed to intensive hand activity were evaluated. The conduction velocities slowed significantly across the wrist in the median and ulnar nerves among workers using pneumatic tools but not among control workers. This investigation demonstrated that short-term exposure to highly intensive hand tasks causes significant slowing in nerve conduction velocity across the wrist. © 2005 Wiley Periodicals, Inc. Hum Factors Man 15: 339,352, 2005. [source] A comparison of ultrasound-guided supraclavicular and infraclavicular blocks for upper extremity surgeryACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2009Z. J. KOSCIELNIAK-NIELSEN Background: Ultrasound (US)-guided supraclavicular or infraclavicular blocks are commonly used for upper extremity surgery. The aims of this randomized study were to compare the block performance and onset times, effectiveness, incidence of adverse events and patient's acceptance of US-guided supraclavicular or infraclavicular blocks. We hypothesized that the supraclavicular approach, being more superficial and easier to visualize using a 10 MHz transducer, will produce a faster and a more extensive sensory block. Methods: One hundred and twenty patients were randomized to two equal groups: supraclavicular (S) and infraclavicular (I). Each patient received a mixture containing equal volumes of ropivacaine 7.5 mg/ml and mepivacaine 20 mg/ml with adrenaline 5 ,g/ml, 0.5 ml/kg body weight (minimum 30 ml, maximum 50 ml). The sensory score (anaesthesia , 2 points, analgesia , 1 point and pain , 0 point) of the seven terminal nerves was assessed every 10 min. Patients were declared ready for surgery when they had an effective surgical block , anaesthesia or analgesia of the five nerves below the elbow. Thirty minutes after the block, the unblocked nerves were supplemented. The block performance and latency times, surgical effectiveness, adverse events and patient's acceptance were recorded. Results: Significantly more patients in the I group were ready for surgery 20 and 30 min after the block. The mean block performance time was 5.7 min in the S group and 5.0 min in the I group (NS). Block effectiveness was superior in the I group: 93% vs. 78% in the S group (P=0.017). The S group patients had a significantly poorer block of the median and ulnar nerves, but a better block of the axillary nerve. Sensory scores at 10, 20 and 30 min were not significantly different. Thirty-two patients in the S group vs. nine patients in the I group experienced transient adverse events (P<0.0001). Patients' acceptance of the block was similar in both groups. Conclusions: Infraclavicular block had a faster onset, better surgical effectiveness and fewer adverse events. Block performance time and patients' acceptance of the procedure were similar in both groups. [source] A randomized controlled trial evaluating an alternative mouse or forearm support on change in median and ulnar nerve motor latency at the wristAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 4 2009Craig F. Conlon MD Abstract Background The purpose of this study was to determine the effects of an alternative mouse and/or a forearm support board on nerve function at the wrist among engineers. Methods This randomized controlled intervention trial followed 206 engineers for 1 year. Distal motor latency (DML) at baseline and follow-up was conducted for the median and ulnar nerves at the right wrist. Results One hundred fifty-four subjects agreed to a nerve conduction study at the beginning and end of the study period. Those who received the alternative mouse had a protective effect (OR,=,0.47, 95% CI 0.22,0.98) on change in the right ulnar DML. There was no significant effect on the median nerve DML. The forearm support board had no significant effect on the median or ulnar nerve DML. Conclusions In engineers who use a computer for more than 20 hr per week, an alternative mouse may have a protective effect for ulnar nerve function at the wrist. No protective effect of a forearm support board was found for the median nerve. Am. J. Ind. Med. 52:304,310, 2009. © 2009 Wiley-Liss, Inc. [source] Communications between the palmar digital branches of the median and ulnar nerves: A study in human fetuses and a review of the literature,CLINICAL ANATOMY, Issue 2 2010Nadire Unver Dogan Abstract In this study, median nerves (MNs) and ulnar nerves (UNs) were dissected in 200 palmar sides of hands (left and right) of 100 (50 male, 50 female) spontaneously aborted fetuses with no detectable malformations. The fetuses, whose gestational ages ranged from 13 to 40 weeks, were dissected under an operating microscope. The MN divided first into a lateral ramus and a medial ramus and then formed a common digital nerve. The first common digital nerve trifurcated in all of the studied cases. The branching patterns were classified into two types (Type 1 and Type 2) based on the relationship with the flexor retinaculum (behind/distal of it). A communication branch between the UNs and MNs in the palmar surface of the hand was found in 59 hands (29.5%). The proper palmar digital nerves were numbered from p1 to p10, starting from the radial half of the thumb to the ulnar half of the little finger, and these nerves exhibited six types of variations. The present data obtained from human fetuses will aid in elucidating the developmental anatomy of the nervous system and provide hand surgeons with a more complete anatomical picture to help them to avoid iatrogenic injuries. Clin. Anat. 23:234,241, 2010. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||