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Wrist Extension (wrist + extension)
Selected AbstractsThe effect of strength training on the force of twitches evoked by corticospinal stimulation in humansACTA PHYSIOLOGICA, Issue 2 2009T. J. Carroll Abstract Aim:, Although there is considerable evidence that strength training causes adaptations in the central nervous system, many details remain unclear. Here we studied neuromuscular responses to strength training of the wrist by recording electromyographic and twitch responses to transcranial magnetic stimulation (TMS) and cervicomedullary stimulation of the corticospinal tract. Methods:, Seventeen participants performed 4 weeks (12 sessions) of strength training for the radial deviator (RD) muscles of the wrist (n = 8) or control training without external load (n = 9). TMS recruitment curves were constructed from stimuli at five to eight intensities ranging between 15% below resting motor threshold and maximal stimulator output, both at rest and during isometric wrist extension (EXT) and RD at 10% and 50% of maximal voluntary contraction (MVC). Responses to weak TMS and cervicomedullary stimulation (set to produce a response of 10% maximal M wave amplitude during 10% MVC EXT contraction) were also compared at contraction strengths ranging from 10% to 75% MVC. Results:, Isometric strength increased following strength training (10.7% for the RD MVC, 8.8% for the EXT MVC), but not control training. Strength training also significantly increased the amplitude of TMS- and cervicomedullary-evoked twitches during low-force contractions. Increases in the force-generating capacity of the wrist extensor muscles are unlikely to account for this finding because training did not affect the amplitude of twitches elicited by supra-maximal nerve stimulation. Conclusion:, The data suggest that strength training induces adaptations that increase the net gain of corticospinal-motor neuronal projections to the trained muscles. [source] Therapeutic effects of functional electrical stimulation of the upper limb of eight children with cerebral palsyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2000P A Wright BSc PhD Functional electrical stimulation (FES) of the upper limb has been used for patients with a variety of neurological conditions, although few studies have been conducted on its use on the upper limb of children with cerebral palsy (CP). The aim of this study was to investigate the effect of cyclic FES on the wrist extensor muscles of a group of eight children (five boys, three girls) with hemiplegic CP (mean age 10 years). The study design involved a baseline (3 weeks), treatment (6 weeks), and follow-up (6 weeks). FES was applied for 30 minutes daily during the treatment period of the study. Improvements in hand function (p,0.039) and active wrist extension (p=0.031) were observed at the end of the treatment period. These improvements were largely maintained until the end of the follow-up period. No significant change was observed in the measurements of wrist extension moment during the treatment period (p=0.274). Hand function in this group of children improved after they were exposed to FES of wrist extensor muscles. This suggests that FES could become a useful adjunct therapy to complement existing management strategies available for this patient population. [source] Longitudinal excursion and strain in the median nerve during novel nerve gliding exercises for carpal tunnel syndromeJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2007Michel W. Coppieters Abstract Nerve and tendon gliding exercises are advocated in the conservative and postoperative management of carpal tunnel syndrome (CTS). However, traditionally advocated exercises elongate the nerve bedding substantially, which may induce a potentially deleterious strain in the median nerve with the risk of symptom exacerbation in some patients and reduced benefits from nerve gliding. This study aimed to evaluate various nerve gliding exercises, including novel techniques that aim to slide the nerve through the carpal tunnel while minimizing strain ("sliding techniques"). With these sliding techniques, it is assumed that an increase in nerve strain due to nerve bed elongation at one joint (e.g., wrist extension) is simultaneously counterbalanced by a decrease in nerve bed length at an adjacent joint (e.g., elbow flexion). Excursion and strain in the median nerve at the wrist were measured with a digital calliper and miniature strain gauge in six human cadavers during six mobilization techniques. The sliding technique resulted in an excursion of 12.4 mm, which was 30% larger than any other technique (p,,,0.0002). Strain also differed between techniques (p,,,0.00001), with minimal peak values for the sliding technique. Nerve gliding associated with wrist movements can be considerably increased and nerve strain substantially reduced by simultaneously moving neighboring joints. These novel nerve sliding techniques are biologically plausible exercises for CTS that deserve further clinical evaluation. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:972,980, 2007 [source] Total obstetric brachial plexus palsy: Results and strategy of microsurgical reconstructionMICROSURGERY, Issue 3 2010Tarek A. El-gammal M.D. From 2000 to 2006, 35 infants with total obstetric brachial plexus palsy underwent brachial plexus exploration and reconstruction. The mean age at surgery was 10.8 months (range 3,60 months), and the median age was 8 months. All infants were followed for at least 2.5 years (range 2.5,7.3 years) with an average follow-up of 4.2 years. Assessment was performed using the Toronto Active Movement scale. Surgical procedures included neurolysis, neuroma excision and interposition nerve grafting and neurotization, using spinal accessory nerve, intercostals and contralateral C7 root. Satisfactory recovery was obtained in 37.1% of cases for shoulder abduction; 54.3% for shoulder external rotation; 75.1% for elbow flexion; 77.1% for elbow extension; 61.1% for finger flexion, 31.4% for wrist extension and 45.8% for fingers extension. Using the Raimondi score, 18 cases (53%) achieved a score of three or more (functional hand). The mean Raimondi score significantly improved postoperatively as compared to the preoperative mean: 2.73 versus 1, and showed negative significant correlation with age at surgery. In total, obstetrical brachial plexus palsy, early intervention is recommended. Intercostal neurotization is preferred for restoration of elbow flexion. Tendon transfer may be required to improve external rotation in selected cases. Apparently, intact C8 and T1 roots should be left alone if the patient has partial hand recovery, no Horner syndrome, and was operated early (3- or 4-months old). Apparently, intact nonfunctioning lower roots with no response to electrical stimulation, especially in the presence of Horner syndrome, should be neurotized with the best available intraplexal donor. © 2010 Wiley-Liss, Inc. Microsurgery, 2010. [source] Vibration prolongs the cortical silent period in an antagonistic muscleMUSCLE AND NERVE, Issue 6 2009Christian Binder MD Abstract We tested whether the silent period, an indicator of inhibitory neuronal activity, is modulated by muscle vibration. Vibration was applied to the right extensor carpi radialis (ECR) muscle in 17 healthy subjects and, as a control experiment, to the dorsal terminal phalanges in 5 subjects. Data before vibration were compared with those during vibration. The cortical silent period (CSP) was evoked by transcranial magnetic stimuli (TMS) during voluntary wrist flexion or during voluntary wrist extension. TMS-evoked motor potentials (MEPs) of the flexor carpi radialis (FCR) muscle were recorded during muscle relaxation. The mixed nerve silent period (MNSP) was obtained by electrical stimulation of the median nerve during wrist flexion. ECR vibration induced a significant prolongation of the CSP in FCR. CSP increases induced by vibration of the dorsal terminal phalanges were significantly less pronounced. In ECR, the CSP tended to be shortened. MEPs and MNSP remained unchanged. We conclude that vibration enhances inhibitory neuronal properties in a non-vibrated antagonistic muscle, presumably at a supraspinal level. These results may be relevant for the treatment of spasticity of the upper extremity. Muscle Nerve, 2009 [source] Assessment of Finger Forces and Wrist Torques for Functional Grasp Using New Multichannel Textile NeuroprosthesesARTIFICIAL ORGANS, Issue 8 2008Marc Lawrence Abstract:, New multichannel textile neuroprotheses were developed, which comprise multiple sets of transcutaneous electrode arrays and connecting wires embroidered into a fabric layer. The electrode arrays were placed on the forearm above the extrinsic finger flexors and extensors. Activation regions for selective finger flexion and wrist extension were configured by switching a subset of the array elements between cathode, anode, and off states. We present a new isometric measurement system for the assessment of finger forces and wrist torques generated using the new neuroprostheses. Finger forces (from the middle phalanxes) were recorded using five load cells mounted on a "grasp handle" that can be arbitrarily positioned in space. The hand and the grasp handle were rigidly mounted to a 6-degree of freedom load cell, and the forces and torques about the wrist were recorded. A vacuum cushion was used to comfortably fixate the forearm. The position and orientation of the forearm, wrist, fingers, and handle were recorded using a new three-dimensional position measurement system (accuracy <±1 mm). The measurement system was integrated into the real-time multichannel transcutaneous electrode environment, which is able to control the spatiotemporal position of multiple activation regions. Using the combined system and textile neuroprosthesis, we were able to optimize the activation regions to produce selective finger and wrist articulation, enabling improved functional grasp. [source] | |||||||||||||