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2.
J Hand Surg Eur Vol ; 39(7): 719-26, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24563498

RESUMEN

The purpose of this systematic review was to determine the outcome of interphalangeal (IP) joint motion in children undergoing open surgical release, splinting, and passive exercising therapy for the treatment of paediatric trigger thumb. We conducted an online literature search of seven major databases. Only studies with a mean follow-up of at least 12 months were considered for inclusion. Seventeen retrospective studies and one prospective study met all the inclusion criteria. They reported on the results of surgery (634 children, 759 thumbs), splinting (115 children, 138 thumbs), and passive exercising (89 children, 108 thumbs). The mean follow-up periods were 59 (surgery), 23 (splinting), and 76 months (exercising), respectively. Full IP joint motion without residual triggering was achieved in 95% of all children undergoing surgery, in 67% of children treated with continuous splinting, and 55% after passive exercising. Based on the low level of evidence available, it seems that open surgery resulted in more reliable and rapid outcomes compared with nonoperative treatment.


Asunto(s)
Terapia por Ejercicio , Férulas (Fijadores) , Trastorno del Dedo en Gatillo/cirugía , Niño , Preescolar , Articulaciones de los Dedos , Humanos , Rango del Movimiento Articular , Recuperación de la Función , Resultado del Tratamiento , Trastorno del Dedo en Gatillo/fisiopatología
4.
Schmerz ; 23(6): 592-9, 2009 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-19756767

RESUMEN

INTRODUCTION: Treatment with intrathecal baclofen (ITB) is an important part of the complex therapy of patients with cerebral spasticity aiming to improve the motoric functions and to reduce pain intensity. MATERIAL AND METHODS: ITB was started in the Orthopaedic Hospital in Speising in 1999. From 1999 to 2006 a total of 15 children aged 3 to 16 years old were selected for this special treatment. RESULTS: The average degree of spasticity according to Ashworth (scale 1-5) could be reduced by ITB from 4.38 to 3.0, the time spent sitting could be increased from 3.3 to 5.8h per day and the pain intensity (VAS 1-10) could be reduced from 4.2 to 0.6. The time necessary for nursing treatment was shortened from 7.5 to 3.4 (VAS 1-10). Also improved was the emotional situation, the ability to swallow, the posture of the head and the concentration ability. CONCLUSION: ITB provides neuromodulation even in pediatric patients with complex neuromotoric spasticity.


Asunto(s)
Baclofeno/administración & dosificación , Parálisis Cerebral/tratamiento farmacológico , Relajantes Musculares Centrales/administración & dosificación , Adolescente , Parálisis Cerebral/diagnóstico , Niño , Preescolar , Evaluación de la Discapacidad , Relación Dosis-Respuesta a Droga , Diseño de Equipo , Femenino , Estudios de Seguimiento , Humanos , Bombas de Infusión Implantables , Inyecciones Espinales , Masculino , Ahogamiento Inminente/complicaciones , Examen Neurológico/efectos de los fármacos , Dimensión del Dolor
5.
Handchir Mikrochir Plast Chir ; 40(1): 8-12, 2008 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-18322893

RESUMEN

Peromelia is a rare but mutilating congenital deformity representing failure of formation of parts of the upper limb. The deformity is presented unilaterally in the vast majority of the cases. Usually, these children are totally healthy beside from the deformity and are not seriously handicapped by the deformity. Correction of the deformity by hand- or forearm transplantation is not yet possible. Treatment consists of support with prosthesis in case of missing upper- or forearm and construction of fingers by toe-to-hand transplantation in case of missing fingers and hand. Treatment is not mandatory as the children use the stump in combination with their unimpaired upper limb for bimanual daily life activities. The mutilating aspect of the deformity frequently does impair especially parents but also the children to a higher extent than the actual functional disability. Psychological aid is recommended to support children and parents in managing their life with this severe deformity.


Asunto(s)
Deformidades Congénitas de las Extremidades Superiores , Miembros Artificiales , Austria/epidemiología , Niño , Deformidades Congénitas de la Mano/epidemiología , Deformidades Congénitas de la Mano/psicología , Deformidades Congénitas de la Mano/cirugía , Humanos , Incidencia , Lactante , Recién Nacido , Padres/psicología , Polidactilia , Sindactilia , Dedos del Pie/trasplante , Deformidades Congénitas de las Extremidades Superiores/psicología , Deformidades Congénitas de las Extremidades Superiores/cirugía
6.
Acta Neurochir Suppl ; 100: 141-3, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17985564

RESUMEN

BACKGROUND: We report about our experiences using a single supraclavicular incision at the base of the neck for Thoracic Outlet Syndrome (TOS) surgery. METHODS: 10 patients aged between 12 and 59 years (mean 31 years) underwent 12 times a TOS procedure. Patients suffered from compression of their brachial plexus with main affection of the ulnar nerve (9 out of 12 cases). Electroneurography was positive for TOS 4 times in 3 patients, in other 3 patients additionally a distal nerve compression syndrome was evident. In 7 cases (5 patients) a cervical rib was present on X-ray. In 10 cases (8 patients) the subclavian artery showed a stenosis behind the clavicle on MRI-angiography. In all cases the brachial plexus was prepared and a complete scalenotomy was performed. Whenever present the cervical rib was resected and in 2 cases the first rib (1 with/1 without cervical rib) was taken out. RESULTS: The surgical procedures did not cause relevant complications. All patients were without discomfort within 6 months, including the nerve regeneration disturbances. One patient suffered from TOS recurrence 10 months after surgery (scalenotomy without resection of the 1st rib). CONCLUSION: The single supraclavicular incision provided sufficient access to the structures of the brachial plexus, the subclavian artery and the cervical and 1st rib in all cases. The procedure produced not only sufficient pain relief and normalized extremity function but also a cosmetically acceptable, nearly invisible scar.


Asunto(s)
Procedimientos Neuroquirúrgicos/métodos , Síndrome del Desfiladero Torácico/cirugía , Adolescente , Adulto , Niño , Femenino , Mano/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Regeneración Nerviosa , Procedimientos Neuroquirúrgicos/efectos adversos , Dolor Postoperatorio/fisiopatología , Trastornos de la Sensación/etiología , Trastornos de la Sensación/fisiopatología , Síndrome del Desfiladero Torácico/fisiopatología , Resultado del Tratamiento
7.
Eur J Vasc Endovasc Surg ; 27(6): 635-9, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15121115

RESUMEN

OBJECTIVES: To evaluate the feasibility and long-term outcome of distal arterial reconstruction combined with free muscle flap transfer for patients who would otherwise have undergone major amputation. METHODS: Between 1996 and 2001, 27 reconstructions using autologous vein were performed in 25 patients. Seventeen of these patients had diabetes mellitus. Gracilis, rectus abdominis and latissimus dorsi muscles were used as free flaps, covered with split-thickness skin grafts. RESULTS: Eighty-five percent of patients had a patent graft and viable muscle flap after 1-month. Mean follow-up was 51 months (4-72 months). At the time of follow-up 77% of reconstructions were patent and 70% of patients regained full functional capacity of their lower extremities. CONCLUSION: Limb-salvage by distal arterial reconstruction and free muscle flap transfer, is feasible with low mortality and morbidity and provides excellent long-term results with regard to graft patency and functional status.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Pierna/irrigación sanguínea , Recuperación del Miembro/métodos , Colgajos Quirúrgicos , Venas/trasplante , Bases de Datos Factuales , Angiopatías Diabéticas/cirugía , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Grado de Desobstrucción Vascular
8.
Calcif Tissue Int ; 74(2): 181-6, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14639469

RESUMEN

Chondrocytes in the growth plate undergo a characteristic sequel of differentiation processes, finally leading in their death by apoptosis. The mechanisms that mediate these remarkable biological phenomenon are still widely unknown. For this study, growth plates from five resected polydactylic infantile fingers were taken and immunostained for APO-1 and Caspase-8, two apoptosis-mediating proteins. The expression of both proteins was examined in the resting zone, proliferating zone, and hypertrophic zone, representing the maturation stages of the growth plate. Positive cells for APO-1 and Caspase-8 were found in all zones of the physis with a significant increase from the resting to the hypertrophic zone (from 17.4% to 33.067% for APO-1 and from 13.17% to 28.22% for Caspase-8). Our findings suggest that both APO-1 and Caspase-8 are involved in chondrocyte development in the growth plate, predominantly near to the closure area.


Asunto(s)
Caspasas/metabolismo , Placa de Crecimiento/metabolismo , Receptor fas/metabolismo , Apoptosis , Caspasa 8 , Recuento de Células , Condrocitos/citología , Condrocitos/metabolismo , Dedos/cirugía , Placa de Crecimiento/citología , Humanos , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Lactante
9.
Laryngorhinootologie ; 81(8): 568-72, 2002 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-12189573

RESUMEN

A rare case of adenosquamous carcinoma in a 74 year-old man is reported. Presenting as a nodule on the soft palate, diagnosis was prolonged because of the benign macroscopic aspect. CT-scan and MR-tomography showed an encapsulated lesion but biopsy and histologic examination revealed the typical features of adenosquamous carcinoma. The tumour consisted of adenocarcinoma and squamous cell carcinoma in close proximity to minor salivary glands of which the tumour seemed to have its origin. This entity, although rare in the head and neck region has been documented to be very aggressive with early regional and hematogenic metastasis. Therefore it has to be distinguished from other tumours, especially from mucoepidermoid carcinomas of the salivary glands, which have a better prognosis. Adenosquamous carcinoma is considered to have poor radiosensitivity and chemotherapeutic approaches have also not been successful in the literature. In our case radical surgical therapy was performed by excision of the whole soft palate and bilateral neck dissection. This resulted in total removal of the tumour but revealed bilateral lymph node metastases. Vital functions were saved by reconstruction of the palate with a free vascularized tensor-fasciae-latae-perforator-flap. For the first time in a case of adenosquamous carcinoma carcinoembryonic antigen in serum was monitored. A pretherapeutical 29-fold elevation resulted in a marked decrease after surgery, but supranormal values indicated remaining tumour burden which was found in metastases in the lung. Because of the limitations in therapy, early histologic diagnosis is most important in this highly malignant tumour.


Asunto(s)
Carcinoma Adenoescamoso , Neoplasias Palatinas , Anciano , Biopsia , Antígeno Carcinoembrionario/análisis , Carcinoma Adenoescamoso/diagnóstico , Carcinoma Adenoescamoso/diagnóstico por imagen , Carcinoma Adenoescamoso/patología , Carcinoma Adenoescamoso/cirugía , Diagnóstico Diferencial , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/secundario , Metástasis Linfática , Imagen por Resonancia Magnética , Masculino , Neoplasias Palatinas/diagnóstico , Neoplasias Palatinas/diagnóstico por imagen , Neoplasias Palatinas/patología , Neoplasias Palatinas/cirugía , Paladar Blando/patología , Pronóstico , Colgajos Quirúrgicos , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
10.
Artif Organs ; 25(6): 467-74, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11453877

RESUMEN

A newly developed implantable stimulator with 20 output channels, mainly intended for the stimulation of lower extremities in paraplegics, was implanted in 6 sheep over a time period of 26 weeks. Five epineural electrodes each were used to contact various nerves at different locations to elicit hip and knee extension and flexion and to make carrousel and selective stimulation possible. Different electrode application strategies in view of paraplegic standing and walking were investigated. Additional implanted electrodes allowed M-wave monitoring for selectivity investigations in 3 sheep. Stimulator, electrode leads, and electrodes proved to be reliable. Selective stimulation with electrodes placed on the trunk of the sciatic nerve could be demonstrated but with bad reproducibility. Histological investigation of the tissues surrounding electrodes and leads showed the expected stable foreign body response. Strong hip and knee extension could be gained in all cases while only weak flexion forces could be elicited in most cases. Muscle biopsies showed that daily stimulation for 8 h at threshold level caused an increase in muscle Type I fibers and a decrease in Type IIc fibers. Implants and electrodes fulfill the most important functional and biological criteria for their clinical application for paraplegic walking. The intention to provide selective flexion functions via epineural stimulation could not be demonstrated sufficiently in this animal model.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Pierna/fisiología , Músculo Esquelético/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/terapia , Animales , Electrodos , Ovinos
11.
Surg Radiol Anat ; 23(2): 117-21, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11462859

RESUMEN

The carpal tunnel syndrome (CTS) is the most common peripheral entrapment neuropathy in human. The diagnosis is based on symptoms and on physical examination and is supported by nerve conduction tests. The aim of this study was to evaluate the precision and the valence of ultrasound (US) for CTS. An anatomic study was performed on 40 wrists of 20 unfixed human cadavers. The carpal tunnel and its important structures and contents were imaged and measured by ultrasound (7.5-MHz high resolution probe). The dorsopalmar diameter (DPD), the radioulnar diameter (RUD), the perimeter (P) and the cross-sectional area (A) were determined for the carpal canal and for the median nerve. These US images and measurements were directly compared with anatomic cross-sections gained from the same wrists at the same level. Our results showed that ultrasound is a very precise method to display the anatomy of the carpal tunnel and of the median nerve and thus the conditions of the median nerve. Significant differences could not be detected for each of these parameters either for the carpal tunnel or the median nerve. (Ultrasound: cross-sectional area of carpal tunnel: 162.4 +/- 29.3 mm2 and of the median nerve: 9.2 +/- 2.4 mm2; anatomy: cross-sectional area of carpal tunnel: 168.4 +/- 31.2 mm2 and of median nerve: 9.4 +/- 2.2 mm2).


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico por imagen , Síndrome del Túnel Carpiano/diagnóstico , Anciano , Anatomía Transversal , Cadáver , Femenino , Humanos , Masculino , Nervio Mediano/anatomía & histología , Nervio Mediano/diagnóstico por imagen , Ultrasonografía , Muñeca/anatomía & histología , Muñeca/diagnóstico por imagen
12.
Handchir Mikrochir Plast Chir ; 33(2): 121-8, 2001 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-11329890

RESUMEN

The goal of the presented carpal tunnel syndrome (CTS) follow-up study was to compare the clinical value of the Millesi hand function score with the "Pressure Specifying Sensory Device" (PSSD) introduced by A. L. Dellon using self-administered patient questionnaires. 25 patients (10 male, 15 female) with an electrodiagnostically confirmed CTS were enrolled in this study, performing one preoperative and five postoperative examinations over 24 weeks. 12 of the 25 patients underwent an "open" two-portal carpal tunnel release with two minimal incisions (group OT); the other 13 patients were treated with a two-portal endoscopic carpal tunnel release (group ET). Additionally, in eleven out of the twelve patients of group OT, an epineuriotomy of the median nerve was performed during the same session. Concerning preoperative data of the Millesi score and the PSSD, no statistically significant differences were found between group OT and ET. However, preoperative comparison with the contralateral hand demonstrated a reduction in hand function of 15% and an increase in the pressure perception threshold of 41% compared to normative data could be measured with the PSSD. The subjective functional value of the hand was objectively evacuated using the Levine score. In the second postoperative week, a significant decrease in hand function could be obtained with the Millesi score in group OT. In group ET, the decrease in hand function representing the operative trauma was significantly lower than in group OT. Data of the static one- and two-point pressure perception threshold revealed a statistically significant improvement of the sensibility in both groups. The results of the Millesi score recorded at the last examination in the 24th postoperative week showed an improvement in hand function in both groups compared to preoperative data. Concerning static one- and two-point measurements with the PSSD, distinct improvements compared to the preoperative data could also be detected in both groups although significant differences between group OT and ET were evident: Data of group OT regarding the whole postoperative course demonstrate a continuous improvement in sensibility of the index finger. In contrast, the analysis of the PSSD measurements in group ET revealed an increase in all the parameters starting in the sixth postoperative week and ending with significantly worse static one- and two-point threshold measurements than in group OT. On the other hand, data of self-administered patient questionnaires using the Levine Score revealed significant improvements in hand function and reduction in pain intensity in both groups compared to preoperative results. Differences between both groups at the end of the examination course were not evident. In conclusion, the Millesi hand score with its emphasis on the motor function proved to be a reliable method to record the severity of CTS preoperatively, the severity of the surgical trauma and changes in the course of rehabilitation of the affected hand. A good correlation was found between data obtained with the Millesi Score and the self-administered patient questionnaires according to Levine. But when compared with the PSSD, both methods could not directly document the preoperative status and postoperative changes of the median nerve. Preoperative static two-point pressure threshold measurements with the PSSD confirmed their status as a screening parameter as published by A. L. Dellon. In the postoperative course of group ET, a distinct worsening in the sensibility of the index and little finger could only be detected with the PSSD before the patients noticed the onset of related symptoms.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico , Diagnóstico por Computador , Fuerza de la Mano/fisiología , Destreza Motora/fisiología , Trastornos de la Sensación/diagnóstico , Adulto , Anciano , Síndrome del Túnel Carpiano/fisiopatología , Síndrome del Túnel Carpiano/cirugía , Femenino , Humanos , Masculino , Nervio Mediano/fisiopatología , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/fisiopatología , Valor Predictivo de las Pruebas , Trastornos de la Sensación/fisiopatología
13.
Handchir Mikrochir Plast Chir ; 33(2): 89-94, 2001 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-11329896

RESUMEN

During the last years, a large number of newly designed flaps have been presented, suitable to cover defects of the hand. Some of them, namely the retrograde interossea-posterior and the lateral arm flaps, found their way into daily clinical routine. They even seem to have replaced the standard flaps for defect coverage to the hand, the pedicled groin flap and the radial forearm flap. Especially the radial forearm flap seems to become an obsolete procedure, as it requires sacrificing a main forearm artery. Three patients are presented who suffered from complex injuries to their hands and were treated with radial forearm flaps in a single-stage primary procedure. In two hands, the arterial palmar arches and the soft-tissues of the palm were reconstructed by use of a distally pedicled radial forearm flap. Collateral arteries of ischemic fingers were implanted into the flap artery to achieve revascularization and a vein graft was interposed between the stumps of the radial artery to reestablish an orthograde blood flow. A free radial forearm flap harvested from the contralateral uninjured forearm was used to replant a torn-out forearm. In all cases, primary healing was achieved without complications. Primary treatment of complex injuries to the hand and forearm often requires revascularization of ischemic parts of the limb and coverage of large soft-tissue defects at the same time. The radial forearm flap, either as a distally pedicled flap or as a free flap, meets all the needs or in particular is appropriate to perform such demanding primary procedures. The destruction of the arterial palmar arches does not present a contraindication against the use of a distally pedicled radial forearm flap, but actually is a strong indication to reconstruct the radial artery by a vein graft.


Asunto(s)
Traumatismos de la Mano/cirugía , Traumatismos de los Tejidos Blandos/cirugía , Colgajos Quirúrgicos/irrigación sanguínea , Adolescente , Adulto , Amputación Traumática/cirugía , Angiografía , Traumatismos de los Dedos/cirugía , Traumatismos del Antebrazo/cirugía , Humanos , Masculino , Persona de Mediana Edad , Arteria Radial/diagnóstico por imagen , Arteria Radial/cirugía , Reoperación , Reimplantación , Venas/trasplante
14.
Biomed Tech (Berl) ; 45(4): 93-7, 2000 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-10829543

RESUMEN

When using functional electrical stimulation (FES), correct adjustment of stimulation parameters, and monitoring of the stimulated muscle is mandatory if tissue damage is to be avoided. Although several FES systems are already in regular use, a method for direct muscle monitoring is still lacking. This paper investigates the suitability of the electromyogram (EMG) for such a purpose. In six sheep, the right latissimus dorsi muscle (LDM) and the associated thoracodorsal nerve were exposed. Stimulation was effected via electrodes placed on the nerve. Three electrodes were placed in the LDM for EMG recording, and the tendon was connected to a force transducer for isometric force measurement. Stimulation was applied for one second (burst), followed by a three-second pause. The stimulation current was increased in 0.2 mA steps, starting at 0 mA and ending at 4 mA. Throughout the investigation, the EMG signal was monitored with an oscilloscope. In addition, the EMG signal and the force transducer signal were recorded for subsequent analysis. An analysis of the data of all six sheep revealed an almost linear relationship between muscle force and m-wave amplitude (magnitude of r = 0.95, p < 0.001). M-wave monitoring during EMG recording with three intramuscular electrodes is a reliable method of monitoring FES-induced muscle activity, but the absolute force cannot be measured.


Asunto(s)
Estimulación Eléctrica/instrumentación , Electromiografía/instrumentación , Monitoreo Fisiológico/instrumentación , Músculo Esquelético/inervación , Animales , Electrodos , Femenino , Humanos , Microcomputadores , Ovinos , Procesamiento de Señales Asistido por Computador/instrumentación
15.
Eur Surg Res ; 32(2): 129-34, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10810220

RESUMEN

As part of a study examining the use of a skeletal muscle ventricle for cardiac assistance in sheep, a new concept of muscle preconditioning was put into practice. We aimed to produce a latissimus dorsi muscle (LDM) capable of performing chronic work immediately after the construction of a skeletal muscle ventricle. The left LDM was detached from the thoracic wall, divided longitudinally and reattached in situ to achieve vascular delay. The right LDM was left unaffected. Thereafter, preconditioning of both LDM was started according to the clinically approved stimulation protocol for cardiomyoplasty. Preconditioning of the unaffected right LDM in situ resulted in a complete muscle fiber transformation with no signs of degeneration or necrosis. Mobilization of the left LDM before preconditioning led to a distinct damage of the muscle. During conditioning, the increase in burst duration from 2 to 3 impulses in sheep A and from 3 to 5 impulses in sheep B resulted in a homogenous degeneration of the muscle fibers of the left LDM. Histomorphological analysis showed a dramatic increase in the percent perimysial and endomysial connective tissue. The applied concept of muscle prefabrication proved to be a failure. Muscle splitting and mobilization followed by vascular delay and in situ conditioning as a concept of muscle prefabrication should be strictly avoided.


Asunto(s)
Ventrículo de Músculo Esquelético , Animales , Cardiomioplastia , Estimulación Eléctrica/efectos adversos , Estimulación Eléctrica/métodos , Femenino , Fibras Musculares de Contracción Lenta/patología , Ovinos , Ventrículo de Músculo Esquelético/patología , Ventrículo de Músculo Esquelético/fisiología
16.
Artif Organs ; 23(9): 860-8, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10491035

RESUMEN

Diaphragm pacing has been used to restore respiration in approximately 1,000 patients worldwide suffering from high quadriplegia or from central alveolar hypoventilation syndrome. Compared with conventional mechanical ventilation, electrophrenic respiration (EPR) reduces the risk of pulmonary infections and increases the mobility of patients. Voluntary activation of the pacemaker during speech would improve patients' quality of life and allow application of EPR in a more physiological way. An animal study was performed to investigate the electromyogram (EMG) of the posterior cricoarytenoid (PCA) muscle and the movement of the glottis via impedance measurement (electroglottography) with the aim to examine reproducibility and stability of the recordings from the PCA muscle as a potential biological trigger for a phrenic pacemaker. The EMG of the PCA muscle was recorded via implanted electrodes for a 200 day period. The EMG signal proved stable for that period, artifacts caused by movements can be suppressed, and swallowing can be detected. In contrast, impedance measurement to detect movement of the glottis proved not useful. Based on the results of this study, the use of the PCA EMG as a biological trigger for a phrenic pacemaker has to be considered a realistic option.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Electromiografía , Músculos Laríngeos/fisiología , Nervio Frénico/fisiología , Animales , Artefactos , Deglución/fisiología , Diafragma/fisiología , Electrodos Implantados , Electromiografía/instrumentación , Diseño de Equipo , Femenino , Estudios de Seguimiento , Glotis/fisiología , Estudios Longitudinales , Movimiento , Platino (Metal) , Reproducibilidad de los Resultados , Respiración , Terapia Respiratoria , Ovinos , Acero Inoxidable
17.
Artif Organs ; 23(5): 399-402, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10378928

RESUMEN

Chronic activation of skeletal muscle is used clinically in representative numbers for diaphragm pacing to restore breathing and for dynamic graciloplasty to achieve fecal continence. The 3 different stimulation techniques currently used for electrophrenic respiration (EPR) all apply high frequency powered implants. It was our goal to make these stimulation methods applicable for EPR by a battery-powered nerve stimulator that would maximize the patient's freedom of movement. Additionally, the system should allow the implementation of multichannel techniques and alternating stimulation of 2 skeletal muscles as a further improvement in graciloplasty. Generally, the developed implantable nerve stimulator can be used for simultaneous and alternating activation of 2 skeletal muscles. Stimulation of the motor nerve is achieved by either single channel or multichannel methods. Carousel stimulation and sequential stimulation can be used for graciloplasty as well as for EPR. For EPR we calculated an operating time of the implant battery of 4.1 years based on the clinically used stimulation parameters with carousel stimulation. The multichannel pulse generator is hermetically sealed in a titanium case sized 65 x 17 mm (diameter x height) and weighs 88 g.


Asunto(s)
Suministros de Energía Eléctrica , Terapia por Estimulación Eléctrica/instrumentación , Músculo Esquelético/fisiología , Prótesis e Implantes , Diafragma/inervación , Diafragma/fisiología , Electrónica Médica/instrumentación , Diseño de Equipo , Incontinencia Fecal/cirugía , Humanos , Neuronas Motoras/fisiología , Contracción Muscular/fisiología , Músculo Esquelético/inervación , Músculo Esquelético/trasplante , Nervio Frénico/fisiología , Respiración , Factores de Tiempo , Titanio
18.
Artif Organs ; 23(5): 428-31, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10378935

RESUMEN

Long-term flights in microgravity cause atrophy and morphological changes of skeletal muscles. Training with mechanical devices is insufficient regarding the required time to exercise and space for devices. The objective of this project is to develop a passive training method based on functional electrostimulation (FES) to preserve muscle mass and fiber composition with minimal impairment to the cosmonaut. For a pilot experiment on the MIR space station, a suitable 8 channel FES device was developed. It consists of electrode trousers that carry surface electrodes and cables, 2 interconnected 4 channel stimulators, and a laptop personal computer (PC) for stimulator programming and processing compliance data. An automatic extensive training of 4 muscle groups of the lower extremities is performed for 6 h/day, with 1 s on and 2 s off tetanic contractions at 20-30% of maximum tetanic muscle force. The synchronous activation of antagonists of the thigh and lower leg prevents uncoordinated movements.


Asunto(s)
Reposo en Cama/efectos adversos , Terapia por Estimulación Eléctrica , Atrofia Muscular/prevención & control , Ingravidez/efectos adversos , Vestuario , Terapia por Estimulación Eléctrica/instrumentación , Terapia por Estimulación Eléctrica/métodos , Electrodos , Diseño de Equipo , Humanos , Pierna/fisiología , Microcomputadores , Contracción Muscular/fisiología , Fibras Musculares Esqueléticas/patología , Fibras Musculares Esqueléticas/fisiología , Músculo Esquelético/patología , Músculo Esquelético/fisiología , Proyectos Piloto , Programas Informáticos , Nave Espacial , Muslo/fisiología
19.
Artif Organs ; 23(5): 466-9, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10378945

RESUMEN

Spinal cord lesions at level C5 to C6 lead to loss of hand functions and lesions at C4 to additional deficits of arm functionality. The presented dual channel surface stimulator with dual channel electromyogram (EMG) measurement was developed to investigate control strategies for an EMG-controlled implantable stimulation system and serves in addition as a therapy device for patients with partial innervation but weak muscle force. Four different control strategies for stimulation amplitude are available. The amplitude can be preset manually or can follow the preprocessed EMG signals proportionally. The shoulder control program allows proportional control of both stimulation channels with one EMG channel while the second EMG channel serves as the channel selector. Finally, a special feedback training program triggers a stimulation burst when EMG activity is detected. During a 2 year patient study, 18 patients from 2 hospitals and 1 rehabilitation center performed the feedback training. Almost all patients obtained an improvement of functionality. Apart from muscle strengthening, the feedback effect led to an improvement of proprioception and supported relearning of motions. For the documentation of the training status, functional muscle test (British Medical Research Council) and measurements of power, angle, torque, muscle fatigue, and EMG were performed. Obviously, EMG triggered stimulation provides several advantages compared to conventional passive electrical stimulation.


Asunto(s)
Brazo , Terapia por Estimulación Eléctrica/métodos , Electromiografía , Parálisis/rehabilitación , Plexo Braquial/lesiones , Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Retroalimentación , Hemiplejía/rehabilitación , Humanos , Movimiento/fisiología , Contracción Muscular/fisiología , Fatiga Muscular/fisiología , Debilidad Muscular/terapia , Músculo Esquelético/inervación , Músculo Esquelético/fisiopatología , Parálisis/etiología , Propiocepción/fisiología , Hombro/fisiología , Enfermedades de la Médula Espinal/complicaciones , Torque
20.
Artif Organs ; 23(4): 352-9, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10226700

RESUMEN

Different methods are used, clinically and experimentally, to assist severely impaired heart function by means of skeletal muscle. The efficiency of these methods is restricted by skeletal muscle losing strength after transpositioning and during conditioning and not being sufficiently resistant to fatigue. This is mainly due to the nonphysiological activation of the nerves by electrical stimulation. We have developed a battery operated, ECG triggered multichannel implant that is capable of implementing various advanced stimulation techniques. The stimulator can activate 2 skeletal muscles via the motor nerves. It allows for application of multichannel stimulation methods, i.e., carousel stimulation and sequential stimulation, as well as the programming of optimized pulse trains. Synchronization delay and burst duration can be automatically and dynamically adapted to the heart rate. The multichannel stimulator is hermetically sealed in a titanium case. Its calculated life span on the basis of the integrated battery is 3-5 years, depending on the programmed stimulation parameters. The implant dimensions are 65 x 17 mm (diameter x height), and it weighs 93 g. The implant has been tested in vitro as well as in vivo.


Asunto(s)
Cardiomioplastia , Estimulación Eléctrica/instrumentación , Músculo Esquelético/inervación , Animales , Electrocardiografía , Diseño de Equipo , Implantes Experimentales , Ovinos
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