European Pain Federation position paper on appropriate opioid use in chronic pain management.

Poorly controlled pain is a global public health issue. The personal, familial and societal costs are immeasurable. Only a minority of European patients have access to a comprehensive specialist pain clinic. More commonly the responsibility for chronic pain management and initiating opioid therapy rests with the primary care physician and other non-specialist opioid prescribers. There is much confusing and conflicting information available to non-specialist prescribers regarding opioid therapy and a great deal of unjustified fear is generated. Opioid therapy should only be initiated by competent clinicians as part of a multi-faceted treatment programme in circumstances where more simple measures have failed. Throughout, all patients must be kept under close clinical surveillance. As with any other medical therapy, if the treatment fails to yield the desired results and/or the patient is additionally burdened by an unacceptable level of adverse effects, the overall management strategy must be reviewed and revised. No responsible clinician will wish to pursue a failed treatment strategy or persist with an ineffective and burdensome treatment. In a considered attempt to empower and inform non-specialist opioid prescribers, EFIC convened a European group of experts, drawn from a diverse range of basic science and relevant clinical disciplines, to prepare a position paper on appropriate opioid use in chronic pain. The expert panel reviewed the available literature and harnessed the experience of many years of clinical practice to produce these series of recommendations. Its success will be judged on the extent to which it contributes to an improved pain management experience for chronic pain patients across Europe. SIGNIFICANCE: This position paper provides expert recommendations for primary care physicians and other non- specialist healthcare professionals in Europe, particularly those who do not have ready access to specialists in pain medicine, on the safe and appropriate use of opioid medications as part of a multi-faceted approach to pain management, in properly selected and supervised patients.

Neuraxial analgesia in a pregnant woman with Fowler's syndrome and sacral neuromodulation.

We report the anesthetic management of a 16-year-old woman with Fowler's syndrome who became pregnant three years after sacral neuromodulation was initiated for treatment of the condition. Multidisciplinary consensus was to switch off the neurostimulator during pregnancy, and attempt vaginal delivery with a neuraxial block. When the patient was admitted for labor, an epidural catheter was placed successfully. The patient had a normal vaginal delivery. Sacral neuromodulation was restarted uneventfully in the early puerperium and the Fowler's syndrome remains well controlled. The baby continues to develop normally three years after delivery.

[Assessment of the impact of pain on work productivity: validation of the Spanish WPAI:Pain questionnaire]. / Valoración de la repercusión del dolor sobre la productividad laboral: validación del cuestionario WPAI:Pain.

BACKGROUND: Health measuring instruments are essential in daily clinical practice. However, a validation process is needed in order to certify the validity and reliability of it. The aim of our study is to validate a questionnaire to assess the consequences of pain in work productivity. METHODS: Based on the Work Productivity and Activity Impairment Questionnaire ­ General Health we have created a modified version called WPAI:Pain in order to be able to measure the consequences of pain in work productivity. The study was conducted following the usual guidelines of test validation, omitting face validity as WPAI:Pain is a modification of an existing questionnaire. Validity and reliability were calculated. RESULTS: A total of 577 questionnaires were obtained in 2 spanish university hospitals. The questionnaire's discriminating power was verified by Mann-Whitney test. Reliability tests were realized, Cronbach's alpha was 0.896 and Guttman split-half was 0.921. Stability was evaluated with a test-retest which was significant. Construct validity was established by Pearson correlation comparing the results of the questionnaire with the pain visual analog scale, which was statistically significant for all values. CONCLUSIONS: The WPAI:Pain questionnaire is a valid instrument for measuring the consequences of pain in work productivity.It is currently the only one validated in Spanish.Major studies are needed in order to establish its universal validity.

Inter- and intra-patient variability in breakthrough pain episodes of opioid-treated patients with underlying chronic pain. An observational, prospective and multicenter study / Variabilidad inter- e intra-individual en pacientes con dolor irruptor tratados con opioides. Estudio observacional, prospectivo y multicéntrico

Objective: Since, to date, there are few epidemiological data assessing the diversity in the characteristics of breakthrough pain episodes, the present study was performed to assess the intra-individual variability in the episodes of breakthrough pain in patients with underlying chronic pain controlled with opioids. Methods: An observational, prospective and multicenter study (CADI study) was conducted in the context of the routine clinical practice of Spanish pain specialists recruiting opioidtreated patients with underlying chronic pain. Data were recorded in three visits (baseline, at 7 and 28 days post-inclusion) and by the patient on a patient´s diary card, specifically designed to characterise the first 8 breakthrough pain episodes (type, intensity –using 100 mm Visual Analog Scale– and duration of pain), to assess the intra-individual and inter-individual variability in the intensity, duration and typology of episodes of breakthrough pain. Results: 50 opioid-treated patients were recruited (23 with oncologic pain and 27 with non oncologic pain, mean age of 61.1 years, 62 % females). For all three parameters, inter-patient variability was higher than intra-patient variability throughout the episodes. Nevertheless, we found intra-patient variability in maximum pain intensity, pain intensity at the end of the episode, pain relief and duration of the episode. Conclusions: This is the first study to quantify the intrapatient variability of breakthrough pain. The results show a great variability in terms of intensity and duration of the episode and its typology. Although inter-patient variability is higher, the intra-patient variability is important enough to be taken into account in optimizing the approach and treatment selection (AU)

Objetivos: Debido a los pocos datos epidemiológicos existentes que evalúen la diversidad de las características de los episodios de dolor irruptivo, se realizó el presente estudio, cuyo principal objetivo fue evaluar la variabilidad intraindividual de las crisis de dolor irruptivo en pacientes con dolor crónico controlado con opioides. Métodos: Este estudio observacional, prospectivo y multicéntrico (estudio CADI) se llevó a cabo en el contexto de la práctica clínica habitual, en Unidades del Dolor de España, con la participación de pacientes tratados con opioides para el dolor crónico. Los datos fueron registrados en tres visitas (basal, a los 7 y 28 días después de la inclusión) y por el propio paciente, en un Diario del Paciente, específicamente diseñado para caracterizar los primeros 8 episodios de dolor irruptivo (tipo, intensidad −utilizando la Escala Analógica Visual (EVA)− y duración del dolor) con el objetivo de evaluar la variabilidad intraindividual e interindividual en la intensidad, duración y tipología de los episodios de dolor irruptivo. Resultados: Se reclutaron 50 pacientes, 23 con dolor oncológico y 27 con el dolor no oncológico (edad media de 61,1 años; 62 % de mujeres). Aunque para los tres parámetros medidos, la variabilidad entre pacientes fue mayor que la variabilidad intrapaciente, la variabilidad intraindividual fue significativa en la evaluación de la máxima intensidad del dolor, la intensidad del dolor al final del episodio, el alivio del dolor y la duración del episodio de dolor irruptivo. Conclusiones: Este es el primer estudio que cuantifica la variabilidad intraindividual del dolor irruptivo. Los resultados muestran una gran variabilidad en cuanto a la intensidad y la duración del episodio y su tipología. Aunque la variabilidad entre pacientes es mayor, la variabilidad intrapaciente es lo suficientemente importante como para ser tenida en cuenta para la mejor aproximación y selección del tratamiento (AU)

Calidad de vida y satisfacción del paciente anciano no oncológico con dolor irruptivo tratado con fentanilo sublingual / Quality of life and satisfaction in the elderly not cancer patient with breakthrough pain treated with sublingual fentanyl

Introducción: La prevalencia del dolor irruptivo (DI) es > 55 % en los pacientes no oncológicos y cercana al 70 % en pacientes con dolor crónico. El DI deteriora el estado funcional y emocional de los pacientes, lo cual se traduce en una menor calidad de vida. Se ha descrito que un 50 % de la población oncológica anciana podría padecerlo, pero en ancianos no oncológicos los datos disponibles sobre el tratamiento del DI son limitados. Objetivos: El objetivo primario de este estudio fue valorar la calidad de vida y la satisfacción del paciente anciano no on cológico con DI tratado con fentanilo sublingual. Los objetivos secundarios fueron evaluar el cambio en la intensidad del dolor, el número de episodios de DI y el tiempo de respuesta al tratamiento con fentanilo sublingual, y describir su perfil de seguridad. Material y métodos: Estudio retrospectivo multicéntrico realizado en 78 pacientes con un periodo de recogida de datos de un mes. Se eligió a pacientes > 70 años, con DI (EVA ≥ 6) y tratamiento de base con opioides, a los cuales se les hubiera prescrito citrato de fentanilo sublingual para el tratamiento del DI. Se incluyeron datos basales (control 0) y de las visitas/ controles telefónicos a los 3, 15 y 30 días (controles 1, 2 y 3, respectivamente). Resultados: Al inicio del estudio, el valor medio de EVA fue de 7,52 (DE 0,90) y la afectación media en las actividades cotidianas en el cuestionario CBD fue de 6,7/10 (DE 1,21). Al finalizar el estudio los pacientes tuvieron una afectación de 4,36/10 en sus actividades diarias a causa del dolor (p < 0,0001). El promedio de los ítems de intensidad del dolor (CBD) se redujo 2,38 puntos vs. basal (p < 0,0001). La puntuación media en las dimensiones de salud física y salud mental del cuestionario SF-12 subió 2,46 y 9,27 puntos, respectivamente, vs. basal, de forma significativa (p = 0,0051 y p < 0,0001, respectivamente). El 75,32 % de los pacientes y el 92,21 % de los investigadores calificaron el tratamiento como 'bueno' o 'excelente'. En el control 3, los pacientes tuvieron de media cerca de 17 episodios mensuales menos de DI vs. basal, reducción que fue significativa. La incidencia de pacientes con una duración del episodio de DI < 30 min aumentó de forma significativa vs. basal (80,26 vs. 46,16 %; p < 0,05). El porcentaje de pacientes que tomaban medicación coadyuvante se redujo de forma significativa a lo largo del estudio (64,94 % control 3, vs. 75,32 % basal). Conclusiones: Los resultados de este estudio demuestran que el tratamiento con fentanilo sublingual puede contribuir a mejorar la calidad de vida del paciente anciano con DI y dolor crónico no oncológico, al mejorar significativamente todos los ítems relativos a la interferencia con las actividades diarias (cuestionario CBD), así como los de salud física y mental del cuestionario SF-12. El grado de satisfacción fue muy alto en pacientes e investigadores. Desde el primer control se produjo un descenso significativo vs. basal en la escala EVA, en el número medio de episodios de DI y en el tiempo de respuesta al tratamiento (AU)

Introduction: The prevalence of breakthrough pain (BTP) is > 55 % in non-cancer patients and around 70 % in patients with chronic pain. BTP impairs functional and emotional status of patients, resulting in a lower quality of life (QoL). It has been reported that 50 % of elderly cancer population could suffer BTP, but data on the treatment of BTP in the elderly non-cancer population are scarce. Objectives: The primary objective of this study was to assess the QoL and satisfaction of elderly non-cancer patients with BTP treated with sublingual fentanyl citrate. Secondary objectives were to evaluate the variation of pain intensity, the number of BTP episodes and the time of response to treatment, and describe the safety profile of sublingual fentanyl citrate. Methods: This was a retrospective multicenter study (n = 78) with a data collection period of 1 month. Eligible patients were > 70 years, with BTP (VAS ≥ 6) and opioids as basal treatment, who were prescribed sublingual fentanyl citrate for the treatment of BTP. Baseline data (control 0) and visits / phone controls at 3, 15 and 30 days (controls 1, 2 and 3, respectively) were performed. Results: At baseline, the mean VAS was 7.52 (SD 0.90) and the mean impairment of daily activities (CBD questionnaire) was 6.7/10 (SD 1.21). At the end of the study this value was 4.36/10 (p < 0.0001). The average score of the pain intensity category (CBD) was 2.38 lower vs. baseline (p < 0.0001). The average score on the dimensions of physical health and mental health of the SF-12 questionnaire rose significantly 2.46 and 9.27 points, respectively, vs. baseline (p = 0.0051 and p < 0.0001, respectively). The treatment was considered 'good' or 'excellent' by 75.32 % of patients and 92.21 % of researchers. At the end of the study patients had nearly 17 monthly BTP episodes less vs. baseline on average; this reduction was significant. The incidence of patients with BTP episode duration < 30 min significantly increased vs. baseline (80.26 vs. 46.16 %, p < 0.05). The percentage of patients taking adjuvant medication was reduced significantly during the study (64.94 vs. 75.32 % at baseline). Conclusions: The results of this study demonstrate that treatment with sublingual fentanyl citrate can help improve the QoL of elderly patients with chronic non-cancer pain and BTP, as it significantly improved all items regarding interference with daily activities (questionnaire CBD) as well as physical and mental health items of the SF-12 questionnaire. The degree of satisfaction was very high in both patients and researchers. Since the beginning of treatment there was a significant decrease vs. baseline not only in VAS scores, but in the average number of BTP episodes and in the time of response to treatment (AU)

Real Decreto de prescripción y dispensación de estupefacientes / No disponible

No disponible

Neuralgia del trigémino: radiofrecuencia ganglio de Gasser / No disponible

No disponible

Situación actual de la radiofrecuencia en España / No disponible

Introducción: el tratamiento de procesos dolorosos agudos y crónicos puede ser todo un reto para el personal médico. Se han desarrollado numerosas técnicas farmacológicas e invasivas para tratar el dolor. Dentro de estas últimas se sitúan las técnicas de radiofrecuencia. La radiofrecuencia (RF) es una técnica mínimamente invasiva cuyo uso se está implementando en las unidades del dolor, neurocirugía y traumatología de toda Europa. Objetivos: valorar la situación de la radiofrecuencia en el estado español. Material y métodos: se realizó una encuesta remitida a las unidades del dolor de España a lo largo de 2010. Población diana: Unidades del Dolor incluidas en el directorio de la Sociedad Española del Dolor (SED). Resultados: aunque de las 119 encuestas enviadas se recogieron tan solo 59 (49,57%), se sobreentiende que las 60 (50,43%) restantes o no están interesadas por contestar la encuesta o no están realizando técnicas de RF. Teniendo en cuenta este posible sesgo de selección, se puede concluir que un 39,49% de las Unidades del Dolor del directorio de la SED realizan técnicas de RF. La media de pacientes sometidos a procedimientos de RF es de 23 al mes, con un máximo de 60 y un mínimo de 2. Las técnicas más frecuentemente realizadas son RF de Facetas Lumbares y RF de Nervios Periféricos. El 85% de los centros que realizan RF han recibido formación específica en estas técnicas. El 95% de los centros que realizan RF estarían interesados en recibir o mejorar esta formación (AU)

Introduction: the use of minimally invasive techniques to treat patients with pain is a common practice in the field of medicine. Multiple percutaneous and minimally invasive techniques to treat moderate to severe pain have been introduced recently. Radiofrequency is one of these minimally invasive techniques that has grown substantially over the past decade in pain units, orthopaedic surgery units, radiology units and neurosurgery units. Objective: to evaluate the situation of radiofrequency procedures in Spain. Material and methods: a national survey was sent to the pain units in Spain through 2010. Results: 119 surveys were sent. Only 59 were completed. 60 didn’t answer the survey. Admitting this conclusion can be a bias, at least 39% of the pain units in Spain are performing radiofrequency techniques. The mean number of procedures is 23 per month, with a maximum of 60 and a minimum of 2. The most frequently performed techniques are lumbar facet denervation and peripheral nerve pulsed radiofrequency. 85% of the pain units that perform Radiofrequency procedures had received specific training. 95% of the pain units are interested in receiving specific training for radiofrequency procedures (AU)

Estimulación de nervio periférico en el tratamiento de diferentes tipo de cefaleas / Peripheral nerve stimulation in the treatment of various types of headache

Introducción. La cefalea constituye una enfermedad con gran impacto en la calidad de vida y la economía de los países industriales. Una de las teorías fisiopatológicas se encuentra la activación de las fibras aferentes cervicales de los nervios C2-C3. La neuroestimulación periférica aferente de C2-C3, que se provoca en la estimulación del nervio occipital, parece aliviar la cefalea a través de las conexiones trigeminocervicales, y ser una de las causas principales de su eficacia. Material y métodos. Estudio multicéntrico retrospectivo entre abril 2005 y mayo 2009. Se incluyó a los pacientes con cefalea crónica mayor que fueron tratados con neuroestimulación. En todos los pacientes se valoró el tipo de cefalea, el grado de dolor mediante una escala numérica simple, tratamiento médico y episodios de cefalea. Se analizó el porcentaje de test negativos. En los portadores del generador definitivo se valoró la eficacia de la técnica mediante el análisis de la escala numérica simple y el análisis del porcentaje de mejoría subjetiva de los pacientes al mes, 3 meses, 6 meses y 12 meses. Se analizó el grado de cobertura, la satisfacción, la disminución de los episodios y la medicación y las complicaciones. Resultados. Se incluyeron 31 pacientes. El resultado del test fue positivo en el 87%. Existió una disminución significativa (p < 0,001) del dolor desde el momento basal con una mejoría mayor del 50% sostenido del 85,2% y un descenso en la puntuación de la escala numérica simple > 2 puntos en un 96,3% de los casos. Todos los pacientes estaban satisfechos durante el estudio. El 56% de la muestra no tuvo episodios de cefaleas tras el año de estudio y el 47% dejo de tomar medicación. La complicación más frecuente fue la migración del electrodo (AU)

Background and objective. Headache has a great impact on patients quality of life and in industrialized countries there is economic impact as well. One of the pathophysiologic theories to explain headache is activation of afferent C2-C3 nerve fibers. Afferent peripheral nerve stimulation by occipital nerve provocation at C2-C3 seems to alleviate headache by acting on the trigeminocervical complex, which would largely explain the effectiveness of this modality. The aim of this study was to describe peripheral nerve stimulation as an alternative therapy in patients who do not respond to other headache treatments. Material and methods. Multicenter retrospective study between April 2005 and May 2009, analyzing cases of patients treated with nerve stimulation for severe chronic headache. In all patients the medical history included type of headache, intensity of pain on a numerical scale, medical treatment used, and number of headache episodes. We recorded the percentage of patients with negative tests. Patients implanted with a generator assessed effectiveness on the numerical scale; we analyzed the percentage of perceived improvement at 1, 3, 6, and 12 months. We also analyzed the extent of coverage provided by the electrodes, patient satisfaction, reduction in the number of episodes and medication, and complications. Results. Of 31 patients, 87% had positive results, with a significant decrease in pain from baseline (P <. 001); 85.2% reported sustained improvement of >50%, and 96.3% reported a decrease of > 2 points on the pain scale. All patients expressed satisfaction during the period of follow-up. Fifty-six percent had no headaches after a year and 47% had stopped taking medication. The most frequent complication was electrode migration (AU)

Radiofrecuencia de facetas lumbares y cervicales / No disponible

No disponible

Radiofrecuencia pulsada del ganglio dorsal de las raíces lumbares / No disponible

No disponible

[Peripheral nerve stimulation in the treatment of various types of headache]. / Estimulación de nervio periférico en el tratamiento de diferentes tipo de cefaleas.

BACKGROUND AND OBJECTIVE: Headache has a great impact on patients' quality of life and in industrialized countries there is economic impact as well. One of the pathophysiologic theories to explain headache is activation of afferent C2-C3 nerve fibers. Afferent peripheral nerve stimulation by occipital nerve provocation at C2-C3 seems to alleviate headache by acting on the trigeminocervical complex, which would largely explain the effectiveness of this modality. The aim of this study was to describe peripheral nerve stimulation as an alternative therapy in patients who do not respond to other headache treatments. MATERIAL AND METHODS: Multicenter retrospective study between April 2005 and May 2009, analyzing cases of patients treated with nerve stimulation for severe chronic headache. In all patients the medical history included type of headache, intensity of pain on a numerical scale, medical treatment used, and number of headache episodes. We recorded the percentage of patients with negative tests. Patients implanted with a generator assessed effectiveness on the numerical scale; we analyzed the percentage of perceived improvement at 1, 3, 6, and 12 months. We also analyzed the extent of coverage provided by the electrodes, patient satisfaction, reduction in the number of episodes and medication, and complications. RESULTS: Of 31 patients, 87% had positive results, with a significant decrease in pain from baseline (P < .001); 85.2% reported sustained improvement of > 50%, and 96.3% reported a decrease of > 2 points on the pain scale. All patients expressed satisfaction during the period of follow-up. Fifty-six percent had no headaches after a year and 47% had stopped taking medication. The most frequent complication was electrode migration.

Recomendaciones para el manejo de la vía aérea difícil mediante dispositivos extraglóticos en el paciente adulto sometido a cirugía ambulatoria / No disponible

No disponible

[Neuromuscular blockade monitoring. Part 1]. / Monitorización del bloqueo neuromuscular. 1a parte.

Many recent studies have underlined the importance of quantitative neuromuscular monitoring and the high incidence of residual block in clinical practice in spite of the use of nondepolarizing neuromuscular blockers of intermediate duration. Neuromuscular monitoring facilitates the tailoring of the muscular paralysis and appropriate patient recovery at the end of surgery. Monitoring also controls or prevents residual block and serves to guide the use of reversing agents. This review describes the physiology of neuromuscular junctions as well as the principles and patterns of nerve stimulation and clinical monitoring. In addition to drawing on their own experience, the authors have reviewed the literature available through evidence-based indexes and other databases up to December 2008. Most references found were case series and reviews. Quantitative monitoring is an evidence-based practice that should be applied in all situations in which a neuromuscular block is established.

Monitorización del bloqueo neuromuscular. 1ª parte / Neuromuscular blockade monitoring. Part 1

En recientes publicaciones han aparecido múltiplesestudios sobre la importancia de la monitorizaciónneuromuscular cuantitativa y la alta incidencia delbloqueo residual en la práctica clínica, a pesar de lautilización de fármacos bloqueantes neuromusculares nodespolarizantes de duración intermedia. El uso de lamonitorización neuromuscular permite realizar unaparálisis muscular a medida y recuperar al pacienteadecuadamente al final de la cirugía, evitando ocontrolando el bloqueo residual, y sirviendo de guía parala utilización de los reversores de dicho bloqueo. Estarevisión describe específicamente la fisiología de la uniónneuromuscular, principios, patrones de estimulación ypráctica de la monitorización neuromuscular en laclínica. Además de la propia experiencia de los autoresen el uso de la monitorización neuromuscular, se harealizado una revisión de la literatura médica existentehasta diciembre de 2008 mediante una búsqueda en lasbases de datos de medicina basada en la evidencia, y enlas bases de datos bibliográficas. La mayor parte de lasreferencias encontradas son series de casos y revisiones.La monitorización cuantitativa es una práctica basadaen la evidencia que debe consecuentemente utilizarsesiempre que se utiliza un bloqueo neuromuscular(AU)

Many recent studies have underlined the importanceof quantitative neuromuscular monitoring and the highincidence of residual block in clinical practice in spite ofthe use of nondepolarizing neuromuscular blockers ofintermediate duration. Neuromuscular monitoringfacilitates the tailoring of the muscular paralysis andappropriate patient recovery at the end of surgery.Monitoring also controls or prevents residual block andserves to guide the use of reversing agents. This reviewdescribes the physiology of neuromuscular junctions aswell as the principles and patterns of nerve stimulationand clinical monitoring. In addition to drawing on theirown experience, the authors have reviewed the literatureavailable through evidence-based indexes and otherdatabases up to December 2008. Most references foundwere case series and reviews. Quantitative monitoring isan evidence-based practice that should be applied in allsituations in which a neuromuscular block is established(AU)

Monitorización del bloqueo neuromuscular. 2ª parte / No disponible

No disponible

[Effect of posture on spinal cord stimulation in patients with chronic pain syndromes: analysis of energy requirements in different patient postures]. / Efecto de la postura en la estimulación medular en pacientes con síndromes de dolor crónico. Análisis del gasto de energía dependiendo de la postura del paciente.

BACKGROUND AND OBJECTIVE: Patients being treated with spinal cord stimulation for chronic pain complain of variable paresthesias, particularly in relation to changes in posture. Such changes affect the great majority of patients with implantable pulse generators, requiring them to use the external programmer for avoidance of painful paresthesias or even to disconnect the generator, leading to loss of pain relief. The aim of this study was to determine the relationship between the pulse charge needed for stimulation and the patient's different postures. MATERIAL AND METHODS: Observational study of 70 patients treated with spinal cord stimulation in the following postures and situations: decubitus position, standing, seated, and walking. With the patients standing, we analyzed the thresholds of perception, pain, and pain relief, as well as the therapeutic range. Studies were performed in all patients. Later, data were analyzed by anatomical positioning of the stimulator (cervical, thoracic, sacral, occipital, or subcutaneous). RESULTS: In the analysis of the therapeutic range in the overall group we identified statistically significant differences between decubitus and standing positions and between decubitus position and walking. At the level of the thoracic spine differences were identified between all positions except between standing and walking and between seated and decubitus positions. At the level of the cervical spine, no significant differences were detected. Analysis of the pulse charge showed a significant difference in the decubitus position, in which less charge was needed to achieve satisfactory stimulation. When electrodes implanted at the cervical and thoracic levels were compared, differences were found between standing and seated positions (P=.04) but none between decubitus position or walking and the other positions. CONCLUSION: Stimulation systems are not currently designed to adapt to changes in distance between the electrodes and nerve fibers. Improvements are required in this respect.