RESUMEN
BACKGROUND: In postherpetic neuralgia (PHN), dorsal root ganglia neurons are damaged. According to the proposed models, PHN pain might be associated with nociceptive deafferentation, and peripheral (heat hyperalgesia) or central sensitization (allodynia). METHODS: In 36 PHN patients, afferent nerve fibre function was characterized using quantitative sensory testing and histamine-induced flare analysis. Psychological factors were evaluated with the Hospital Anxiety and Depression Scale (HADS), disease-related quality of life (QoL) with SF-36 and pain with the McGill questionnaire [pain rating index (PRI)]. The patients were also divided into subgroups according to the presence or absence of brush-evoked allodynia as a sign of central sensitization. RESULTS: For all patients, warm, cold and mechanical detection was impaired (p < 0.001 each) and the size of the histamine flare was diminished on the affected side (p < 0.05); pain thresholds with the exception of brush-evoked allodynia (p < 0.05) were unaltered. Correlation analysis revealed allodynia, anxiety, depression, QoL and age as relevant factors associated with pain severity (PRI). Allodynia was present in 23 patients (64%). In these patients, heat pain perception was preserved; the histamine flare was larger; the pinprick pain was increased as were McGill PRI sensory subscore, actual pain rating and almost significantly pain (McGill PRI) over the last 4 weeks. CONCLUSIONS: PHN is associated with damage of afferent fibres. Central sensitization (i.e., allodynia) might contribute to PHN pain. There was a striking association between anxiety, depression and age, and the magnitude of PHN pain.
Asunto(s)
Trastornos de Ansiedad/complicaciones , Sensibilización del Sistema Nervioso Central/fisiología , Neuralgia Posherpética/complicaciones , Dolor/etiología , Adulto , Anciano , Ansiedad/fisiopatología , Potenciales Evocados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuralgia Posherpética/terapia , Dolor/fisiopatología , Umbral del Dolor/fisiología , Calidad de VidaAsunto(s)
Antígenos CD19/inmunología , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda/inmunología , Leucemia Mieloide Aguda/cirugía , Síndromes Mielodisplásicos/inmunología , Síndromes Mielodisplásicos/cirugía , Neprilisina/inmunología , Células Precursoras de Linfocitos B/inmunología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Permanent secondary stability of the uncemented femoral stem of hip prostheses can only be achieved once primary rotational and axial stability has been ensured. Rotational stability means that the stem is resistant to the articular forces that induce rotation around the implant's longitudinal axis. The 10-year survival rates of two uncemented conical shaped stems with decisively different proximal shapes were significantly different (Schenker SK 63.9%, Zweymüller SL 97.0%). The shapes were analyzed biomechanically by testing rotational stability in a silicone model. A reduction in the mediolateral height of the metaphyseal part by one-third led to a 20% smaller angle of ascent (P < 0.01), which indicated lower resistance. The proximally broader (mediolateral) prosthesis therefore proved to have better rotational stability. The study confirms that aseptic stem loosening is attributable to the design of the proximal part of the prosthesis.
Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Prótesis de Cadera/normas , Ensayo de Materiales/métodos , Fenómenos Biomecánicos , Cementos para Huesos , Análisis de Falla de Equipo , Estudios de Seguimiento , Prótesis de Cadera/efectos adversos , Humanos , Modelos de Riesgos Proporcionales , Diseño de Prótesis , Falla de Prótesis , Rango del Movimiento Articular , Reoperación , Rotación , Análisis de Supervivencia , Torque , Anomalía Torsional/fisiopatología , Resultado del TratamientoRESUMEN
The Thermoelastic Stress Analysis (THESA) is a widely used procedure in motorcar- and airplane engineering. This study investigated the reliability of THESA for stress analysis of human bone. A human femur was cyclic stressed and the resulting stress pattern was scanned from the surface of the bone by means of the thermoelastic stress measuring instrument SPATE 9000. To proof whether the scan of SPATE 9000 is equivalent to the stress distribution of human femur surface, strain gauges are used to control the results at two different regions of the femur diaphysis under equal but static conditions. It could be shown, that both measuring methods lead to corresponding results of stress pattern on human femur surface.