Effect of muscle strengthening on perceived pain and static knee angles in young subjects with patellofemoral pain syndrome

The purpose of this pilot study was to determine the effects of strength training of the knee muscles on perceived pain and static knee angles in young subjects with patellofemoral pain syndrome (PFPS). Ten pa-tients, 100% female (mean age, 18.2\ub13.8 years), with unilateral PFPS (anterior knee pain for at least 3 months), received muscle strengthen-ing of the hip and knee (10 sessions over a period of 3 weeks). The out-come measures were perceived pain (visual analogue scale, VAS) and static knee angles (knee rotation measurer). All measures were collect-ed at pre-, postintervention, and at 1-month follow-up (VAS). Muscle strengthening reduced perceived pain after intervention in 90.8% in subjects and this result was maintained at 1-month follow-up (all, P=0.001). Regarding changes in static knee angles, no significant im-provements were found in internal and external rotation; valgus and varus; flexion and recurvatum (all, P>0.05). There was no significant difference between the symptomatic and healthy sides (all, P>0.05). Analyses of the correlation coefficients indicated no significant associ-ations between changes in perceived pain and static knee angles. The current study found that muscle strengthening addressed to the symp-tomatic knee reduced pain; however, perceived pain was not associat-ed with static knee angles in young subjects with unilateral PFPS

An increased response to experimental muscle pain is related to psychological status in women with chronic non-traumatic neck-shoulder pain

<p>Abstract</p> <p>Background</p> <p>Neck-shoulder pain conditions, e.g., chronic trapezius myalgia, have been associated with sensory disturbances such as increased sensitivity to experimentally induced pain. This study investigated pain sensitivity in terms of bilateral pressure pain thresholds over the trapezius and tibialis anterior muscles and pain responses after a unilateral hypertonic saline infusion into the right legs tibialis anterior muscle and related those parameters to intensity and area size of the clinical pain and to psychological factors (sleeping problems, depression, anxiety, catastrophizing and fear-avoidance).</p> <p>Methods</p> <p>Nineteen women with chronic non-traumatic neck-shoulder pain but without simultaneous anatomically widespread clinical pain (NSP) and 30 age-matched pain-free female control subjects (CON) participated in the study.</p> <p>Results</p> <p>NSP had lower pressure pain thresholds over the trapezius and over the tibialis anterior muscles and experienced hypertonic saline-evoked pain in the tibialis anterior muscle to be significantly more intense and locally more widespread than CON. More intense symptoms of anxiety and depression together with a higher disability level were associated with increased pain responses to experimental pain induction and a larger area size of the clinical neck-shoulder pain at its worst.</p> <p>Conclusion</p> <p>These results indicate that central mechanisms e.g., central sensitization and altered descending control, are involved in chronic neck-shoulder pain since sensory hypersensitivity was found in areas distant to the site of clinical pain. Psychological status was found to interact with the perception, intensity, duration and distribution of induced pain (hypertonic saline) together with the spreading of clinical pain. The duration and intensity of pain correlated negatively with pressure pain thresholds.</p

Influencia de la presión sobre la mucosa gingival en la medición algométrica de un punto gatillo miofascial del músculo masetero: Estudio aleatorio, cruzado, controlado

Objective: Our study sets out to determine if the pressure on the gingivae mucosa of the lower molars influences the pressure pain threshold of one of the masseter's myofascial trigger point. Material and methods: A total of 38 subjects who had orofacial pain were included in the study. The masseter's myofascial trigger point was studied. The pressure pain threshold (PPT) was measured via algometer and the intensity pain perception post-algometry measurement via Visual Analogical Scale (VAS). All study subjects were regarded either as experimental or as control group. A free-pressure measurement onto the gingivae mucosa was used in the experimental group. Meanwhile, a direct pressure measurement was used in the control group. The sequence of measurements order was carried out by means of a randomized systematical distribution. Results: There were significant statistical differences between the PPT obtained in the experimental group and those of the control group (P0.05). There was no correlation between PPT and pain intensity perception post-algometry measurement in any of the groups (r = 0.13 , P = 0.5 for the experimental group; r = 0.5 , P = 0.36). Conclusión: According to our study results, the observation shows that no pressure onto the gingivae mucosa influences in algometry measurements producing an increase in PPT valúes of the masseter's myofascial trigger point. Nevertheless, further investigation is required on the sensitivity and reliability of this protocol measurement before clinical use.Objetivo: Este trabajo valora mediante una aplicación algométrica si la presión sobre la mucosa gingival de la zona de los molares mandibulares influye sobre el umbral del dolor a la presión (UDP) de uno de los puntos gatillo miofasciales (PGMs) del músculo masetero. Material y métodos: Se estudiaron un total de 38 pacientes que presentaban dolor orofacial por PGMs a nivel del músculo masetero. Se valoro el UDP por medio de algometría y la percepción de la intensidad del dolor (PID) post-medición por medio de la Escala Visual Analógica (EVA). Todos los sujetos del estudio se utilizaron como grupo experimental y control; al grupo experimental se la aplicó una medición donde se evitaba generar presión sobre la mucosa gingival y al control una medición directa sobre PGM. El orden de aplicación de las mediciones se realizó por medio de una distribución aleatoria sistemática. Resultados: Se observaron diferencias estadísticamente significativas entre el UDP obtenido en el grupo experimental con respecto al control (P 0,05) y tampoco se apreció una correlación entre el UDP y la PID postmedición para el grupo experimental (r = -0,11, P = 0,5) ni para el caso del grupo control. (r = 0,15, P = 0,36). Conclusiones: Los resultados obtenidos demuestran que el evitar la presión sobre la mucosa gingival si influye en el valor de la medición algométrica, ya que aumenta el UDP de el PGM valorado en el músculo masetero. Sin embargo, es necesario realizar más investigaciones que puedan determinar la sensibilidad y la fiabilidad de este protocolo de medición antes de ser extrapolado a la clínica

Influencia de los cambios hormonales del ciclo menstrual en la percepción del dolor en las disfunciones temporomandibulares: Una revisión sistemática de la literatura médica

A large body of evidence suggests that temporomandibular joint disorders (TMJD) are much more prevalent in women than in men. The purpose of this systematic review was to examine whether hormone levels during the menstrual cycle infl uence TMJD when painful symptoms are present. A data extraction search strategy was performed in the Medline, Embase, Scielo and CINAHL databases from 1970 to 2008. We included cohort and case-control studies assessing several pain variables in patients with TMJD during the menstrual cycle. The quality of the studies was assessed by two independent reviewers using the Newcastle-Ottawa Scale. Four studies that met the proposed inclusion criteria were included for the qualitative analysis. The results of the studies analyzed are contradictory and consequently do not allow us to conclude that female hormone factors strongly infl uence pain perception in TMJD. Therefore, further studies are required to investigate the various female sex-related factors that could be involved in TMJD.Se dispone de una extensa literatura científica que confirma que las disfunciones temporomandibulares (DTM) presentan una mayor incidencia en mujeres. El objetivo de esta revisión es determinar si el proceso hormonal generado mediante el ciclo menstrual influye en las DTM que presentan sintomatología dolorosa. Se realizó una búsqueda de artículos científicos en las bases datos Medline, Embase, Scielo y CINAHL, entre los años 1970 y 2008. Se incluyeron estudios con diseños de cohortes y de casos y controles, donde se valoraron diversas variables del dolor durante el ciclo menstrual de personas que presentaban DTM. Dos revisores independientes valoraron la calidad de los estudios utilizando la Newcastle-Ottawa Scale. Se seleccionaron para el análisis cualitativo 4 estudios que cumplieron los criterios de inclusión propuestos. Los resultados de los estudios analizados son contradictorios, y por este motivo esta revisión no permite establecer conclusiones afirmativas en relación con el hecho que el factor hormonal femenino influye en la percepción del dolor en las DTM. Consideramos que es necesario realizar una mayor cantidad de estudios donde se investiguen los diversos aspectos del sexo femenino que puedan estar implicados en las DTM