The effect of collagen organization on tensile strength loss in anterior cruciate ligament grafts post-reconstruction surgery

Gemstone Team LEGS

Botulinum toxin type A injections for the management of muscle tightness following total hip arthroplasty: a case series.

BACKGROUND: Development of hip adductor, tensor fascia lata, and rectus femoris muscle contractures following total hip arthroplasties are quite common, with some patients failing to improve despite treatment with a variety of non-operative modalities. The purpose of the present study was to describe the use of and patient outcomes of botulinum toxin injections as an adjunctive treatment for muscle tightness following total hip arthroplasty. METHODS: Ten patients (14 hips) who had hip adductor, abductor, and/or flexor muscle contractures following total arthroplasty and had been refractory to physical therapeutic efforts were treated with injection of botulinum toxin A. Eight limbs received injections into the adductor muscle, 8 limbs received injections into the tensor fascia lata muscle, and 2 limbs received injection into the rectus femoris muscle, followed by intensive physical therapy for 6 weeks. RESULTS: At a mean final follow-up of 20 months, all 14 hips had increased range in the affected arc of motion, with a mean improvement of 23 degrees (range, 10 to 45 degrees). Additionally all hips had an improvement in hip scores, with a significant increase in mean score from 74 points (range, 57 to 91 points) prior to injection to a mean of 96 points (range, 93 to 98) at final follow-up. There were no serious treatment-related adverse events. CONCLUSION: Botulinum toxin A injections combined with intensive physical therapy may be considered as a potential treatment modality, especially in difficult cases of muscle tightness that are refractory to standard therapy.

Variaciones termométricas en la planta del pie y piernas valorada en corredores antes y después de correr 30 km

La termometría es una técnica no invasiva que permite cuantificar los cambios en la temperatura cutánea y evaluarla de forma cuantitativa. El aumento significativo de la temperatura puede indicar la existencia de patología. Se ha demostrado que la actividad muscular induce procesos de transferencia de calor entre los músculos y las capas superficiales de tejido. En este estudio queremos cuantificar los cambios de temperatura que se producen en los músculos del pie y miembro inferior tras una carrera de 30 km, para ello hemos utilizado una cámara termográfica de alta resolución. Contamos con la colaboración voluntaria de 32 sujetos sanos a los que procedimos a tomar fotografías de la planta del pie, parte anterior de la pierna, parte posterior de la pierna, parte anterior del muslo y parte posterior del muslo en dos etapas, primero antes de la carrera y segunda toma después de la carrera de 30 km, de esta manera pudimos valorar si había o no variación de temperatura en las zonas seleccionadas. Tras el análisis de los datos obtenidos encontramos significativas variaciones térmicas en Talón, cabeza primer metatarsiano, cabeza segundo metatarsiano, cabeza tercer metatarsiano, cabeza cuarto metatarsiano, cabeza quinto metatarsiano, apófisis estiloides quinto metatarsiano, arco longitudinal interno, maléolo interno, maléolo externo, peroneo lateral largo, vasto interno, vasto externo, recto femoral, tensor de la fascia lata, inserción cuádriceps, gemelo interno, tendón de Aquiles y Biceps femoral.

Conservative Interventions for mobile Pes Planus in Adults: a systematic review

Antecedentes. Pes Adulto planus (pie plano) es un problema común encontrado por muchos profesionales de la salud. A pesar de la percepción de que el pie plano puede causar dolor y deteriorar su función, la disponibilidad y el uso generalizado de diversos tratamientos, no hay consenso sobre la estrategia óptima de tratamiento. Objetivo. Evaluar la efectividad de las intervenciones conservadoras (no quirúrgicos) para pie plano en los adultos. Método. Se realizó una búsqueda sistemática de la literatura. Esto incluye: el Registro Cochrane Central de Ensayos Controlados; los Juicios CMSG Especializados Registro; una búsqueda electrónica se realizó utilizando MEDLINE (1960 a junio de 2012), EMBASE (1980 a junio de 2012), y CINAHL (1982 - junio de 2012). Revistas especializadas, listas de referencias de ensayos y artículos de revisión se realizaron búsquedas manuales. Criterios de selección: Ensayos aleatorios o cuasialeatorios de intervenciones de tratamiento para el pie plano en los adultos. Se excluyeron los ensayos que incluyeron patologías específicas como el dolor plantar del talón, las fracturas por sobrecarga de los metatarsianos, disfunción del tendón tibial posterior-, fracturas de tobillo, patologías del pie reumatoide, enfermedades neuromusculares y las complicaciones del pie diabético. Recopilación y análisis de datos: Dos autores seleccionaron de forma independiente los resultados de la búsqueda para identificar a aquellos que satisfacen los criterios de inclusión y evaluaron la calidad de los incluidos mediante una lista de control basado en la Evaluación de la Colaboración Cochrane de Riesgo. Esta herramienta se centró en el riesgo de la selección, el rendimiento, la detección, la heterogeneidad y el sesgo de notificación. Resultados. Cuatro ensayos, con 140 sujetos, cumplieron los criterios de inclusión para la revisión. Los cuatro fueron juzgados como de alto riesgo de sesgo en al menos un área, y también estaban en riesgo de sesgo incierto en al menos otra zona. Todos anotaron altamente en relación al sesgo de deserción, debido al corto seguimiento tiempos y diseños experimentales utilizados. Los datos no se agruparon debido al alto nivel de heterogeneidad identificada en las intervenciones evaluadas, los participantes seleccionados y medir los resultados. Los resultados de un estudio sugieren que después de cuatro semanas de uso ortesis puede resultar en una mejora significativa en vaivén lateral medio, y pueden resultar en una mejor, aunque no significativa, en general relacionados con la calidad de vida de los pies (Roma 2004). Un estudio (Redmond 2009) sugiere que su efecto sobre la distribución de la presión plantar en el pie puede no depender de si son personalizados o dispositivos prefabricados. Aunque este estudio se identificaron cambios significativos en algunas variables de presión plantar tanto con la costumbre y dispositivos prefabricados, otro (Esterman 2005) no encontró ningún efecto significativo de longitud ¾ ortesis prefabricadas sobre el dolor, la incidencia de lesiones, salud pie o de calidad de vida en un grupo de reclutas de la fuerza aérea. El cuarto estudio (Jung 2009) sugiere que el ejercicio de los músculos intrínsecos del pie puede mejorar el efecto de las ortesis. A pesar de estos resultados, ya que cada estudio incurrió riesgo de sesgo en al menos un área no se pueden sacar conclusiones

Second Metatarsophalangeal joint Synovitis: Update

In podiatric clinics is very common to find inflamatory process in metatarsophalangeal joint capsule , plantar plate and collateral ligaments damage, but it is not clearly recognized. Many authors hipotetized with joint instability of multiple aetiology and his concomitant evolution in different stages with own joint disease. This pathology has more incidence in second metatarsophalangeal joint than third and others and it is a common etiology of metatarsal pain. Bad biomechanics alters forefoot function and can produce overload in capsular joint, decreasing mobility and getting worse the pathology.

Development in vitro of the neuromusculature of two strigeid trematodes, Apatemon cobitidis proterorhini and Cotylurus erraticus

Confocal microscopy interfaced with cytochemical procedures has been used to monitor development of the major muscle systems and associated serotoninergic (5-HT, 5-hydroxytryptamine) and peptidergic (FaRP, FMRFamide-related peptide) innervation of the strigeid trematodes, Apatemon cobitidis proterorhini and Cotylurus erraticus during cultivation in vitro. Sexually undifferentiated metacercariae were successfully grown to ovigerous adults using tissue culture medium NCTC 135, chicken serum and egg albumen. Eggs were produced after 5 days in culture but had abnormal shells and failed to embryonate. 5-HT and FaRP (the flatworm FaRP, GYIRFamide) were localised immunocytochemically in both central and peripheral nervous systems of developing worms. During cultivation, the central serotoninergic and FaRPergic neuronal pathways of the forebody became more extensive, but retained the same basic orthogonal arrangement as found in the excysted metacercaria. Longitudinal extensor and flexor muscles of the hindbody provide support for the developing reproductive complex. The male reproductive tracts were established in advance (day 3) of those of the female system (day 4); completion of the latter was marked by the appearance of the ootype/egg chamber. The inner longitudinal muscle fibres of the female tract appeared prior to the outer and more densely arranged circular muscles. Circular fibres dominate the muscle complement of both alimentary and reproductive tracts. 5-HT- and GYIRFamide-immunoreactivities were demonstrable in the central nervous system (CNS) and subtegumental parasympathetic nervous system (PNS) throughout the culture period, but innervation of the developing reproductive structures was reactive just for 5-HT. Only at the onset of egg production was FaRP-IR observed in the reproductive system and was expressed only in the innervation of the ootype, a finding consistent with the view that FaRPs may regulate egg assembly in platyhelminths.

Gross anatomy of the muscle systems and associated innervation of Apatemon cobitidis proterorhini metacercaria (Trematoda: Strigeidea), as visualized by confocal microscopy.:Strigeidea), as visualized by confocal microscopy

The major muscle systems of the metacercaria of the strigeid trematode, Apatemon cobitidis proterorhini have been examined using phalloidin as a site-specific probe for filamentous actin. Regional differences were evident in the organization of the body wall musculature of the forebody and hindbody, the former comprising outer circular, intermediate longitudinal and inner diagonal fibres, the latter having the inner diagonal fibres replaced with an extra layer of more widely spaced circular muscle. Three orientations of muscle fibres (equatorial, meridional, radial) were discernible in the oral sucker, acetabulum and paired lappets. Large longitudinal extensor and flexor muscles project into the hindbody where they connect to the body wall or end blindly. Innervation to the muscle systems of Apatemon was examined by immunocytochemistry, using antibodies to known myoactive substances: the flatworm FMRFamide-related neuropeptide (FaRP), GYIRFamide, and the biogenic amine, 5-hydroxytryptamine (5-HT). Strong immunostaining for both peptidergic and serotoninergic components was found in the central nervous system and confocal microscopic mapping of the distribution of these neuroactive substances revealed they occupied separate neuronal pathways. In the peripheral nervous system, GYIRFamide-immunoreactivity was extensive and, in particular, associated with the innervation of all attachment structures; serotoninergic fibres, on the other hand, were localized to the oral sucker and pharynx and to regions along the anterior margins of the forebody.

The effect of simultaneous contractions of ipsilateral muscles on changes in corticospinal excitability induced by paired associative stimulation (PAS)

Consideration was given to means of increasing the reliability and muscle specificity of paired associative stimulation (PAS) by utilising the phenomenon of crossed-facilitation. Eight participants completed three separate sessions: isometric flexor contractions of the left wrist at 20% of maximum voluntary contraction (MVC) simultaneously with PAS (20s intervals; 14 min duration) delivered at the right median nerve and left primary motor cortex (MI); isometric contractions at 20% of MVC: and PAS only ( 14 min). Eight further participants completed two sessions of longer duration PAS (28 min): either alone or in conjunction with flexion contractions of the left wrist. Thirty motor potentials (MEPs) were evoked in the right flexor (rFCR) and extensor (rECR) carpi radialis muscles by magnetic stimulation of left M1 Prior to the interventions, immediately post-intervention, and 10 min post-intervention. Both 14 and 28 min of combined PAS and (left wrist flexion) contractions resulted in reliable increases in rFCR MEP amplitude, which were not present in rECR. In the PAS only conditions, 14 min of stimulation gave rise to unreliable increases in MEP amplitudes in rFCR and rECR, whereas 28 min of PAS induced small (unreliable) changes only for rFCR. These results support the conclusion that changes in the excitability of the corticospinal pathway induced by PAS interact with those associated with contraction of the muscles ipsilateral to the site of cortical stimulation. Furthermore, focal contractions applied by the opposite limb increase the extent and muscle specificity of the induced changes in excitability associated with PAS. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Role of peripheral afference during acquisition of a complex coordination task

It has long been supposed that the interference observed in certain patterns of coordination is mediated, at least in part, by peripheral afference from the moving limbs. We manipulated the level of afferent input, arising from movement of the opposite limb, during the acquisition of a complex coordination task. Participants learned to generate flexion and extension movements of the right wrist, of 75degrees amplitude, that were a quarter cycle out of phase with a 1-Hz sinusoidal visual reference signal. On separate trials, the left wrist either was at rest, or was moved passively by a torque motor through 50degrees, 75degrees or 100degrees, in synchrony with the reference signal. Five acquisition sessions were conducted on successive days. A retention session was conducted I week later. Performance was initially superior when the opposite limb was moved passively than when it was static. The amplitude and frequency of active movement were lower in the static condition than in the driven conditions and the variation in the relative phase relation across trials was greater than in the driven conditions. In addition, the variability of amplitude, frequency and the relative phase relation during each trial was greater when the opposite limb was static than when driven. Similar effects were expressed in electromyograms. The most marked and consistent differences in the accuracy and consistency of performance (defined in terms of relative phase) were between the static condition and the condition in which the left wrist was moved through 50degrees. These outcomes were exhibited most prominently during initial exposure to the task. Increases in task performance during the acquisition period, as assessed by a number of kinematic variables, were generally well described by power functions. In addition, the recruitment of extensor carpi radialis (ECR), and the degree of co-contraction of flexor carpi radialis and ECR, decreased during acquisition. Our results indicate that, in an appropriate task context, afferent feedback from the opposite limb, even when out of phase with the focal movement, may have a positive influence upon the stability of coordination.

Neural compensation for compliant loads during rhythmic movement

An experiment was performed to characterise the movement kinematics and the electromyogram (EMG) during rhythmic voluntary flexion and extension of the wrist against different compliant (elastic-viscous-inertial) loads. Three levels of each type of load, and an unloaded condition, were employed. The movements were paced at a frequency of I Hz by an auditory metronome, and visual feedback of wrist displacement in relation to a target amplitude of 100degrees was provided. Electro-myographic recordings were obtained from flexor carpi radialis (FCR) and extensor carpi radialis brevis (ECR). The movement profiles generated in the ten experimental conditions were indistinguishable, indicating that the CNS was able to compensate completely for the imposed changes in the task dynamics. When the level of viscous load was elevated, this compensation took the form of an increase in the rate of initial rise of the flexor and the extensor EMG burst. In response to increases in inertial load, the flexor and extensor EMG bursts commenced and terminated earlier in the movement cycle, and tended to be of greater duration. When the movements were performed in opposition to an elastic load, both the onset and offset of EMG activity occurred later than in the unloaded condition. There was also a net reduction in extensor burst duration with increases in elastic load, and an increase in the rate of initial rise of the extensor burst. Less pronounced alterations in the rate of initial rise of the flexor EMG burst were also observed. In all instances, increases in the magnitude of the external load led to elevations in the overall level of muscle activation. These data reveal that the elements of the central command that are modified in response to the imposition of a compliant load are contingent, not only upon the magnitude, but also upon the character of the load.

Haptic information stabilizes and destabilizes coordination dynamics

Goal-directed, coordinated movements in humans emerge from a variety of constraints that range from 'high-level' cognitive strategies based oil perception of the task to 'low-level' neuromuscular-skeletal factors such as differential contributions to coordination from flexor and extensor muscles. There has been a tendency in the literature to dichotomize these sources of constraint, favouring one or the other rather than recognizing and understanding their mutual interplay. In this experiment, subjects were required to coordinate rhythmic flexion and extension movements with an auditory metronome, the rate of which was systematically increased. When subjects started in extension on the beat of the metronome, there was a small tendency to switch to flexion at higher rates, but not vice versa. When subjects: were asked to contact a physical stop, the location of which was either coincident with or counterphase to the auditor) stimulus, two effects occurred. When haptic contact was coincident with sound, coordination was stabilized for both flexion and extension. When haptic contact was counterphase to the metronome, coordination was actually destabilized, with transitions occurring from both extension to flexion on the beat and from flexion to extension on the beat. These results reveal the complementary nature of strategic and neuromuscular factors in sensorimotor coordination. They also suggest the presence of a multimodal neural integration process-which is parametrizable by rate and context - in which intentional movement, touch and sound are bound into a single, coherent unit.

Phasic modulation of corticomotor excitability during passive movement of the upper limb: effects of movement frequency and muscle specificity

Modulations in the excitability of spinal reflex pathways during passive rhythmic movements of the lower limb have been demonstrated by a number of previous studies [4]. Less emphasis has been placed on the role of supraspinal pathways during passive movement, and on tasks involving the upper limb. In the present study, transcranial magnetic stimulation (TMS) was delivered to subjects while undergoing passive flexion-extension movements of the contralateral wrist. Motor evoked potentials (MEPs) of flexor carpi radialis (FCR) and abductor pollicus brevis (APB) muscles were recorded. Stimuli were delivered in eight phases of the movement cycle during three different frequencies of movement. Evidence of marked modulations in pathway excitability was found in the MEP amplitudes of the FCR muscle, with responses inhibited and facilitated from static values in the extension and flexion phases, respectively. The results indicated that at higher frequencies of movement there was greater modulation in pathway excitability. Paired-pulse TMS (sub-threshold conditioning) at short interstimulus intervals revealed modulations in the extent of inhibition in MEP amplitude at high movement frequencies. In the APE muscle, there was some evidence of phasic modulations of response amplitude, although the effects were less marked than those observed in FCR. It is speculated that these modulatory effects are mediated via Ia afferent pathways and arise as a consequence of the induced forearm muscle shortening and lengthening. Although the level at which this input influences the corticomotoneuronal pathway is difficult to discern, a contribution from cortical regions is suggested. (C) 2001 Published by Elsevier Science B.V.

Changes in muscle recruitment patterns during skill acquisition

The control of movement is predicated upon a system of constraints of musculoskeletal and neural origin. The focus of the present study was upon the manner in which such constraints are adapted or superseded during the acquisition of motor skill. Individuals participated in five experimental sessions, ill which they attempted to produce abduction-adduction movements of the index finger in time with an auditory metronome. During each trial, the metronome frequency was increased in eight steps from an individually determined base frequency. Electromyographic (EMC) activity was recorded from first dorsal interosseous (FDI), first volar interosseous (FVI), flexor digitorum superficialis (FDS), and extensor digitorum communis (EDC) muscles. The movements produced on the final day of acquisition more accurately matched the required profile, and exhibited greater spatial and temporal stability, than those generated during initial performance. Tn the early stages of skill acquisition, an alternating pattern of activation in FDI and FVI was maintained, even at the highest frequencies. Tn contrast, as the frequency of movement was increased, activity in FDS and EDC was either tonic or intermittent. As learning proceeded, alterations in recruitment patterns were expressed primarily in the extrinsic muscles (EDC and FDS). These changes took the form of increases in the postural role of these muscles, shifts to phasic patterns of activation, or selective disengagement of these muscles. These findings suggest that there is considerable flexibility in the composition of muscle synergies, which is exploited by individuals during the acquisition of coordination.

Brain activity during ankle proprioceptive stimulation predicts balance performance in young and older adults

Proprioceptive information from the foot/ankle provides important information regarding body sway for balance control, especially in situations where visual information is degraded or absent. Given known increases in catastrophic injury due to falls with older age, understanding the neural basis of proprioceptive processing for balance control is particularly important for older adults. In the present study, we linked neural activity in response to stimulation of key foot proprioceptors (i.e., muscle spindles) with balance ability across the lifespan. Twenty young and 20 older human adults underwent proprioceptive mapping; foot tendon vibration was compared with vibration of a nearby bone in an fMRI environment to determine regions of the brain that were active in response to muscle spindle stimulation. Several body sway metrics were also calculated for the same participants on an eyes-closed balance task. Based on regression analyses, multiple clusters of voxels were identified showing a significant relationship between muscle spindle stimulation-induced neural activity and maximum center of pressure excursion in the anterior-posterior direction. In this case, increased activation was associated with greater balance performance in parietal, frontal, and insular cortical areas, as well as structures within the basal ganglia. These correlated regions were age- and foot-stimulation side-independent and largely localized to right-sided areas of the brain thought to be involved in monitoring stimulus-driven shifts of attention. These findings support the notion that, beyond fundamental peripheral reflex mechanisms, central processing of proprioceptive signals from the foot is critical for balance control.

Vision Modulates Corticospinal Suppression in a Functionally Specific Manner during Movement of the Opposite Limb

The effect of vision on the excitability of corticospinal projections to the flexor carpi radialis (FCR) and extensor carpi radialis (ECR) muscles of right human forearm was investigated before and during discrete movement of the opposite limb. An external force opposed the initial phase of the movement (wrist flexion) and assisted the reverse phase, so that recruitment of the wrist extensors was minimized. Three conditions were used as follows: viewing the inactive right limb (Vision), viewing the mirror image of the moving left limb (Mirror), and with vision of the right limb occluded (No Vision). Transcranial magnetic stimulation was delivered to the left motor cortex: before, at the onset of, or during the left limb movement to obtain motor evoked potentials (MEPs) in the muscles of the right forearm. At and following movement onset, MEPs obtained in the right FCR were smaller in the Vision condition than in the Mirror and No Vision conditions. A distinct pattern of variation was obtained for the ECR. In all conditions, MEPs in this muscle were elevated upon or following movement of the opposite limb. An additional analysis of ipsilateral silent periods indicated that interhemispheric inhibition plays a role in mediating these effects. Activity-dependent changes in corticospinal output to a resting limb during discrete actions of the opposite limb are thus directly contingent upon where one looks. Furthermore, the extent to which vision exerts an influence upon projections to specific muscles varies in accordance with the functional contribution of their homologs to the intended action.