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1.
Enferm Intensiva (Engl Ed) ; 32(2): 79-87, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34099268

RESUMEN

OBJECTIVE: To determine the effectiveness of music therapy on anxiety and pain in critical polytraumatised patients admitted to the resuscitation unit of a tertiary level hospital in Spain. MATERIAL AND METHOD: Randomised clinical trial conducted in a tertiary level hospital, from June 2016 to May 2018. The study sample was 60 patients, 30 belonging to the intervention group (IG), and 30 to the control group (CG). The IG were given a 30-minute music session and heart rate (HR) and blood pressure (BP) were measured. The VAS (Visual Analogue Scale) was applied for anxiety and pain before and after each session. The same measures and scales were applied in the CG who did not receive a music session. The music session comprised 3 parts: the first was standard music selected by music therapists; the second was personalised, chosen by the patient and the third was a new standard. The intervention took place in a booth with headphones. RESULTS: Significant changes in anxiety levels (P<.01) were detected in the group of patients undergoing the intervention, measured with the VAS scale for anxiety, and pain levels (P<.01), measured with the VAS scale for pain. No significant differences were found in the physiological parameters of HR and BP. CONCLUSION: The use of music in critical polytraumatised patients reduces anxiety and pain levels, increasing the patient's well-being and improving the quality of care. Music therapy, therefore, is considered beneficial as a complementary measure in critical care units. It would be worthwhile to continue studies in this and other hospital areas.


Asunto(s)
Musicoterapia , Ansiedad/terapia , Trastornos de Ansiedad , Humanos , Dolor , Dimensión del Dolor
2.
Enferm Intensiva (Engl Ed) ; 32(2): 79-87, 2021.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33097396

RESUMEN

OBJECTIVE: To determine the effectiveness of music therapy on anxiety and pain in critical polytraumatised patients admitted to the resuscitation unit of a tertiary level hospital in Spain. MATERIAL AND METHOD: Randomised clinical trial conducted in a tertiary level hospital, from June 2016 to May 2018. The study sample was 60 patients, 30 belonging to the intervention group (IG), and 30 to the control group (CG). The IG were given a 30-minute music session and heart rate (HR) and blood pressure (BP) were measured. The VAS (Visual Analogue Scale) was applied for anxiety and pain before and after each session. The same measures and scales were applied in the CG who did not receive a music session. The music session comprised 3 parts: the first was standard music selected by music therapists; the second was personalised, chosen by the patient and the third was a new standard. The intervention took place in a booth with headphones. RESULTS: Significant changes in anxiety levels (P<.01) were detected in the group of patients undergoing the intervention, measured with the VAS scale for anxiety, and pain levels (P<.01), measured with the VAS scale for pain. No significant differences were found in the physiological parameters of HR and BP. CONCLUSION: The use of music in critical polytraumatised patients reduces anxiety and pain levels, increasing the patient's well-being and improving the quality of care. Music therapy, therefore, is considered beneficial as a complementary measure in critical care units. It would be worthwhile to continue studies in this and other hospital areas.

3.
Paediatr Drugs ; 21(3): 185-193, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31124053

RESUMEN

BACKGROUND: It has been 15 years since sirolimus, an mTOR inhibitor, received Food and Drug Administration approval to prevent acute rejection in kidney transplantation, and 8 years since its analog everolimus acquired the same status. Since then, these drugs have become more and more utilized and their immunosuppressive and antiproliferative properties have been tested in a great variety of clinical conditions, often achieving excellent results. Despite such positive evidence, the on-label indications for these rapalogs are still very restrictive, especially in children. AIMS: The aims of this study were to describe our center's experience with sirolimus and everolimus in managing rare pediatric conditions for which mTOR inhibitors have been reported as a therapeutic option, although without conclusive approval from regulatory agencies, and to evaluate safety and tolerability of the treatment at the prescribed doses. METHODS: All the subjects who received off-label sirolimus or everolimus at the Pediatric Department of the IRCCS Burlo Garofolo in the last 13 years were included. For each disease found in our case series, we reviewed the current scientific literature. RESULTS: Off-label treatment with rapalogs was prescribed in 16 children (11 males, 5 females, median age of 9.5 years, range 1-16 years). Seven had immunologic disorders: four autoimmune lymphoproliferative syndrome (ALPS), one multicentric Castleman disease (mCD), one activated PI3K delta kinase syndrome (APDS), and one immunodysregulation with polyendocrinopathy enteropathy X-linked (IPEX). Eight had proliferative disorders or vascular anomalies: one cystic lymphangioma, two Bannayan-Riley-Ruvalcaba syndrome (BRRS), one blue rubber bleb nevus syndrome (BRBNS), two tuberous sclerosis complex (TSC), and one low-flow mixed arterial and venous malformation. One case had congenital hyperinsulinism (CHI). The average dosage administered was 1 mg/m2 for sirolimus and 7 mg/m2 for everolimus. We experienced a good measurable clinical improvement in 14 patients. Nobody experienced serious adverse events (SAEs). The therapy was interrupted in two cases, for lack of efficacy and poor tolerance in one case and for occurrence of bacterial pneumonia in the other one. A review of the literature identified 101 published reports that met our inclusion criteria. CONCLUSIONS: Although use of mTOR inhibitors has been considered to be complicated, our experience shows that, using low dosages, it is possible to obtain relevant clinical improvements, with a good profile of safety and tolerability.


Asunto(s)
Antineoplásicos/uso terapéutico , Everolimus/uso terapéutico , Uso Fuera de lo Indicado/normas , Sirolimus/uso terapéutico , Adolescente , Antineoplásicos/farmacología , Niño , Preescolar , Everolimus/farmacología , Femenino , Humanos , Lactante , Masculino , Sirolimus/farmacología
4.
Reprod Domest Anim ; 51(6): 895-900, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27562911

RESUMEN

The objective of sperm selection media is selecting the best spermatozoa and to remove seminal plasma and diluent for using them in assisted reproductive techniques. It is known that individuals show different cryoresistance in response to the same freezing procedure. Our hypothesis was that the efficacy of selection media could be dissimilar for samples with different sperm quality after thawing. Epididymal sperm samples from mature Iberian red deer were collected and frozen. Males were classified as with high post-thaw sperm quality when sperm motility (SM) ≥ 70%, or as with low post-thaw sperm quality when SM ≤ 69%. Samples were centrifuged using the following density gradients (DG): Percoll® , Puresperm® and Bovipure™ , and several functional sperm parameters were assessed after sperm selecting and washing. Males classified with high sperm quality had higher post-thawing values (p > .05) for all parameters evaluated, except for linearity index, than those categorized as low sperm quality. After selection, some sperm characteristics improved (viability, apoptosis and mitochondrial activity) for both groups, showing the males with high sperm quality higher values in all sperm parameters except for kinematic traits and DNA fragmentation index (%DFI), regardless of DG. Bovipure™ yield lower values of sperm motility, viability, apoptosis and mitochondrial activity in relation to Percoll® and Puresperm® considering both quality groups. There was an interaction between the type of DG and sperm quality group for sperm viability (p = .040) and apoptosis (p = .003). Thus, Percoll® selected less live and more apoptotic spermatozoa than Puresperm® and Bovipure™ for males with low sperm quality. In conclusion, the DG are more efficient selecting spermatozoa from samples with high sperm quality, acting differently depending on initial sperm quality.


Asunto(s)
Separación Celular/veterinaria , Centrifugación por Gradiente de Densidad/veterinaria , Criopreservación/veterinaria , Ciervos/fisiología , Preservación de Semen/veterinaria , Animales , Separación Celular/métodos , Masculino , Análisis de Semen
5.
Int J Hematol ; 102(5): 626-32, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26084627

RESUMEN

The outcome of romiplostim for secondary failure of platelet recovery (SFPR) was investigated in children who had undergone hematopoietic stem cell transplantation (HSCT). Seven transfusion-dependent pediatric patients (median age 11 years), with platelet counts below 10 × 10(9)/L, received four weekly doses of subcutaneous romiplostim to treat SFPR developed after HSCT. All patients, except one (patient 4), became platelet transfusion-independent in the second week from the beginning of treatment and no patient needed to discontinue drug treatment because of adverse events. Romiplostim could represent a beneficial first-line treatment, but further studies are required.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Receptores Fc/administración & dosificación , Proteínas Recombinantes de Fusión/administración & dosificación , Trombocitopenia/tratamiento farmacológico , Trombopoyetina/administración & dosificación , Adolescente , Aloinjertos , Niño , Femenino , Humanos , Masculino , Recuento de Plaquetas , Trombocitopenia/sangre , Trombocitopenia/etiología
6.
Artículo en Inglés | MEDLINE | ID: mdl-25122411

RESUMEN

We introduce a quantum Monte Carlo algorithm to measure the Rényi entanglement entropies in systems of interacting bosons in the continuum. This approach is based on a path-integral ground state method that can be applied to interacting itinerant bosons in any spatial dimension with direct relevance to experimental systems of quantum fluids. We demonstrate how it may be used to compute spatial mode entanglement, particle partitioned entanglement, and the entanglement of particles, providing insights into quantum correlations generated by fluctuations, indistinguishability, and interactions. We present proof-of-principle calculations and benchmark against an exactly soluble model of interacting bosons in one spatial dimension. As this algorithm retains the fundamental polynomial scaling of quantum Monte Carlo when applied to sign-problem-free models, future applications should allow for the study of entanglement entropy in large-scale many-body systems of interacting bosons.


Asunto(s)
Entropía , Método de Montecarlo , Teoría Cuántica , Algoritmos , Partículas Elementales , Modelos Moleculares , Conformación Molecular
7.
J Colloid Interface Sci ; 376(1): 133-9, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22480397

RESUMEN

The influence of different dilution procedures on the properties of oil-in-water (O/W) nano-emulsions obtained by dilution of oil-in-water (O/W) and water-in-oil (W/O) microemulsions has been studied. The system water/SDS/cosurfactant/dodecane with either hexanol or pentanol as cosurfactant was chosen as model system. The dilution procedures consisted of adding water (or microemulsion) stepwise or at once over a microemulsion (or water). Starting emulsification from O/W microemulsions, nano-emulsions with droplet diameters of 20 nm are obtained, independently on the microemulsion composition and the dilution procedure used. In contrast, starting emulsification from W/O microemulsions, nano-emulsions are only obtained if the emulsification conditions allow reaching the equilibrium in an O/W microemulsion domain during the process. These conditions are achieved by stepwise addition of water over W/O microemulsions with O/S ratios at which a direct microemulsion domain is crossed during emulsification. The nature of the alcohol used as cosurfactant has been found to play a key role on the properties of the nano-emulsions obtained: nano-emulsions in the system using hexanol as cosurfactant are smaller in size, lower in polydispersity, and have a higher stability than those with pentanol.


Asunto(s)
Emulsiones/química , Aceites/química , Tensoactivos/química , Agua/química , Alcanos/química , Hexanoles/química , Pentanoles/química , Dodecil Sulfato de Sodio/química
8.
J Phys Condens Matter ; 23(16): 164216, 2011 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-21471617

RESUMEN

The magnetic insulator Gd(2)Sn(2)O(7) is one of many geometrically frustrated magnetic materials known to exhibit a nonzero muon spin polarization relaxation rate, λ(T), down to the lowest temperature (T) studied. Such behaviour is typically interpreted as signalling the presence of persistent spin dynamics (PSD) of the host material. In the case of Gd(2)Sn(2)O(7), such PSD comes as a surprise since magnetic specific heat measurements suggest conventional gapped magnons, which would naively lead to an exponentially vanishing λ(T) as T → 0. In contrast to most materials that display PSD, the ordered phase of Gd(2)Sn(2)O(7) is well characterized and both the nature and the magnitude of the interactions have been inferred from the magnetic structure and the temperature dependence of the magnetic specific heat. Based on this understanding, the temperature dependence of the muon spin polarization relaxation through the scattering of spin waves (magnons) is calculated. The result explicitly shows that, despite the unusual extensive number of weakly dispersive (gapped) excitations characterizing Gd(2)Sn(2)O(7), a remnant of the zero modes of the parent frustrated pyrochlore Heisenberg antiferromagnet, the temperature dependence of the calculated λ(T) differs dramatically from the experimental one. Indeed, the calculation conforms to the naive expectation of an exponential collapse of λ(T) at temperatures below ∼ 0.7 K. This result, for the first time, illustrates crisply and quantitatively the paradox that presents itself with the pervasive occurrence of PSD in highly frustrated magnetic systems as evinced by muon spin relaxation measurements.

9.
J Chem Phys ; 134(10): 104704, 2011 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-21405181

RESUMEN

An experimental study of the equilibrium properties and of the surface rheology of Langmuir monolayers of poly(methyl methacrylate) (PMMA) at the air/water interface has been carried out as a function of polymer concentration (Γ) and molecular weight (M(w)). Dilational and shear complex elasticity moduli covering a frequency range from 10(-3) to 0.2 Hz have been discussed. It was found that the air∕water interface behaves as a poor solvent for PMMA monolayers, thus suggesting that the polymer coils take collapsed soft-disks (pancakes) shape at the interface. The equilibrium and dynamic results suggest a fluid-to-soft-glass transition as the polymer concentration increases above a critical packing fraction at constant temperature. This two-dimensional transition is in agreement with results previously discussed for the dilational rheology of poly(4-hydroxystyrene) [F. Monroy, F. Ortega, R. G. Rubio, H. Ritacco, and D. Langevin, J. Chem. Phys. 95, 056103 (2005)]. Furthermore, the Γ-dependence of the relaxation dynamics of the monolayers suggests that the gel state may be considered as a fragile soft glass.

10.
Phys Chem Chem Phys ; 12(42): 14115-20, 2010 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-20859578

RESUMEN

We address a systematic study of the three-phase contact angle, θ, of microparticles at flat fluid-liquid interfaces by using different experimental methods. We measured the dependence of θ not only on the particle chemical composition and size, but also on the solvent used to spread the microparticles onto the fluid interface. We found a non-expected and non-regular dependence of θ with size, chemical nature and spreading solvent used for the different particles studied. We propose that these dependences are due to porosity/roughness of the particles that allows the adsorption of the spreading solvent onto the solid particle surface. This conclusion is supported by the values of the line tensions estimated for the different systems.

11.
Eur Phys J E Soft Matter ; 31(1): 89-94, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20101518

RESUMEN

The topic of the gel transition in two dimensions is revisited by considering data on the shear elasticity of Langmuir monolayers of different spherical objects. Amorphous freezing can be associated to structural percolation in a lattice able to resist shear stresses. The shear modulus and its dependence on the packing fraction are found to strongly depend on the details of the interaction potential and largely differ from expectations for entropic networks. This behaviour can be interpreted in terms of more elaborated percolation theories including central forces and bond-bending forces.


Asunto(s)
Congelación , Geles/química , Elasticidad , Entropía , Resistencia al Corte , Propiedades de Superficie , Tensión Superficial , Torsión Mecánica
12.
Langmuir ; 25(13): 7393-400, 2009 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-19326872

RESUMEN

The surface shear rheology of Langmuir monolayers of poly(methyl methacrylate) (PMMA) has been studied as a function of polymer concentration (Gamma) and molecular weight (N). Two different rheology techniques were used, one based on free damped oscillations of a ring with a sharp edge and the other based on a forced oscillation of a biconical disk. Both instruments were used in the oscillatory mode at comparable oscillation frequency and amplitude, which gave access to the viscoelastic shear modulus (S). The two instruments, working in different viscosity ranges, provide complementary and mutually compatible data. The results obtained for four PMMA samples of molecular weight between 8x10(3) and 2.7x10(5) g.mol(-1) show powerlike behavior as S approximately Gamma10 and S approximately N4. These strong dependences suggest a structural scenario based on the 2D percolation of the polymer pancakes.

13.
Br J Sports Med ; 43(11): 818-24, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19174412

RESUMEN

OBJECTIVE: This study is a statistical analysis to establish whether a correlation exists between the level and degree of rectus femoris (RF) central tendon injury and the amount of time that an athlete is unable to participate subsequently, referred to as "sports participation absence" (SPA). DESIGN: Causal-comparative study. PATIENTS: 35 players from two high-level Spanish soccer teams with an injury to the central tendon of the RF based on clinical and ultrasound criteria. MAIN OUTCOME MEASURE: Ultrasound examination was performed with an 8-2 MHz linear multifrequency transducer. All studies included both longitudinal and transverse RF sections. RESULTS: At the proximal level the SPA time is 45.1 days when the injury length is 4.0 cm. This value increases by 5.3 days with each 1 cm increase in the length of injury. In the case of distal level injury, SPA time is 32.9 days when the injury length is 3.9 cm. This value increases by 3.4 days with each 1 cm increase. In the total representative sample, SPA time when the injury length is 4.2 cm corresponds to 39.1 days. This value increases by 4.2 days per length unit. CONCLUSIONS: RF central tendon injury at the proximal level is associated with a greater SPA time than at the distal level. Patients with a grade II injury have an SPA time longer than those with a grade I injury whether the injury is located proximal or distal.


Asunto(s)
Músculo Cuádriceps/lesiones , Fútbol/lesiones , Traumatismos de los Tendones/diagnóstico por imagen , Absentismo , Adolescente , Adulto , Estudios de Casos y Controles , Humanos , Pronóstico , Músculo Cuádriceps/diagnóstico por imagen , Rotura/diagnóstico por imagen , Rotura/rehabilitación , Traumatismos de los Tendones/rehabilitación , Ultrasonografía , Adulto Joven
14.
Phys Rev Lett ; 99(9): 097201, 2007 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-17931029

RESUMEN

We have measured the low-temperature specific heat of the geometrically frustrated pyrochlore Heisenberg antiferromagnet Gd2Sn2O7 in zero magnetic field. The specific heat is found to drop exponentially below approximately 350 mK. This provides evidence for a gapped spin-wave spectrum due to an anisotropy resulting from single-ion effects and long-range dipolar interactions. The data are well fitted by linear spin-wave theory, ruling out unconventional low-energy magnetic excitations in this system, and allowing a determination of the pertinent exchange interactions in this material.

15.
Acta Orthop Belg ; 68(2): 163-7, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12051003

RESUMEN

For revision knee surgery with uncontained tibial bone defects, the authors report the containment of compacted morsellized allograft using metal-wire mesh, followed by implantation of a cemented total knee prosthesis. This method is comparable to the "impaction grafting technique" described for revision hip surgery and could be an alternative to metal wedges, augmented components, custom-made implants, polymethyl-methacrylate or structural bone grafts to solve some problems of cavitary and segmental bone defects in revision total knee arthroplasty.


Asunto(s)
Artritis Reumatoide/cirugía , Artroplastia de Reemplazo de Rodilla/métodos , Cementos para Huesos , Trasplante Óseo/métodos , Complicaciones Posoperatorias/cirugía , Mallas Quirúrgicas , Adulto , Artroplastia de Reemplazo de Rodilla/efectos adversos , Femenino , Humanos , Diseño de Prótesis
16.
J Neurooncol ; 53(2): 87-98, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11716073

RESUMEN

OBJECTIVE: The dynamic mechanisms underlying the three-dimensional invasive paradigm of C6 astrocytoma cells has been assessed. METHODS: Spheroids of C6 astrocytoma cells were implanted into three-dimensional collagen type I gels (vitrogen 100) and individual C6 astrocytoma cell invasion monitored. Time-lapsed videomicroscopy was used to assess the dynamic components of cell invasion in three dimensions while scanning and transmission electron microscopy were used to assess matrix architecture and the static aspects of cell invasion. RESULTS: Videomicroscopy outlined an invasion paradigm continuum with repeating phases. A cell surface ruffling phase was followed by invadopodia extension and pull up phases. For some cells the collagen type I matrix extracellular matrix appeared to modify the ability of C6 cells to carry out their invasion paradigm. CONCLUSIONS: C6 astrocytoma cells invading a three-dimensional collagen type I matrix utilize a invasion paradigm made up of a number of phases. A better understanding of the dynamic invasion paradigms of malignant glial cells may be useful in the development of effective treatment strategies to prevent or modify malignant glioma invasion.


Asunto(s)
Astrocitoma/patología , Neoplasias Encefálicas/patología , Invasividad Neoplásica , Animales , Extensiones de la Superficie Celular/ultraestructura , Colágeno , Diseño de Equipo , Geles , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Microscopía por Video/instrumentación , Modelos Biológicos , Ratas , Esferoides Celulares/patología , Células Tumorales Cultivadas/patología
17.
Int Orthop ; 24(2): 104-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10894381

RESUMEN

We report a study of 2 surgical approaches to the knee in 42 consecutive patients undergoing a total arthroplasty. They were divided into 2 groups. In Group 1 (n=17) the knee was exposed through classic medial parapatellar arthrotomy and in Group 2 (n=25) the knee was approached through the fibers of the medial vastus. Preoperative assessment did not reveal any statistical differences between the groups, and blood loss, operation time, biochemistry values and radiographic evaluation were also similar. However, a higher number of lateral releases, a loss of knee extension and a reduced range of motion were significantly associated with classical parapatellar arthrotomy. As the number of operative or postoperative complications was not increased, we recommend the mid-vastus approach for total knee arthroplasty.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Anciano , Femenino , Humanos , Masculino , Periodo Posoperatorio , Estudios Retrospectivos , Resultado del Tratamiento
19.
J Arthroplasty ; 13(5): 552-8, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9726321

RESUMEN

A prospective study of 116 consecutive Kinemax cemented posterior cruciate ligament-retaining total knee arthroplasties was carried out. Similar surgical technique was used with a single variable: 61 were implanted using intramedullary guides on the tibia and 55 were implanted using extramedullary guides on the tibia. A radiographic study was performed after at least 1 year of follow-up to evaluate postoperative component position and compare the difference in the accuracy of positioning of the femoral and tibial components. Radiographic analysis showed that satisfactory position was achieved using both types of instrumentation. No statistically significant difference was observed in either the coronal or sagittal plane of the femoral component and the sagittal plane positioning of the tibial component. However, the coronal plane positioning of the tibial component revealed a statistically significant difference (P < .01), with intramedullary guides being superior to extramedullary guides. Also observed, was that using either technique, patients with less accurate postoperative positioning tended to be obese, with wide intramedullary canals. Patients with significant extraarticular deformities, marked bowing, and those with prior surgery or fractures may not be suitable for intramedullary guides, and they may require the use of extramedullary guides and intraoperative radiographic control. The ideal indication for the use of intramedullary instrumentation is in the patient who is not obese, with no extraarticular deformity, and with a well-defined, but not excessively wide, tibial medullary canal. Since tibial component malalignment in general, and coronal plane malalignment in particular, may adversely affect the long-term survival of total knee arthroplasties, the use of intramedullary alignment instrumentation is recommended when possible.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Prótesis de la Rodilla , Anciano , Estudios de Casos y Controles , Cementación , Femenino , Estudios de Seguimiento , Humanos , Fijadores Internos , Articulación de la Rodilla/diagnóstico por imagen , Masculino , Diseño de Prótesis , Radiografía , Tibia/cirugía , Factores de Tiempo
20.
J Arthroplasty ; 13(8): 916-22, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9880185

RESUMEN

Although long-term studies report successful results with total knee arthroplasty (TKA), performed with or without posterior cruciate ligament (PCL) retention, controversy exists as to which is preferable in regard to patient outcome and satisfaction. The possible proprioceptive role of the PCL may account for a more normal feeling of the arthroplasty. Although the PCL has been examined using various histological techniques, immunohistochemical techniques are the most sensitive for neural elements. Therefore an immunohistochemical study was designed to determine the patterns of innervation, the morphological types of the proprioceptors, and their immunohistochemical profile. During TKA, samples were obtained from 22 osteoarthritic PCLs and subjected to immunohistochemical analysis with mouse monoclonal antibodies against neurofilament protein (NFP), S100 protein (S100P), epithelial membrane antigen (EMA), and vimentin (all present in neuromechanoreceptors). Three normal PCLs from cadaveric specimens were also obtained and analyzed for comparison. Five types of sensory corpuscles were observed in both the normal and the arthritic PCLs: simple lamellar, Pacini-like, Ruffini, Krause-like, and morphologically unclassified. Their structure included a central axon, inner core, and capsule in lamellar and Pacini corpuscles and variable intracorpuscular axons and periaxonal cells in the Ruffini and Krause-like corpuscles. The immunohistochemical profile showed the central axon to have NFP immunoreactivity, periaxonal cells to have S100P and vimentin immunoreactivity, and the capsule to have EMA and vimentin immunoreactivity. Nerve fibers and free nerve endings displayed NFP and S100P immunoreactivity. The immunohistochemical profile of the PCL sensory corpuscles is almost identical to that of cutaneous sensory corpuscles. Some prior histological studies of the PCL reported Golgi-like mechanoreceptors, and others found encapsulated corpuscles but no Golgi-like structures. This report determined the innervation of the PCL by the more sensitive immunohistochemical means, revealing four major types of encapsulated mechanoreceptors. The plentiful and varied types of encapsulated mechanoreceptors found in even the arthritic PCL suggests a rich proprioceptive role. It is controversial as to whether preservation of the PCL at TKA improves postoperative proprioception. Our findings tend to support those clinical reports of improved proprioception after PCL-retaining versus PCL-substituting TKAs. The presence of many and varied types of mechanoreceptors may account for the improved stair climbing reported in patients with PCL-retaining TKA and may contribute to patient satisfaction and a more normal feeling after TKA.


Asunto(s)
Mecanorreceptores/anatomía & histología , Ligamento Cruzado Posterior/inervación , Propiocepción/fisiología , Artroplastia de Reemplazo de Rodilla/métodos , Estudios de Casos y Controles , Femenino , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Mucina-1/análisis , Proteínas del Tejido Nervioso/análisis , Osteoartritis de la Rodilla/patología , Osteoartritis de la Rodilla/cirugía , Ligamento Cruzado Posterior/química , Ligamento Cruzado Posterior/fisiología , Vimentina/análisis
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