Nerve gaps repaired with acellular nerve allografts recellularized with Schwann-like cells: Preclinical trial.

BACKGROUND: Acellular nerve allografts (ANA) recellularized with mesenchymal stem cells (MSC) or Schwann cells (SC) are, at present, a therapeutic option for peripheral nerve injuries (PNI). This study aimed to evaluate the regenerative and functional capacity of a recellularized allograft (RA) compared with autograft nerve reconstruction in PNI. METHODS: Fourteen ovines were randomly included in two groups (n=7). A peroneal nerve gap 30 mm in length was excised, and nerve repair was performed by the transplantation of either an autograft or a recellularized allograft with SC-like cells. Evaluations included a histomorphological analysis of the ANA, MSC pre differentiated into SC-like cells, at one year follow-up functional limb recovery (support and gait), and nerve regeneration using neurophysiological tests and histomorphometric analysis. All evaluations were compared with the contralateral hindlimb as the control. RESULTS: The nerve allograft was successfully decellularized and more than 70% of MSC were pre differentiated into SC-like cells. Functional assessment in both treated groups improved similarly over time (p <0.05). Neurophysiological results (latency, amplitude, and conduction velocity) also improved in both treated groups at twelve months. Histological results demonstrated a less organized arrangement of nerve fibers (p <0.05) with an active remyelination process (p <0.05) in both treated groups compared with controls at twelve months. CONCLUSIONS: ANA recellularized with SC-like cells proved to be a successful treatment for nerve gaps. Motor recovery and nerve regeneration were satisfactorily achieved in both graft groups compared with their contralateral nontreated nerves. This approach could be useful for the clinical therapy of PNI.

[Tropical pyomyositis of the iliacus, obturator internus, piriformis and psoas major muscles in an immunocompetent patient with claudication]. / Piomiositis tropical del músculo ilíaco, obturador interno, piriforme y psoas mayor en un paciente inmunocompetente con claudicación.

INTRODUCTION: Pyomyositis is a term that denotes pyogenic infection usually primary skeletal muscle, associated with hematogenous dispersion due to transient bacteremia, or penetrating trauma, usually forming abscesses. Classically described frequently in tropical areas and predominantly affecting the lower limb musculature, however, in recent decades it has increasingly been associated with areas of temperate climates and relatively more frequently in immunosuppressed patients, being the patients under 30 years the most affected. CLINICAL CASE: Male of 15 years without relevant medical history. The patient had no history of trauma, falls, surgical interventions, infections or any other systemic condition. He came because of a clinical picture of 7 days of evolution characterized by pain referred to the groin and left iliac crest area associated with claudication and hyperthermia not quantified, which yielded partially to NSAIDs and paracetamol, but without achieving improvement so it is taken emergency by relatives. CONCLUSIONS: It is necessary to bear in mind this pathology when performing the differential diagnostic approach of a patient presenting with pain and functional limitation of some joint associated with data suggestive of an infectious or inflammatory process.

INTRODUCCIÓN: La piomiositis es un término que denota infección piógena por lo general primaria de músculo esquelético. Clásicamente descrita de manera frecuente en zonas tropicales y en pacientes inmunocomprometidos; sin embargo, en las últimas décadas se observa cada vez más en zonas de climas templados y con relativa mayor frecuencia en pacientes inmunocompetentes, siendo el grupo etario más afectado el de menores de 30 años. CASO CLÍNICO: Masculino de 15 años sin antecedentes médicos de relevancia. Acude por presentar cuadro clínico de siete días de evolución caracterizado por dolor referido en ingle y zona de la cresta ilíaca izquierda asociado a claudicación e hipertermia no cuantificada, que cedían parcialmente a AINES y paracetamol, pero sin lograr mejoría, por lo que es llevado a urgencias por familiares. CONCLUSIONES: Es necesario tener en mente esta patología al momento de realizar el abordaje diagnóstico diferencial de un paciente que se presenta con dolor y limitación funcional de alguna articulación asociada a datos sugestivos de un proceso infeccioso o inflamatorio.

[External fixation with reconstruction rail system as a treatment for pseudoarthrosis of the distal femur]. / Fijación externa con sistema de riel de reconstrucción como tratamiento para seudoartrosis del fémur distal.

Distal femur pseudoarthrosis also called «distal femur non-union¼ (DFNU) represents a rare complication associated with a fracture caused by high-energy trauma; its treatment is controversial, as there is a wide variety of surgical techniques that can be implemented, from open reduction plus internal fixation with plates, to the use of fixed angle plates combined with bone autograft. We expose the case of a 24-year-old man who shows up for consultation with the history of having presented a left femoral supracondylar fracture with a year of evolution, treated by osteosynthesis of the distal femur with dynamic condylar screws (DCS plate); developed a torpid evolution with severe pain in the distal third of the left thigh and functional limitation, developed a progressive varus deformity of the left thigh that caused a shortening of 3.8 cm of the limb. A focus of pseudoarthrosis was identified, which was surgically removed, the intramedullary canal was recanalized, and a lateral closed wedge osteotomy was performed to correct the angulation and allow reduction. 5.5 mm (three proximal and three distal) hydroxyapatite screws and an external fixator were placed. In addition, a review of the literature focused on the use of external fixation was carried out as a treatment for the pseudoarthrosis of the distal femur.

La seudoartrosis del fémur distal, también llamada «no unión del fémur distal¼ (NUFD), representa una complicación poco frecuente asociada a una fractura causada por un traumatismo de alta energía; su tratamiento es controversial, ya que existe una gran variedad técnicas quirúrgicas que pueden ser implementadas desde la reducción abierta más la fijación interna con placas hasta el uso de placas de ángulo fijo combinadas con autoinjerto óseo. Exponemos el caso de un hombre de 24 años de edad, el cual se presenta a la consulta con el antecedente de haber sufrido una fractura supracondílea femoral izquierda con un año de evolución, tratada mediante una osteosíntesis del fémur distal con tornillos condilares dinámicos (placa DCS); mostró una evolución tórpida con dolor severo en el tercio distal del muslo izquierdo y limitación funcional, desarrolló una deformidad en varo progresiva del muslo izquierdo que causó un acortamiento de 3.8 cm de la extremidad. Se identificó un foco de seudoartrosis, el cual se retiró quirúrgicamente, se recanalizó el canal intramedular y se realizó una osteotomía de cuña cerrada lateral para corregir la angulación y permitir la reducción. Se colocaron tornillos de hidroxiapatita de 5.5 mm (tres proximales y tres distales) y un fijador externo. Además se hizo una revisión de la literatura enfocada en el uso de la fijación externa como tratamiento de la seudoartrosis del fémur distal.

Human amniotic membrane intra-articular injection prevents cartilage damage in an osteoarthritis model.

Osteoarthritis (OA) is a degenerative joint disease that affects the soft tissues and bones of involved articulations as a result of deregulation between synthesis and extracellular matrix degradation in articular cartilage. The present study evaluated the effect of intra-articular injection of human amniotic membrane (AM) as a treatment in an OA animal model in the knee. Chemical OA was developed in the knees of New Zealand rabbits. Once OA was established, the right knees only were treated with an intra-articular injection of human AM, with the left knees considered as a negative control group. The evaluation was performed at 3 and 6 weeks post-treatment. At 3 weeks post-injection, the cartilage exhibited fibrillation, erosion, cracks and cell clusters in the negative control group, but not in the treated group (P=0.028). At 6 weeks post-injection, the left knees exhibited hypertrophy, cracks, cell clusters, decreased matrix staining and structure loss. However, the right knees exhibited cell clusters without evidence of disruption in cartilage integrity (P=0.015). These results suggested that the intra-articular injection of human AM delays histological changes of cartilage in OA.

[Installed Capacity Perception Survey for the Training of Residents Program in Orthopedics and Care Needs in Acute and Chronic Musculoskeletal Pathology in Mexico]. / Encuesta de Percepción en Capacidad Instalada para la Formación de Médicos Residentes en Ortopedia (Traumatología) y Necesidades de la Atención en Patología Musculoesquelética Aguda y Crónica en México. Primera Parte.

INTRODUCTION: It is essential that orthopaedic resident physicians be highly proficient in all aspects, considering the balance between supply, demand, need and context. Fundamental to identify the capacity and quality installed for their training in Mexico. MATERIAL AND METHODS: Observational Study, transverse, non-probabilistic sampling-conglomerates, in two phases. The instrument has 8 domains, 57 variables and 4,867 items. 60 graduate professors of 20 states, 50 hospital sites, 22 university programs. RESULTS: 1,038 years of experience (collective intelligence), 17 years of experience/teacher (01 to 50 years). Identified: acute pathology 30 (2 to 90%), chronic pathology 30 (5 to 96%), patients 15 years, 10 (3 to 30%), patients between 15 and 65 years, 47 (2 to 78%), patients 65 years, 20 (2 to 60%), number of beds/seat 20 (2 to 510), number of clinics 3 (1 to 48), number of surgical procedures/headquarters per year at the national level, was 960 (50 to 24,650). The national average per resident doctor is 362 surgeries/year with 1,450 surgical times/year. CONCLUSIONS: The needs and resources for the training of physicians specializing in orthopedics/traumatology are highly heterogeneous, so it should be adapted to the epidemiological needs of the region of influence, in an area of epidemiological transition. 62.2% expressed not having or have bad academic and scientific infrastructure at its headquarters, more than 50% without rotation overseas and 90% without regular scientific production.

INTRODUCCIÓN: Es fundamental que los médicos residentes de ortopedia (traumatología) sean altamente competentes en todos los aspectos, considerando el equilibrio entre la oferta, demanda, necesidad y contexto. Es primordial identificar la capacidad y calidad instalada para su formación en México. MATERIAL Y MÉTODOS: Estudio observacional, transversal, muestreo no probabilístico-conglomerados, en dos fases. El instrumento tiene ocho dominios, 57 variables y 4,867 ítems. Sesenta profesores de postgrado de 20 estados, 50 sedes hospitalarias, 22 programas universitarios. RESULTADOS: 1,038 años de experiencia (inteligencia colectiva), 17 años de experiencia/profesor (01 a 50 años). Se identificó: patología aguda 30 (2 a 90%), patología crónica 30 (5 a 96%), pacientes 15 años, 10 (3 a 30%), pacientes entre 15 y 65 años, 47 (2 a 78%), pacientes 65 años, 20 (2 a 60%), número de camas/sede 20 (2 a 510), número de consultorios 3 (1 a 48), el número de procedimientos quirúrgicos/sede al año a nivel nacional fue de 960 (50 a 24,650). La media nacional por médico residente es de 362 cirugías/año con 1,450 momentos quirúrgicos/año. CONCLUSIONES: Las necesidades y recursos para la formación de médicos especialistas en ortopedia/traumatología son en alto grado heterogéneos, por lo cual se debería adaptar a las necesidades epidemiológicas de la región de influencia, en un ámbito de transición epidemiológica. Sesenta y dos punto dos por ciento expresó no tener o tener deficiente infraestructura académica y científica en su sede, más de 50% sin rotación al extranjero y 90% sin producción científica regular.