The increase in fracture rates and/or problems associated with missing bones due to accidents or various pathologies generates socio-health problems with a very high impact. Tissue engineering aims to offer some kind of strategy to promote the repair of damaged tissue or its restoration as close as possible to the original tissue. Among the alternatives proposed by this specialty, the development of scaffolds obtained from recombinant proteins is of special importance. Furthermore, science and technology have advanced to obtain recombinant chimera’s proteins. This review aims to offer a synthetic description of the latest and most outstanding advances made with these types of scaffolds, particularly emphasizing the main recombinant proteins that can be used to construct scaffolds in their own right, i.e., not only to impregnate them, but also to make scaffolds from their complex structure, with the purpose of being considered in bone regenerative medicine in the near future.

Large bone defects are a significant health problem today with various origins, including extensive trauma, tumours, or congenital musculoskeletal disorders. Tissue engineering, and in particular bone tissue engineering, aims to respond to this demand. As such, we propose a specific model based on Elastin-Like Recombinamers-based click-chemistry hydrogels given their high biocompatibility and their potent on bone regeneration effect conferred by different bioactive sequences. In this work we demonstrate, using biochemistry, histology, histomorphometry and imaging techniques, the biocompatibility of our matrix and its potent effect on bone regeneration in a model of bone parietal lesion in female New Zealand rabbits.

Background and Clinical Significance: Traumatic brain injury (TBI) represents a major public health concern due to its profound neurological, psychological, and socioeconomic consequences. Effective management is essential to optimize patient outcomes and reduce healthcare burden. In cases involving extensive bone loss or complex fractures, particularly when decompressive craniectomy (DC) is considered, secondary cranial reconstruction is typically required. However, DC is associated with prolonged hospitalization, multiple surgical interventions, an increased risk of complications, and higher costs. Case Presentation: We present the case of a 59-year-old male involved in a high-energy bicycle accident, sustaining severe craniofacial trauma with multiple midface fractures, a multifragmented left cranial fracture, and a left-sided epidural hematoma with brain compression. Hematoma evacuation and immediate primary reconstruction of the fractured skull using autologous bone were successfully performed, avoiding the need for DC. The patient recovered under intensive care and was transferred to a neurorehabilitation center. Conclusions: Primary reconstruction of large skull fractures using autologous bone should remain the goal, whenever possible, in order to avoid additional costs, risks, and complications.

En este proyecto se investigan los cambios que acontecen en el desarrollo y crecimiento de conejos hembras de la línea New Zealand (CoNZ) en sus huesos femorales. Los animales fueron mantenidas en jaulas individuales desde las 2 semanas de edad, con comida y agua ad libitum y se sacrificaron en tiempos mensualmente consecutivos: 1, 2, 3, 4, 5, y 6 meses. Tras la obtención de las piezas femorales, y a partir de estudios imagenológicos se determinaron los ángulos del cuello femoral (Af), la longitud total (L), la densidad mineral ósea total, del centro óseo y de la metáfisis femoral (DMOt, DMOco y DMOmf respectivamente), analizándose las variaciones intergrupales por el test Wilcoxon, y corrección de Bonferroni. Se realizaron estudios histológicos de los cortes descalcificados de las piezas femorales. Los análisis sobre los Af mostraron un incremento significativo durante el primer mes mientras que L se estabilizó a partir del 4to mes. Los valores de DMOt mostraron un plateau a partir del cuarto mes, si bien las DMOco y DMOmf ya a partir del tercer mes no mostraron incrementos significativos. Histológicamente se observó para el cuarto mes ausencia de las diferentes zonas características del cartílago de crecimiento metafisiario, con presencia únicamente de un pequeño remanente de células condrales. Desde el quinto mes se observa ausencia total de cartílago, con presencia únicamente de tejido osteoide (TO). La interpretación integrada de los resultados nos permite afirmar, que a partir del cuarto mes de desarrollo, el fémur de CoNZ adquiere características compatibles con un periodo de adultez. In this project we investigated the changes of femoral development and growth of female New Zealand rabbits (NZr). Animals were maintained in individual cages since they were two weeks old with food and water ad libitum, and were sacrificed monthly consecutively: 1, 2, 3, 4, 5 and 6. Radiological studies were made with femoral pieces to determine femoral neck angle (fnA), total length (L), total bone mineral density (tBMD), bone center mineral density (bcBMD) and femoral metaphysis bone mineral density (fmBMD). We analyzed intergroup variations with Wilcoxon test and Bonferroni correction. We also performed histologic studies with femoral pieces. The fnA analyzes showed a significant increase in the first month while L stabilized since the fourth month. tBMD showed a plateu since the fourth month, even though bcBMD and fmBMD did not show any significant changes since the third month. In histology it was observed the absence of all typical growth cartilage zones since the fourth month, with the only presence of small remaining cartilage cells. In the fifth month we observed complete absence of cartilage, and presence of osteoid tissue only. The integrated interpretation of the results allows us to affirm that since the fourth month of development the femur of NZr acquires characteristics compatible with the adulthood.