System evaluation on reamed and non-reamed intramedullary nailing in the treatment of closed tibial fracture

PURPOSE: To systematically evaluate the clinical efficacy of reamed and nonreamed intramedullary nailing in treatment of closed tibial fractures with Cochrane systematic review methods. METHODS: According to the Cochrane systematic review methods, literatures were retrieved from Cochrane library, PubMed, EMbase and other database. Randomized controlled trials (RCTs) and quasi-randomized controlled clinical trials about reamed and nonreamed intramedullary nailing in the treatment of closed tibial fractures were collected and RevMan 5.0 was chosen for meta-analysis. RESULTS: A total of seven studies were included in this meta-analysis. Reamed intramedullary nailing was better than nonreamed intramedullary nailing in nonunion rate [P = 0.02, RR = 0.46, 95% CI: (0.24, 0.91)] and implant failure rate [P <0.0001, RR = 0.36, 95% CI: (0.22, 0.57)]. No statistically significant difference was observed in malunion rate, compartment syndrome rate, postoperative infection [P = 0.18, RR = 0.50, 95% CI: (0.18, 1.383); P = 0 43, RR = 0.77, 95% CI: (0.40, 1.48); P = 0.27, RR = 0.38, 95% CI: (0.01, 7.87)]. CONCLUSION: Compared with the nonreamed intramedullary nailing, reamed intramedullary nailing can lead to better outcome in the treatment of closed tibial fractures.

Correlation between Innervation of Skeletal Muscles and Myoblast Stem Cells / Correlación entre la Inervación de los Músculos Esqueléticos y las Células Precursoras Mioblásticas

In order to explore the change rule of myoblast stem cells (satellite cells, SCs) in the denervated and re-innervated muscle and to investigate the cellular mechanism of the morphological and functional changes of the muscle, denervated muscle atrophy and nerve regeneration models were established in one-month-old rats. Postoperative indexes such as muscle wet weight, cell section areas, content of collagen fibers and DNA, electrophysiology, numbers of SCs in the triceps muscle of calf were dynamically tested. After denervation, the muscle wet weight and cell area reduced rapidly, and the collagen fiber content increased slowly. The number of SCs increased at first, and then declined suddenly two months later. From 4 to 5 weeks after re-neuralization, muscle action potentials could be evoked, but the best innervation effect was found in the groups, which received re-neuralization at 2 months and 3 months after denervation. Denervation causes a progressive progress of muscle atrophy. SCs proliferate within 3 months after denervation, and then atrophy becomes irreversible from 4 months. At 4 or 5 weeks after re-neuralization, muscle action potentials can be evoked. Re-neuralization at 2 months and 3 months after denervation can achieve a good effect on the functional recovery of the atrophic muscle.

Con el fin de explorar la regla de cambio de las células precursoras mioblásticas (células satélite, CSs) en el músculo denervado y re-inervado e investigar el mecanismo celular de los cambios morfológicos y funcionales del músculo, se establecieron, en ratas de un mes de edad, modelos de atrofia del músculo denervado y regeneración del nervio. Fueron examinados de manera dinámica índices postoperatorios tales como, el peso húmedo del músculo, áreas celulares de la sección, contenido de fibras de colágeno y ADN, electrofisiología, número de CSs en el músculo tríceps de las crías. Luego de la denervación, el peso del músculo húmedo y el área celular se redujeron rápidamente, mientras que el contenido de fibras colágenas aumentó lentamente. El número de CSs aumentó al inicio, pero más tarde, a los dos meses, disminuyó repentinamente. Entre las 4 a 5 semanas después de la reneuralización, los potenciales de acción muscular pudieron ser evocados, pero el mejor efecto de inervación se encontró en los grupos que recibieron reneuralización a los 2 y 3 meses después de la denervación. La denervación causó un avance progresivo de la atrofia muscular. Las CSs proliferaron dentro de los primeros 3 meses post-denervación, y luego de los 4 meses la atrofia fue irreversible. A las 4 o 5 semanas después de la reneuralizacón, los potenciales de acción muscular pueden ser evocados. La reneuralización a los 2 y 3 meses después de la denervación puede lograr un buen efecto en la recuperación funcional del músculo atrófico.