Study of fracture healing in protein malnutrition.

The present study was designed to assess the effects of nutrition on fracture healing in a controlled animal model. Tibial fractures were studied in 115 Wistar rats divided into four groups: group 1,50 control animals kept on a normal diet; groups 2 and 3, 45 protein-deprived animals, and group 4, 20 animals submitted to protein malnutrition before the fracture and then placed on a normal laboratory diet. The parameters evaluated during the study were: variation in animal weight during the experiment (confirmation of protein malnutrition), fracture healing as determined by bone callus radiology, macroscopic evaluation of bone callus mechanical resistance, and histological fracture examination by common light microscopy after staining with hematoxylin-eosin. The results showed the beneficial effects of protein nutrition support on the healing of lone bone fractures. Callus formation was significantly improved in groups 1 and 4 compared to groups 2 and 3. In groups 1 and 4, callus development was normal, with regular bone tissue formation, whereas in groups 2 and 3 there was a large amount of fibrous-connective tissue with scarce formation of osseous tissue.