Strength Development of skin Incisions in young and old Rats

Abstract

Studies of strength development in standardized skin incisions in young and old rats have shown that the breaking load is significantly higher in young animals than in old animals at days 4 and 21 after wound infliction, but not different at days 7 and 14. Skin was, on average, 40% thicker in the old animals than in the young. Breaking strength values (breaking load per unit cross-sectional wound area) were found to be lower in old animals than in young animals at all postsurgical intervals studied. This strongly suggests that the capacity for repair and regeneration is decreased in old animals. Previous studies claiming that strength development is unimpaired in wounds in old animals have not taken into consideration differences in skin thickness (wound area) at different ages.