The Effect of Erythropoietin on Rat Rotator Cuff Repair Model: An Experimental Study

Objectives: The aim of this study was to determine whether erythropoietin (EPO) can enhance rotator cuff healing in rats as measured by histological analysis and biomechanical testing.

Methods: A total of 72 rats were included in this study. In the control group ( = 24), repair was performed without EPO injection. In the local group ( = 24) EPO was injected in the repair site. In the systemic group ( = 24) EPO was administered as an intraperitoneal injection every day for 10 days after repair. Rats were euthanized on day 10 ( = 12 from each group) and day 28 ( = 12 from each group). Histopathological ( = 6) and biomechanical examinations ( = 6) were done.

Results: Biomechanical results reveal that the maximum load to failure values of the early control group were statistically lower than those of the early systemic group ( = 0.006). Comparing the the total Bonar values histopathologically reveal that the early systemic group was statistically higher than those of the early local group ( = 0.043). The late control group was statistically higher than those of the late local group ( = 0.003) and the late systemic group ( = 0.034). The late systemic group was statistically higher than those of the late local group ( = 0.003).

Conclusions: EPO application had a positive effect biomechanically in the early euthanized group and histopathologically in the late euthanized group.