The effect of dehydration and irrigation on the healing of Achilles tendon: an experimental study.

Abstract

BACKGROUND: Air exposure is a factor that inhibits in vitro cellular proliferation and matrix synthesis in tendons. Aim of this experimental study was to evaluate effect of dehydration and irrigation on healing of Achilles tendon. METHODS: Achilles tenotomy was done in forty-five Sprague-Dawley rats. In control group, tendon was sutured immediately. In the remaining two groups, the Achilles tendons were allowed to direct exposure of air. Irrigation of Achilles tendon was performed in one of exposed groups, while irrigation was not done in other group. After 60 minutes, tendons of both groups were sutured same as control group. Rats were sacrificed at postoperative day 28. Achilles tendons were dissected and histological and biomechanical evaluations were performed. RESULTS: Histological evaluation revealed intense fibrosis formation with adhesion of tendon to surrounding tissues in the air exposed groups. The quantity of angiogenesis and inflammatory reaction were also higher in experimental groups regardless of irrigation. Air exposed tendons had higher tensile strength however lower stiffness than control group in biomechanical evaluation. CONCLUSION: Air exposure decreases quality of healing by increasing fibrosis and adherence formation. These negative effects of exposure to air were not counteracted by irrigation. However, air exposure didn't affect tensile strength of the healing.