Background: The risk of adhesion following flexor tendon repair, despite provision of rehabilitation by mobilization of the tendon with passive exercises without the risk of rupture, is not negligible. Active mobilization of tendons has recently been more frequently recommended to prevent adhesions of tendons. The tendon repair zone, which should withstand active traction forces, should maintain its strength until complete recovery of the tendon. For this purpose, a new treatment method named angular technique of interlocking (ATIK) has been developed. This method was compared with the Modified Kessler method, in vivo and in vitro.