The subject of the invention is a medical device for foot support related to a mechanism for attaching a calf support of the birthing bed, comprising a calf support (3) connected to a foot support (2) and a ball joint (5) connecting the calf support (3) and the foot support (2), wherein the ball part (5) comprises a pin (6) of the ball joint (5), a ball part (7) of the ball joint (5) and a housing (8), wherein the ball part (7) of the ball joint (5) is arranged in the housing (8), the medical device further comprising a pressing element (9) and a pre-biased spring (10), characterized in that the pre-biased spring (10) is arranged between the pressing element (9) and the fixed part (11) of the calf support (3), wherein at the end distant from the ball part (7) of the ball joint (5) the pre-biased spring abuts to adjacent fixed part (11) of the calf support (3) and at the end near the ball part (7) of the ball joint (5) it abuts to the movable pressing element (9) which is connected with the control member.