An apparatus for treating a tennis elbow by percutaneous intervention, includes:a body having an actuating element,a fixing part arranged to fixably position the body,a positioning device connected to the body, including a positioning part moveable by the actuating element,a holder releasably connected to the positioning part, and including a top part for the releasable connection to the positioning part and a bottom part defining a support surface for supporting an elbow tendon region of a person to be treated, the support surface, the top and bottom parts being connected by one or more connecting members, the holder including a holder part with a number of penetration elements arranged thereon, wherein the top and bottom parts are spaced-apart at such a distance that, before penetration of the elbow tendon, the penetration tips of the penetration elements are covered by the bottom part.
