A medical device is insertable and/or implantable into a body of a patient. The medical device includes a plurality of hollow and/or collapsible tines which are adapted to assist in deployment of the medical device into the body and in preventing inadvertent removal or dislodging of the medical device from the body. The tines are coupled to the medical device body at a coupling end and extend away from the device to a free end. The tines can have a number of configurations such as cylindrical or cone shaped. In addition, the cross section of the free end of the tines can be elliptical, where the free end extends to a tip. Another cross section includes a semi-circle including an open portion which can face towards or away from the medical device body. The tines also include coiled structures which can have a radial axis perpendicular to the radial axis of the medical device.