A drainage catheter includes an elongated tubular member and a locking assembly. The locking assembly includes a first protruding element and a collar. The first protruding element is disposed proximal to a port in the tubular member through which a proximal portion of a tension member may exit. The collar is coaxially disposed about the tubular member and has a second protruding element projecting from an interior surface of the collar. The collar is configured for longitudinal sliding movement relative to the tubular member such that the collar may be moved along the tubular member toward the proximal end of the tubular member thereby interacting with the first protruding element and securing the proximal portion of the tension member between the first protruding element and the collar.