A drainage catheter includes an elongated tubular member, a locking assembly engaged with a proximal end of the tubular member, and a tension member for drawing a distal end of the tubular member into a desired configuration. The locking assembly includes a connector, a locking arm, and a locking mechanism. The connector has an exterior surface profile that corresponds with an interior surface profile of the locking arm. The locking arm is pivotably attached to the connector to enable pivoting movement of the locking arm between an unlocked position and a locked position whereby the tension member is secured between the locking arm and the connector when the arm is in the locked position. The locking assembly may alternatively comprise a connector and a sliding sleeve or a connector having a clamping element disposed therein.