Apparatus is provided that is configured to be implanted in a body of a subject, comprising an implant structure having first and second portions thereof, a spool coupled to the implant structure in a vicinity of the first portion thereof, and a flexible member coupled at a first end thereof to the spool, and not attached at a second end thereof to the spool. The flexible member, in response to rotation of the spool in a first direction thereof, is configured to be wound around the spool, and, responsively, to pull the second end of the flexible member toward the first end of the implant structure, and responsively to draw the first and second portions of the implant structure toward each other. Other embodiments are also described.
