Method and apparatus for adjusting a gastrointestinal restriction device

A gastrointestinal implant, comprising:

• a flexible adjustable body comprising a contact surface configured for at least partially engaging a surface of a gastrointestinal tract of a mammal, the contact surface having a first perimeter;
• an opposing surface, radially opposed to the contact surface, the opposing surface having a second perimeter, the contact surface having undulating increases and decreases in radius along the first perimeter and the opposing surface having substantially matched increases and decreases in radius along the second perimeter;
• an actuator configured to change the configurations of the contact surface and the opposing surface in response to rotational movement of an implantable interface operatively coupled to the actuator via a drive transmission, the actuator comprising a tensile member having a proximal end and distal end, the tensile member coupled to the flexible adjustable body;
• an external adjustment device configured to non-invasively couple to the implantable interface from a location external to the mammal;
• wherein movement of at least a portion of the implantable interface results in a change in the dimension or configuration of the contact surface;
• wherein the actuator is disposed at least partially within the flexible adjustable body about a plurality of ribs contained therein, wherein the ribs include holes;
• and
• wherein the actuator passes through at least a plurality of the holes.