Medical device adapter with wrist mechanism

A surgical device having a drive mechanism comprising:

• a proximal transmission shaft defining a first longitudinal axis, the proximal transmission shaft including a connector sleeve disposed at a proximal end thereof and a first gear disposed at a distal end thereof, wherein the connector sleeve is couplable to the surgical device;
• a middle transmission shaft including a second gear disposed at a proximal end thereof and meshingly engaged with the first gear and a third gear disposed at a distal end thereof, the middle transmission shaft defining a second longitudinal axis, the middle transmission shaft movable relative to the proximal transmission shaft from a first position where the first and second longitudinal axes are in a parallel orientation to a second position where the first and second longitudinal axes are in a non-parallel orientation;
• and
• a distal transmission shaft including a fourth gear disposed at a proximal end thereof and meshingly engaged with the third gear, the distal transmission shaft defining a third longitudinal axis, the distal transmission shaft movable relative to the proximal and middle transmission shafts,
• wherein the first, second, third and fourth gears define an elliptical shape along each respective axis of the first, second, and third longitudinal axes, the first, second, third, and fourth gears maintaining rotatable engagement during a respective movement of the proximal, middle, and distal transmission shafts.