Moveable interface between a stepper and a stabilizer

A stabilizer and stepper assembly for performing a medical procedure, the assembly comprising:

• a stabilizer comprising a plurality of stabilizer joints supporting multi-directional motion;
• a stepper for holding an elongate medical instrument having a longitudinal axis, the stepper supporting linear, rotational or both linear and rotational motion of the medical instrument on its longitudinal axis;
• a compound rotational interface operably connected to the stabilizer and the stepper;
• the compound rotational interface comprising a compound pinned parallelogram in a scissor arm arrangement bound by a first end coupled to the stabilizer and a second end coupled to a first rotational joint of the compound rotational interface, the first rotational joint coupled to the stepper, rotation of the stepper relative to the compound pinned parallelogram provided on an axis of rotation defined by the first rotational joint;
• the compound pinned parallelogram moveable from a first linear position to a second linear position and the first rotational joint moveable from a first angular position to a second angular position;
• and
• a linear direction defined by the compound pinned parallelogram substantially perpendicular to the axis of rotation defined by the first rotational joint, and the axis of rotation substantially perpendicular to the longitudinal axis of the medical instrument.