An atherectomy system includes a multiple use assembly and a single use assembly that is adapted to releasably engage with the multiple use assembly. The multiple use assembly includes a drive motor having an output shaft, a first magnetic coupling segment that is rotatably coupled to the output shaft and a circuit that is adapted to control operation of the drive motor. The single use assembly, intended to be disposable, includes a second magnetic coupling segment that is adapted to rotatably engage the first magnetic coupling segment, a spline shaft that is rotatably coupled with the second magnetic coupling segment, a drive gear assembly that is translatable along the spline shaft, and a drive shaft that is operably coupled with the drive gear assembly and is adapted to rotatably engage an atherectomy burr.