A low cost disposable flexible reamer shaft has a flexible cylindrical braided tube shaft with an outer diameter in the range of 4 to 14 millimeters and 250 to 400 mm length, and a central aperture for insertion of a flexible polymeric tube. The braided tube shaft is permanently attached to a first end element and a second end element. The threaded end of the first end element attaches to female threads of modular tapered, cylindrical or spherical, hollow or solid reamer assembly. The second end element fits into a chuck of a drive motor. The threaded attachment of the first end provides local centerline matching. A guide pin is inserted in the bone cavity, which enters the reamer. The central aperture of the flexible polymeric tube provides centerline matched, wobble-free reaming. The reaming end point is precisely the guide pin inserted location while the reaming direction is controlled by the surgeon by flexing the flexible reamer shaft.