An atherectomy device comprising: a catheter including a distal nosecone fixedly coupled to a flexible section by a bushing (1391, 1491) that defines a fixed bend of the catheter, wherein the catheter includes a cutter window distal to the fixed bend, wherein the flexible section includes a longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) on a side of the flexible section; and a cutter (1303, 1403) coupled to a rotatable driveshaft within the catheter, wherein proximal movement of the cutter (1303, 1403) and the rotatable driveshaft causes the cutter (1303, 1403) to slide along an edge (1315, 1415) of the bushing (1391, 1491) to cause the cutter (1303, 1403) to tilt in a first direction and to extend through the cutter window, wherein, when the cutter (1303, 1403) is extended through the cutter window, a force applied to the rotatable shaft in a proximal direction places compression on the flexible section that causes the flexible section to bend away from the longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) and to take on a curvature, and wherein distal movement of the cutter (1303, 1403) and the rotatable driveshaft causes the cutter (1303, 1403) to tilt in a second direction opposite the first direction and to retract within the cutter window. a catheter including a distal nosecone fixedly coupled to a flexible section by a bushing (1391, 1491) that defines a fixed bend of the catheter, wherein the catheter includes a cutter window distal to the fixed bend, wherein the flexible section includes a longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) on a side of the flexible section; and a cutter (1303, 1403) coupled to a rotatable driveshaft within the catheter, wherein proximal movement of the cutter (1303, 1403) and the rotatable driveshaft causes the cutter (1303, 1403) to slide along an edge (1315, 1415) of the bushing (1391, 1491) to cause the cutter (1303, 1403) to tilt in a first direction and to extend through the cutter window, wherein, when the cutter (1303, 1403) is extended through the cutter window, a force applied to the rotatable shaft in a proximal direction places compression on the flexible section that causes the flexible section to bend away from the longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) and to take on a curvature, and wherein distal movement of the cutter (1303, 1403) and the rotatable driveshaft causes the cutter (1303, 1403) to tilt in a second direction opposite the first direction and to retract within the cutter window. wherein proximal movement of the cutter (1303, 1403) and the rotatable driveshaft causes the cutter (1303, 1403) to slide along an edge (1315, 1415) of the bushing (1391, 1491) to cause the cutter (1303, 1403) to tilt in a first direction and to extend through the cutter window, wherein, when the cutter (1303, 1403) is extended through the cutter window, a force applied to the rotatable shaft in a proximal direction places compression on the flexible section that causes the flexible section to bend away from the longitudinal spine (560a, 560b, 660a, 660b, 960a, 960b, 1160a, or 1160b) and to take on a curvature, and wherein distal movement of the cutter (1303, 1403) and the rotatable driveshaft causes the cutter (1303, 1403) to tilt in a second direction opposite the first direction and to retract within the cutter window.