A device for excising a cavity within bony tissue, the device having a proximal end and a distal end opposite the proximal end, and extending along a longitudinal device axis between the proximal and distal ends (110, 112), the device comprising: a handle assembly proximate the device proximal end and extending distally along the longitudinal device axis; an outer tube extending distally from the handle assembly, a distal end of the outer tube positioned proximate the device distal end; an actuation mechanism; and a blade assembly connected to the handle assembly and the actuation mechanism, and aligned with the longitudinal device axis, the blade assembly terminating proximal to the device distal end; the blade assembly comprising a blade body (334, 204) having a proximal end and (330, 201) a distal end (332, 202) and first and second opposing sides (348, 350, 218, 220) extending therebetween, the first side (348, 218) having a first curved cutting edge (356, 246); wherein the blade assembly comprises a first configuration in which the blade body (334, 204) is contained within the outer tube; and wherein the blade assembly comprises a second configuration in which at least a portion of the blade body (334, 204) is projected away from the longitudinal device axis and out of the outer tube, and in which the blade body (334, 204) is in contact with a first stop surface so that independent movement of the blade body (334, 204) relative to the device is limited; wherein the first stop surface is located on the outer tube; characterised in that the device further comprises a second stop surface located on the blade assembly, wherein in the second configuration the blade body (334, 204) is captured between and in contact with the first and second stop surfaces (296, 316). a handle assembly proximate the device proximal end and extending distally along the longitudinal device axis; an outer tube extending distally from the handle assembly, a distal end of the outer tube positioned proximate the device distal end; an actuation mechanism; and a blade assembly connected to the handle assembly and the actuation mechanism, and aligned with the longitudinal device axis, the blade assembly terminating proximal to the device distal end; the blade assembly comprising a blade body (334, 204) having a proximal end and (330, 201) a distal end (332, 202) and first and second opposing sides (348, 350, 218, 220) extending therebetween, the first side (348, 218) having a first curved cutting edge (356, 246); wherein the blade assembly comprises a first configuration in which the blade body (334, 204) is contained within the outer tube; and wherein the blade assembly comprises a second configuration in which at least a portion of the blade body (334, 204) is projected away from the longitudinal device axis and out of the outer tube, and in which the blade body (334, 204) is in contact with a first stop surface so that independent movement of the blade body (334, 204) relative to the device is limited; wherein the first stop surface is located on the outer tube; characterised in that the device further comprises a second stop surface located on the blade assembly, wherein in the second configuration the blade body (334, 204) is captured between and in contact with the first and second stop surfaces (296, 316).